Hoverflies of Britain and North-west Europe : A Photographic Guide 9781399402453, 9781399402477, 9781399402484

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Hoverflies of Britain and North-west Europe

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Hoverflies of Britain and North-west Europe Sander Bot & Frank Van de Meutter

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BLOOMSBURY WILDLIFE Bloomsbury Publishing Plc 50 Bedford Square, London, WC1B 3DP, UK 29 Earlsfort Terrace, Dublin 2, Ireland BLOOMSBURY, BLOOMSBURY WILDLIFE and the Diana logo are trademarks of Bloomsbury Publishing Plc First published in 2019 in the Netherlands as Veldgids Zweefvliegen by KNNV First published in the United Kingdom 2023 This electronic edition published in 2023 by Bloomsbury Publishing Plc Copyright © 2019, KNNV Uitgeverij, Zeist Translation © Sander Bot & Frank Van de Meutter Photographs © Sander Bot with the exception of those featured on the cover Sander Bot and Frank Van de Meutter have asserted their right under the Copyright, Designs and Patents Act, 1988, to be identified as Authors of this work All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage or retrieval system, without prior permission in writing from the publishers Bloomsbury Publishing Plc does not have any control over, or responsibility for, any third-party websites referred to or in this book. All internet addresses given in this book were correct at the time of going to press. The authors and publisher regret any inconvenience caused if addresses have changed or sites have ceased to exist, but can accept no responsibility for any such changes A catalogue record for this book is available from the British Library Library of Congress Cataloguing-in-Publication data has been applied for ISBN: PB: 978-1-3994-0245-3; ePUB: 978-1-3994-0247-7; ePDF: 978-1-3994-0248-4

Typeset in Frutiger LT Light Condensed by Susan McIntyre Maps and diagrams by Stuart Ball

To find out more about our authors and books visit www.bloomsbury.com and sign up for our newsletters Cover photos © Frank Vassen Front cover top: Leucozona glaucia; bottom (left to right): Helophilus trivittatus, Sphaerophoria scripta, Xanthogramma pedissequum Spine: Microdon myrmicae Back cover (left to right): Caliprobola speciosa, Paragus haemorrhous, Criorhina floccosa

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Contents Quick index

6

Acknowledgements

7

Introduction

8

Is it a hoverfly?

8

Finding hoverflies

14

Hoverflies as a way to evaluate and appreciate the environment

16

Identifying hoverflies

16

Is collecting still necessary?

18

Creation of this guide

18

Keys

24

Main key

24

Key 1

24

Key 1A  Ant flies Microdon puparia

28

Key 2  Plumehorns Volucella

28

Key 3

30

Key 3A

40

Key 3B  Blacklets Cheilosia and Garlic eater Portevinia

44

Key 3C

54

Key 4

64

Key 4A  Globetails Sphaerophoria

76

Key 4B

80

Key 4C  Aphideaters Eupeodes

82

Key 5

86

Key 6

94

Species accounts

102

Index

399

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Quick index English common names ant flies 105 aphideaters 159 Aspen logsitter 293

globetails 167 grass skimmers 213 Great banded gossamer 145

Bear fly 147 bighorn flies 271 blacklets 225 bristlesides 131 brusheyes 137 bulb flies 367 bumbleflies 381

haireyes 357 halfbands 119 hoaries 147 hornet flies 377 Hornet giant 375

Clubrush fly 347 Common batman fly 343 Common compost fly 397 Common dainty 211 copperbacks 267

Jewel wood fly 375 lagoon flies 341 leafwalkers 387 Logjammer 387 longhorns 219 lucents 143

psyllid-killers 285 pufftails 319 Ringed beech fly 127 roundfaces 359 roundtails 117 sapeaters 293 sedgesitters 185 shimmers 313 smoothlegs 291 smoothtails 149 smoothwings 157 snout flies 269 Snouted duck fly 345 spikelegs 287 spinelegs 301 Spotted garlic eater 225 Stripe-backed glimmer 311 stripebacks 349 swamp flies 345

Eurasian pocota 385

Marmalade hoverfly 115 marsh flies 351 meadow flies 107 Migrant flatbelly 211 mimics 343 mucksuckers 313 Mugwort galleater 273

falsehorns 377 fen flies 323 flatfaces 273 flower flies 127 forest flies 385

Phantom potterfly 177 Pine hoverfly 375 pitheads 279 plumehorns 371 pond flies 353

Vermilion fly 267

Anasimyia 345

Ferdinandea 267

Baccha 211 Blera 375 Brachyopa 293 Brachypalpoides 389 Brachypalpus 385

Hammerschmidtia 293 Helophilus 351 Heringia 291

Pelecocera 271 Pipiza 279 Pipizella 273 Platycheirus 185 Pocota 385 Portevinia 225 Psarus 267 Psilota 357 Pyrophaena 209

dayglowers 177 Dimorphic bumblefly 381 drone flies 329 duskyfaces 181

thicklegs 397 thintails 115 wasp flies 223 whitebelts 145 wrinkleheads 303

Scientific names

Caliprobola 375 Callicera 219 Ceriana 223 Chalcosyrphus 387 Cheilosia 225 Chrysogaster 309 Chrysotoxum 107 Criorhina 381 Dasysyrphus 137 Didea 143 Doros 177 Epistrophe 149 Epistrophella 155 Episyrphus 115 Eriozona 147 Eristalinus 341 Eristalis 329 Eumerus 359 Eupeodes 159 Eurimyia 345 Fagisyrphus 127

Lapposyrphus 159 Lejogaster 313 Lejops 347 Leucozona 145 Mallota 343 Matsumyia 381 Megasyrphus 145 Melangyna 119 Melanogaster 303 Melanostoma 181 Meligramma 117 Meliscaeva 115 Merodon 367 Microdon 105 Milesia 375 Myathropa 343 Myolepta 301

Rhingia 269 Riponnensia 311 Scaeva 157 Sericomyia 353 Sphaerophoria 167 Sphegina 319 Sphiximorpha 223 Spilomyia 377 Syritta 397 Syrphus 127

Neoascia 323 Neocnemodon 287

Temnostoma 377 Trichopsomyia 285 Triglyphus 273 Tropidia 397

Orthonevra 313

Volucella 371

Paragus 213 Parasyrphus 131 Parhelophilus 349

Xanthandrus 211 Xanthogramma 177 Xylota 391

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Acknowledgements The basis of this book is the Dutch field guide Veldgids Zweefvliegen, published by KNNV publishing in the Netherlands in 2019. The current book, however, is not just a simple translation. The text has been completely revised, and the book has been expanded to include full species accounts of an additional 12 species. Furthermore, the text has been rewritten to include identifications of British species, and descriptions of the ecology of the British fauna, and distribution maps and flight-time diagrams for a much larger area, including the British Isles, have been added. We would not have been able to write this book without funding from the Meester Prikkebeen Fund, part of the Prins Bernhard Cultuurfonds, and the Uyttenboogaart-Eliasen Foundation. A special thanks goes to Christophe Brochard. First, he taught us how to make a camera set-up and how to take good photographs with it. Over the years, Christophe continually worked with us at improving the set-up. In addition, the images with the finest detail were taken by him using his personal microscope set-up; they could not have been produced with a standard camera. Without his immense help, we would not have images of such high quality. To be able to take all the 1,797 photos for this book, we needed not only a specialised camera set-up, but also the flies themselves. Obtaining them was quite a challenge. The material needed to be preserved well (i.e. appropriately pinned), and we wanted to include so-called mythical, very rarely observed species, while using specimens preferably from within the geographical scope of this book. Our own collections were not sufficient for this, so help from colleagues and museums was essential. Consequently, in recent years, there has been a lively traffic of rare hoverflies from collections to our office, with people and museums entrusting us with these precious fly specimens for a long time. We sincerely thank them for their trust. These are, in order of number of flies supplied: Naturalis Biodiversity Center Leiden (collection manager Pasquale Ciliberti), Jeroen van Steenis, Gerard Pennards, Elias de Bree, Jonas Mortelmans, John Smit, Chris Palmer, Wouter van Steenis, Leendert-Jan van der Ent, Steven Vantieghem, Wout Opdekamp, André van Eck, Bastiaan Wakkie, Tim Faasen, Jan Versigghel, Menno Reemer, The Natural History Museum London (Nigel Wyatt), The Royal Belgian Institute of Natural Sciences (Wouter Dekoninck and Pol Limbourg), Menno van Zuijen, Franz Malec, Lenze Hofstee, Zoological Research Museum Alexander Koenig Bonn (Ximo Mengual), Biological Museum Lund (Rune Bygebjerg), Steven Falk, Peter Lindenburg, Rune Bygebjerg, Aat Barendregt (now deceased), Jan Edelsjö, Niklas Johansson, Xavier Lair, �ukasz Mielczarek, Naturhistorisches Museum Bern (Hannes Baur), Lisa Fisler and Wil van der Hoven. A novel feature of this book also is that it provides common names for all species. This was a difficult task, as some names were already in circulation and many British species have been given a name by Steven Falk on his excellent Flickr website (www.flickr.com/photos/63075200@N07/collections/72157629600153789/...). However, common names are also given in the Field Guide to the Flower Flies of Northeastern North America by Jeff Skevington and Michelle Locke. Because several species are found in both America and Europe and, in fact, most of the genera are shared, there was a risk that two parallel naming systems for hoverflies would evolve. To avoid this, we worked with Steven Falk (artist, naturalist and photographer) and Jeff Skevington to devise a system that we hope will unify the thus-far diverging naming systems. Steven and Jeff, thanks a lot for the discussions and ideas that led to the common names we have used. Before sending the manuscript to the publisher, we asked Steven Falk to review the manuscript. Thanks a lot Steven for the considerable corrections and for sharing your immense knowledge of British hoverflies. Ximo Mengual and Jeff Skevington, thanks for the taxonomic advice. Many people and institutions shared data on the hoverflies of their region (see the section on creating the maps): without their help and cooperation, we would not have been able to include the maps and phenology bars. This brings us to Stuart Ball. He has been truly amazing in producing the maps and the phenology bars. He’s a wizard with data handling and programming, but what’s been most exceptional has been his willingness to instantly address the dozens of comments or requests for changes we fired at him. Stuart, we hope you know how much we appreciated this. And finally, Sander would like to thank Janne Ouwehand, the love of his life: Janne, you’re incredible! Frank tries to fathom how it is to live together with a husband or a father that is distracted with every buzzing of a fly, and strays into the bushes at many an inconvenient time. The closest he gets to understanding is that it must be very, very hard sometimes, and that utter patience is required! Thanks Olga, Annebel and Mauro, my beloved ones! 

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Introduction Is it a hoverfly? In the field, most hoverflies will be readily identifiable as hoverflies owing to their typical behaviour and their bright colours. Some, however, are very dull and look like regular flies, while others are champions of mimicry and not only are near-perfect wasp or (bumble)bee imitations, but also behave like them. The following hints should help you to recognise every hoverfly you encounter. A hoverfly that resembles a bee or wasp can be recognised by looking at its wings. Hoverflies belong to the insect order Diptera (flies), the name being derived from the Greek two and wing, meaning they have one pair of wings. Bees and wasps belong to the Hymenoptera and have two pairs of wings. The second pair of (hind)wings that would have been present in the ancestors of flies has not totally disappeared: it is now reduced to the halteres that today’s flies use for balance while flying. Furthermore, hoverflies have only three antennal segments (bees and wasps have many), which means that the antennae are usually much shorter, but not always. In species that rely on wasp mimicry, the appearance of a longer, wasp-like antenna is thanks to different modifications: some species have a spine on the head, on top of which the antennae stand; some have elongated antennal segments; while in others the colour and shape of the fore legs mimics those of wasp antennae and the flies wave them along the head as wasps do with their antennae! Within Diptera, the hoverflies can be recognised by their wing venation (and this feature is also used to identify the different tribes and genera of hoverflies). Hoverflies are the only flies with a false vein (Photo 1). As for every rule, there are some exceptions: the false vein is missing in Eristalinus sepulchralis and in Psilota it is hard to discern. Other typical (but not unique) features of hoverflies are the closed wing cells r4+5 and cua (Photo 1), ‘closed’ meaning that the cell is completely surrounded by veins. The wing cell cua is long and pointed, and ends near the wing margin. Regarding the antenna, in some similar-looking fly families the arista is terminal, but in hoverflies it is usually on the dorsal side of the third antennal segment. Among the few exceptions to this are mainly species that mimic wasps; in these species, the arista is terminal and makes the antenna look longer (Ceriana, Sphiximorpha, Callicera) to improve their likeness to wasps. Hoverflies also lack the black, bristle-like hairs on the thorax and legs that are found in house flies or tachinid flies (the exception: Ferdinandea). Once a fly is recognised as a hoverfly, the next step is to identify it to species. For this, a good knowledge of hoverfly anatomy is essential, and the following photographs show all the body parts relevant for identification. All hoverflies share the same basic body plan. However, the arrangement of their body parts, and especially the relative proportions, may vary considerably. We believe it is best to memorise the basic components, and then try to find them in the different species. It can be important to know whether your fly is a male or a female. The easiest feature to use for finding that out are the eyes. In females, the eyes are separated; if the eyes meet each other, the fly is always a male. However, there are quite a few species in which the eyes of the male are also separated (e.g. Anasimyia, Helophilus, Pelecocera) but usually less so than in the females. Therefore, also check the underside of the tip of the abdomen. The male has a small to very large complex asymmetrical structure that is curled ventrally, or under (the genitalia), creating a bulging tip to the abdomen; while the abdomen in the female ends symmetrically in an – often retracted and barely visible – ovipositor, with no bulge at the end. Occasionally, intersex specimens occur, in which the eyes are separated but the gap is less than in typical females. Such flies share features of both males and females, or may be darkly coloured, and they cannot be identified with the keys (or they will not be correctly identified). Be aware of this possibility when confronted with a strange-looking female fly. Compare the distance between the eyes with that of other females of the same species, and check for slightly wrinkled abdomens and swollen or deformed legs and tarsi, which often indicates an intersex individual.

false vein

cell r4+5 cell cua Photo 1 The wing of a hoverfly. 8 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROPE

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Spineleg Myolepta

Plumehorn Volucella

Aphideater Eupeodes

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Sapeater Brachyopa

wing Sapeater Brachyopa

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Aphideater Eupedes

abdomen ventral view Aphideater Eupedes

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Grass skimmer Paragus

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Globetail Sphaerophoria

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Finding hoverflies In the spring and summer, you can see hoverflies everywhere. Yet many species are hard to find unless you know how to search for them. Inexperienced observers often see few species and encounter the same species over and over again. Detecting hoverflies in your environment efficiently requires knowledge and experience. The best way and places to find hoverflies vary from district to district, from day to day and even during the day. Here are some tips and tricks that can help you find many species of hoverflies.

Flowery places

Okay, we realise this may sound rather obvious: hoverflies visit flowers for foraging. But there is more to this. Not all flowers are equally favoured, and flower preferences differ between species. If your aim is to find as many species as possible in a single place, it is best to combine two strategies: finding a patch of flowers that attracts many and a large variety of hoverflies and finding specific flower types known to be visited by specialised species. Flowers that attract many hoverflies usually produce much and easily accessible nectar because most hoverflies require nectar for feeding and have a short tongue. Very attractive hover-fly flowers include umbellifers (e.g. Cow parsley, hogweeds, angelicas, parsnips), willows, maple trees (including Sycamore), hawthorns, Prunus trees (including Blackthorn and cherries), brambles and Ivy. Some species specialise in flowers with nectar that is more difficult to reach. For example, Rhingia prefers the flowers of the mint family, with their deep, narrow calyx. Some hoverflies have a pronounced preference for a particular flower colour. Sericomyia bombiformis and S. superbiens like large blue and purple flowers (Devil’s-bit scabious, Field scabious, thistles) while Cheilosia canicularis prefers large, yellow flowers of the aster family and is especially fond of Canadian hawkweed. Also, the height and size of the flowers is important. Have a close look at small and low flowers (stitchworts, eyebrights, Common tormentil, bedstraws) for Sphaerophoria, Paragus, Eumerus and Neoascia. Conversely, there are also species that live high in the canopy of forests and visit flowers in trees and at the top of shrubs (e.g. Mallota, Criorhina, Pocota). Binoculars can come in handy here! And, maybe unexpectedly, on flowering grasses, sedges, rushes and plantains you can find a wealth of sedgesitters. Finally, some species are rarely seen on flowers at all. Xylota walk over leaves of trees in the forest edge, looking for windblown pollen and the sugary excretions of aphids. Their food disappears during heavy rain and they may turn up at flowers for a short time afterwards. Finally, Microdon species do not appear to visit flowers at all! The same flower may prove less or more attractive to hoverflies, depending on where the plant grows. Most of our hoverflies are linked to forest or tree habitats so are mainly found on flowers near forest. All hoverflies hate breezes, and this certainly applies to the specialised forest hoverflies (e.g. Brachyopa). A small, sheltered woodland ride or a forest glade with the right flowers can be extremely rewarding. Some forest hoverflies take it a step further and rarely come out in full sun: the delicate Baccha elongata and Sphegina are often found in dappled sunlight or full shade, the latter nearly always near small streams in forest.

Foodplants: know your ecology!

Our knowledge of the ecology of hoverflies is rapidly increasing, which is extremely helpful when trying to find them. Knowing more about larval ecology, and especially the host plants of herbivorous species, helps us to predict which species can be seen where based on the composition of the vegetation. As soil type, current and historical land use, landscape composition and management, and climatic variables together shape the local vegetation, these variables also may indicate which (especially herbivorous) hoverfly species can be expected where. Some examples. Cheilosia, Eumerus, Merodon and Portevinia are all herbivorous hoverflies and often depend on one or a few plant species for their development. Portevinia maculata and Cheilosia fasciata can be found only in the vicinity of Wild garlic. Cheilosia pubera lives in Water avens. The distribution of these plants in Great Britain is well known and can be discovered with a few clicks: then, you can know exactly where to look for these hoverflies. This knowledge can even help you to fill in apparent gaps in the distribution of a hoverfly in areas where there are few records. Be aware, though, that some species are quite mobile, and where they complete their larval stage may be kilometres from where they forage as adults. For example, the larva of Cheilosia canicularis lives in Butterbur in river valleys, but the adults are mostly found at some distance on the drier higher banks, e.g. on Canadian hawkweed. Again, knowing this, you can optimise your catch. And although the foodplants of many Cheilosia species remain unknown, it just takes a bit of luck to get a break. If you see a female ovipositing on a plant – maybe a pre-flowering leaf rosette – try to make a note of species of fly and plant. This information could be significant and add to our understanding of that species. You will soon learn that female Cheilosia species spend some of their time sitting on their foodplants; e.g. Cheilosia albipila often rests on rosettes of Marsh thistle. It is not just adult herbivorous hoverflies that have a special attachment to certain plant species. The larvae of many species prey on aphids, psyllids or caterpillars that themselves live only on one or a restricted set of plant species. As a case in point, the larva of Platycheirus perpallidus is fond of the aphid Trichocallis cyperi, which is almost only ever found in large stands of Bottle sedge. Moreover, P. perpallidus appears to be restricted to the places where Bottle sedge grows in permanently inundated conditions. In the genus Dasysyrphus, there are species whose larva eats aphids only on deciduous trees, and others eat aphids only on coniferous trees. This specialisation, of consuming aphids of either deciduous or coniferous trees, can also be found in various other groups of hoverflies (e.g. Parasyrphus, Melangyna, Didea), resulting in completely different species communities in, for example, a spruce forest compared to an oak forest. We have tried to include as much of this critical information as possible in the species texts, to help you find and/or identify these species. 1 4 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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Weather

Hoverflies in our temperate region like sunny weather and mild temperatures. On a sunny day, they are most active at a temperature of about 16–22°C (in the shade). When it is colder, they will often sun themselves to warm up. After a cold spring night, you can find large numbers of hoverflies in the morning on the east-facing forest edges and hill slopes, sitting on the leaves or the grass. The bonus for us is that all hoverflies participate in this: you could find a Criorhina, a Brachyopa, a Mallota, a Syrphus and a Melangyna next to each other in the morning, but later in the day they all will have returned to their specific habitats and some may become near-impossible to find. On rather cold but sunny days, you can also see this behaviour in the evening on the western edge of forests. When it is overcast, there are often still a few species active; some are even more active than at full sun, such as Platycheirus and Melanostoma. In heatwaves, hoverflies are more likely to visit flowers in the shade (especially in the forest interior) or to restrict foraging to early morning before the heat builds up. At midday, most species seem to have disappeared. They have gone to a cool resting place (often the underside of leaves) to avoid desiccation and overheating. Moreover, flower nectar production and availability is much reduced during the heat of the day so foraging is less efficient. Some of the flies will start searching for water, especially during prolonged dry periods and with strong dry winds. Damp forest paths, edges of streams, and other similar watery habitats can attract large numbers of flies at such times. As when hoverflies are sunning, the species palette that descends for drinking is different from that on flowers. Species of the genera Parasyrphus and Neocnemodon are remarkably more common at drinking sites, and also the enigmatic Callicera species are often seen this way. Presumably they are largely arboreal species that come down to drink during droughts. If you can’t find a natural drinking spot, you can easily make one by lightly spraying the lawn with a garden hose. This works best in a semi-shaded spot. In a garden in Belgium, over 80 species – including all five species of Neocnemodon – were observed this way, while the Neocnemodon species were otherwise rarely or never seen there. When the sun breaks through the clouds after a few days of bad weather, the numbers of hoverflies on flowers may be unusually high. Their energy reserves are low, and they need to refuel. In contrast, when suitable weather continues for a longer period, the number of hoverflies on flowers may decrease after a few days. The flies’ energy reserves are optimal and the animals are focusing now on reproduction. A last but very important point is that hoverflies generally hate breezes. On your search for hoverflies, try to seek out flowers that are sheltered from the wind. And if the day is cool and breezy, by concentrating on sheltered flowers your search can be very productive. The combination of all the above factors means that the number and diversity of hoverflies can change greatly from day to day, and that the best spot to look for them may change constantly.

What is the best season?

Adult hoverflies can be seen almost all year round, but the best season is spring. The vast majority of hoverflies overwinter as pupa or as larva. Only a few species overwinter as adults (e.g. Eristalis tenax, Eristalinus aeneus and Episyrphus balteatus). They start to fly as soon as the weather permits, and are therefore also seen on warm sunny days during the winter months. Species that overwinter as pupae or larvae may fly from March to October (nowadays often February–November), depending on species. Hoverflies can be divided into two large groups based on the number and timing of their cohorts throughout the year. The first group flies in both spring and summer. They have several generations in a year: usually two, but some species produce successive cohorts as long as the weather permits (e.g. in some Paragus species there are up to four generations in a year). Usually the cohorts vary in size: some species have a large spring generation and only a small generation later in the summer, but in other species the summer population is much larger (especially in species that migrate). The second group consists of the species with only one generation per year. Almost all of them fly exclusively in spring, which is why spring is the best period of the year to find many species of hoverflies. Species tallies for each day of the year have a bimodal distribution, with the highest peak mid-May to mid-June (depending on height and latitude), and a second but much lower peak at the beginning of August.

Specific behaviours

Many hoverflies gather at high points in the landscape, in a behaviour called ‘hill-topping’. Any small hill will do, as long as it rises above its surroundings. Hills with some bushes or small trees near the top yield more species than treeless hill-tops. Each species has its own behaviour at hill-tops, and this may vary during the season or between hill-tops. Many hoverflies form loose swarms at wind-sheltered spots near the top (Epistrophe, Epistrophella, Melangyna, Platycheirus, Rhingia, Xanthogramma), while others sit on bark (Chalcosyrphus, Ferdinandea), near tree bases (Criorhina), on leaves of bushes and trees (Chrysotoxum, Pipizella, Pipiza) or on the ground (Eupeodes, Eristalis). The more isolated and the pointier a hill-top, the more concentrated and abundant are hoverflies there. Because several very rare species perform hill-topping they are (far more) easily found this way than using other searching techniques. For example, Callicera rufa will often sit on or hover next to large trees on hill-tops. A very interesting group of hoverflies with a specific behaviour are the sap-run species. Species of Brachyopa, Hammerschmidtia and Ferdinandea, and Volucella inflata, are some of the hoverflies you can find at sap runs on trees. Sap runs can be looked for but can also be found by their typical scent. Not every sap run will yield the same species: different trees may attract different species of hoverflies, but also size and exposure of the sap run play a role. A large sap run with abundant sap will more likely attract Brachyopa insensilis, Sphiximorpha subsessilis or Volucella inflata than will a small, hardly visible subcortical sap run, where more often Brachyopa bicolor, B. scutellaris or B. pilosa are seen. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 1 5

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Hoverflies as a way to evaluate and appreciate the environment One of the most fulfilling outcomes of accumulating knowledge on hoverflies is that, at some point, you will be able to read the history of a place and to evaluate its current ecological state only by looking at its hoverflies. Finding yourself in a place that has all the species that it possibly can have is not only very exciting. That knowledge also tells you that the place has a long, stable and benign history, that current threats have not (yet) had their worst effects, that biodiversity is still at its zenith. Such things often cannot be read from how habitats look today. All too often, many species of hoverflies are lacking even from our best-looking natural areas, whereas outwardly degraded systems may be hotspots of hoverfly diversity. A great instrument to detect this hidden quality of natural areas is Syrph the Net: the database of European Syrphidae (Diptera) by Martin Speight and collaborators. It provides reference data to calculate the quality and intactness of a natural area based on the presence of hoverflies.

Identifying hoverflies Photography

With this field guide in your pocket, you can go outside to identify hoverflies. Many observers in the field will only use a camera and will not want to collect specimens. You will soon learn that many hoverflies can be identified by photos alone, especially if you use a good macro lens and photograph the fly from different angles so you can see all necessary features. The great thing about photos is that they can be posted on online forums such as the UK Hoverflies Facebook Group, iNaturalist (https://www. inaturalist.org) and Observation.org (https://observation.org), where experts can often accurately identify even poor photographs, based on the overall impression or appearance of a species (the ‘jizz’). Such experts can also quickly tell you if your identification is wrong. Many photographs, however, do not show the fly in such a way that permits identification, so a substantial number of hoverflies can never be identified from photographs.

Catching

With increasing concerns about the fate of hoverflies and our pollinators in general, paradoxically, it has become even more important to regularly catch and even collect hoverflies. Each observation of a hoverfly is valuable, yet – as mentioned above – using photography alone means that a large share of the hoverfly fauna cannot be identified, and information about it will not be stored in databases and will be disregarded in analyses. For catching and identifying in the field, an insect net and a hand lens are needed. Opinions differ, but a net with a mouth diameter of c. 16 inch (40 cm) is the most popular. In spring, a longer pole (and preferably an extendible one) on the net can be useful to catch flies in flowering bushes and trees, but in meadows a shorter stick is usually handier. As to the colour of the net, some prefer darker colours (green, black) as it is believed that they allow for a stealthier approach to the fly, yet a white net may make it easier to find the fly once it is in the net. With a hand lens, you can much better study the fly in the field than with the naked eye. Lenses often have a magnification of 10x to 20x. 10x may be too small a magnification to, for example, determine the colour of the hairs on the top of femur 3 in Syrphus, so 15x or 20x magnification might be preferred. Unfortunately, you will discover that a certain proportion of species still cannot be identified in the field (this number will decrease with experience). There are two options now. Either you let the fly go and accept that you cannot identify everything, or you take the fly home to study it further under the microscope.

Collecting and curating

If a specimen is required for further study, a tube is needed. You can take small tubes and transport flies individually or take a slightly larger plastic bottle with a narrow entrance and stopper, and keep all the catches for a specific area in it. If you visit several areas in one day, make sure you use different bottles and remember which flies come from which area, or take several labelled bottles. Once captured, the fly must eventually be killed. This can be done by putting the jar in the freezer for a few hours, or by adding a small wadge of tissue/toilet paper soaked with a little ethyl acetate to the jar. The ethyl acetate sedates the flies within a minute but can take an hour or so to actually kill them, depending on how much you use (use too little and they may eventually wake up again!). Nail polish remover, which is more readily available, can be used instead of ethyl acetate. Be aware, use the acetone-free variant. A more natural but at least as effective method is putting bruised young shoots of Cherry laurel into the jar. After killing, the animal must be pinned. One approach is to pin the fly with a long pin. The pin is inserted through the thorax of the fly, approximately two-thirds of its length back from the head, leaving room on the pin above the fly for your fingers to handle it, and room below to add labels and insert the pin into the collection box or tray. There are various sizes of insect pins on the market, but size 0 or 1 will do for most species. The other approach is to pin the fly with a shorter micro-pin onto a Plastazote stage that has a longer pin going through it. By pinning the fly immediately after killing it, it is still flexible so that it can be set up neatly. The scientific value of the fly and your collection overall increases if you make sure that the characters important for identification are clearly visible. This can be done by pinning the fly temporarily on a thick piece of foam, so that its body (nearly) touches the foam. Then the legs can be folded open and rested on the foam. Next, the wings can be nudged opened with a pin and the head can be turned to face right if necessary. If the fly is a male, it is best to unfold the genitalia, especially in species where this helps 1 6 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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with, or is even necessary for, identification. Here, again use an insect pin, and pull the genitals out a little before you pin the fly close to the foam (Photo 2). Sphaerophoria are the easiest to prepare the genitals of: turn the genitals upwards so that they protrude above the abdomen. Usually they will stay in that position, displaying the important features. For other species, the genitalia usually cannot remain unfolded after pinning. Once the fly is just above the foam, fix the abdomen with pins, pull the genitals out again and fix the genitalia with pins (Photo 2). With micro-pins and a trained eye, you can now also stretch the genitalia themselves in such a way that all the diagnostic parts will be visible. Quite a hassle, but after some practice this becomes routine work. Store your pinned fly in a closed box away from walls or the floor to inhibit pests from entering the box. After a few days, the fly will have hardened and can be added to the collection. But not before putting a label under it (Photo 3). Unlabelled flies are almost worthless because you don’t know where and when they were collected. Labels are easy to make yourself, but prepare them to last for long. For example, use a 5pt font size and print, using high-quality ink, on 120g paper, so that you get small, sturdy labels. Always print collection location and date, and the name of the collector, on the label. Try to be specific enough with the location that other users of your collection know exactly where you mean. Stating GPS coordinates helps enormously. The identification can be put on a second label, preferably with the scientific name, year of the identification and the name of the person who made the identification. Using a second label for the identification means that, should the identification change in the future, the location label can be untouched and only the label with the name has to be changed. The identification should be placed under the first label. It is useful to pin this label upside down, so that it is easy to read when you turn the fly upside down. It is at this point that the fly can finally be moved to your collection. As with your temporary drying boxes, store your collection boxes somewhere dark and dry, away from walls and the floor to avoid mould and pests. Various carpet beetles and booklice will love your collection, and some collectors swear they have a preference for rare species, so buy storage boxes that close properly. In the long run, no collection will be spared. Check regularly for frass lying on the labels or underneath the flies. If you are too late, whole flies may be eaten. One solution is to place the storage box in the freezer for a day or two. A common preventive or curative measure is placing mothballs in the collection box. This is very effective, but has two major disadvantages: mothballs have an unpleasant smell and may be toxic to humans. After pinning the fly, it can be studied under the stereomicroscope. An inexpensive stereomicroscope usually has a magnification range of 10x to 40x. This range is good to observe virtually all of the features described in this book. Everything you need to catch hoverflies and/or to start a collection is available at Veldshop (www.veldshop.nl/en/), including expert advice from the first author of this book. In the UK, advice is available from the Dipterists Forum (https://dipterists.org.uk) and Hoverfly recording Scheme (http://hoverfly.uk/hrs/; which runs regular workshops).

Photo 2 Example of a freshly pinned Eristalis tenax.

Photo 3 Example of a pinned Chrysotoxum cautum. There is a second label with the specimen identification information below the location label.

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Is collecting still necessary? Killing and collecting hoverflies is often criticised as being unethical, outdated and unnecessary in this digital era. Collecting hoverflies also is considered to be a threat to the persistence of populations. Indeed, catching butterflies and dragonflies has become unusual and frowned upon, and some people view collecting hoverflies, bees, moths and the like the same way. These arguments may seem to make sense, but we want to stress that collecting hoverflies in general does not harm populations (see below), is still useful and can actually be essential in conserving scarcer species. Nowadays almost every bird, butterfly or dragonfly that is observed in Western Europe can be identified without the need to kill it. A few decent photos suffice to identify it and corroborate the observation. But the situation is different with hoverflies because: 1) many species can be confirmed only by examining their microscopic features, and 2) we continue to find new species and to redefine how we identify the known ones. Species to be identified under the microscope can be studied only by first killing the fly. This applies to all species for which the genitalia need to be examined, but also to species where only a set of subtle characters can resolve the identification, as for instance in many Cheilosia. Should collecting stop, we would get no more information about the occurrence of, for example, Pipizella, Cheilosia or Sphaerophoria species. An estimated 35% of the species in this book cannot be identified with certainty from regular photos. In reality, this number is often higher because photographs rarely show all the critical characters. In fact, the effect of only ‘photographic sampling’ in hoverflies is already apparent: recent trend analyses revealed that the numbers of small, dark and difficult to identify species have generally decreased and those of large and easily recognised species is increasing. This illustrates the need for continued collecting of hoverflies. National recording schemes are the backbone of scientific research on status, trends, range shifts and other key population information in hoverflies, but the value of such schemes depends wholly on accurate and unbiased recording. But even for species that are easy to identify, collecting specimens can still be useful. A collection is a potential archive of genetic variation and thus an important source for scientific research on the ecology, taxonomy, phylogeny or population health of a species. As to the taxonomy of hoverflies, even today, lookalikes of common and easily identifiable species continue to be discovered. A good example is Epistrophe olgae, a twin species of E. nitidicollis, that was described from the Russian Far East. After people realised it occurred in Europe as well, it was found to be widespread in Europe. Thanks to all the ‘Epistrophe nitidicollis’ collected so far, we are able to reconstruct its history and prevalence here. Another example is Myathropa florea, an unmistakable species that therefore does not need to be collected. However, recent genetic research has shown that it is actually a multi-species complex, two of which are probably present in Great Britain. For researchers, it is essential that this M. florea is collected so that large numbers of it can be studied and a first picture of its distribution and ecology can be drawn. Furthermore, for the individual, to become really good at identifying hoverflies, having a reference collection is indispensable. It is recommended that you have several specimens of each species, preferably from several regions or different times of the year. Indeed, many species may appear different in spring than in autumn. Often spring (or late autumn) generation individuals are furrier (e.g. Eristalis pertinax) and/or darker (Episyrphus balteatus, Eupeodes corollae), compared to individuals of the summer generation. By archiving this variation in your collection, you learn which characters are variable and to what extent, or you may discover new characters of a species. Eventually, this will help you improve your identification skills and produce more reliable data. The scientific value of collecting is clear, we believe, but does collecting flies come at a cost to the population of the species? There are no studies that have answered this question, but several facts suggest this is not the case. Hoverflies generally are hard to find compared to many other insects (e.g. butterflies, dragonflies). Many species are arboreal or hide within vegetation. They are also quite mobile and will be spread over a large area. These attributes make it difficult to collect a significant part of a population. That said, where rare species are clearly confined to a small area and can be collected efficiently, it is better not to collect more than one to three individuals, and preferably to collect just males, since this affects the population less than collecting females. Furthermore, do not collect in places where collecting is not allowed, such as protected nature areas. If you want to collect there, you must contact the owner in advance and seek permission. And, above all, always collect with respect for the environment.

Creation of this guide Photography

For this field guide, we decided to use photos of pinned hoverflies rather than photos taken in the field. Using the latter is destined to failure if your goal is to show the diagnostic features of all species. About 70% of the photos are from flies in the authors’ collections. For the remaining, 28 other collections provided specimens, for which we are most grateful. As much as possible we have used flies originating from the geographical scope of this book (mainly Belgium and the Netherlands), but for some 100 species, specimens from outside the area were obtained. Details on the origin of each of the specimens used herein can be obtained from the authors. The next challenge was to get everything photographed. To show the details of small hoverflies, a good camera set-up is a must. Building a good set-up is a time-consuming job that requires a lot of photographic knowledge. Fortunately, macro photographer Christophe Brochard was willing to share his expertise with us and helped extensively with assembling, and learning to work with, the camera set-up. The set-up consisted of a Canon 6D body, an MPE-65 macro lens, two flash units 1 8 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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and a macro rail along which the fly can be moved. For the tiniest details, such as of the genitalia, the set-up turned out to be inadequate and instead we used a microscope that had been converted into a camera by Christophe. Getting a fly completely in focus from top to bottom is not possible with a single photo because the depth of field is not sufficient. We used focus stacking to solve this. Here, the fly is moved gradually a fraction of a millimetre along the macro rail for successive photos, so the whole depth of the fly is covered. Image-merging software (Helicon Focus) was used to create a single completely sharp picture of the fly. More than 200 photos were taken to produce a single sharp image of the largest flies. All up, the number of clicks of the camera body for this project amounted to more than 150,000. Once the sharp photo was composed, it was further processed using Photoshop to: remove dust, loose hair and pollen grains from the animals, straighten their legs and wings, remove the pin, remove any reflective flash light or restore fresh colours (for discoloured specimens) (Photo 4).

Photo 4 In order to get a good picture of Spilomyia manicata for this guide, three different specimens have been photographed. Each photo consists of dozens of photos that together result in one sharp image. Extensive processing of the three photos in Photoshop yielded the final image at the bottom right. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 1 9

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Distribution maps and phenology bars

The maps cover more or less the geographical scope of this book, that is most of north-western Europe, including Belgium, Denmark, Luxembourg, Ireland, the Netherlands, Great Britain, and parts of western Germany and northern France. Observations made by both professionals and volunteers have been collated in recording schemes in some countries. Such data, for this purpose restricted to data gathered since 1990, were available from Belgium (128,815 records), Great Britain (1,115,878 records) and the Netherlands (429,518 records). Figure 1 shows the combined coverage of these three recording schemes in terms of occurrences in 10km by 10km squares (hectads). The numbers of records per square gives an indication of the distribution of recording effort. This clearly tends to follow the pattern of human population density, with recording concentrated in densely populated areas such as the south-east of England and the Netherlands and sparse in thinly populated areas such as the Highlands and islands of western Scotland. This variation in recording effort had a profound impact on our ability to map the distribution of hoverfly species. On average, the more records, the greater the chance of detecting a species. Thus, species that tend to occur in poorly recorded areas are less likely to be detected and their range is likely to be underestimated. Consequently, when assessing the distribution of a species, it is necessary to take the distribution of recording effort into account. This is an active area of research and increasingly sophisticated statistical methods are being developed. The method used here was FRESCALO. FRESCALO works by calculating the weighted, relative frequency of species in ‘neighbourhoods’ – a cluster of nearby localities (hectads in this case) – and then rescaling these frequencies according to the amount of recording in that neighbourhood. For each hectad, the list of species occurring in its neighbourhood is drawn up and the weighted relative frequency of each species is calculated as the sum of the number of occurrences falling in each hectad multiplied by the weight assigned to that hectad. Figure 2 shows how this sequence of steps results in a map for an example species, Tropidia scita. The middle pane illustrates the rescaled frequencies calculated by the FRESCALO analysis – the greater the rescaled frequency, the darker the green. Finally, these results are contoured to produce only three shades of green, for the final map. They show areas in which the species is abundant (dark green) through to scarce (lightest green). In the areas where detailed recording scheme data were not available, only whole-country presence (Denmark and Luxembourg) or whole-region presence (France, Germany and Ireland) were mapped. Data were sourced from publications and consultation with local specialists to attempt to assemble up-to-date species lists for these areas. Not all areas have up-todate species lists available and it was not possible to get hold of some recent data within a short time span. Therefore, some variation in how up-to-date the data were was inevitable. This may affect the distribution for species that have undergone drastic recent changes in range (e.g. Melangyna pavlovskyi, Cheilosia luteicornis, Leucozona glaucia). The coloured areas in Figure 3 show the countries and regions for which species lists were assembled. The grey areas in Figure 3 are outside the scope of this book.

Figure 1: Coverage – the hectads from which at least one record was received, 1990–2021 (left) and the numbers of records received from each square (right), where the area of the symbol is proportional to the number of records (capped at a value of 2,000; actual maximum was 16,071). 2 0 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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Figure 2: Distribution of Tropidia scita. The left-hand pane shows the hectads into which the available observations (1990–2021) fall. The middle pane shows the rescaled frequencies resulting from a FRESCALO analysis and, in the right-hand pane, these are contoured to produce areas in one of three shades as used in the maps included in the text.

Northern Ireland Denmark North & West

Schleswig-Holstein

Midlands & East

Niedersaschen Nordrhein-Westfalen

South Nord Pas de Calais Somme Figure 3: Countries and regions for which species presences were mapped.

Rheinland-Pfalz

Meurthe-et-Moselle Meuse Moselle

Hessen

Luxembourg

For the areas where detailed data were available, data could be used to present the phenology of a species. To represent regional variation, phenology strips for three different regions are shown: Belgium and the Netherlands, southern Great Britain and northern Great Britain. The phenology bars represent the weekly proportion of observations relative to all observations over the whole year. Deeper colours indicate weeks with a higher proportion of observations or, in other words, the peak of a species’ flight season. With such a diverse and large set of databases, it was impossible to clean all data of erroneous records. It is likely that for some species, larval records are shown, which may disturb the actual pattern, but this is rare and the overall pattern is clear. A very small lower threshold value was used, which helps to reduce the effect of small outliers for many species, but this also can make a species invisible during periods when it occurs in very low abundances. All in all, the phenology strips give a good view on seasonal fluctuations in abundance for the main flight time of each species. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 2 1

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Scientific names

How useful it would be if scientific names of hoverflies did not continually change, but they do. This book introduces some recently published name changes that have not appeared in previous keys. The fact that names change so often is (at least partly) a reflection of our increasing understanding of biodiversity. Cladistics, the process by which evolutionary trees are created and classifications refined, recently gained momentum through DNA research. In just a few years, DNA has become a prime source of information in the study of phylogenies and variation within and between species. This alternative approach to biodiversity, compared with traditional morphological research, can yield surprising insights. Cryptic species (species that can hardly be told apart morphologically but differ genetically) are revealed, but very different-looking species have also proven to be one species (though care is needed, as some distinct species – e.g. in Melanostoma or Neocnemodon – can have almost identical DNA, depending on which fragment of the DNA you are using). This type of research is rapidly becoming standard, but we are still in the middle of the process of re-evaluating current taxonomies, so further name changes can be anticipated.

Common names

Previous British field guides did not use common names for hoverflies. We think it is important to introduce them here. It has probably never been more important that hoverflies become popular amongst a wider audience to raise awareness of these flies, and insects in general, and we know common names do help. We have mainly relied on two existing sources that have proposed common names: the Field Guide to the Flower Flies of Northeastern North America (Skevington et al. 2019) and the excellent Flickr website of British entomologist Steven Falk (http://www.stevenfalk.co.uk). Although the former does not include many European species, it introduces common names for most of the genera found in the area this book covers. To standardise common names at the genus level for Europe and North America, we adopted most of them. The species names, therefore, are often a mix of the names proposed by Steven Falk and the American genus name. We realise common names may already exist regionally and that the new names may cause some controversy, but we feel our approach is the best way to bring about a standardised, consistent and widely used English nomenclature of hoverflies.

Geographical scope

This book contains all species of hoverflies that have been observed in the wild in the British Isles, Denmark, the Netherlands, Belgium and Luxembourg and will also work well for individuals observed in western Germany and northern France. Because the fauna of a region is constantly changing, it is quite a challenge to produce a key that will not become outdated in a few years. For instance, in the small and thoroughly investigated country of Belgium, over the last 12 years, 18 new species of hoverfly have been reported. These include: cryptic species that have been present there for some time but have only just been discovered as we have learned how to identify them; species that have recently expanded their distribution to Belgium; and species that have been newly described. Through intensive dialogue with top researchers in hoverflies, and implementing their latest taxonomic insights, and by gathering knowledge about the occurrence and ongoing range shifts of species from neighbouring regions, we have aimed to produce a guide that is at least current at the date of publication and that hopefully anticipates upcoming changes to the fauna of the geographical scope of this book. That said, we realise that sooner or later someone will make an unexpected discovery that we didn’t anticipate and – to be honest – we look forward to that too! We wish everyone good luck and lots of fun with this guide.

Right: Melangyna quadrimaculata (female) feeding on sallow pollen. 2 2 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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Keys Main key 1a Antennae short, much shorter than head 1b Antennae elongated, as long as or longer than head

à2 à Key 1 p. 24

2a Wing: crossvein r-m located before the middle of cell dm 2b Wing: crossvein r-m located in or after the middle of cell dm

à3 à5

3a Wing: cell r1 open; the fly is large or small 3b Wing: cell r1 closed; the fly is large, at least 11 mm.

à4 à Key 2 p. 28

4a Scutum and scutellum black or blackish; if hind margin of scutellum yellow, then abdomen without clear yellow markings 4b Scutellum paler than scutum, usually yellow; if only hind margin of scutellum is paler, abdomen with yellow markings

à Key 4 p. 64

5a Wing: vein R4+5 sinuous 5b Wing: vein R4+5 straight or nearly so

à Key 5 p. 86 à Key 6 p. 94

à Key 3 p. 30

Key 1 1a Abdomen black with bright yellow markings 1b Abdomen brown, black or red

à2 à 14

2a Abdomen cylindrical, black, with three equal narrow yellow bands 2b Abdomen wide, yellow marks not in the form of three equal narrow bands 3a Antennae placed on a frontal prominence 3b Frontal prominence absent 4a Hind half of scutellum black 4b Scutellum entirely yellow

à3 à5

à4 à Northern Saprun Wasp Fly Sphiximorpha subsessilis p. 223 à Common Wasp Fly Ceriana conopsoides p. 223 à Southern Wasp Fly Ceriana vespiformis p. 223

5a Tergites 2-4 with roughly equal yellow markings à6 5b Tergite 3 black or with yellow markings much smaller than those on tergites 2 and 4 à Two-banded Meadow Fly Chrysotoxum bicinctum p. 111 6a Yellow pairs of markings on tergites 3 and 4 do not reach the side margin, therefore side margin black; hind margin of tergites 3 and 4 black or narrowly yellow, if narrowly yellow, not connected with the yellow markings above it 6b Yellow pairs of markings on tergites 3 and 4 reach the side margin; hind margin of tergites 3 and 4 yellow, in the hind corner connected with the yellow markings above it

à7 à8

7a Fore and mid femora entirely yellow or only narrowly black at base; katepisternum usually with yellow spot à Hook-banded Meadow Fly Chrysotoxum festivum p. 111 7b At least basal fifth of fore and mid femora black; katepisternum usually black à Smooth-banded Meadow Fly Chrysotoxum vernale p. 111 8a Third antennal segment, measured from outer upper edge, as long as or longer than first antennal segment and second antennal segment combined 8b Third antennal segment, measured from outer upper edge, shorter than first antennal segment and second antennal segment combined

à9 à 12

9a Male: genitalia not very large. Female: tergite 6 without a median longitudinal keel. Third antennal segment, measured from outer upper edge, longer than first antennal segment and second antennal segment combined à 10 9b Male: genitalia strikingly large. Female: tergite 6 with a median longitudinal keel. Third antennal segment, measured from outer upper edge, as long as first antennal segment and second antennal segment combined à Large Meadow Fly Chrysotoxum cautum p. 109 2 4 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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crossvein r-m

cel 3 2a

1a

1b

3a

3b

4a

4b

crossvein r-m

cel 3

2b

1a

5a

1b

3a

5b

2a

2b

3b 4a

5a

5b

4b

6a

6b

8a 8b 7a

7b

♀ 9a

9b

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10a Abdomen with long hairs, hairs as long as or longer than width of hind tarsus  11 10b Abdomen with short hairs, except for anterior corners of tergite 2; hairs distinctly shorter than width of hind tarsus  Naked Meadow Fly Chrysotoxum lessonae p. 107 11a Smaller species; abdomen short and convex; scutellum yellow with black centre; anterior margin of wing not darkened  Little Meadow Fly Chrysotoxum arcuatum p. 109 11b Larger species; abdomen not so short and convex; scutellum black except yellow anterior part; anterior margin of wing darkened  Greater Meadow Fly Chrysotoxum fasciolatum p. 109 12a Black anterior band on tergites 3 and 4 runs continuously to side margin  13 12b Black anterior band on tergites 3 and 4 is broken just before side margin  Broken-banded Meadow Fly Chrysotoxum octomaculatum p. 113 13a Anterior margin of yellow markings on tergite 2 straight and parallel with anterior margin of tergite, except on outer sixth of their width, where they bend abruptly backwards. Therefore, band strongly widens towards side margin  Verrall’s Meadow Fly Chrysotoxum verralli p. 113 13b Anterior margin of yellow markings on tergite 2 convex, only roughly parallel with tergite anterior margin for at most half their width, curving gradually backwards. Yellow band not strongly widening towards side margin  Variable Meadow Fly Chrysotoxum elegans p. 113 14a Abdomen copper or bronze, without red markings 14b Abdomen largely red

 15  Vermillion Fly Psarus abdominalis p. 267

15a Arista implanted on base of upper surface of third antennal segment; eyes bare; wing vein R4+5 with an appendix into cell r4+5 (Ant flies Microdon; see Key 1A for identification of puparia) 15b Arista implanted on tip of antennae; eyes with hairs; wing vein R4+5 without an appendix

 16  18

16a Scutum with pale hairs only; posterior margin of scutellum straight or only slightly concave  17 16b Scutum with a band or two patches of black hairs between wing bases; posterior margin of scutellum between teeth distinctly concave  Chalk Ant Fly Microdon devius p. 105 17a Scutellum same colour as scutum, dark  Heath Ant fly Microdon analis / Large Ant Fly Microdon major p. 105 17b Scutellum usually paler than scutum, reddish  Bog Ant Fly Microdon myrmicae / Limestone Ant Fly Microdon mutabilis p. 107 18a Third antennal segment twice as long as first and second antennal segments combined; first antennal segment twice as long as second antennal segment 18b Third antennal segment as long as first and second antennal segments combined; first antennal segment as long as second antennal segment

 19  21

19a Underside of hind femur with a kink and excavation in which the hind tibia fits; tarsomere 3 of all legs dark; scutum dull  20 19b Hind femur of normal shape, cylindrical; tarsomere 3 of all legs pale; scutum shiny  Pine Longhorn Callicera rufa p. 219 20a Hairs on scutellum longer than first antennal segment; hairs on scutum and abdomen yellow–brown to grey–brown; in male, usually at least tergite 4 largely covered with black hairs; hind tibia often darkened at tip  Dark Longhorn Callicera fagesii p. 219 20b Most hairs on scutellum not longer than first antennal segment; hairs on scutum and abdomen orange to white–yellow; tergites usually without black hairs; all tibiae orange  Macquart’s Longhorn Callicera macquarti p. 219

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10a

10b

12a

12b

14b

14a

11a

11b

13a

13b

15a

15b

16b

16a

18a

17a

19a

18b

17b

♂

♂

20a

20b

19b

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21a Male: frons above antennae bare. Female: base of femora black  22 21b Male: frons above antennae with hairs along eyes, hairs as long as hairs on eyes. Female: femora yellow or only very base black  Ivy Longhorn Callicera spinolae p. 221 22a Scutum thinly but distinctly dusted greyish over almost entire surface, with or without two or four distinct longitudinal dust-stripes; scutellum with long hairs, hairs on posterior margin longer than scutellum, hairs on upper surface of scutellum two-thirds or more length of scutellum  Yellow Longhorn Callicera aenea p. 221 22b Scutum shiny, except anterior which has two longitudinal grey stripes of dusting that stop abruptly between wing bases; scutellum with short hairs, hairs on posterior margin shorter than scutellum, hairs on upper surface of scutellum not longer than half length of scutellum  Golden Longhorn Callicera aurata p. 221

Key 1A Ant flies Microdon puparia 1a Reticular pattern of ridges confined to sides, upper surface of puparium smooth, bald 1b All surfaces of puparium covered in reticular pattern of ridges

2 3

2a Reticulations at sides poorly defined; anterior spiracle longer than width at base; found in ant nests of the genus Myrmica  Bog Ant Fly Microdon myrmicae p. 107 2b Reticulations at the sides well defined; anterior spiracle shorter than width at base; found in ant nests of the genus Formica  Limestone Ant Fly Microdon mutabilis p. 107 3a Reticular pattern fine, space between ridges not bigger than diameter of posterior spiracle; anterior spiracle not curved 4 3b Reticular pattern coarse, space between ridges larger than diameter of posterior spiracle; anterior spiracle curved  Chalk Ant Fly Microdon devius p. 105 4a Anterior spiracle red–brown and almost three times longer than its maximum basal width; posterior spiracle high and narrow, almost conical; found in ant nests of the genus Lasius  Heath Ant fly Microdon analis p. 105 4b Anterior spiracle black–brown and at most twice as long as its maximum basal width; posterior spiracle short and wide; found in ant nests of the genus Formica  Large Ant Fly Microdon major p. 105

Key 2 Plumehorns Volucella 1a Fly does not look like a bumblebee 2 1b Thorax and abdomen covered in long dense hairs; fly looks like a bumblebee (different colour morphs)  Bumblebee Plumehorn Volucella bombylans p. 371 2a Tergites 3 and 4 black 2b Tergites 3 and 4 with orange or yellow bands

3 4

3a Tergite 2 ivory-white; side margins of scutum dark brown, sometimes dull orange; scutellum and at least posterior part of scutum with black hairs  Pied Plumehorn Volucella pellucens p. 373 3b Tergite 2 orange–yellow; side margins of scutum orange; scutum and scutellum with golden-yellow hairs  Orange-belted Plumehorn Volucella inflata p. 373 4a Tergite 2 with reddish pair of markings, tergite 3 with orange band, tergite 4 with yellow band; tip of abdomen yellow; sternite 2 black; scutum shiny  Hornet Plumehorn Volucella zonaria p. 371 4b Markings on abdomen uniformly yellow; tip of abdomen black; sternite 2 yellow; scutum dull  Wasp Plumehorn Volucella inanis p. 373

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21a

anterior side

21b

posterior side

1b

1a

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Key 3 1a Face yellow, often with a black central stripe 1b Face black 2a Very small flies, 4–7 mm; tergite 2 without large pair of whitish markings 2b Large flies, 9–11 mm; tergite 2 with large pair of whitish markings

2  11 3  Dark-saddled Hoary Leucozona laternaria p. 147 (see also Key 4, 32b)

3a Eyes with uniformly distributed hairs, not with vertical stripes of hairs; scutellum black 3b Eyes with vertical stripes of hairs; scutellum often with yellow posterior margin

4 6

4a Male genitalia: larger, causing sternite 4 to be constricted and shorter than sternite 3. Female: tergite 4 hairs uniformly white  5 4b Male genitalia: smaller; sternite 4 with straight hind margin and about as long as sternite 3. Female: posterior part of tergites 2–4 with black hairs  Common Grass Skimmer Paragus haemorrhous p. 213 5a Male genitalia: paramere boomerang shaped, inner side concave, without keel. Female: hairs on posterior part of tergites 2–4 erect, with a few semi-erect on hind margin  Heathland Grass Skimmer Paragus tibialis p. 213 5b Male genitalia: paramere triangular, inner side straight, with keel. Female: hairs on posterior part of tergites 2–4 adpressed  Constricted Grass Skimmer Paragus constrictus p. 213 6a Tergites 2 and 3 uniformly black or black with red markings 7 6b Tergites 2 and 3 with yellow markings  Yellow-banded Grass Skimmer Paragus quadrifasciatus p. 217 7a Abdomen black or with only few red markings on middle of tergites and that do not reach tergite side margin 7b Abdomen with extensive red markings, reaching side margin of at least tergite 3

8 9

8a Tergites 2–4 with silver dust bars underneath pale hairs (best seen by viewing from the side); abdomen usually black. Male genitalia: basolateral lobe with two teeth of equal size; paramere wide  Grey-banded Grass Skimmer Paragus pecchiolii p. 215 8b Tergites 2–4 without or with only faint dust bars; tergites 2 and 3 often with red spot. Male genitalia: lower tooth on basolateral lobe twice as big as upper one; paramere narrow  Red-dotted Grass Skimmer Paragus albifrons p. 215 9a Male genitalia: basolateral lobe with two teeth; outer upper border of hypandrium not extended into large triangular tooth. Female: tergite 7 usually with a shallow depression in middle; if absent, then central dark band on face occupies about one-quarter face width  10 9b Male genitalia: basolateral lobe with one tooth; outer upper border of hypandrium extended into large triangular tooth. Female: tergite 7 without a shallow depression in middle; central dark band on face occupies about one-quarter face width  Red Grass Skimmer Paragus testaceus p. 215 10a Male genitalia: with a long, pointed protrusion between hypandrium and lingula. Female: tergite 7 with a shallow depression in middle  Spiny Grass Skimmer Paragus finitimus p. 217 10b Male genitalia: without a long, pointed protrusion between hypandrium and lingula. Female: tergite 7 without a shallow depression in middle  Flaming Grass Skimmer Paragus flammeus p. 217 11a Abdomen not with combination of being very slender and constricted, anterior half not slenderer than scutellum  12 11b Abdomen very long and slender, anterior half even narrower than scutellum  Common Dainty Baccha elongata p. 211 12a Abdomen constricted at tergite 2; hind femur strongly swollen 12b Abdomen not constricted; hind femur usually not strongly swollen

 13  27

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13a Wing: vein M1 and crossvein dm-m with rounded angle 13b Wing: vein M1 and crossvein dm-m are bent at a sharp angle

 14  20

14a Sternite 1 present, wider than long; usually fore and mid tarsi more or less uniformly brown or yellow  15 14b Sternite 1 mostly reduced or absent, if present longer than wide; fore and mid tarsi with basal three tarsomeres yellow, strongly contrasting with outer two black tarsomeres  Variable Pufftail Sphegina sibirica p. 319 15a Lower half of face white–yellow, although mouth edge may be black 15b Face entirely black

 16  17

16a Humerus black, not contrasting with scutum; third antennal segment not very large; mouth edge usually black  Common Pufftail Sphegina clunipes p. 319 16b Humerus yellow, contrasting with black scutum; third antennal segment remarkably large; mouth edge usually yellow  Elegant Pufftail Sphegina elegans p. 319 17a Hind trochanter partly or entirely yellow 17b Hind trochanter black

 18  19

18a Wing: costa and subcosta join at level of crossvein r-m. Male genitalia: surstylus fairly short with blunt tip  Lesser Pufftail Sphegina verecunda p. 321 18b Wing: costa and subcosta join before crossvein r-m. Male genitalia: surstylus elongated with pointed tip  Red-horned Pufftail Sphegina nigra p. 321 19a Katepisternum shiny; fore and mid legs largely yellow or yellow–brown; face below antennae hollowed out. Male genitalia: surstylus with very wide base abruptly narrowing to tip  Shiny Pufftail Sphegina montana p. 323 19b Katepisternum dusted; fore and mid legs black, except knees and sometimes basal third of tibiae yellow; abdomen relatively short and broad; face below antennae not hollowed out. Male genitalia: surstylus elongated, curved, with slightly wider base  Stocky Pufftail Sphegina spheginea p. 321 20a Wing: crossvein dm-m and apical part of vein M1 darkened 20b Wing: crossvein dm-m and apical part of vein M1 not darkened

 21  24

21a Tergite 4 black; third antennal segment at least twice longer than wide  22 21b Sides of tergite 4 with pair of small yellow markings; third antennal segment at most 1.5 times longer than wide  Many-spotted Fen Fly Neoascia interrupta p. 323 22a Tergite 2 usually with yellow markings; fore femur yellow or with faint brown ring  23 22b Tergite 2 black; fore femur with a clear wide black ring  Single-banded Fen Fly Neoascia unifasciata p. 327 23a Yellow pair of markings on tergite 2 with more or less straight posterior margin; plates behind hind coxae just touch  Smudge-veined Fen Fly Neoascia podagrica p. 327 23b Yellow pair of markings on tergite 2 with oblique anterior and posterior margins, resembling an inverted V; plates behind hind coxae widely separated  Butterbur Fen Fly Neoascia obliqua p. 327 24a Tarsomeres 4 and 5 of fore tarsus yellow; third antennal segment at least 1.5 times longer than wide  25 24b Tarsomeres 4 and 5 of fore tarsus black; third antennal segment barely longer than wide  Short-horned Fen Fly Neoascia geniculata p. 323 25a Tip of hind femur black or slightly dark orange; plates behind hind coxae connected; tergite 2 with yellow markings, sometimes missing in female. Female: abdomen constricted between tergite 1 and 2  26 25b Tip of hind femur bright yellow; plates behind hind coxae widely separated; tergite 2 black. Female: abdomen constricted halfway along tergite 2  Yellow-kneed Fen Fly Neoascia meticulosa p. 325

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26a Tergites 2 and 3 uniformly black or black with yellow markings that do not reach side margins; mouth edge distinctly protruding. Male: tergite 8 with pale hairs. Female: tergite 2 gradually widening  Black-kneed Fen Fly Neoascia tenur p. 325 26b Tergites 2 and 3 with yellow bands that reach side margins over its full width; mouth edge slightly protruding. Male: tergite 8 with black hairs. Female: tergite 2 constricted halfway  Broad-banded Fen Fly Neoascia annexa p. 325 27a Face with facial tubercle and/or mouth edge protruding; face not entirely covered in long drooping shaggy hairs 27b Face flat, sloping backwards, without facial tubercle and without protruding mouth edge; face entirely covered in long drooping shaggy hairs

 28  Key 3A

28a Wing: vein M1 meets vein R4+5 only just before wing-tip 28b Wing: vein M1 meets vein R4+5 well before wing-tip

 29  32

29a Abdomen partly orange 29b Abdomen black

 30  31

30a Male: face with narrow black median stripe from mouth edge up to the facial tubercle; orange markings on tergite 3 usually reaching posterior margin. Female: black median stripe on tergite 2 widest near tergite posterior margin, but narrows abruptly just before posterior margin itself; groove on frons wider, reaching anterior ocellus  Orange-belted Spineleg Myolepta dubia p. 301 30b Male: face with strongly widening black shining median stripe from mouth edge to well over facial tubercle; if orange markings on tergite 3 present, not reaching posterior margin. Female: black median stripe on tergite 2 blends into a black transverse line along tergite posterior margin; groove on frons narrow, ending just before anterior ocellus  Small-spotted Spineleg Myolepta potens p. 301 31a Sides of thorax shiny; metasternum with hairs. Male: face with strongly widening black shining median stripe from mouth edge to well over facial tubercle  Dark Spineleg Myolepta vara p. 303 31b Sides of thorax dusted; metasternum bare. Male: face with short narrow black median stripe  Obscure Spineleg Myolepta obscura p. 303 32a Eyes with long hairs; face without facial tubercle 32b Eyes with hairs or bare; if eyes hairs present, then facial tubercle also present

 33  35

33a Hind femur in middle at most 1.5 times wider than mid femur. Male genitalia: epandrium not elongated, about as long as wide. Female: posterior anepisternum with black hairs  34 33b Hind femur distinctly thickened, in middle 2–3 times wider than mid femur. Male genitalia: epandrium elongated, almost 1.5 times longer than wide. Female: posterior anepisternum with white hairs  Pine Haireye Psilota atra p. 357 34a Male: hind coxa and lower part of katepisternum with white hairs. Genitalia: surstylus not remarkably long and slender. Female: hair fringe under scutellum black, with hairs shorter than hairs on tergite 3; hairs on posterior margin of tergite 4 two times longer than hairs on anterior part of tergite  Anthracine Haireye Psilota anthracina p. 357 34b Male: hind coxa and lower part of katepisternum with black hairs. Genitalia: surstylus remarkably long and slender. Female: hair fringe under scutellum white or mixed black and white, with hairs approximately as long as hairs on tergite 3; tergite 4 without long hairs on posterior margin  Spindly Haireye Psilota exilistyla p. 357 35a Face without orbital strip; if abdomen entirely black, often centre dull 35b Face with orbital strip, a hairy strip on face along eye, from height of antenna to mouth edge; abdomen usually uniformly black

 36  Key 3B

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27a

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36a Small stocky species; abdomen uniformly black, sometimes with blue or green sheen; abdomen usually dull in middle with shiny side margins; face with or without facial tubercle. Female: frons with transverse grooves  37 36b Abdomen usually narrow; abdomen with red, yellow or blue–grey markings; if abdomen uniformly black, abdomen elongated and shiny; face with facial tubercle. Female: frons without transverse grooves  Key 3C 37a Tergites entirely metallic, with greenish sheen, centre not dull. Male: eyes separated 37b Tergites metallic with black, blue or greenish sheen; if with greenish sheen, centre dull. Male: eyes meet on frons

 38  39

38a Fore tarsus and third antennal segment black; anterior anepisternum bare  Green Shimmer Lejogaster metallina p. 313 38b Fore tarsus and usually also mid tarsus with central tarsomeres orange; base of third antennal segment orange; anterior anepisternum with hairs in upper posterior corner  Splendid Shimmer Lejogaster tarsata p. 313 39a Wing: apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance 39b Wing: apical part of vein M1 not recurrent and ends at vein R4+5 in an acute or right angle, so cell r4+5 not rectangular

 40  46

40a Legs entirely black 40b At least knees of legs orange

 41  42

41a Third antennal segment rounded. Male: eyes meet, with length of contact similar to ocellar triangle length. Female: posterior margin of tergites 4 and 5 without tubercle or notch  Atlantic Mucksucker Orthonevra brevicornis p. 315 41b Third antennal segment about twice as long as wide. Male: eyes barely meet. Female: middle of posterior margin of tergite 4 with a small tubercle; middle of posterior margin of tergite 5 with a small notch  Slim-horned Mucksucker Orthonevra nobilis p. 315 42a Eyes without dark horizontal band; third antennal segment at most three times as long as wide  43 42b Eyes with a dark horizontal band; third antennal segment four times as long as wide  Stripe-eyed Mucksucker Orthonevra elegans p. 313 43a At least basal third of tibiae orange 43b Only very base of tibiae orange

 44  Nordic Mucksucker Orthonevra erythrogona p. 315

44a Wing: pterostigma uniformly yellowish; crossvein r-m not darkened; face narrow  45 44b Wing: pterostigma bicoloured, yellow with dark-brown spot at base; crossvein r-m darkened; face wide  Willow Mucksucker Orthonevra geniculata p. 317 45a Male genitalia: surstylus wide and with a notch halfway, aedeagus with short projection. Female: side margins of sternite 8 convex; sternite 8 bare in middle  Mire Mucksucker Orthonevra intermedia p. 317 45b Male genitalia: surstylus narrow and without notch, aedeagus with long projection. Female: side margins of sternite 8 angled; middle of sternite 8 with hairs  Stackelberg’s Mucksucker Orthonevra stackelbergi p. 317 46a Anterior part of scutum without two grey–white dusted longitudinal stripes; sternite 1 dull; body with green or black sheen  47 46b Anterior part of scutum with two grey–white dusted longitudinal stripes; sternite 1 shiny; body with green sheen  Stripe-backed Glimmer Riponnensia splendens p. 311 47a Third antennal segment largely orange 47b Third antennal segment entirely dark

 48  52

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37a 36b

37b 38a cell r4+5

38b

cell r4+5

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48a Wing: basal veins yellow, contrasting with grey veins in apical half 48b Wing: basal veins dark, not contrasting with rest of wing

 49  50

49a Proepimeron dusted; face at level of antennae distinctly wider than an eye. Female: body shiny black  Yellow-winged Wrinklehead Chrysogaster cemiteriorum p. 311 49b Proepimeron shiny; face at level of antennae about as wide as an eye. Female: body shiny blue  Blue Wrinklehead Chrysogaster basalis p. 311 50a Male: face at level of antennae about twice as wide as an eye; upper side scutellum with long hairs, hairs about as long as on scutum. Female: body shiny green; face at level of antennae wider than an eye  51 50b Male: face at level of antennae about as wide as an eye; upper side of scutellum almost bare. Female: body shiny, dark purple; face at level of antennae narrower than an eye  Dark-winged Wrinklehead Chrysogaster solstitialis p. 309 51a Face wide. Male: facial tubercle distinct. Female: scutum bare  Green Wrinklehead Chrysogaster virescens p. 309 51b Face very wide. Male: facial tubercle indistinct. Female: scutum with short white hairs  Broad-faced Wrinklehead Chrysogaster rondanii p. 309 52a Eyes meet; fly is a male 52b Eyes widely separated; fly is a female 53a Male: tergite 8 with long hairs 53b Male: tergite 8 with short hairs

 53  57  54  Naked Wrinklehead Melanogaster nuda p. 303

54a Male: hairs on scutum black; hairs on hind tibia mostly black 54b Male: hairs on scutum usually, at least in anterior part, partly pale; hairs on hind tibia mostly yellow

 55  56

55a Male: facial tubercle distinct; tip of surstylus bent inwards, pointing sideways  Dark Wrinklehead Melanogaster aerosa p. 305 55b Male: facial tubercle indistinct; tip of surstylus much less bent, more or less pointing forward  Chalk Wrinklehead Melanogaster parumplicata p. 307 56a Male: hairs on scutum long; scutum dusted. Male genitalia: surstylus abruptly narrowed near tip  Common Wrinklehead Melanogaster hirtella p. 305 56b Male: hairs on scutum short; scutum centrally shiny. Male genitalia: surstylus parallel-sided, curved only at very tip  Hidden Wrinklehead Melanogaster curvistylus p. 307 57a Female: scutum with distinct hairs; abdomen upper surface with dull area, entire margins shiny  58 57b Female: scutum almost bare; entire abdomen shiny black  Naked Wrinklehead Melanogaster nuda p. 303 58a Female: scutum with short hairs; hairs on hind tibia mostly black  59 58b Female: scutum with fairly long erect hairs; hairs on hind tibia mostly yellow  Common Wrinklehead Melanogaster hirtella p. 305 (the female of Hidden Wrinklehead Melanogaster curvistylus remains undescribed but probably ends up here as well) 59a Female: angle between face and mouth edge sharply defined 59b Female: angle between face and mouth edge rounded

 Dark Wrinklehead Melanogaster aerosa p. 305  Chalk Wrinklehead Melanogaster parumplicata p. 307

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48a

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Key 3A 1a Tergites 2–4 about equal in size 2 1b Tergites 2 and 3 large; tergite 4 minute, hardly visible from above, although very rarely in some females half tergite 3 length  Mugwort Galleater Triglyphus primus p. 273 2a Anterior anepisternum with hairs; hard to see without a microscope 2b Anterior anepisternum bare; note, this is hard to see without a microscope

3 5

3a Third antennal segment long, at least twice as long as wide. Female: tergite 2 with a pair of spots 4 3b Third antennal segment short, about 1.5 times as long as wide. Female: abdomen uniformly black  Obscure Psyllid-killer Trichopsomyia joratensis p. 285 4a Wing: vein M1 perpendicular to R4+5. Female: diameter of the markings on tergite 2 smaller than distance between inner extremities of markings  Pale-footed Psyllid-killer Trichopsomyia flavitarsis p. 285 4b Wing: vein M1 ends in an acute angle on R4+5. Female: diameter of the markings on tergite 2 larger than distance between inner extremities of markings  Large-spotted Psyllid-killer Trichopsomyia lucida p. 285 5a Third antennal segment short, at most 1.5 times as long as wide 5b Third antennal segment long, at least twice as long as wide

6  19

6a Frons protrudes conically forward at level of antenna attachment. Male: mid coxa and hind trochanter without long spine. Female: frons with distinct dust markings 6b Frons of normal shape, not protruding conically forward at level of antenna attachment. Male: mid coxa and hind trochanter with long spine. Female: frons bare or with very small dust markings

7  15

7a Antennae attach above middle of head; abdomen not distinctly wide; abdomen usually either entirely black or with only one pair of pale markings 8 7b Antennae attach at middle of head; abdomen wide; abdomen usually with two pairs of pale markings  Four-spotted Pithead Pipiza quadrimaculata p. 279 8a Hind femur not swollen; underside of hind femur without groove or ridges on tip 8b Hind femur swollen; underside of hind femur with groove and ridges on tip

9  10

9a Male: fore tarsus usually yellow; sides of face below antenna attachment point divergent. Female: tergite 5 about as long as wide  Pale-footed Pithead Pipiza luteitarsis p. 279 9b Male: fore tarsus usually dark; sides of face below antenna attachment point parallel. Female: tergite 5 approximately twice as wide as long  Broad-faced Pithead Pipiza accola p. 279 10a Fore tarsus dark, or with basal tarsomeres yellow, but outer tarsomere always dark 10b Fore tarsus entirely yellow

 11  Poplar Pithead Pipiza festiva p. 281

11a Hind femur swollen, but underside near tip without extra bulge; third antennal segment usually longer than wide  12 11b Hind femur swollen, underside near tip with extra bulge; third antennal segment about as long as wide; thorax and abdomen with pale hairs  Big-thighed Pithead Pipiza austriaca p. 281 12a Wing without dark patch, or with dark patch with diffuse edges; third antennal segment 1–1.3 times longer than wide; hairs on face dark or pale  13 12b Wing with distinct and sharply defined dark patch; third antennal segment 1.3–1.5 times longer than wide; abdomen usually black, sometimes with a pair of indistinct yellow markings on tergite 2; hairs on face pale  Smudge-winged Pithead Pipiza lugubris p. 283 13a Abdomen black or with a pair of markings on tergite 2 only. Male: face with black hairs. Female: tergite 4 anteriorly with band of black hairs; sternite 3 black (best assessed in living specimens)  14 13b Abdomen with a pair of markings on tergite 2, almost always on tergite 3 as well. Male: face with pale hairs. Female: tergite 4 mostly with pale hairs; sternite 3 yellow (best assessed in living specimens)  Square-spot Pithead Pipiza fasciata p. 281

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14a Wing sometimes transparent, but usually with well-defined dark patch, in field, indistinguishable from species in 14b  Common Pithead Pipiza noctiluca p. 283 14b Wing transparent or sometimes with an ill-defined dark patch; in field, indistinguishable from species in 14a  Little Pithead Pipiza notata p. 283 15a Wing: cell bm and cell br entirely covered with microtrichia 15b Wing: at least half of cell bm and cell br without microtrichia. Females cannot be identified further

 16  17

16a Male: sternite 4 flat, without tubercle; underside of tarsomere 1 of fore tarsus with depression. Female: eyes with dense black hairs  Dark Spikeleg Neocnemodon pubescens p. 287 16b Male: sternite 4 with tubercle; tarsomere 1 of fore tarsus shaped normally. Female: eyes with sparse pale hairs  Warted Spikeleg Neocnemodon verrucula p. 287 17a Male: sternite 3 flat; tarsomere 1 of fore tarsus not swollen; mid tibia not strongly swollen  18 17b Male: sternite 3 with tubercle; tarsomere 1 of fore tarsus swollen; mid tibia strongly swollen  Big-ankled Spikeleg Neocnemodon latitarsis p. 289 18a Male: underside of tarsomere 1 of fore tarsus with depression; apical half of mid tibia with concavity  Pale-haired Spikeleg Neocnemodon vitripennis p. 289 18b Male: tarsomere 1 of fore and mid tarsi with tubercle; apical half of mid tibia with keel, keel with setae  Poplar Spikeleg Neocnemodon brevidens p. 291 19a Wing: vein M1 meets vein R4+5 at a right angle 19b Wing: vein M1 meets vein R4+5 at an acute angle

 20  Dark-haired Smoothleg Heringia heringi p. 291

20a Eyes meet on frons; fly is a male 20b Eyes separated; fly is a female

 21  27

21a Male: sternite 3 or 4 with a transverse elevation or tubercles 21b Male: sternites 3 and 4 normally shaped, flat

 22  23

22a Male: sternite 4 with two tubercles; wing transparent. Genitalia: epandrium large, with wide shoulders  Tubercled Flatface Pipizella pennina p. 277 22b Male: sternite 3 with transverse elevation; wing darkened in the middle. Genitalia: epandrium without wide shoulders  Smudge-winged Flatface Pipizella maculipennis p. 277 23a Male: fore and mid tarsi black, at most tarsomere 1 brown. Genitalia: surstylus not very wide at base and not more or less transparent  24 23b Male: fore and mid tarsi with basal two tarsomeres orange, strongly contrasting with remaining tarsomeres. Genitalia: surstylus very wide at base and more or less transparent  Pale-legged Flatface Pipizella annulata p. 275 24a Male genitalia different from description in 24b, rather, as described below  25 24b Male genitalia: epandrium large and more or less rectangular, with wide shoulders; shoulder flat and bent backwards, bearing a small surstylus  Broad Flatface Pipizella divicoi p. 273 25a Male: tergites 2–4 with many black hairs. Genitalia: epandrium not very small, surstylus shorter than epandrium  26 25b Male: tergites 2–4 covered largely with yellow hairs. Genitalia: epandrium very small, resulting in surstylus being longer than epandrium  Dry Flatface Pipizella zeneggenensis p. 277 26a Male: hind tibia with short hairs, about 1.3–1.5 times width of hind tibia. Genitalia: epandrium elongated owing to long epandrial arms; width of apical half of surstylus about a third surstylus length  Common Flatface Pipizella viduata p. 275 26b Male: hind tibia with long hairs, about twice the width of hind tibia. Genitalia: epandrial arms small or lacking, causing epandrium to be about square; width of apical half of surstylus less than one-fifth surstylus length  Hairy-legged Flatface Pipizella virens p. 275

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15a

15b

16a

17a

17b

19a

24b

18a

19b

22a

18b

21a

22b

25b

16b

23b

26a

26b

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With current knowledge, females cannot be identified further. Below we treat only the four more common species. 27a Female: tarsi dark, tarsomeres 1 and 2 of fore and mid leg can be pale, but not both bright yellow  28 27b Female: tarsomeres 1 and 2 of fore and mid tarsi yellow, brighter yellow and more contrasting with black parts compared to other Pipizella; third antennal segment long, about three times longer than wide  Pale-legged Flatface Pipizella annulata p. 275 28a Female: third antennal segment 1.5–2 times as long as wide; anterior surface of hind tibia with hairs not, or barely longer than, width of hind tibia; wing usually transparent  Common Flatface Pipizella viduata p. 275 28b Female: third antennal segment over twice longer than wide; anterior surface of hind tibia with hairs distinctly longer than width of hind tibia; wing often darkened in middle  29 29a Female: third antennal segment 2.5 times longer than wide; tergite 3 with pale hairs on axis  Hairy-legged Flatface Pipizella virens p. 275 29b Female: third antennal segment at least three times longer than wide; tergite 3 usually with black hairs on axis  Smudge-winged Flatface Pipizella maculipennis p. 277

Key 3B Blacklets Cheilosia and Garlic eater Portevinia 1a Eyes bare 1b Eyes with hairs

2  29

2a Legs partly pale, at least tibiae pale at both ends 2b Legs black, at most tibiae pale at base

3  14

3a Eyes separated; fly is a female; face with erect hairs, hairs at least longer than hairs on orbital strip, but note that sometimes only a few hairs present; orbital strip very wide 3b Fly is a male or a female; face bare, without erect hairs; orbital strip not very wide

4 5

4a Female: short, stocky species; underside of third antennal segment largely orange; hairs on scutellum short, adpressed, about half the length of hind tibia width  Hawkbit Blacklet Cheilosia latifrons p. 239 4b Female: a slenderer species; third antennal segment largely dark; hairs on scutellum long, at least as long as width of hind tibia  Sow-thistle Blacklet Cheilosia griseiventris p. 239 5a Facial tubercle widened, semicircular when viewed from above, occupying full width of face 5b Facial tubercle not widened, when viewed from above not occupying full width of face

6 7

6a Third antennal segment orange–brown to brown–black; anterior anepisternum bare  Bolete Blacklet Cheilosia scutellata p. 231 6b Third antennal segment bright orange; anterior anepisternum with hairs in upper posterior corner  Truffle Blacklet Cheilosia ruffipes p. 231 7a Arista with hairs, hairs longer than width of arista at base 7b Arista bare or with hairs shorter than width of arista at base

8 9

8a Fly is a male or a female; fore tarsus black or dark. Female: postpronotum and often posterior margin of scutellum yellowish  Heath Blacklet Cheilosia longula 8b Eyes separated; fly is a female; middle segments of fore tarsus pale; postpronotum and scutellum black  Fragile Blacklet Cheilosia mutabilis 9a Fly is a male or a female; femora partly black 9b Eyes separated; fly is a female; femora entirely yellow  Yellow-legged Blacklet Cheilosia flavipes 10a Wing without dark patch in middle; face not elongated 10b Wing with dark patch in middle; face elongated

p. 231 p. 247  10 p. 249

 11  Houseleek Blacklet Cheilosia caerulescens p. 239

11a Sternites shiny or lightly dusted; orbital strip and adjacent upper corners of face not with distinct long hairs  12 11b Sternites dull; upper half of orbital strip and adjacent corners of face with long white hairs  Large-horned Blacklet Cheilosia laticornis p. 229 12a Fly is a male or a female; at least some tarsomeres of fore and mid tarsi pale 12b Eyes separated; fly is a female; all tarsi black

 13  Hidden Blacklet Cheilosia clama p. 253

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1a

1b

4a

28b

28a

3a

4b

5a

6b

6a

3b

5b

7a 8a

10b

10a

11a

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13a Fly is a male or a female; sternites shiny. Female: third antennal segment very large and bright orange  Parsley Blacklet Cheilosia pagana p. 241 13b Eyes separated; fly is a female; sternites thinly dusted; third antennal segment not very large and with dark upper apical corner; eyes with short sparse hairs which can easily be missed  Silver-fronted Blacklet Cheilosia uviformis p. 261 14a Abdomen without pairs of grey dust spots; facial tubercle distinct  15 14b Abdomen with pairs of grey dust spots; face strongly protruding, facial tubercle indistinct; third antennal segment bright orange  Spotted Garlic Eater Portevinia maculata p. 225 15a Fly is a male or a female; wing base brown or black; fore tarsus black  16 15b Eyes separated; fly is a female; wing base yellow; middle tarsomeres of fore tarsus pale, but note that in some specimens this can be very indistinct  Buttercup Blacklet Cheilosia albitarsis p. 245 / Bulbous Buttercup Blacklet Cheilosia ranunculi p. 245 16a Sternites 2–4 shiny, usually contrasting with dusted sternite 1 16b Sternites 1–4 dusted

 17  22

17a Eyes meet on frons; fly is a male 17b Eyes separated; fly is a female

 18  20

18a Male: frons shiny 18b Male: frons dusted 19a Male: scutum coarsely punctate; tergite 4 with largely black hairs 19b Male: scutum finely punctate; tergite 4 with largely pale hairs

 19  Lady’s-mantle Blacklet Cheilosia vicina p. 235  Black-legged Blacklet Cheilosia nigripes p. 233  Primrose Blacklet Cheilosia antiqua p. 233

20a Female: scutum with adpressed hairs 20b Female: scutum with erect yellow hairs

 21  Primrose Blacklet Cheilosia antiqua p. 233

21a Female: posterior anepisternum shiny 21b Female: posterior anepisternum dusted

 Black-legged Blacklet Cheilosia nigripes p. 233  Lady’s-mantle Blacklet Cheilosia vicina p. 235

22a Eyes meet on frons; fly is a male 22b Eyes separated; fly is a female

 23  26

23a Male: all scutum hairs yellow 23b Male: scutum with both black and yellow hairs

 24  25

24a Male: frons dusted; dusting above facial tubercle gradually merges into dusted band below antennae; scutum finely punctate  Water Avens Blacklet Cheilosia pubera p. 237 24b Male: frons shiny; face around facial tubercle shiny, contrasting with dusted grey band below antennae; scutum coarsely punctate  Brassy Blacklet Cheilosia ahenea p. 237 25a Male: scutum shiny; frons lightly dusted 25b Male: scutum dusted; frons thickly dusted

 Bistort Blacklet Cheilosia sahlbergi p. 235  Dusted Blacklet Cheilosia grisella p. 237

26a Female: scutum hairs all same length, yellow  27 26b Female: scutum with hairs of two lengths, dense short yellow hairs and sparse long black hairs, intermixed  Bistort Blacklet Cheilosia sahlbergi p. 235 27a Female: face slightly dusted around facial tubercle; scutum finely punctate 27b Female: face shiny around facial tubercle; scutum coarsely punctate

 28  Brassy Blacklet Cheilosia ahenea p. 237

28a Female: posterior margin of scutellum with 4–6 bristles; antennae reddish brown; orbital strip narrower. Characters variable and identification from species 28b not always possible  Water Avens Blacklet Cheilosia pubera p. 237 28b Female: posterior margin of scutellum with two bristles or bristles absent; antennae black; orbital strip wider. Characters variable and identification from species in 28a not always possible  Dusted Blacklet Cheilosia grisella p. 237 29a Face with erect hairs, hairs longer than hairs on orbital strip 29b Face bare, without erect hairs

 30  38

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13a

15b

14b

13b

19a

18a

16b

16a

18b

19b

20a

23a

20b

23b

24a

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26b 25a

27a

25b

27b

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30a Wing without dark patch; hairs on base of abdomen not white, on centre of abdomen black, and on tip orange–red  31 30b Wing with distinct dark patch; body with long dense hairs; base of abdomen with white hairs, centre with black hairs and tip with orange–red hairs  Bumblebee Blacklet Cheilosia illustrata p. 229 31a Not with combination of: face below antennae wider than an eye, and legs black except tibiae pale at base  32 31b Face very wide, below antennae wider than an eye; legs black, except base of tibiae pale, distinct in the female, less distinct in the male  Bearded Spruce Blacklet Cheilosia morio p. 227 32a Legs partly pale, with at least tibiae pale at base 32b Legs entirely black

 33  Figwort Blacklet Cheilosia variabilis p. 241

33a Bristles on posterior margin of scutellum absent 33b Bristles on posterior margin of scutellum present

 34  35

34a Short, stocky species; underside of third antennal segment orange. Male: frons lightly dusted, contrasting with denser dusting on face. Female: hairs on scutellum short, adpressed, about as long as half hind tibia width  Hawkbit Blacklet Cheilosia latifrons p. 239 34b Slender species; third antennal segment entirely dark. Male: frons and face both densely dusted, without contrast between them. Female: hairs on scutellum long, at least as long as width of hind tibia  Sow-thistle Blacklet Cheilosia griseiventris p. 239 35a Bristles on posterior margin of scutellum long, at least as long as scutellum length; fore and mid tibiae pale at both ends  36 35b Bristles on posterior margin of scutellum short, shorter than scutellum length; only base of fore and mid tibiae narrowly pale  Plantain Blacklet Cheilosia lasiopa p. 241 36a Underside of third antennal segment orange. Female: upper part of occiput shiny 36b Third antennal segment entirely brown–black or black. Female: occiput dusted

 37  Stocky Blacklet Cheilosia vulpina p. 243

37a Upper and lower hair patches on katepisternum connected. Male: abdomen without dust spots; frons not swollen. Female: third antennal segment large; hairs on scutum semi-erect  Parsnip Blacklet Cheilosia barbata p. 243 37b Upper and lower hair patches on katepisternum widely separated. Male: abdomen with dust spots; frons swollen. Female: third antennal segment small; hairs on scutum erect  Kingcup Blacklet Cheilosia frontalis p. 243 38a Legs black or at most middle tarsomeres or base of tibiae pale 38b Legs partly pale, at least tibiae pale at both ends

 39  46

39a Eyes meet on frons; fly is a male; fore tarsus with middle tarsomeres pale 39b Fly is a male or a female; tarsi black

 40  41

40a Male: wing base brown; tarsomere 5 of fore tarsus rectangular. Genitalia: surstylus wide, with high keel covered with microtrichia  Buttercup Blacklet Cheilosia albitarsis p. 245 40b Male: wing base yellowish; tarsomere 5 of fore tarsus narrowing towards tip. Genitalia: surstylus narrow, with low keel without microtrichia  Bulbous Buttercup Blacklet Cheilosia ranunculi p. 245 41a Wing base dark 41b Wing base yellow 42a Abdomen with pairs of grey dusted spots 42b Abdomen without pairs of grey dusted spots

 42  Yellow-winged Blacklet Cheilosia impressa p. 245  43  44

43a Eyes meet on frons; fly is a male; legs black, except narrowly pale knees; eyes with pale hairs  Leafmining Blacklet Cheilosia semifasciata p. 225 43b Fly is a male or a female; about one-third of base of tibiae pale; eyes with dark hairs  Garlic Blacklet Cheilosia fasciata p. 225 44a Fly is a male or a female; third antennal segment orange at least below; shiny black or blue–black species  45 44b Eyes separated; fly is a female; third antennal segment entirely brown–black or black; brown–green shiny species  Leafmining Blacklet Cheilosia semifasciata p. 225

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31b

30b

33a

34a

35a

33b 34b

36a

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37b

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39a 36b

41a

40a

42a

41b

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45a Face narrow, below antennae much narrower than an eye  Sooty Blacklet Cheilosia carbonaria p. 259 45b Face very wide, below antennae wider than an eye  Spruce Blacklet Cheilosia luteicornis p. 227 Note that female Bearded Spruce Blacklet Cheilosia morio sometimes has only inconspicuous hairs on face, and the key will lead to this species too 46a Bristles on posterior margin of scutellum absent 46b Bristles on posterior margin of scutellum present 47a Underside of third antennal segment, at least, orange 47b Third antennal segment entirely black 48a Body with orange–yellow or yellow hairs; wing transparent or darkened 48b Body with fox-red hairs; wing darkened at crossveins r-m and bm-m

 47  58  48  Greater Spring Blacklet Cheilosia grossa p. 249  49  Foxy Blacklet Cheilosia chrysocoma p. 229

49a Lower half of eyes bare; hairs on posterior anepisternum with wavy tip; large species, 13–15 mm 49b Eyes entirely covered with hairs, if lower half of eyes bare, hairs on posterior anepisternum straight

 50  51

50a Spring species; hairs on arista about half as long as diameter of arista. Male: tarsomere 5 of fore tarsus usually dark. Female: posterior margin tergite 3 with a sparse, incomplete band of adpressed hairs; posterior third of tergite 4 with scattered, semi-adpressed hairs  Spring Butterbur Blacklet Cheilosia himantopus p. 251 50b Summer species; hairs on arista at least as long as diameter of arista. Male: fore tarsus usually entirely yellow. Female: posterior margin tergite 3 with complete band of dense, adpressed hairs; posterior third of tergite 4 with dense, adpressed hairs  Summer Butterbur Blacklet Cheilosia canicularis p. 251 51a Hind tibia with a distinct black ring in middle 51b Hind tibia entirely orange or with black smudge 52a Arista black 52b Arista orange at base 53a Hairs on eyes very long; face narrow 53b Hairs on eyes not very long; face wide

 52  54  53  Cabbage Thistle Blacklet Cheilosia chloris p. 253  Wood Blacklet Cheilosia lenis p. 247  Hidden Blacklet Cheilosia clama p. 253

54a Arista black; wing transparent; face narrow, below antennae not wider than an eye  55 54b Arista dark orange; wing darkened at crossveins r-m and bm-m and on apical half; face wide, below antennae wider than an eye  Smudge-winged Blacklet Cheilosia nebulosa p. 253 55a Fly is a male or a female. Male: frons largely or entirely covered with black hairs  56 55b Eyes meet on frons; fly is a male; frons largely or entirely covered with yellow hairs  Yellow-legged Blacklet Cheilosia flavipes p. 249 56a Hairs on posterior anepisternum straight. Male: posterior part of scutum with at least some black hairs. Female: femora largely black  57 56b Hairs on posterior anepisternum with wavy tip. Male: scutum and abdomen hairs all pale. Female: femora orange  Lesser Spring Blacklet Cheilosia albipila p. 249 57a Medium-sized species, 8–10 mm. Male: upper side of middle tarsomeres of fore tarsus black or dark Female: hairs on scutum short and adpressed  Orange-shinned Blacklet Cheilosia fraterna p. 255 57b Large species, 12–15 mm. Male: upper side of middle tarsomeres of fore tarsus pale. Female: hairs on scutum long and erect  Early Butterbur Blacklet Cheilosia orthotricha p. 251 58a Sternites shiny. Female: tergites 2–4 without oblique patches of longer silver–grey hairs 58b Sternites distinctly dusted. Female: tergites 2–4 with oblique patches of longer silver–grey hairs

 59  69

59a Hairs on eye not very long; upper and lower hair patches on katepisternum widely separated  60 59b Hairs on eye very long, longer than hairs on orbital strip; upper and lower hair patches on katepisternum connected  Wood Blacklet Cheilosia lenis p. 247 60a Hairs on upper half of eye pale or brown; eyes with hairs all over or lower part of eyes bare 60b Hairs on upper half of eye black or blackish; eyes with hairs all over

 61  67

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45a

48a 47a 46a

46b

47b 48b

52a

49a

49b

50a

50b

52b

54a ♂

53a

♀

53b 54b

55a

55b

59a

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58a

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61a Hind leg black or only base of tibia narrowly yellow; hairs on arista longer than or as long as width of arista at base; third antennal segment usually entirely black 61b Hind tibia with base and tip distinctly orange; arista bare or length of hairs less than width of arista at base; underside of third antennal segment usually pale

 62  63

62a Fly is a male or a female. Female: central tarsomeres of fore leg pale; eyes with sparse short hairs  Fragile Blacklet Cheilosia mutabilis p. 247 62b Eyes separated; fly is a female; fore tarsus black; eyes with dense long hairs  Leafmining Blacklet Cheilosia semifasciata p. 225 63a Third antennal segment about 1.5 times as long as wide, ranging from dark orange to brown–black; small, slender species 63b Third antennal segment about as long as wide, usually largely bright orange

 64  65

64a Basal half of claws orange. Male genitalia: gonostylus with long dorsal projection  Pale-clawed Blacklet Cheilosia urbana p. 257 64b Claws brown–black. Male genitalia: gonostylus with short dorsal projection  Dark-clawed Blacklet Cheilosia psilophthalma p. 257 65a Sternites shiny. Male: frons shiny 65b Sternites weakly dusted. Male: frons dusted

 66  Silver-fronted Blacklet Cheilosia uviformis p. 261

66a Hind tibia with black ring. Male: bristles on posterior margin of scutellum longer than other hairs on scutellum. Female: underside of hind femur with bristle-like hairs; abdomen not short and wide  Ragwort Blacklet Cheilosia bergenstammi p. 255 66b Hind tibia orange without black ring, at most with black smudge. Male: bristles on posterior margin of scutellum absent or shorter than other hairs on scutellum. Female: underside of hind femur without bristle-like hairs; abdomen short and wide  Orange-shinned Blacklet Cheilosia fraterna p. 255 67a Male: abdomen not narrow; tergite 4 in centre near posterior margin with erect or semi-erect hairs. Female: abdomen widest at posterior corner of tergite 2; frons not narrow  68 67b Male: abdomen narrow, parallel-sided; tergite 4 in centre near posterior margin with adpressed hairs. Female: abdomen widest at posterior corner of tergite 3; frons narrow  Sooty Blacklet Cheilosia carbonaria p. 259 68a In living specimens, scutum with black shine; hairs on scutum varying from yellow to black; orbital strip not both wide and dusted. Male: tergite 8 shiny. Female: strip between eye margin and lateral longitudinal grooves narrow and finely punctate  Yarrow Blacklet Cheilosia vernalis p. 259 68b In living specimens, scutum with blue shine; scutum covered largely with black hairs; orbital strip wide and dusted. Male: tergite 8 dusted. Female: strip between eye margin and lateral longitudinal grooves wide and densely punctate  Blue Blacklet Cheilosia cynocephala p. 259 69a Anterior anepisternum bare in upper posterior corner 69b Anterior anepisternum with hairs in upper posterior corner

 70  Mullein Blacklet Cheilosia aerea p. 261

70a Underside of third antennal segment orange to reddish brown, at least clear reddish 70b Underside of third antennal segment black to blackish brown, in some specimens paler, but not clear reddish

 71  73

71a Facial tubercle distinct, face between facial tubercle and mouth edge distinctly concave. Male: tergites 2 and 3 with pale hairs in centre  72 71b Facial tubercle indistinct, face between facial tubercle and mouth edge almost vertical. Male: tergites 2 and 3 with field of black hairs in centre just before posterior margin  Chinless Blacklet Cheilosia velutina p. 265 72a Sternites lightly dusted; hind femur usually without black ring; upper and lower hair patches on katepisternum distinctly separated  Silver-fronted Blacklet Cheilosia uviformis p. 261 72b Sternites densely dusted; hind femur with distinct black ring; upper and lower hair patches on katepisternum connected  Knotweed Blacklet Cheilosia rufimana p. 265 73a A smaller species, 7–9 mm; anteroventral hair fringe on hind femur short, in male shorter than anterodorsal hair fringe, in female anteroventral hair fringe absent, occasionally with single longer hairs which are shorter than, or rarely as long as, the diameter of hind femur. Male genitalia: dorsal lobe of gonostylus with a more or less distinct hook on its dorsal margin; inner side of surstylus in ventral view straight. Female: underside of hind femur tip usually without black bristles or spines  Dull-bellied Blacklet Cheilosia proxima p. 263 73b A larger species, (7) 9–12 mm; anteroventral hair fringe on hind femur long, as long as or longer than anterodorsal hair fringe, in female obviously longer than diameter of hind femur. Male genitalia: dorsal lobe of gonostylus simple; inner side of surstylus in ventral view concave. Female: underside of hind femur tip with some black bristles or spines  Greater Dull-bellied Blacklet Cheilosia gigantea p. 263 5 2 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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72a

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Key 3C 1a Smaller species, usually less than 10 mm; abdomen slender and markings different than described in 1b 2 1b Larger species, up to 13 mm; abdomen widely oval and flattened, with typical semicircular markings  Migrant Flatbelly Xanthandrus comtus p. 211 2a Lower half of face protruding forwards; third antennal segment distinctly large 3 2b Lower half of face usually not extending forwards or, if extending forwards, face with distinct facial tubercle and mouth edge and third antennal segment not distinctly large 6 3a Arista attached just after middle of third antennal segment 3b Arista attached on upper outer corner of third antennal segment 4a Anterior anepisternum bare 4b Anterior anepisternum with pale hairs

4  Common Bighorn Fly Pelecocera tricincta p. 273 5  Dune Bighorn Fly Pelecocera lugubris p. 271

5a Markings on abdomen large and orange; hind margin of lunule shiny, triangular part between antennae dusted  Orange-spotted Bighorn Fly Pelecocera scaevoides p. 271 5b Markings on abdomen small and grey-dusted; lunule entirely shiny  Silver-spotted Bighorn Fly Pelecocera caledonica p. 271 6a If abdomen with yellow markings, not as described in 6b; face and scutellum black 7 6b Tergites 2–4 with yellow or whitish, narrow triangular spots with pointed inner side, which are sometimes fused to a narrow band; face and/or scutellum sometimes partly yellow  Needle Roundtail Meligramma cingulata p. 117 (see also Key 4B, 2b) 7a Abdomen largely orange or with distinctive yellow markings on tergite 3 (sometimes on tergite 4 as well) 7b Abdomen with a different pattern, usually with paired spots on tergites 2–4

8 9

8a Abdomen largely orange  Hornhand Sedgesitter Pyrophaena granditarsa p. 211 8b Abdomen with distinctive yellow markings on tergite 3, sometimes also with smaller markings on tergite 4  Fourspot Sedgesitter Pyrophaena rosarum p. 209 9a Eyes meeting on frons; fly is a male 9b Eyes separated; fly is a female

 10  41

10a Male: fore leg normally shaped, fore tibia and fore tarsus not distinctly widened, fore tibia at most widening twice from base to tip 10b Male: fore tibia and/or fore tarsus distinctly widened

 11  18

11a Male: fore femur with a striking black curled hair at tip 11b Male: fore femur without curled hair at tip

 12  14

12a Male: abdomen narrow, with grey or yellow spots 12b Male: abdomen very narrow, entirely black, without grey spots

 13  Needle Sedgesitter Platycheirus immaculatus p. 207

13a Male: abdomen with dense grey-dusted spots; posterior surface of fore femur with bristle-like hairs before curled hair; haltere dark  Blackthorn Sedgesitter Platycheirus ambiguus p. 207 13b Male: abdomen with yellowish, weakly dusted spots; posterior surface of fore femur with longer and only slightly thickened hairs before curled hair; haltere yellow  Curlyhair Sedgesitter Platycheirus transfugus p. 207

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1a

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14a Male: abdomen with orange–yellow spots; metasternum strongly reduced in middle, diamond-shaped, genus Melanostoma  15 14b Male: abdomen with grey spots; metasternum wide  Slender-handed Sedgesitter Platycheirus sticticus p. 195 15a Male: abdomen not very long and elongated; face shiny or only lightly dusted, with little or no contrast between face and shiny facial tubercle; arista almost bare, length of hairs less than half width of arista at base  16 15b Male: abdomen distinctly long and elongated; face dusted, contrasting clearly with shiny facial tubercle; arista with hairs, each about as long as width of arista at base  Long-winged Duskyface Melanostoma scalare p. 181 16a Male: hairs on anterior part of scutum short, about one-quarter scutellum length; abdomen with some black hairs; eyes meet in an angle of c. 80°–90°; frons shiny; face narrow  17 16b Male: hairs on anterior part of scutum long, at least one-third scutellum length; abdomen hairs pale; eyes meet in an angle of c. 85°–100°; frons dusted; face wide  Dark Duskyface Melanostoma certum p. 183 17a Male: scutum hairs usually mainly pale; sternite 2 no more than 1.25 times as long as its maximum width. Genitalia: postgonite usually short, a little longer than wide  Variable Duskyface Melanostoma mellinum p. 181 17b Male: scutum hairs usually mainly black; sternite 2 at least 1.5 times as long as its maximum width. Genitalia: postgonite usually long, about two times longer than wide  Intermediate Duskyface Melanostoma mellarium p. 183 18a Male: fore tibia not widening or only slightly so 18b Male: fore tibia distinctly widening 19a Male: abdomen with orange–yellow spots; face protruding 19b Male: abdomen with grey spots; face not protruding

 19  23  20  Broad-fronted Sedgesitter Platycheirus discimanus p. 209

20a Male: fore tarsus with basal two tarsomeres widened, remainder of tarsomeres not widened; abdomen slender  21 20b Male: fore tarsus with basal three tarsomeres widened in decreasing width, two apical tarsomeres not widened; abdomen wide, with orange spots, these on tergite 2 small or absent  Stocky Sedgesitter Platycheirus melanopsis p. 209 21a Male: scutum shiny; mouth edge protruding, but not beyond facial tubercle; spots on abdomen small  22 21b Male: scutum dusted; mouth edge protruding beyond facial tubercle; spots on abdomen large  Dull-backed Sedgesitter Platycheirus manicatus p. 205 22a Male: hind tibia with tuft of black hairs; tarsomere 1 of fore tarsus distinctly widened  Shiny-backed Sedgesitter Platycheirus tarsalis p. 205 22b Male: hind tibia without tuft of black hairs; tarsomere 1 of fore tarsus only slightly widened  Fragile Sedgesitter Platycheirus complicatus p. 203 23a Male: fore femur with two striking tufts of black hairs near base 23b Male: fore femur without two striking tufts of black hairs near base

 24  27

24a Male: middle trochanter with long spine; tarsomere 2 of fore tarsus four times wider than long  25 24b Male: middle trochanter without long spine; tarsomere 2 of fore tarsus 1–2 times wider than long  Grey-spotted Sedgesitter Platycheirus albimanus p. 195 25a Male: frons shiny, blackish, distinctly contrasting with grey-dusted face  26 25b Male: both frons and face dusted grey, without contrast between the two  Many-tufted Sedgesitter Platycheirus scutatus p. 197 26a Male: tergite 2 usually with small spots, rarely absent; inner side of mid tibia, from base not with dense, regular row of pale hairs of similar length, but with scattered hairs as long as half tibia width  Splendid Sedgesitter Platycheirus splendidus p. 197 26b Male: tergite 2 usually black, rarely with small spots; spots on tergites 3 and 4 small, slightly oblique, located close to anterior margin; inner side of mid tibia, from base to well over halfway with dense, regular row of pale hairs of similar length, hairs as long as width of tibia  Small-spotted Sedgesitter Platycheirus aurolateralis p. 199 27a Male: underside of third antennal segment pale 27b Male: third antennal segment entirely black

 28  31

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15a

14b

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17a

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28a Male: only tarsomere 1 of fore tarsus strongly widened; underside of fore femur with a row of black bristles  29 28b Male: tarsomeres 1 and 2 of fore tarsus strongly widened; underside of fore femur with a row of thinner and longer hairs  Wood Sedgesitter Platycheirus parmatus p. 199 29a Male: underside of mid tibia without or with a moderate swelling at tip, base of swelling without longer hairs directed towards base of tibia  30 29b Male: underside of mid tibia abruptly swollen near tip, base of swelling with hairs directed towards base of tibia  Nielsen’s Sedgesitter Platycheirus nielseni p. 201 30a Male: underside of mid tibia near base with tuft of short black and yellow hairs; posterior side of mid tibia just beyond middle without black tuft directed towards tibia tip  White-spotted Sedgesitter Platycheirus peltatus p. 201 30b Male: underside of mid tibia near base with tuft of long black hairs; posterior side of mid tibia just beyond middle with black tuft directed towards tibia tip  Northern Broadhand Sedgesitter Platycheirus amplus p. 203 31a Male: spots on abdomen very large, spots on tergite 4 producing narrow black posterior stripe or stripe absent; tergite 5 largely yellow 31a Male: spots on abdomen smaller, producing broad black posterior stripe on tergite 4; tergite 5 uniformly black or with faint yellow markings 32a Male: fore tibia gradually widening from base to tip 32b Male: fore tibia abruptly widening in basal half

 32  35

 33  Orange-legged Sedgesitter Platycheirus fulviventris p. 193

33a Male: posterior side fore femur with a row of 4–6 black bristles  34 33b Male: posterior side fore femur with dense mainly pale hairs; abdomen largely yellow  Yellowcomb Sedgesitter Platycheirus perpallidus p. 193 34a Male: posterior side fore femur near base without long white bent bristle; lower half of posterior anepisternum shiny, contrasting with dull upper half  Blackspine Sedgesitter Platycheirus scambus p. 191 34b Male: posterior side fore femur near base with long white bent bristle; posterior anepisternum entirely dull  Comb-legged Sedgesitter Platycheirus immarginatus p. 191 35a Male: fore tibia gradually widening towards tip 35b Male: fore tibia abruptly widening in distal half

 36  Variable Sedgesitter Platycheirus podagratus p. 189

36a Male: tergite 2 with small spots; posterior side fore femur near base with long white bent bristle  37 36b Male: tergite 2 with large spots; posterior side fore femur near base without long white bent bristle; posterior side fore femur with a row of six black bristles  Blackspine Sedgesitter Platycheirus scambus p. 191 37a Male: fore femur at base with discrete black markings that are not connected with each other  38 37b Male: fore femur at base continuously black on all sides  Dusky Sedgesitter Platycheirus occultus p. 185 38a Male: abdomen not distinctly slender; anterior and posterior anepisternum dusted  39 38b Male: abdomen distinctly slender; spots on tergite 3 elongated; posterior anepisternum shiny, anterior anepisternum dusted  Slender Sedgesitter Platycheirus angustatus p. 187 39a Male: black hairs on posterior side of fore femur not bent near tip; underside tarsomere 1 of fore tarsus with V-shaped groove  40 39b Male: black hairs on posterior side of fore femur bent near tip; underside tarsomere 1 of fore tarsus with longitudinal groove ending in a pit  Common Sedgesitter Platycheirus clypeatus p. 185 40a Male: black hairs on posterior side of fore femur extending to near tip; V-shaped groove on underside tarsomere 1 of fore tarsus in apical half, but near middle  Long Sedgesitter Platycheirus europaeus p. 187 40b Male: black hairs on posterior side of fore femur absent in apical half; V-shaped groove on underside tarsomere 1 of fore tarsus near tip  Bare-legged Sedgesitter Platycheirus ramsarensis p. 189 41a Female: abdomen entirely black 41b Female: abdomen with pairs of grey, yellow or orange spots 42a Female: legs partly pale 42b Female: legs black

 42  45  43  Black Halfband Melangyna quadrimaculata p. 119

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28b 29a

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43a Female: abdomen slender 43b Female: abdomen very slender

 44  Needle Sedgesitter Platycheirus immaculatus p. 207

44a Female: metasternum strongly reduced in middle, diamond-shaped (see image at 45a)  Dark Duskyface Melanostoma certum p. 183 44b Female: metasternum wide (see image at 45b)  Melanistic form of a Platycheirus. Often difficult to identify further because of the lack of markings on the abdomen; if abdomen with very faint dusted grey bands, see P. ambiguus 45a Female: spots on abdomen more or less triangular, or spots very small and rounded; metasternum strongly reduced, genus Melanostoma 45b Female: spots on abdomen not triangular; metasternum not reduced, genus Platycheirus

 46  48

46a Female: face shiny or only lightly dusted, with little or no contrast between face and shiny facial tubercle; arista seemingly bare, length of hairs less than half width of arista at base  47 46b Female: face dusted, contrasting clearly with shiny facial tubercle; arista with hairs, each about as long as width of arista at base  Long-winged Duskyface Melanostoma scalare p. 181 47a Female: spots on abdomen more or less triangular, sometimes spots reduced; frons with lateral dust spots only, remainder of frons shiny; abdomen partly with black hairs; frons and face narrow  Variable Duskyface Melanostoma mellinum p. 181 or Intermediate Duskyface Melanostoma mellarium p. 183 47b Female: abdomen usually black, sometimes with small round spots; anterior part of frons dusted over full width; abdomen entirely covered with pale hairs; frons and face wide  Dark Duskyface Melanostoma certum p. 183 48a Female: spots on abdomen grey 48b Female: spots on abdomen yellow to red 49a Female: tergites 3 and 4 with a pair of distinctly grey dusted spots 49b Female: tergites 3 and 4 with a faintly dusted band

 49  52  50  Blackthorn Sedgesitter Platycheirus ambiguus p. 207

50a Female: underside of third antennal segment orange; abdomen with three pairs of spots  51 50b Female: third antennal segment entirely black; abdomen with four pairs of spots  Broad-fronted Sedgesitter Platycheirus discimanus p. 209 51a Female: frons with grey dust spots; face dusted except facial tubercle shiny  Grey-spotted Sedgesitter Platycheirus albimanus p. 195 51b Female: frons and face shiny, only eye margin narrowly dusted  Slender-handed Sedgesitter Platycheirus sticticus p. 195 52a Female: underside of third antennal segment orange 52b Female: third antennal segment entirely black

 53  58

53a Female: abdomen with three pairs of spots; spots on tergite 2 small 53b Female: abdomen with four pairs of spots; spots on tergite 2 often large

 54  55

54a Female: face distinctly narrower than an eye; fore and mid tarsi at least largely yellow; basal half of cell bm bare  Many-tufted Sedgesitter Platycheirus scutatus / Splendid Sedgesitter Platycheirus splendidus / Small-spotted Sedgesitter Platycheirus aurolateralis 54b Female: face wide, slightly wider than an eye; fore and mid tarsi dark; cell bm only with bare spot at base  Curlyhair Sedgesitter Platycheirus transfugus

p. 197 p. 197 p. 199 p. 207

55a Female: fore and mid femora yellow, at most with brown smudge; underside of katepisternum with short hairs; spots on tergites 3 and 4 not rectangular  56 55b Female: fore and mid femora with a broad black ring; underside of katepisternum with long hairs; spots on tergites 3 and 4 large and rectangular  Wood Sedgesitter Platycheirus parmatus p. 199 56a Female: tergite 2 with large, almost rhomboid, spots that reach anterior margin  57 56b Female: tergite 2 with small, lunuler to triangular spots that do not reach anterior margin (identification uncertain, character might also occur in species of 57a and 57b)  Northern Broadhand Sedgesitter Platycheirus amplus p. 203 6 0 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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45a

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57a Female: mid tibia normal shape, sometimes with slight swelling near tip  White-spotted Sedgesitter Platycheirus peltatus p. 201 57b Female: mid tibia with constriction in apical part, followed by a swelling at tip  Nielsen’s Sedgesitter Platycheirus nielseni p. 201 58a Female: face protruding; base of fore femur largely black 58b Female: face not protruding; fore femur yellow or with reduced black markings 59a Female: vertex shiny; frons shiny with dust spots; scutum shiny 59b Female: vertex and frons entirely dusted; scutum dusted

 59  62

 60  Dull-backed Sedgesitter Platycheirus manicatus p. 205

60a Female: tergite 2 with small spots not reaching anterior margin of tergite  61 60b Female: tergite 2 with large spots reaching anterior margin of tergite  Shiny-backed Sedgesitter Platycheirus tarsalis p. 205 61a Female: tergites 3 and 4 with spots not reaching anterior margin of tergite  Fragile Sedgesitter Platycheirus complicatus p. 203 61b Female: tergites 3 and 4 with spots that reach anterior margin of tergite  Stocky Sedgesitter Platycheirus melanopsis p. 209 62a Female: tergites 5 and 6 with large pairs of spots 62b Female: tergite 5 with a small pair of spots, tergite 6 usually black or with a small faint pair of spots

 63  66

63a Female: hind femur and hind tibia usually entirely yellow; tergites 3 and 4 with narrow black posterior stripe 63b Female: hind femur and hind tibia usually with black ring in middle; tergites 3 and 4 posteriorly with wider black stripe

 64  65

64a Female: third antennal segment large and angular; dusting on frons behind lunule faint or absent  Orange-legged Sedgesitter Platycheirus fulviventris p. 193 64b Female: third antennal segment smaller and less angular; dusting on frons behind lunule distinct and connected to dusting along eyes  Yellowcomb Sedgesitter Platycheirus perpallidus p. 193 65a Female: tergite 2 with large spots; posterior side of fore femur near base without long white bent bristle  Blackspine Sedgesitter Platycheirus scambus p. 191 65b Female: tergite 2 with small spots; posterior side of fore femur near base with long white bent bristle  Comb-legged Sedgesitter Platycheirus immarginatus p. 191 66a Female: abdomen with four pairs of spots; anterior and posterior anepisternum dusted  67 66b Female: abdomen with three pairs of spots; abdomen narrow and pointed; posterior anepisternum shiny, anterior anepisternum dusted  Slender Sedgesitter Platycheirus angustatus p. 187 67a Female: hind femur largely or entirely black, at most very base and tip yellow 67b Female: hind femur largely yellow at base and tip

 68  70

68a Female: black hairs on posterior side of fore femur extending to near tip; tergite 2 square or a little wider than long; fore and mid tarsi entirely yellow  69 68b Female: hairs on posterior side of fore femur absent in apical half; tergite 2 distinctly wider than long; usually some tarsomeres of fore and mid tarsi dark  Bare-legged Sedgesitter Platycheirus ramsarensis p. 189 69a Female: fore femur with yellow base and tip; tergites 3 and 4 with rectangular markings  Long Sedgesitter Platycheirus europaeus p. 187 69b Female: fore femur black at base, only tip yellow; abdomen with rounded spots  Variable Sedgesitter Platycheirus podagratus p. 189 70a Female: spots on tergites 3 and 4 reaching anterior margin of tergites; vertex dusted or shiny  71 70b Female: spots on tergites 3 and 4 not reaching anterior margin of tergites; vertex shiny  Dusky Sedgesitter Platycheirus occultus p. 185 71a Female: vertex dusted; tergites 3 and 4 with large spots occupying one-half to two-thirds of tergite’s length; abdomen not elongated. Wing: cell bm entirely covered with microtrichia  Common Sedgesitter Platycheirus clypeatus p. 185 71b Female: vertex shiny, contrasting with dusted occiput; tergites 3 and 4 with small spots occupying one-half of tergite’s length; abdomen elongated. Wing: cell bm with bare spot at base  Long Sedgesitter Platycheirus europaeus p. 187

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57b

60a

60b

63a

65a

69a

58a

59a

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61a

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Key 4 1a Abdomen red or orange–brown 1b Abdomen coloured otherwise

2  20

2a Face greatly elongated, with pointed snout 2b Face not so elongated, without pointed snout

3 8

3a Eyes meet on frons; fly is a male 3b Eyes separated; fly is a female

4 6

4a Male: scutellum yellow to dark brown, exceptionally black; at most, basal half of femora black; arista bare or with hairs shorter than width of arista at base 5 4b Male: scutellum black; femora almost entirely black, at most tip pale; arista covered with hairs longer than width of arista at base  Forest Snout Fly Rhingia borealis p. 269 5a Male: hind tibia with a distinct black ring in middle; tergites 2–4 with black side margins and usually also black posterior margin; tergites 3–4 usually with dark central longitudinal stripe  Common Snout Fly Rhingia campestris p. 269 5b Male: hind tibia orange; tergites 2–4 orange, at most posterior margin narrowly black  Orange Snout Fly Rhingia rostrata p. 269 6a Female: hind femur largely or entirely orange; hind tibia orange or darkened only on tip 7 6b Female: hind femur largely black at base; hind tibia with dark ring in middle  Common Snout Fly Rhingia campestris p. 269 7a Female: arista bare or with hairs shorter than width of arista at base; at least underside of hind tarsus largely orange  Orange Snout Fly Rhingia rostrata p. 269 7b Female: arista with hairs, each longer than width of arista at base; hind tarsus mainly black  Forest Snout Fly Rhingia borealis p. 269 8a Wing: vein M1 meets vein R4+5 at an acute angle, just before wing-tip 8b Wing: vein M1 meets vein R4+5 at a right angle, well before wing-tip

9  Aspen Logsitter Hammerschmidtia ferruginea p. 293

9a Thorax mainly reddish brown; scutum upper surface may be grey, but margins and area before scutellum reddish brown 9b Thorax grey, contrasting with red–brown abdomen

 10  14

10a Arista with long hairs, hairs much longer than width of arista at base 10b Arista with short hairs, hairs not much longer than width of arista at base

 11  13

11a Smaller species, 5–8 mm; face only moderately protruding; upper part of katepisternum bare; posterior margin of posterior anepisternum with at most 3–5 black bristles  12 11b Large species, 8–11 mm; face strongly protruding; upper part of katepisternum with long white hairs; posterior margin of posterior anepisternum with 4–10 black bristles  Greater Sapeater Brachyopa vittata p. 293 12a Tergites 2–4 with dark edges and dark central longitudinal stripe; hairs on arista about three times longer than width of arista at base; face moderately protruding. Wing: cell dm in posterior corner with extension, extension one-tenth of length of crossvein dm-m  Conifer Sapeater Brachyopa testacea p. 293 12b Abdomen uniformly orange–brown; hairs on arista about two times longer than width of arista at base; face slightly protruding. Wing: cell dm in posterior corner with extension, extension one-quarter length of crossvein dm-m  Pale Sapeater Brachyopa obscura p. 295 13a Posterior margin of scutellum without black bristles; especially in female, sensory pit large, distance between ventral margin of third antennal segment and sensory pit smaller than diameter of sensory pit itself; wing-tip and false vein darkened. Male genitalia: lingula long and narrow  Beech Sapeater Brachyopa panzeri p. 295 13b Posterior margin of scutellum almost always with black bristles; sensory pit small, distance between ventral margin of third antennal segment and sensory pit larger than diameter of sensory pit itself; wing clear. Male genitalia: lingula short and wide  Smallpit Sapeater Brachyopa dorsata p. 295

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2b

1b

4a

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8a

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14a Arista with hairs as long as or longer than width of arista at base 14b Arista almost bare, if hairs present, much shorter than width of arista at base

 15  16

15a Postpronotum reddish brown, remainder of scutum grey; sensory pit large and kidney shaped; tergite 2 with black hairs in posterior corners  Pale-shouldered Sapeater Brachyopa scutellaris p. 297 15b Scutum including postpronotum grey; sensory pit small and round; tergite 2 entirely or almost entirely covered with yellow hairs  Dark-shouldered Sapeater Brachyopa pilosa p. 297 16a Sensory pit absent or rudimentary and smaller than width of arista; fore tarsus black and yellow; scutellum without transverse groove; notopleuron with pale hairs  17 16b Sensory pit clearly present, at least as large as width of arista; fore tarsus black; scutellum with transverse groove; notopleuron with black hairs  Dark-saddled Sapeater Brachyopa bicolor p. 297 17a Scutum without pair of shiny black markings near transverse suture 17b Scutum with pair of shiny black markings near transverse suture

 18  19

18a Fore tarsus almost entirely dark brown to black; lower part of face rather strongly protruding; proepimeron bare; vertex dusted; mediotergite entirely dusted  Mealy Sapeater Brachyopa insensilis p. 299 18b Fore tarsus with tarsomeres bicoloured, basal part yellow, apical part dark brownish; lower part of face only weakly protruding; proepimeron anteriorly with a few long pale hairs; vertex shiny diagonally behind ocelli and in space between ocelli; lower part of mediotergite shiny  Forest Sapeater Brachyopa grunewaldensis p. 299 19a At least centre of ocellar triangle without microtrichia, shiny black; hair fringe under scutellum present; over half of sternites 3 and 4 shiny; face slightly protruding  Broadleaf Twinspot Sapeater Brachyopa silviae p. 301 19b Ocellar triangle densely covered with microtrichia, not shiny; hair fringe under scutellum absent; sternites entirely shiny; face moderately protruding  Conifer Twinspot Sapeater Brachyopa bimaculosa p. 301 20a Body not with long and dense hairs; not a bumblebee mimic 20b Body covered in dense long hairs, abdomen without clear markings; a bumblebee mimic 21a Side margins of scutum bright yellow, strongly contrasting with dark remainder of scutum 21b Scutum without bright yellow side margins, at most side margins dull yellow 22a Abdomen not very long and slender 22b Abdomen very long and slender 23a Scutellum yellow with black base; abdomen flat and not constricted 23b Scutellum red; abdomen convex and constricted at tergite 2

 21  Bear Fly Eriozona syrphoides p. 147  22  28  23  Key 4A Globetails Sphaerophoria p. 76

 24  Phantom Potterfly Doros profuges p. 177

24a Eyes bare; abdomen with paired yellow spots  25 24b Eyes with hairs; tergites 3–4 with yellow bands that can be interrupted in middle  Crossband Dayglower Xanthogramma laetum p. 177 25a Spots on tergite 2 distinctly wider than spots on tergites 3 and 4; hind femur and hind tibia with dark markings  26 25b Spots on tergites 2–4 roughly same width; legs entirely orange-yellow  Barred Dayglower Xanthogramma citrofasciatum p. 177 26a Side of thorax with three or four yellow markings; microtrichia on membrane between tergites and sternites 3 and 4 yellow, best assessed in living specimens  27 26b Side of thorax with one or two yellow markings; microtrichia on membrane between tergites and sternites 3 and 4 black  Superb Dayglower Xanthogramma pedissequum p. 179

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27a Wing-tip transparent; inner side of markings on tergite 2 rounded. Male: yellow markings on tergite 2 bent forward near posterior corner; anterior margin of black band on sternite 2 pointed in middle  Stackelberg’s Dayglower Xanthogramma stackelbergi p. 179 27b Wing-tip from vein R4+5 anteriorly faintly darkened; inner side of markings on tergite 2 pointed. Male: yellow markings on tergite 2 widest near side margin, not bent forward near posterior corner; anterior margin of black band on sternite 2 straight or rounded in middle  Smoky-winged Dayglower Xanthogramma dives p. 179 28a Tergite 2 with a wide, whitish or blue-grey band which can be narrowly interrupted in middle; abdomen without yellow markings  29 28b Tergite 2 without a wide, whitish or blue-grey band; abdomen usually with yellow markings  33 29a Wing with distinct dark marking 29b Wing transparent

 30  31

30a Tergites 3 and 4 mainly with white hairs; anterior margin of scutellum black  Blotch-winged Whitebelt Leucozona lucorum p. 145 30b Tergites 3 and 4 with black hairs; scutellum yellow  Black-haired Whitebelt Leucozona inopinata p. 145 31a Eyes with hairs 31b Eyes bare 32a Scutellum yellow; fore tibia and fore tarsus yellow 32b Scutellum largely black; fore tibia partly and fore tarsus entirely black

 32  Whitebelt Smoothtail Epistrophe leiophthalma p. 155  Pale-saddled Hoary Leucozona glaucia p. 147  Dark-saddled Hoary Leucozona laternaria p. 147

33a Wing: vein R4+5 with a dip into cell r4+5 33b Wing: vein R4+5 almost straight, without a dip into cell r4+5

 34  43

34a Markings on tergites 3 and 4 both oblique with straight anterior margin 34b Markings on tergites 3 and 4 different

 35  37

35a Knob haltere black; face with black median stripe 35b Knob haltere yellow; face yellow, at most facial tubercle dark

 36  Pale-knobbed Lucent Didea fasciata p. 143

36a Abdomen with yellow markings. Male: frons yellow. Female: tergite 5 with yellow markings  Dark-knobbed Lucent Didea intermedia p. 143 36b Abdomen with fluorescent green markings in living specimens, yellow in pinned specimens. Male: frons with black markings around lunule. Female: tergite 5 black  Green Lucent Didea alneti p. 143 37a Tergites 3 and 4 with yellow bands 37b Abdomen with pairs of white or yellow spots

 38  39

38a Large, robust species, with wide abdomen; wing completely covered in microtrichia  Great Banded Gossammer Megasyrphus erraticus p. 145 38b Smaller species with slender abdomen; wing largely bare in basal half  Scaeva mecogramma p. 159

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39a Eyes with hairs 39b Eyes bare

 40  Bow-veined Aphideater Lapposyrphus lapponicus p. 159

40a Posterior margin of spots on tergite 3 parallel to the posterior margin of the tergite 40b Spots on tergite 3 oblique

 41  42

41a Spots on tergites 3 and 4 usually do not reach side margin. Male: eyes meet at an obtuse angle, over 150°. Female: frons slightly swollen, convex in profile, but difference with species of 41b subtle  Yellow-bowed Smoothwing Scaeva selenitica p. 157 41b Spots on tergites 3 and 4 usually reach side margin. Male: eyes meet at a right or slightly obtuse angle, 90°–106°. Female: frons not swollen, in profile flat or slightly concave, but difference with species in 41a subtle  Southern Smoothwing Scaeva dignota p. 157 42a Paired spots on tergites 3 and 4 narrow, anterior margin of spots distinctly concave; markings on abdomen white in living specimens  White-bowed Smoothwing Scaeva pyrastri p. 157 42b Paired spots on tergites 3 and 4 wide, anterior margin of spots almost straight; markings on abdomen yellow  Large-spotted Smoothwing Scaeva albomaculata p. 159 43a Eyes bare or with hairs, if hairs present, not in vertical stripes; larger species, almost always larger than 6 mm  44 43b Eyes with vertical stripes of hairs; very small species, c. 6 mm; scutellum usually with yellow posterior margin  Yellow-banded Grass Skimmer Paragus quadrifasciatus p. 217 44a Face with black median stripe; tergites 3 and 4 with yellow bands 44b Not with combination of face with black median stripe and tergites 3 and 4 with yellow bands 45a Hind tibia entirely black or more or less distinctly yellow only at base 45b Hind tibia with a wide, sometimes faint, black ring, base and tip yellow

 45  48

 46  Pine Bristleside Parasyrphus relictus p. 135

46a Hind femur with yellow tip; hind tibia normally yellow in basal third; underside of third antennal segment, at least, orange; fore and mid tarsi yellow or darkened  47 46b Hind leg black, only knees sometimes paler; antennae black; all tarsi black  Dark-legged Bristleside Parasyrphus lineola p. 135 47a Scutum shiny. Male: fore and mid tarsi dark. Female: base of hind femur black  Smudge-faced Bristleside Parasyrphus malinellus p. 131 47b Scutum dull. Male: fore and mid tarsi yellow. Female: base of hind femur yellow  Yellow-footed Bristleside Parasyrphus annulatus p. 133 48a Tergites 3 and 4 with bands; abdomen wide; sternites without black bands, at most with faint spots in middle  49 48b Tergites 3 and 4 with bands or spots, if with bands, abdomen elongated and/or sternites with distinct black bands or markings  61 49a Third antennal segment black 49b Underside of third antennal segment, at least, pale

 50  51

50a Frons above lunule black; posterior margin scutellum with black hairs; base of femora narrowly black  Black-horned Smoothtail Epistrophe grossulariae p. 149 50b Frons above lunule yellow; scutellum with yellow hairs; femora entirely yellow  Pale-sided Smoothtail Epistrophe diaphana p. 151 51a Posterior margin of spots on tergite 2 bent inwards just before side margin; scutum dull; either hind femur for over basal half black or entirely yellow, if entirely yellow then fore tarsus black 51b Posterior margin of spots on tergite 2 parallel to posterior margin of tergite; scutum dull or shiny; hind femur usually entirely yellow, if basal half black (rarely), fore tarsus yellow or dark but not black

 52  55

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52a Mouth edge yellow; yellow band on tergite 3 with more or less straight anterior margin; upper surface of lower calypter with hairs; anterior anepisternum bare  53 52b Mouth edge black; anterior margin of yellow band on tergite 3 with pointed centre; upper surface of lower calypter bare; anterior anepisternum with hairs  Black-footed Bristleside Parasyrphus nigritarsis p. 131 53a Eyes bare 53b Eyes with hairs

 54  Hairy-eyed Flower Fly Syrphus torvus p. 127

54a Upper side of hind femur at tip with adpressed black hairs. Female: hind femur yellow  Common Flower Fly Syrphus ribesii p. 129 54b Upper side of hind femur at tip with mainly adpressed yellow hairs. Female: at least basal half of hind femur black  Black-thighed Flower Fly Syrphus vitripennis p. 129 55a At least one-third of scutellum with black hairs 55b Scutellum with yellow hairs

 56  57

56a Arista black; scutum shiny, only margins covered with microtrichia. Female: frons with dust spots along eye margin, spots almost meeting, but always some shiny parts anterior to, between or posterior to the dust spots; vertex shiny; upper part of frons black to just before lunule, lower part yellow  Dark-backed Smoothtail Epistrophe nitidicollis p. 149 56b Arista orange; scutum thinly dusted, largely covered with microtrichia. Female: frons entirely dusted; vertex dusted; more of frons black, up to lunule  Olga’s Smoothtail Epistrophe olgae p. 149 57a Face not very wide; clypeus wide. Male: eyes meet at a right angle, at most 100°. Female: frons without sharp division between black and yellow  58 57b Face wide; clypeus narrow. Male: eyes meet at an obtuse angle, c. 107°. Female: frons with sharp V-shaped division between black upper part and yellow lower part  Broad-faced Smoothtail Epistrophe ochrostoma p. 153 58a Frons partly yellow, although sometimes hard to judge due to dense dusting; tergites 3 and 4 with wide bands; tergite 5 yellow or with triangular black spot in middle; hind tibia yellow. Male: at most, basal two-fifths of hind femur black  59 58b Frons entirely black, black continues down to next to lunule; tergites 3 and 4 with narrow bands; tergite 5 with black band occupying at least three-quarters tergite width. Male: at least basal half of hind femur black; hind tibia usually with a vaguely defined black ring on middle  60 59a Mouth edge partly or entirely black; posterior margin of yellow band on tergite 4 undulating; scutum shiny  Black-mouthed Smoothtail Epistrophe melanostoma p. 153 59b Mouth edge yellow; posterior margin of yellow band on tergite 4 straight with little notch in middle; scutum dull  Yellow-mouthed Smoothtail Epistrophe flava p. 153 60a Face wide; at least base of arista yellow; genae and sides of lower part of face with yellow hairs; anterior side of hind femur with black hairs on at most one-third of tip; anterior side of hind tibia with mix of black and yellow hairs  Wavy-banded Smoothtail Epistrophe cryptica p. 151 60b Face less wide; arista black; genae and usually sides of lower part of face with numerous black hairs; anterior side of hind femur mainly or entirely covered with yellow hairs; anterior side of hind tibia with yellow hairs  Dark Smoothtail Epistrophe obscuripes p. 151 61a Scutum anteriorly with two white or three grey longitudinal dust stripes 61b Scutum anteriorly without longitudinal dust stripes

 62  63

62a Markings on abdomen variable but unmistakable: tergites 3 and 4 with two orange bands, divided by two black bands  Marmalade Hoverfly Episyrphus balteatus p. 115 62b Tergites 3 and 4 with oblique yellow markings that usually meet in middle  Stripe-backed Brusheye Dasysyrphus albostriatus p. 137

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63a Pale markings on tergite 3 much wider than those on tergite 4, markings on tergite 4 sometimes even lacking 63a Pale markings on tergite 3 and 4 of roughly equal width 64a Tergite 2 with small pair of spots; eyes with hairs 64b Tergite 2 with large pair of spots; eyes bare

 64  65

 Yellow-girdled Brusheye Dasysyrphus tricinctus p. 137  Spring Smoothtail Epistrophe eligans p. 155

65a Eyes with hairs; abdomen wide; tergites 3 and 4 with pairs of hooked bars 65b Eyes bare, at most with sparse hairs, but in that case, abdomen slender

 66  72

66a Pale markings on tergites 3 and 4 reach side margin 66b Pale markings on tergites 3 and 4 do not reach side margin

 67  70

67a Underside of third antennal segment pale; pale markings on tergites 3 and 4 not strongly constricted in middle  68 67b Third antennal segment entirely black; pale markings on tergites 3 and 4 strongly constricted in middle, sometimes markings divided to create four spots per tergite  Hook-banded Brusheye Dasysyrphus friuliensis p. 137 68a Face with black median stripe 68b Face yellow, at most brownish at facial tubercle

 69  Yellow-faced Brusheye Dasysyrphus hilaris p. 139

69a Hind tibia with black ring in middle; pterostigma brown; sternite 2 with dark oval spot not reaching side margin. Female: frons with distinct dust spots  Broad-barred Brusheye Dasysyrphus venustus p. 139 69b Hind tibia yellow; pterostigma yellow; sternite 2 with dark band occupying full width, reaching side margin. Female: frons with indistinct dust spots  Narrow-barred Brusheye Dasysyrphus neovenustus p. 139 70a Third antennal segment entirely brown–black to black; scutellum with black hairs  71 70b Underside of third antennal segment orange; scutellum largely or entirely covered with yellow hairs  Lesser Brusheye Dasysyrphus pauxillus p. 141 71a Sternite 2 with black oval spot not reaching side margin  Black-spotted Brusheye Dasysyrphus pinastri p. 141 71b Sternite 2 with black rectangular band occupying full width, reaching side margin  Lena’s Brusheye Dasysyrphus lenensis p. 141 72a Tergites 3 and 4 with yellow spots, anterior margin of spots more or less straight and parallel to anterior margin of tergite, posterior margin more or less arc-shaped; spots on tergite 3 sweep up to anterior corners of tergite 72b Tergites 3 and 4 with bands or spots; if with spots, these spots not with straight anterior margin and arc-shaped posterior margin

 73  75

73a Face with black median stripe and black mouth edge; sternites with triangular black marks in centre; upper surface of lower calypter bare  74 73b Face yellow, mouth edge black; sternites with black bands; upper surface of lower calypter with hairs  Barred Flower Fly Syrphus nitidifrons p. 127 74a Pterostigma yellow–brown; arista pale, short, with thickened base. Male: eyes with short and sparse hairs. Female: eyes nearly bare  Common Spotted Bristleside Parasyrphus punctulatus p. 133 74b Pterostigma dark brown; arista black, long and narrow. Male: eyes with short but dense hairs. Female: eyes with sparse hairs  Greater Spotted Bristleside Parasyrphus macularis p. 133 75a Abdomen elongated, with parallel sides; abdomen with bands or pairs of spots, if with pairs of spots, anterior margin of spots on tergite 3 and 4 straight and parallel to anterior margin of tergite  Key 4B p. 80 75b Abdomen wider; abdomen with bands or pairs of spots, if with pairs of spots, anterior margin of spots on tergite 3 and 4 not parallel to anterior margin of tergite  Key 4C Aphideaters Eupeodes p. 82

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Key 4A Globetails Sphaerophoria 1a Scutum with yellow sides from postpronotum to transverse suture, thereafter black, although postalar callus often slightly yellow 1b Scutum with continuous bright yellow sides, although less distinct behind transverse suture 2a Antennae yellow, at most tip dark 2b Antennae black 3a Face yellow, at most facial tubercle dark 3b Face with dark median stripe, from antennae to mouth edge

3  Saltmarsh Globetail Sphaerophoria loewi p. 175  Rueppell’s Globetail Sphaerophoria rueppelli p. 175  Stripe-faced Globetail Sphaerophoria shirchan p. 175

4a Eyes meeting on frons; fly is a male 4b Eyes separated; fly is a female 5a Male: abdomen extends to about wing-tips 5b Male: abdomen extends well beyond wing-tips

2 4

5  14 6  Common Globetail Sphaerophoria scripta p. 167

6a Male genitalia: hairy lobes about as long as wide or no longer than wide 7 6b Male genitalia: hairy lobes about 1.5 times longer than wide; toothed lobe very wide with narrow finger-like process at tip and a less distinct triangular process on inner side  Black-footed Globetail Sphaerophoria philanthus p. 169 7a Male genitalia: hairy lobes usually distinctly shorter than half the width at base when viewed from behind, therefore inner processes visible 7b Male genitalia: length of hairy lobes roughly equalling width at base, obscuring inner processes

8 9

8a Male: side margin of tergite 3 with yellow hairs. Genitalia: hairy lobes very low, without peaks; inner processes visible as parallel projections  Eastern Globetail Sphaerophoria chongjini p. 173 8b Male: side margin of tergite 3 mainly or entirely covered with black hairs. Genitalia: hairy lobes semicircular; inner processes divergent  Tormentil Globetail Sphaerophoria potentillae p. 173 9a Male: tergite 2 with a pair of yellow spots 9b Male: tergite 2 with yellow band 10a Male genitalia: toothed lobe with a large, long, finger-like process 10b Male genitalia: toothed lobe with two processes

 10  11  Interrupted Globetail Sphaerophoria interrupta p. 171  Bog Globetail Sphaerophoria fatarum p. 171

11a Male genitalia: toothed lobe narrow, with two processes 11b Male genitalia: toothed lobe wide with one narrow process

 12  13

12a Male: side margin of tergite 3 with yellow hairs. Genitalia: inner side of surstylus, between hairy and toothed lobes, with a projection, sometimes present only on one side  Broad-banded Globetail Sphaerophoria taeniata p. 167 12b Male: side margin of tergite 3 with black hairs. Genitalia: inner side of surstylus, between hairy and toothed lobes, without projection  Pinewood Globetail Sphaerophoria batava p. 169 13a Male genitalia: inner processes narrow and pointed; toothed lobe broad, with a distinct shoulder; inner side of toothed lobe at tip with swelling covered with spines  Heath Globetail Sphaerophoria virgata p. 171 13b Male genitalia: inner processes broad with blunt tip; toothed lobe with less prominent shoulder; inner side of toothed lobe at tip without swelling covered with spines  Bankowska’s Globetail Sphaerophoria bankowskae p. 173 Females of Sphaerophoria are very hard and sometimes impossible to identify. The key overleaf is preliminary and mainly based on material from Belgium and the Netherlands.

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14a Female: face yellow or with narrow dark medial stripe; tergites 3 and 4 with bands or spots, if tergites 3 and 4 with pairs of spots, these spots narrow, one-quarter or one-fifth length of tergite and/or reaching side margin with full width; shape of abdomen variable  15 14b Female: face with wide median black stripe from mouth edge to antennae, stripe at least as wide as third antennal segment; tergites 2–4 with yellow paired spots that may be narrowly connected and that do not or only narrowly reach side margin; spots on tergite 3 and 4 rectangular and wide, at least one-third length of tergite; abdomen wide, sternite 3 wider than long  Interrupted Globetail Sphaerophoria interrupta p. 171 15a Female: abdomen wide, sternite 3 wider than long; tergites 3 and 4 with wide bands occupying at least one-third of tergite length; black band along posterior margin of tergite 5 on either side of central stripe even; sternites 5 and 6 without longitudinal fold  16 15b Female: abdomen elongated, sternite 3 as long as wide, if abdomen wide, tergites 3 and 4 with paired spots; black band along posterior margin of tergite 5 with a distinct anterior extension on both sides of central stripe; sternites 5 and 6 with or without longitudinal fold  17 16a Female: side margins of tergite 3 covered largely or entirely with black hairs; this character is uncertain, making identification uncertain  Broad-banded Globetail Sphaerophoria taeniata p. 167 16b Female: side margins of tergite 3 covered largely in yellow hairs on anterior half; this character is uncertain, making identification uncertain  Eastern Globetail Sphaerophoria chongjini p. 173 17a Female: tergites 3 and 4 with clearly separated yellow paired spots 17b Female: tergites 3 and 4 with bands that may be narrowly interrupted in middle

 18  22

18a Female: anterior third of side margins of tergite 3 with pale hairs. Wing: 40–60% of cell bm covered with microtrichia  19 18b Female: side margins of tergite 3 largely or entirely covered with black hairs. Wing: 80–100% of cell bm covered with microtrichia  20 19a Female: hind tarsus not distinctly darkened; underside of hind femur along bare zone with one or more hairs converted into short spines. Wing: 40% of cell bm covered with microtrichia, microtrichia lacking in basal third of cell  Common Globetail Sphaerophoria scripta p. 167 19b Female: hind tarsus usually distinctly darkened; underside of hind femur without one or more hairs converted into short spines along bare zone. Wing: 50–60% of cell bm covered with microtrichia, microtrichia almost reach cell base  Black-footed Globetail Sphaerophoria philanthus (dark morph) p. 169 20a Female: abdomen wide, sternite 3 wider than long; sternites 5 and 6 without longitudinal fold  21 20b Female: abdomen elongated, sternite 3 as long as wide or longer than wide; sternite 6 and often also sternite 5 with longitudinal fold  Bankowska’s Globetail Sphaerophoria bankowskae p. 173 21a Female: sternites 3 and 4 with 20–30 black hairs in posterior corners; sternites 5 and 6 equally long in middle  Tormentil Globetail Sphaerophoria potentillae p. 173 21b Female: sternites 3 and 4 with at most a few black hairs in posterior corners; middle of sternite 5 twice as long as sternite 6  Bog Globetail Sphaerophoria fatarum p. 171 22a Female: sternites 3 and 4 with at most a few black hairs; black band along posterior margin of tergite 5 with a distinct anterior extension on both sides of central stripe. Wing: 40–46% of cell bm covered with microtrichia 22b Female: sternites 3 and 4 covered mainly with black, easy-to-miss, hairs; black band along posterior margin of tergite 5 straight anteriorly on either side of central stripe. Wing: 50–90% of cell bm covered with microtrichia  Heath Globetail Sphaerophoria virgata 23a Female: at least anterior third of side margins of tergite 3 with pale hairs; bare zone on underside of hind femur usually not interrupted by hairs; tergites 3 and 4 with paired spots or bands 23b Female: side margins of tergite 3 largely covered with black hairs; bare zone on underside of hind femur usually interrupted by some hairs  Pinewood Globetail Sphaerophoria batava

 23 p. 171  24 p. 169

24a Female: hind tarsus not distinctly darkened; underside of hind femur along bare zone with one or more hairs converted into short spines. Wing: 40% of cell bm covered with microtrichia, microtrichia lacking in basal third of cell; scutellum usually largely covered with yellow hairs; yellow markings on abdomen variable, but often wider than species in 24b  Common Globetail Sphaerophoria scripta p. 167 24b Female: hind tarsus usually distinctly darkened; underside of hind femur without one or more hairs converted into short spines along bare zone. Wing: 50–60% of cell bm covered with microtrichia, microtrichia almost reach base of cell; scutellum usually largely covered with black hairs; yellow markings on abdomen usually narrow, occupying one-quarter tergite length  Black-footed Globetail Sphaerophoria philanthus p. 169 7 8 ⁞ HOVERF LI ES O F BRI TAIN AND NORTH-WE ST E U ROP E

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Key 4B 1a Underside, at least, of third antennal segment orange; tergites 3 and 4 with either bands or pairs of spots 1b Third antennal segment entirely black; tergites 3 and 4 with pairs of spots 2a Face partly or entirely yellow 2b Face black, at most with some yellow near eye 3a Tergites 3 and 4 without small yellow spots at anterior corners 3b Tergites 3 and 4 with small yellow spots at anterior corners

2 7

3  Needle Roundtail Meligramma cingulata p. 117 4  Gold-spotted Smoothtail Epistrophella euchroma p. 155

4a Tergite 2 with blunt spots or oblique crescent bars; scutellum with black hairs 4b Tergite 2 with sharply triangular spots; scutellum with yellow hairs

5  Ringed Beech Fly Fagisyrphus cinctus p. 127

5a Tergites 3 and 4 with bands or pairs of spots; if with pairs of spots, inner side of spots blunt and usually not reaching side margins. Female: frons with distinct large dust spots 6 5b Tergites 3 and 4 with pairs of triangular spots, at least those on tergite 3 reaching side margin. Female: frons with small, less distinct dust spots  Triangle-spotted Roundtail Meligramma triangulifera p. 117 6a Frons directly above lunule black, lunule itself yellow; tergites 3 and 4 usually with spots, sometimes with bands  Spotted Thintail Meliscaeva auricollis p. 115 6b Lunule and frons directly above lunule black; tergites 3 and 4 with bands  Banded Thintail Meliscaeva cinctella p. 115 7a Face partly black, at least with black median stripe; scutum without pair of yellow spots just before scutellum 8 7b Face entirely yellow; scutum usually with pair of yellow spots just before scutellum  Spotted Roundtail Meligramma guttata p. 117 8a Eyes meet on frons; fly is a male 8b Eyes separated; fly is a female

9  17

9a Male: face black; tergite 2 black, sometimes with small pair of spots 9b Male: face yellow with black median stripe; tergite 2 with a pair of spots

 10  12

10a Male: eyes with hairs 10b Male: eyes bare

 11  April Halfband Melangyna barbifrons p. 119

11a Male: side margin of tergite 2 largely covered with black hairs; tergite 2 black  Black Halfband Melangyna quadrimaculata 11b Male: side margin of tergite 2 covered mainly with white hairs; tergite 2 black or with small pair of spots  Sakhalin Halfband Melangyna pavlovskyi 12a Male: sides of scutellum with small black spot at anterior corner 12b Male: sides of scutellum with large wedge-shaped spot at anterior corner

p. 119 p. 125  13  15

13a Male wing: cell bm partly bare; scutum lightly dusted or shiny  14 13b Male wing: cell bm entirely covered with microtrichia; scutum densely dusted  Matt-backed Halfband Melangyna compositarum p. 123 14a Male: all hairs on scutum pale; at least half of cell bm bare; posterior half of sternite 2 largely undusted  Shiny-backed Halfband Melangyna umbellatarum p. 121 14b Male: posterior part of scutum partly covered with black hairs; no more than 40% of cell bm bare; sternite 2 dull  Pinewood Halfband Melangyna ericarum p. 123 15a Male: scutum mainly covered with pale hairs 15b Male: at least posterior half of scutum covered with black hairs

 16  Alder Halfband Melangyna arctica p. 123

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16a Male: spots on tergites 3 and 4 rectangular with rounded corners; face narrow; eyes meet at a right angle; hind femur mainly black  Spring Halfband Melangyna lasiophthalma p. 121 16b Male: spots on tergites 3 and 4 tapering inwards; face wide; eyes meet at an angle of c. 120°; basal half of hind femur pale  Silver Halfband Melangyna lucifera p. 125 17a Female: tergites 2–4 with distinct paired pale spots; face partly pale  18 17b Female: abdomen black, seldomly with very small rudimentary spots on tergites 3 and 4; face black  Black Halfband Melangyna quadrimaculata p. 119 18a Female: frons with distinct grey dusting 18b Female: frons undusted, shining, or with rudimentary dust spots

 19  April Halfband Melangyna barbifrons p. 119

19a Female: sides of scutellum with small black spot at anterior corner 19b Female: sides of scutellum with large wedge-shaped spots

 20  22

20a Female: scutum shiny. Wing: cell bm partly bare  21 20b Female: scutum dull. Wing: cell bm entirely covered with microtrichia  Matt-backed Halfband Melangyna compositarum p. 123 21a Female: spots on tergite 2 reaching anterior corners; sternite 2 shiny  Shiny-backed Halfband Melangyna umbellatarum p. 121 21b Female: spots on tergite 2 not reaching anterior corners; sternite 2 dusted  Pinewood Halfband Melangyna ericarum p. 123 22a Female: eyes with hairs; frons with narrow dust band which is often interrupted in middle  23 22b Female: eyes bare; frons in front of vertex largely dusted  Alder Halfband Melangyna arctica p. 123 23a Female: spots on tergite 4 rectangular with rounded corners, without distinct dusting; mid tibia usually with dark ring  24 23b Female: spots on tergite 4 tapering towards centre, with silvery dusting (best seen from the side); mid tibia yellow  Silver Halfband Melangyna lucifera p. 125 24a Female: anterior part mouth edge black, posterior part yellow; sternites with yellow spots; hairs on eyes short; mid tibia with dark ring or dark markings on outer part; yellow spots on tergite 2 large and rectangular. Wing: basal part of cell bm bare  Spring Halfband Melangyna lasiophthalma p. 121 24b Female: mouth edge black; sternites black; hairs on eyes long; at least apical half of mid tibia dark; yellow spots on tergite 2 small and short. Wing: cell bm entirely covered with microtrichia  Sakhalin Halfband Melangyna pavlovskyi p. 125

Key 4C Aphideaters Eupeodes 1a Eyes meet on frons; fly is a male 1b Eyes separated; fly is a female

2 9

2a Male genitalia: not conspicuously large, not reaching the posterior margin of sternite 4 3 2b Male genitalia: conspicuously large, reaching posterior margin of sternite 4, making centre of sternite 5 constricted to anterior margin  Migrant Aphideater Eupeodes corollae p. 161 3a Male: scutellum covered mainly or entirely with black hairs; bands or pairs of spots on tergites 3 and 4 with undulating anterior margin 4 3b Male: scutellum covered mainly or entirely with yellow hairs; anterior margin of bands or pairs of spots on tergites 3 and 4 almost straight  Broad-banded Aphideater Eupeodes latifasciatus p. 161 4a Male: over half of wing covered with microtrichia; eyes meet at angle of 105° or less 5 4b Male: about basal half of wing bare, without microtrichia; eyes meet at obtuse angle of c. 120°  Smooth-winged Aphideater Eupeodes lundbecki p. 161 5a Male: at least half of side margin of tergite 5 black; occiput near vertex narrow, less than one-third of maximum width, in side-view occiput near vertex disappears behind eyes; posterior part of fore femur largely covered with black hairs 5b Male: side margin of tergite 5 yellow, at most anterior corner black; occiput near vertex less narrow, in side-view occiput near vertex remains visible as narrow strip; posterior part of fore femur at least partly covered with yellow hairs

6 7

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6a Male: tergites 3 and 4 almost always with narrow undulating band; eyes meet at an acute angle. Wing: over half of cell bm covered with microtrichia; alula entirely covered with microtrichia  Wavy-banded Aphideater Eupeodes nitens p. 161 6b Male: paired spots on tergites 3 and 4 fairly small and usually not fused; eyes meet at obtuse angle. Wing: less than half of cell bm covered with microtrichia; alula bare at base  Pinewood Aphideater Eupeodes nielseni p. 163 7a Male: alula entirely covered with microtrichia; tergites 3 and 4 usually with a narrow undulating band 8 7b Male: alula with bare area at base; tergites 3 and 4 usually with wide spots that are not connected  Lunuled Aphideater Eupeodes luniger p. 163 8a Male: black spot on at least tergite 3 rectangular, usually with pointed anterior corners; markings on tergites 3 and 4 usually narrower, band less constricted in middle. Wing: about half of cell bm covered with microtrichia  Narrow-banded Aphideater Eupeodes bucculatus p. 165 8b Male: black spots on sternites smaller, more rounded; markings on tergites 3 and 4 usually wider, band more constricted in centre. Wing: over half of cell bm covered with microtrichia  Goeldlin’s Aphideater Eupeodes goeldlini p. 165 9a Female: frons with border between black upper part and yellow lower part straight; scutellum largely covered with yellow hairs  10 9b Female: frons with black Y- or V-shaped marking extending into yellow; scutellum largely covered with black hairs  11 10a Female: tergites 3 and 4 with pairs of spots with undulating anterior margin; frons with dust spots  Migrant Aphideater Eupeodes corollae p. 161 10b Female: tergites 3 and 4 with bands with straight anterior margin; frons shining, without dust spots  Broad-banded Aphideater Eupeodes latifasciatus p. 161 11a Female: alula with bare area at base 11b Female: alula entirely covered with microtrichia

 12  15

12a Female: frons in side view slightly concave. Wing: at least two-thirds covered with microtrichia, at least outer part of cell bm covered with microtrichia  13 12b Female: frons in side view convex. Wing: about basal half of wing bare, without microtrichia; cell bm entirely or almost bare  Smooth-winged Aphideater Eupeodes lundbecki p. 159 13a Female: posterior part of fore femur with yellow hairs; side margin of tergite 5 yellow, rarely partly black in early spring specimens; dark markings on sternites oval or rectangular with rounded corners, rarely in dark specimens rectangular and very large  14 13b Female: posterior part of fore femur with black hairs; side margin of tergite 5 mainly black; dark markings on sternites rectangular and very large  Pinewood Aphideater Eupeodes nielseni p. 163 14a Female: face at widest point c. 1.1–1.5 times wider than an eye at widest point; dark spot on sternite 3 usually rounded oval, 2–3 times wider than high; tergites 3 and 4 almost always with paired spots  Lunuled Aphideater Eupeodes luniger p. 163 14b Female: face at widest point c. 0.8–1.1 times wider than an eye at widest point; dark spot on sternite 3 usually large and rectangular, 3–4 times wider than high; tergites 3 and 4 almost always with bands  Narrow-banded Aphideater Eupeodes bucculatus p. 165 15a Female: femora with black base; posterior part of fore femur with yellow hairs; black bands or spots on sternites 3 and 4 do not reach side margin; sternite 5 usually with black spot or spots, seldom with black band  16 15b Female: femora yellow or only very base black; posterior part of fore femur largely covered with black hairs; black bands on sternites 3 and 4 reach side margin, often with pointed anterior corners; sternite 5 with black band  Wavy-banded Aphideater Eupeodes nitens p. 161 16a Female: sternites 3 and 4 with large black bands, rectangular with slightly rounded corners; sternite 5 yellow or with black central spot, sometimes also with small black side spots. Wing: alula usually with bare area at base  Narrow-banded Aphideater Eupeodes bucculatus p. 165 16b Female: sternites 3 and 4 with wide oval black spots, never rectangular; sternite 5 yellow, usually with black side spots, sometimes with black central spot. Wing: alula always entirely covered with microtrichia  Goeldlin’s Aphideater Eupeodes goeldlini p. 165

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Key 5 1a Wing: cell r1 open 1b Wing: cell r1 closed

2  28

2a Underside of hind femur tip with a triangular process 2b Underside of hind femur tip without triangular process

3  12

3a Abdomen at most with a pair of orange spots on tergite 2, tergite 3 without large orange spots. Wing: vein M1 meets vein R4+5 well before wing-tip; vein M1 perpendicular to vein R4+5 4 3b Abdomen with large orange pairs of spots on tergites 2 and 3. Wing: vein M1 meets vein R4+5 at an acute angle, only just before wing-tip  Hairy Thickleg Tropidia fasciata p. 397 (see also Key 6, 38b) 4a Smaller species that usually does not mimic bumblebees; if mimicking a bumblebee, smaller than 10 mm; legs bicoloured, at least knee of fore leg yellow 5 4b Large species, 12–14 mm; mimics a bumblebee and has different colour morphs; legs black  Narcissus Bulb Fly Merodon equestris p. 369 5a Eyes meet; fly is a male 5b Eyes widely separated; fly is a female

6 9

6a Male: hind trochanter without spiny process 6b Male: hind trochanter with spiny process

7 8

7a Male: tergites 3 and 4 with oblique grey dust stripes 7b Male: tergites 3 and 4 without markings

 Tapered Bulb Fly Merodon moenium p. 367  Uniform Bulb Fly Merodon rufus p. 367

8a Male: pointed process on underside of hind femur in middle and on underside of hind tibia near tip; body with sparse yellow hairs; larger species  Spine-legged Bulb Fly Merodon ruficornis p. 367 8b Male: pointed processes on hind leg as described in 8a absent; body with dense golden-yellow hairs; small species  Golden Bulb Fly Merodon aureus p. 369 9a Female: scutum without longitudinal dust stripes 9b Female: scutum with four distinct longitudinal dust stripes 10a Female: tergite 2 with orange–yellow spots 10b Female: tergite 2 with a pair of grey-dusted stripes 11a Female: tergites 3 and 4 black 11b Female: tergites 3 and 4 with pairs of grey-dusted stripes

 10  Tapered Bulb Fly Merodon moenium p. 367  11  Golden Bulb Fly Merodon aureus p. 369  Uniform Bulb Fly Merodon rufus p. 367  Spine-legged Bulb Fly Merodon ruficornis p. 367

12a Scutum without grey dust pattern  13 12b Scutum with grey–yellow dusting, pattern of dusted and undusted parts resembling a skull or the Batman(!) logo  Common Batman Fly Myathropa florea p. 343 13a Species that mimics bumblebees or honey bees; scutum without pale longitudinal stripes 13b Species that does not mimic bumblebees or honey bees; scutum with pale longitudinal stripes 14a A bumblebee-mimicking species; eyes with hairs 14b A honey bee-mimicking species; eyes bare

 14  15

 Bumble Mimic Mallota fuciformis p. 343  Northern Bee Mimic Mallota cimbiciformis p. 343

15a Third antennal segment black; face with bare yellow or black median stripe 15b Third antennal segment orange; face with hairs in middle, with median stripe that may be very narrow

 16  21

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16a Tergites 2–4 not with yellow to greyish-longitudinal stripes 16b Tergites 2–4 with yellow to greyish-longitudinal stripes

 17  Clubrush Fly Lejops vittatus p. 347

17a Face with wide bare black median stripe  18 17b Female: face with bare yellow or orange median stripe, median stripe at most a little darkened around facial tubercle  Lemon Marsh Fly Helophilus trivittatus p. 351 18a At most basal third of hind tibia orange 18b Basal two-thirds of hind tibia orange 19a Posterior margin of all tergites black 19b Posterior margin of tergites 3–5 narrowly orange

 19  Tiger Marsh Fly Helophilus pendulus p. 351  20  Woolly-tailed Marsh Fly Helophilus hybridus p. 351

20a Scutum covered entirely with yellow hairs; fore tarsus partly pale; markings on tergite 2 with blunt inner side  Migrant Marsh Fly Helophilus affinis p. 353 20b Posterior part of scutum largely covered with black hairs; fore tarsus black; markings on tergite 2 with pointed inner side  Black-margined Marsh Fly Helophilus groenlandicus p. 353 21a Face somewhat protruding, or if strongly protruding, not to a point 21b Face strongly protruding to a point

 22  Snouted Duck Fly Eurimyia lineata p. 345

22a At least basal two-thirds of hind tibia yellow; abdomen wider than thorax  23 22b Hind tibia yellow with black rings at base and tip, which may be faint; abdomen narrow, as wide as or narrower than thorax  25 23a Tip of fore tibia yellow or with black spot which is not continuous on all sides; face only slightly protruding; brown–black longitudinal stripes on scutum; scutellum dull  24 23b Tip of fore tibia with black spot, continuous on all sides; face more distinctly protruding; black longitudinal stripes on scutum; scutellum shiny  Black-ankled Stripeback Parhelophilus consimilis p. 349 24a Hairs on upper part of occiput yellow. Male: underside of hind femur base without projection  Marsh Stripeback Parhelophilus versicolor p. 349 24b Upper part of occiput with a row of black hairs among yellow hairs. Male: projection on underside of hind femur base, with tuft of black bristles  Tuberculate Stripeback Parhelophilus frutetorum p. 349 25a Markings on tergites 2 and 3 hook shaped, pointed forwards. Male: underside of hind femur base with distinct bulge 25b Markings on tergites 2 and 3 not hook shaped but pointed towards centre. Male: underside of hind femur base without distinct bulge

 26  27

26a Side margin of tergite 2 straight. Male: sternites 2 and 3 entirely dull. Female: tergite 2 with distance between anterior edge of pale markings to anterior margin of tergite shorter than distance between pale markings  Golf-club Swamp Fly Anasimyia transfuga p. 347 26b Tergite 2 slightly waisted, especially in female. Male: sternites 2 and 3 dull with shiny longitudinal stripe in the middle. Female: tergite 2 with distance between anterior edge of pale markings to anterior margin of tergite larger than distance between pale markings  Waisted Swamp Fly Anasimyia contracta p. 347 27a Face only slightly protruding. Male: anterior margin of tergite 4 black and undusted for most of its width. Female: hairs on tergite 5 yellow  Ditch Swamp Fly Anasimyia interpuncta p. 345 27b Face distinctly protruding. Male: anterior margin of tergite 4 heavily dusted yellowish grey for almost entire width, only narrowly black and undusted in middle. Female: tergite 5 with some black hairs intermixed in the yellow ones  Bogbean Swamp Fly Anasimyia lunulata p. 345

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28a Eyes with dark spots on light background 28b Eyes without dark spots on light background

 29  30  Black Lagoon Fly Eristalinus sepulchralis p. 341  Common Lagoon Fly Eristalinus aeneus p. 341

29a Eyes densely covered with hairs. Male: eyes widely separated 29b Only upper third of eyes with hairs. Male: eyes meet 30a Body covered in long dense hairs; bumblebee mimics 30b Body not covered in long dense hairs; honey bee mimics 31a Sides of thorax with black hairs 31b Body covered entirely with white–yellow hairs

 31  33  32  Orange-spotted Drone Fly Eristalis anthophorina p. 339

32a Scutellum orange–yellow; scutellum with orange–brown hairs; hind tarsus black; calypter grey–black; arista with long hairs  Furry Drone Fly Eristalis intricaria p. 339 32b Scutellum whitish; scutellum with white hairs; hind tarsus largely yellow; calypter white; arista with short hairs  Orange-tailed Drone Fly Eristalis oestracea p. 339 33a Fore tarsus partly or entirely black 33b Fore tarsus entirely yellow 34a Eyes without vertical stripes of dark hairs 34b Eyes with two vertical stripes of dark hairs but not obvious from every angle

 34  Tapered Drone Fly Eristalis pertinax p. 329  35  Common Drone Fly Eristalis tenax p. 329

35a Wing: pterostigma dark brown, not conspicuously long; small to medium-sized species  36 35b Wing: pterostigma brown, conspicuously long; larger species, 13–16 mm  Glass-winged Drone Fly Eristalis similis p. 329 36a Face hairs all white, so no black median face stripe 36b Face with white hairs except in middle, producing bare black median stripe

 37  38

37a Arista with long hairs; apical quarter or third of mid tibia black. Male: eyes meet along a considerable length  Eurasian Drone Fly Eristalis arbustorum p. 331 37b Arista with short hairs; mid tibia entirely yellow, at most tip with brown smudge. Male: eyes close but do not meet  Levels Drone Fly Eristalis abusiva p. 331 38a Wing: pterostigma distinctly longer than wide. If in doubt, posterior side of fore femur with black hairs; wing usually with central dark spot  39 38b Wing: pterostigma short, not much longer than wide. Posterior side of fore femur with yellow hairs. Male: wing transparent. Female: wing transparent or veins darkened brown, but not with central dark spot  Stripe-faced Drone Fly Eristalis nemorum p. 331 39a Arista with short hairs 39b Arista with long hairs

 40  41

40a Legs largely black, only knees and base of tibiae yellow  Orange-spotted Drone Fly Eristalis anthophorina p. 339 40b Legs largely orange, only base of femora and outer tarsomeres of tarsi black  Bog-dwelling Drone Fly Eristalis cryptarum p. 341

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41a Face not or only slightly protruding downwards; yellow or black hairs on posterior side of fore femur not dense; hind femur yellow or black at base  42 41b Face clearly protruding downwards; posterior side of fore femur with dense hairs, black in male, yellow in female; hind femur black at base  Snouted Drone Fly Eristalis jugorum p. 333 42a Scutum colour uniform, shiny or slightly dusted. Male: hind femur not swollen and curved. Female: usually base of hind femur black or at most one-quarter yellow  43 42b Scutum densely dusted, anterior part thicker than posterior part, creating contrast between greyish anterior part and blackish posterior part. Male: hind femur swollen and curved, with concave underside. Female: usually basal half of hind femur yellow  Dusted Drone Fly Eristalis alpina p. 337 43a Eyes meet on frons; fly is a male 43b Eyes separated; fly is a female

 44  47

44a Male: face black below white dusting; posterior side of fore femur largely covered with black hairs; at least yellow spots on tergite 2 shiny  45 44b Male: face yellow below white dusting; posterior side of fore femur largely covered with yellow hairs; tergite 2 entirely dusted  Stripe-winged Drone Fly Eristalis horticola p. 333 45a Male: pterostigma about 1.5–2 times longer than wide; sternites 2 and 3 dull, contrasting with less densely dusted sternite 4. Genitalia: lobes on aedeagus strongly curved  46 45b Male: pterostigma about 3–3.5 times longer than wide; sternites 2–4 shiny. Genitalia: lobes on aedeagus weakly curved  Spot-winged Drone Fly Eristalis rupium p. 337 46a Male: wing with central dark spot. Genitalia: tip of paramere pointed 46b Male: wing transparent. Genitalia: tip of paramere broad

 Spring Drone Fly Eristalis picea p. 335  Carr Drone Fly Eristalis pseudorupium p. 335

47a Female: posterior half of tergite 3 with black hairs; at least yellow spots on tergite 2 shiny  48 47b Female: tergite 3 with yellow hairs; tergite 2 entirely dusted  Stripe-winged Drone Fly Eristalis horticola p. 333 48a Female: tergites 3 and 4 with dull posterior and usually also anterior margin. Wing: pterostigma about 1.5–2 times longer than wide  49 48b Female: tergites 3 and 4 shiny. Wing: pterostigma about 3–3.5 times longer than wide  Spot-winged Drone Fly Eristalis rupium p. 337 49a Female: tergite 3 with fairly long erect hairs; tergite 2 with yellow spots and black band between them shiny; scutellum with yellow hairs, or with only few black hairs intermixed; scutum dull  Spring Drone Fly Eristalis picea p. 335 49b Female: posterior half of tergite 3 with fairly short semi-erect hairs; tergite 2 shiny, with yellow spots but black band between them dull; scutellum with band of black hairs; scutum shiny  Carr Drone Fly Eristalis pseudorupium p. 335

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♂

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Key 6 1a Arista with very long hairs 1b Arista bare

2 5

2a Body with long dense hairs, a bumblebee mimic 2b Body with short hairs, not a bumblebee mimic; abdomen usually with whitish or yellow bands

3 4

3a Hairs on body black, yellow and white 3b Hairs on body orange, yellow and white

 Bumblebee Pond Fly Sericomyia bombiformis p. 355  Furry Pond Fly Sericomyia superbiens p. 355

4a Abdomen with wide yellow bands that reach side margin; tergite 5 largely yellow. Male: tergite 8 yellow  Yellow-barred Pond Fly Sericomyia silentis p. 353 4b Abdomen with narrow white–yellow bands that do not reach side margin, abdomen seldom all black; tergite 5 black. Male: tergite 8 black  White-barred Pond Fly Sericomyia lappona p. 355 5a Fly is a bumblebee or a bee mimic 5b Fly does not mimic a bumblebee or a bee

6  14

6a Face without facial tubercle and not protruding downwards 6b Face with (sometimes indistinct) facial tubercle; face protruding downwards

7  10

7a Fly is a honey bee mimic. Wing: vein M1 meets vein R4+5 well before wing-tip 7b Fly is a bumblebee mimic. Wing: vein M1 meets vein R4+5 near wing-tip

8  Eurasian Pocota Pocota personata p. 385

8a Scutum without grey dusted longitudinal stripes; tergite 2 without large pair of grey dust spots; metasternum bare 9 8b Scutum with grey dusted longitudinal stripes; tergite 2 with large pair of grey dust spots; metasternum with long hairs  Logjammer Chalcosyrphus eunotus p. 387 9a Transverse suture and notopleuron dusted; arista dark brown. Male: eyes meet along a considerable length; underside of hind tibia without projection. Female: frons mostly dusted  Thick-thighed Forest Fly Brachypalpus laphriformis p. 385 9b Transverse suture and notopleuron shiny; arista yellow. Male: eyes close, almost meet; underside of hind tibia with projection. Female: frons shiny  Greater Forest Fly Brachypalpus valgus p. 385 10a Fly is a honey bee mimic; abdomen without long dense hairs 10b Fly is a bumblebee mimic; abdomen with long dense hairs

 11  12

11a Fore tarsus with outer tarsomeres black; tergite 2 with distinct pair of dusted stripes; hind femur hardly swollen  Bee Bumblefly Criorhina asilica p. 383 11b Fore tarsus orange; pair of dusted stripes on tergite 2 indistinct or absent; hind femur strongly swollen, especially in male  Poplar Bumblefly Criorhina pachymera p. 383 12a Hairs on scutum partly or entirely orange–yellow; fore and mid tibiae without row of long hairs on outer side  13 12b Hairs on scutum black, although rare morph with yellow hairs occurs; fore and mid tibiae with row of long hairs on outer side  Large Bumblefly Criorhina ranunculi p. 383 13a Anterior corners of tergite 2 with long pale or black hairs, but hairs not conspicuously longer than surrounding hairs; tibia with black hairs; third antennal segment orange–brown  Dimorphic Bumblefly Matsumyia berberina p. 381 13b Anterior corners of tergite 2 with tufts of long pale hairs, conspicuously longer than surrounding hairs; tibiae with yellow hairs; third antennal segment black  Buff-tailed Bumblefly Criorhina floccosa p. 381

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1b

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14a Fly is a convincing wasp mimic: scutum black with bright yellow markings, abdomen with yellow markings 14b Fly does not mimic a wasp; scutum ranging from black to green, without yellow markings

 15  22

15a Wing: cell r1 open; abdomen partly black  16 15b Wing: cell r1 closed. Abdomen with yellow and brown markings, no distinct black markings; a very large species, mimicking a hornet  Hornet Giant Milesia crabroniformis p. 375 16a Eyes with spots and stripes 16b Eyes uniform in colour

 17  18

17a Scutum with long hairs; fore tarsus black; fore tibia black, except for yellow base  Hairy Hornet Fly Spilomyia manicata p. 377 17b Scutum with short hairs; at least outer two tarsomeres of fore tarsus yellow; fore tibia yellow or only tip black  Fivespot Hornet Fly Spilomyia saltuum p. 377 18a Posterior corners of scutum black, without yellow dusted spots 18b Posterior corners of scutum with yellow dusted spots

 19  20

19a Anterior half of wing not strongly darkened; abdomen oval; tergites 2–4 with two greyish-yellow bands on each tergite  Bleached Falsehorn Temnostoma apiforme p. 379 19b Anterior half of wing strongly darkened; abdomen elongated; tergites 2–4 with one yellow band on each tergite  Dusky Falsehorn Temnostoma bombylans p. 381 20a Tergites 2–4 in male, 2–5 in female, with two distinct yellow bands per tergite  21 20b Tergites 2–4 in male, 2–5 in female, with only one distinct yellow band per tergite  Belted Falsehorn Temnostoma sericomyiaeforme p. 379 21a Spot on scutum just before scutellum roughly triangular; transverse suture with solid yellow stripe; posterior corners of scutum with wedge-shaped yellow spots that reach postalar calli  Wasp Falsehorn Temnostoma vespiforme p. 377 21b Spot on scutum just before scutellum semicircular; transverse suture with interrupted yellow stripe; posterior corners of scutum with wedge-shaped yellow spots that do not reach postalar calli  Moon Falsehorn Temnostoma meridionale p. 379 22a Not with combination of yellow face and oval, red-tipped abdomen 22b Tip of abdomen red; abdomen oval; face yellow

 23  Pine Hoverfly Blera fallax p. 375

23a Hind femur not swollen, without spines on underside; face yellow; abdomen with bright brassy and/or coppery shine 23b Hind femur usually swollen; underside of hind femur with spines; face not yellow; abdomen without bright coppery shine

 24  26

24a Sides of scutum with pale hairs and black bristles; crossveins r-m and bm-m darkened  25 24b Sides of scutum with golden-yellow hairs only; crossveins r-m and bm-m not darkened  Jewel Wood Fly Caliprobola speciosa p. 375 25a Arista black; haltere dark; fore and mid legs with scattered black bristles  Eurasian Copperback Ferdinandea cuprea p. 267 25b Arista orange, but may be black in male; haltere orange; fore and mid legs without or with only few black bristles  Orange-horned Copperback Ferdinandea ruficornis p. 267 26a Wing: vein M1 strongly bent in apical part. Scutum anteriorly with pair of white longitudinal stripes; face flat and receding; abdomen with pairs of white dust stripes on blackish or red background  27 26b Wing: vein M1 not strongly bent in apical part. Scutum without pair of white longitudinal stripes; face with clearly protruding mouth edge  37 27a Abdomen with red markings 27b Abdomen without red markings

 28  30

28a Eyes (almost) bare; basal three tarsomeres of fore and mid tarsi with yellow markings  29 28b Eyes with hairs; fore and mid tarsi brown-black  Goatsbeard Roundface Eumerus tricolor p. 365

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15a 14a

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29a Smaller species, 7–9 mm; tip corners of tarsomeres of fore leg without black bristles. Male: eyes close, almost meeting at one place. Female: ocelli in an isosceles triangle, distance from posterior ocelli to anterior ocellus shorter than distance between posterior ocelli  Sheep’s-bit Roundface Eumerus sabulonum p. 365 29b Larger species, 9–11 mm; tip corners of tarsomeres 1–4 of fore leg with black bristles. Male: eyes meet over considerable distance. Female: ocelli in an equilateral triangle  Peg-footed Roundface Eumerus tarsalis p. 365 30a Tergites 2–4 with pair of grey dusted spots, tergite 2 without pair of small oval spots  31 30b Tergites 3 and 4 with pair of grey dusted spots; tergite 2 with pair of small oval yellow spots  Silver-footed Roundface Eumerus flavitarsis p. 363 31a Distance between anterior and posterior ocelli similar or larger than distance from posterior ocelli to eye corners; hind femur strongly thickened. Male: eyes meet over a distance shorter than ocellar triangle  32 31b Distance between anterior and posterior ocelli less than distance from posterior ocelli to eye corners; hind femur moderately thickened. Male: eyes meet over a distance longer than ocellar triangle  Woodland Roundface Eumerus ornatus p. 363 32a Underside of hind femur at basal half without tubercle. Female: anterior part of sides of tergite 5 without ridge  33 32b Underside of hind femur bare and shiny, with tubercle at base although may be indistinct in female. Female: anterior part of side margin of tergite 5 with ridge  Lesser Roundface Eumerus funeralis p. 361 33a Male: posterior margin of tergite 4 black. Female: vertex with pale grey dust spots against eye margin, adjacent to ocelli  34 33b Male: posterior margin of tergite 4 yellow. Female: vertex without pale grey dust spots against eye margin  Viper’s-grass Roundface Eumerus ruficornis p. 361 34a Distance from posterior ocelli to posterior margin of head less than twice that to anterior ocellus. Male: surstylus prominent, not cone shaped. Female: tergite 5 covered with pale hairs  35 34b Distance from posterior ocelli to posterior margin of head more than twice that to anterior ocellus. Male: surstylus not prominent, cone shaped. Female: tergite 5 covered with black hairs  Daffodil Roundface Eumerus narcissi p. 361 35a Third antennal segment brown–black, at most underside dark orange  36 35b Third antennal segment bright orange at base  Orange-horned Roundface Eumerus amoenus p. 363 36a Male: sternite 4 with V-shaped posterior margin, with notch at the bottom of the V. Genitalia: surstylus with hook. Female: not possible to distinguish from females of next (36b) species  Onion Roundface Eumerus strigatus p. 359 36b Male: sternite 4 with drop-shaped notch on posterior margin. Genitalia: surstylus without hook. Female: not possible to distinguish from females of previous (36a) species  Slender Roundface Eumerus sogdianus p. 359 37a Wing: vein M1 meets vein R4+5 just before wing-tip; vein R4+5 with a dip into cell r4+5 37b Wing: vein M1 meets vein R4+5 well before wing-tip; vein R4+5 nearly straight

 38  39

38a Scutum black, shiny, with short golden-yellow hairs; wing: vein R4+5 with a shallow dip into cell r4+5  Swamp Thickleg Tropidia scita p. 397 38b Scutum bronze, dusted, with two dusted longitudinal stripes anteriorly; scutum with long golden-yellow hairs; wing: vein R4+5 with a deep dip into cell r4+5  Hairy Thickleg Tropidia fasciata p. 397 39a Sides of thorax without dense white dusting; if abdomen with spots, third antennal segment black 39b Sides of thorax with dense white dusting; abdomen with spots; third antennal segment orange  Common Compost Fly Syritta pipiens 40a Tergites 2 and 3 largely red 40b Tergites 2 and 3 at most with reddish spots, or coloured differently

 40 p. 397  41  45

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41a Legs black 41b Legs partly pale

 42  43  Crimson-belted Leafwalker Brachypalpoides lentus p. 389  Red-tailed Leafwalker Chalcosyrphus piger p. 389

42a Tip of abdomen black 42b Tip of abdomen red 43a Tip of hind tibia black; fore and mid tibiae with black ring 43b Tip of hind tibia yellow; fore and mid tibiae pale

 44  Red-belted Leafwalker Xylota ignava p. 395

44a Underside of hind tibia base with field of short black bristle-like hairs; underside of hind femur tip with double row of large spines, outer row reaching basal part of femur. Male: hind trochanter with long slender spur  Orange-belted Leafwalker Xylota segnis p. 395 44b Underside of hind tibia base without field of short black bristle-like hairs; underside of hind femur tip with numerous small black spines. Male: hind trochanter with short blunt spur  Aspen Leafwalker Xylota tarda p. 395 45a Abdomen with dense golden-yellow hairs at tip 45b Abdomen without dense golden-yellow hairs at tip

 46  47

46a Tip of tibiae dark, although not obvious from every angle 46b Hind tibia entirely yellow 47a Abdomen black; femora red 47b Abdomen with spots; femora black 48a Haltere grey or black; pterostigma yellow–brown 48b Haltere yellow–brown; pterostigma dark brown

 Golden-tailed Leafwalker Xylota sylvarum p. 393  Yellow-shinned Leafwalker Xylota xanthocnema p. 393  48  49

 Lesser Orange-thighed Leafwalker Chalcosyrphus valgus p. 387  Greater Orange-thighed Leafwalker Chalcosyrphus femoratus p. 387

49a At least basal fifth, but usually basal third, of hind tibia yellow; when in doubt, tergite 2 squarish; metasternum bare  50 49b Only very base of hind tibia yellow; tergites 2 and 3 distinctly wider than long; metasternum with hairs  Small Leafwalker Chalcosyrphus nemorum p. 389 50a Basal two tarsomeres of fore tarsus yellow 50b Basal three tarsomeres of fore tarsus yellow

 51  52

51a Approximately basal fifth of hind tibia yellow. Male: tergite 8 with pale hairs. Female: dusted band on frons with straight posterior margin  Alder Leafwalker Xylota abiens p. 391 51b Approximately basal third of hind tibia yellow. Male: tergite 8 with black hairs. Female: posterior margin of dusted band on frons with deep notch  Spruce-stump Leafwalker Xylota jakutorum p. 391 52a Basal two-thirds of upper part of hind femur with white hairs of equal length, hairs not longer than one-quarter the width of hind femur; anterior and posterior anepisternum shiny. Male: tergite 8 with pale hairs  Smoky-winged Leafwalker Xylota meigeniana p. 391 52b Basal 80% of upper part of hind femur with white hairs, some hairs longer, equalling half the width of hind femur; anterior anepisternum dull, posterior anepisternum shiny. Male: tergite 8 with black hairs  Slim-tailed Leafwalker Xylota florum p. 393

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Species accounts

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p u p a ri u m

re ti cul a r pa tte rn co a rse

♂

sc u tu m

scutellum

bl a ck ha i rs

hind ma rgi n conca ve

re d-bro w n, 3 × l o nge r tha n w i de

p u p a ri u m

♂

sc u te l l u m

p o ste ri o r sp i ra c l e

hi gh a nd sl e nde r

hi nd ma rgi n stra i g ht

bl a ck -bro w n, 2 × l o nge r tha n w i de

p u p a ri u m

♂

p o ste ri o r sp i ra c l e

sho rt a nd w i de

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Chalk Ant Fly Microdon devius IDENTIFICATION 9–12 mm. Only Microdon in Western Europe that can also be identified when in adult stage. Face flat with long white hairs; antennae longer than head, first antennal segment as long as second and third antennal segments combined. Scutellum blackish, same colour as scutum; posterior margin of scutellum concave between teeth (look carefully through the dense hairs); scutum with an often-interrupted band of black hairs between wing bases. Wing: vein R4+5 with an appendix into cell r4+5. Femora black, tibiae and tarsi predominantly orange. Male: eyes widely separated. SIMILAR SPECIES Only Microdon with patches of black hairs on scutum; also, concave posterior margin of scutellum differentiates it from M. analis and M. major; scutellum not being red–brown differentiates it from M. mutabilis and M. myrmicae. OCCURRENCE Has seriously declined in North-west Europe. Only a handful of scattered populations remain in the east of the continental range covered in this book; considered Near Threatened in Great Britain. ECOLOGY Dry short-cropped

unimproved grasslands, often grazed chalk grassland. Flies low and inconspicuously through grass. Frequently sits on vegetation, usually in the vicinity of the nests of the larval host Lasius flavus. Probably does not visit flowers.

Heath Ant Fly Microdon analis IDENTIFICATION 8–11 mm. Very closely related to M. major; identification of adults not possible. Face flat with long white hairs; antennae longer than head. Scutum with pale hairs; scutellum blackish, same colour as scutum; posterior margin of scutellum between teeth almost straight; katepisternum with dense hairs in upper posterior part and some hairs halfway along anterior margin. Wing: up to half of cell br bare, basal part always with large bare area (no microtrichia). Male: eyes widely separated. Puparium: 7–9 mm. Dorsal surface of puparium ornamented with reticular pattern of ridges; anterior spiracle almost three times longer than its maximum basal diameter, pale brown to red–brown and with a fine reticulate pattern; posterior spiracle high and slender, almost conical. SIMILAR SPECIES Shares with M. major combination of scutum with pale hairs and blackish scutellum with straight posterior margin. Although on average smaller, distinguishing adult from M. major impossible, only larvae and puparia can be identified: larva and puparium usually smaller, and puparium paler and with longer anterior and posterior spiracles.

OCCURRENCE Confused with M. major but confirmed from the eastern and southern limits of the range covered in this book, and from Great Britain. ECOLOGY Forest glades and edges of open heathy woodland, felled areas with tree stumps. Occasionally in other open woodland types, preferentially on base-poor soil. Flies close to the ground with a slow and erratic flight. Males usually wait for emerging females near nests of the larval host. Larval hosts are ants of the genus Lasius, usually L. platythorax. Puparia are found in ant nests under bark of tree trunks.

Large Ant Fly Microdon major IDENTIFICATION 9–13 mm. A lookalike of M. analis, identification of adults not possible. Face flat with long white hairs; antennae longer than head, first antennal segment as long as second and third antennal segments combined. Scutellum with same darkbronze colour as scutum; scutum with pale hairs; posterior margin of scutellum between teeth almost straight; katepisternum with dense hairs in upper posterior part and some hairs halfway along anterior margin. Wing: vein R4+5 with an appendix into cell r4+5; up to half of cell br bare, at least with large bare area at base. Femora black, tibiae and tarsi orange. Male: eyes widely separated. Puparium: 9–11 mm. Surface of puparium covered entirely with reticular pattern of ridges; anterior spiracle at most twice as long as maximum basal diameter, black–brown and surface with coarse pattern; posterior spiracle short and wide. SIMILAR SPECIES Differs from M. devius by having pale hairs on scutum and straight posterior margin of scutellum. Differs from M. mutabilis and M. myrmicae by its darker scutellum; however, sometimes scutellum can appear quite dark in latter two, difference in

microtrichia on cell br and pattern of hairs on katepisternum diagnostic. Although on average larger, distinguishing adult from adults of M. analis impossible; for identification of puparium and larva, see M. analis. OCCURRENCE Scattered populations are known in the east of Belgium and the Netherlands; occurrence in other countries still unclear. Not known from Great Britain but reports of larvae of M. analis found in nests of Formica ants likely refer to this species. ECOLOGY Habitat and behaviour probably much like that of M. analis but insufficiently known owing to impossibility of identifying adults. Adults can be found near nests of the host F. sanguinea. Possibly also with other Formica ants such as F. fusca.

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sc u te l l u m

♂

re d-bro w n

p u p a ri u m

l o ng

po o rly de f i ne d pa tte rn

♀

a b d o me n

♂

sho rt

wel l -defi ne d p u p a ri u m

♀

♂

a b d o me n

ye l l o w stri pe s stro ngl y curv e d

ante rior e dge darke ne d

sho rt-ha i re d

♂

a b d o me n l a te ra l

ant enna

3 r d s e gme nt longer th a n 1 s t a nd 2 nd com bi ned .

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Bog Ant Fly Microdon myrmicae IDENTIFICATION 9–12 mm. Very similar to M. mutabilis. Antennae

longer than head. Scutellum red–brown, contrasting with darker scutum; posterior margin of scutellum slightly concave; katepisternum with dense hairs in upper posterior corner, remainder bare. Wing: vein R4+5 with an appendix into cell r4+5; cell br entirely or almost covered entirely with microtrichia, at most with small bare spot at base. Femora black, tibiae and tarsi orange. Male: eyes widely separated. Puparium: reticular pattern of ridges poorly defined and confined to sides, upper surface smooth, bald; anterior spiracle longer than width at base. SIMILAR SPECIES Reddish scutellum is shared only with M. mutabilis, but sometimes scutellum quite dark, causing confusion with other Microdon; pale hairs on scutum distinguish it from M. devius; differs from M. analis and M. major by bare anterior part of katepisternum and cell br covered entirely with microtrichia. Adults cannot be distinguished from those of M. mutabilis, but on average are smaller and habitat differs

(see below); larvae and puparia, however, can be distinguished. OCCURRENCE Vast majority of the continental records of Microdon with a red scutellum likely will be of M. myrmicae. Widespread but extremely local and fragmented in its range. ECOLOGY Habitat very different from that of M. mutabilis: wet heaths and unimproved poor wet grasslands, valley mires, often in ant nests in moss hummocks along mires. Flies low through vegetation and rests on blades of grass or on the ground. Not known to visit flowers. Larva lives in nests of ants of the genus Myrmica, often M. scabrinodis and M. rubra.

Limestone Ant Fly Microdon mutabilis IDENTIFICATION 9–14 mm. A lookalike of M. myrmicae;

identification of adult not possible. Antennae longer than head. Scutellum red–brown, contrasting with darker scutum; posterior margin of scutellum slightly concave; katepisternum with dense hairs in upper posterior corner, remainder bare. Wing: vein R4+5 with an appendix into cell r4+5; cell br entirely or almost covered entirely with microtrichia, at most with small bare spot at base. Femora black, tibiae and tarsi orange. Male: eyes widely separated. Puparium: reticular pattern of ridges well defined and confined to sides, upper surface smooth; anterior spiracle shorter than width at base. SIMILAR SPECIES Very similar to M. myrmicae; for differences with Microdon other than M. myrmicae see that species. Adults cannot be distinguished from those of M. myrmicae, although habitat differs and often larger, but sizes widely overlapping. Only larvae and puparia can be identified: both on average larger than in M. myrmicae and puparium with side reticulations better defined, darker colour and anterior spiracle shorter instead of longer than width at base. OCCURRENCE The very few North-west European populations are small and isolated and extremely

vulnerable. ECOLOGY From limestone pavements in Great Britain, on well-drained short-cropped chalk grasslands in nearby mainland Europe. Males fly low, back and forth, and sit regularly, often on favourite spots, presumably near nests of the host. Not known to visit flowers. Larva lives in underground ant nests of the genus Formica; on the British Isles known from nests of F. lemani; in Belgium and France known from F. cunicularia.

Naked Meadow Fly Chrysotoxum lessonae IDENTIFICATION 12–14 mm. A rather dark Chrysotoxum in

North-west Europe. Antennae longer than head; third antennal segment longer than first and second antennal segments combined. Scutellum with black spot in centre, otherwise yellow. Wing: dark along anterior edge, distinct in apical half. Tergites 3 and 4 with yellow posterior margin, usually in middle extending forward in shape of a triangle; pairs of yellow stripes on tergite 3 and 4 strongly curved, in posterior corners connected with yellow posterior margin, rendering posterior part of side margins yellow; abdomen with short hairs except anterior corners of tergite 2 with long hairs. SIMILAR SPECIES Dark specimens could be confused with C. festivum or C. vernale, but pairs of yellow stripes on tergites 3 and 4 usually reach side margin in the rare case when not, third antennal segment longer than first and second antennal segments combined. Distinguished from other Chrysotoxum treated in this book by its combination of third antennal segment longer than first and second antennal segments combined, pairs of sharply curved spots on tergites 3 and 4, dark anterior edge

of wing and short hairs on abdomen. OCCURRENCE Not known from Great Britain. Scattered records come from the eastern and southern limits of the range covered in this book, mostly as singletons. Has a long flight period with several generations between April and October. ECOLOGY Forest edge, forest glades along small river valleys. Visits low flowers. Larval biology unknown. COMMENT Until recently known as C. intermedium but the species in this complex found in Western Europe is C. lessonae.

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♀

a b d o me n

♂

♂

u n d e rsi d e a b d o me n

l o ngi tudi na l ke e l

l a rge ye l l o w spo ts

l o ng-ha i re d

ant enna

♂

3 r d s e gme nt about a s l o ng a s 1 s t a n d 2 nd co m bi ned

♂ ♂

ge ni ta l i a v e ry l a rge

a b d o me n l a te ra l

u n d e rsi d e a b d o me n

sm a l l spo ts

ge ni ta l i a sm a l l

l o ng-ha i re d

s mall s pe cie s

ant enna

♂

a b d o me n l a te ra l

a bdo m e n co nv e x

3 rd s e gme nt l o nger th a n 1 s t a nd 2 nd com bi ned

♀

a b d o me n

♂ a nte ri o r e dge da rke ne d

♂ ve ry large s pe cie s

u n d e rsi d e a b d o me n

antenn a

3 r d seg m ent l o nge r tha n 1 st a nd 2 n d co m bi ne d

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Large Meadow Fly Chrysotoxum cautum IDENTIFICATION 12–15 mm. A large Chrysotoxum. Antennae

longer than head; third antennal segment about as long as first and second antennal segments combined. Wing: not dark along anterior margin. Tergites 3 and 4 with yellow posterior margin, pairs of yellow lunules connected with yellow posterior margin, abdomen with fairly long yellow hairs; abdomen in side view not distinctly convex; sternites 2–4 with large yellow spots. Male: genitalia remarkably large. Female: hairs on scutum and scutellum long; tergite 6 with a medial longitudinal keel. SIMILAR SPECIES Male is unique among Chrysotoxum species in having very large genitalia, easy to assess even in the field with the naked eye. Female is unique among Chrysotoxum in having a medial longitudinal keel on tergite 6. Furthermore, is the only Chrysotoxum in the covered range with third antennal segment as long as the first and second antennal segments combined; in the other species, it is either longer or shorter, but this character is not always obvious given natural variation. OCCURRENCE A common

Chrysotoxum in North-west Europe, but restricted to the warmer areas (lower elevations, more southerly parts). ECOLOGY Speciesrich grasslands near woodland or scrubs. Frequently visits flowers of umbellifers and bushes; males fly fast along the forest edge and hill-tops. The species can also fly slowly through low herbage doing a splendid impersonation of a social wasp. Larval biology unknown, but females lay eggs in clumps of grasses, possibly associated with ant-tended root aphids.

Little Meadow Fly Chrysotoxum arcuatum IDENTIFICATION 9–12 mm. A small Chrysotoxum with short

convex abdomen. Antennae longer than head; third antennal segment longer than first and second antennal segments combined. Scutellum yellow with black centre. Wing: anterior margin not dark. Abdomen short and distinctly convex, with long hairs; tergites 3 and 4 with yellow posterior margin, pairs of yellow spots in posterior corners usually connected with yellow posterior margin, side margin of tergites partly yellow; sternite 2 black, except for yellow posterior margin; sternites 3 and 4 with small yellow spots. Male: genitalia not remarkably large. SIMILAR SPECIES The short convex abdomen is a helpful first identifying feature in the field. Like C. cautum, but male genitalia not that large and, in the female, tergite 6 without medial longitudinal cleft. Shares third antennal segment being longer than first and second antennal segments combined with only C. lessonae and C. fasciolatum. Differs from C. lessonae by having longer hairs on abdomen and wing-tip without dark anterior margin. Most resembles C. fasciolatum but is smaller, wing-tip without dark anterior margin and posterior margin of scutellum is

yellow. OCCURRENCE Both in Great Britain and mainland Europe the distribution alternates with that of C. cautum, C. arcuatum being the more northern and/or higher elevation species. ECOLOGY Moorland margins, unimproved grassy areas in forest on base-poor soil. Flies low through vegetation and visits low flowers. Egg-laying has been observed on grass above ant nests of the genus Lasius.

Greater Meadow Fly Chrysotoxum fasciolatum IDENTIFICATION 13–17 mm. A strikingly big Chrysotoxum.

Antennae longer than head; third antennal segment longer than first and second antennal segments combined. Anterior part scutellum yellow, remainder black. Wing: apical half along anterior margin distinctly dark. Tergites 3 and 4 with yellow posterior margin; pairs of yellow spots on posterior corner of tergites connected with yellow posterior margin; side margin of tergites partly yellow; sternite 2 black, except for yellow posterior margin; sternites 3 and 4 with small yellow spots, those on sternite 3 sometimes absent. Male: genitalia not remarkably large. SIMILAR SPECIES Like C. cautum, but markings on sternites different, male without very large genitalia and female without medial longitudinal keel on tergite 6. Shares third antennal segment being longer than first and second antennal segments combined with C. arcuatum and C. lessonae only. Identified from C. lessonae by its larger size, dark posterior margin of scutellum and longer hairs on abdomen. Most resembles C. arcuatum but is larger, less stocky and anterior margin of wing

apical half distinctly dark and scutellum with black posterior margin. OCCURRENCE Not known from Great Britain. Widely distributed over Europe, but in our range a very rare resident in north-western Germany and the east of Belgium; largely a mountain species south of Scandinavia. Flight period from May to August. ECOLOGY Forest glades and forest edges in mountains, on heathland in northern Germany. Larval biology unknown.

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♂

♂

a b d o me n

te rgi te 3 w i th na rro w ye l l o w ba nd

♀

a b d o me n

♂ stri pe s do no t re a ch si de m a rgi n

th o ra x l a te ra l fo re fem ur

k a te pi ste rnum w i th ye l l o w spo t bas e ye llow

♀

a b d o me n

♂ stri pe s do no t re a ch si de m a rgi n

th o ra x l a te ra l fo re fem ur

bas e black

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Two-banded Meadow Fly Chrysotoxum bicinctum IDENTIFICATION 8–12 mm. A small but very distinctive

Chrysotoxum. Antennae longer than head; third antennal segment shorter than first and second antennal segments combined. Wing: with distinctive black marking along centre of anterior edge. Tergites 2 and 4 with a wide yellow band; tergite 3 sometimes all black, but often with a pair of narrow yellow spots or narrow yellow band on anterior part. SIMILAR SPECIES The only Chrysotoxum with tergite 3 black or with much reduced markings compared to tergites 2 and 4; a roughly similar pattern occurs in Dasysyrphus tricinctus, but that species has much shorter antennae. OCCURRENCE Widely distributed, less localised than other Chrysotoxum but usually in low numbers. ECOLOGY Tall, scrubby grasslands near forest or scrub, also road verges and arable margins, often where Lasius nest mounds are common. Frequently visits umbellifers such as hogweed but also lower-growing flowers such as those of Black medick, Oxeye daisy. Larval biology unknown, possibly

associated with ant-tended aphids, and has been reared on a diet of aphids in the laboratory.

Hook-banded Meadow Fly Chrysotoxum festivum IDENTIFICATION 12–15 mm. A fairly large, elongated and dark

Chrysotoxum. Antennae longer than head; third antennal segment shorter than first and second antennal segments combined. Katepisternum usually with yellow spot, together with yellow spot above it forming an exclamation mark. Wing: below pterostigma with, sometimes indistinct, dark brown spot. Fore and mid femora without black base, either entirely yellow or with base orange to brown; seldom with a black smudge but if present, often restricted to one side. Tergites 2–4 with pairs of yellow stripes reaching side margin; posterior margin of tergites 2–4 black or with narrow yellow marking not connected with pair of stripes. SIMILAR SPECIES Similar to dark specimens of C. elegans, but in that species paired yellow spots on tergites 2–4 reach side margin. With C. vernale, the only Chrysotoxum with paired yellow spots on tergites 2–4 not reaching side margins, rendering its first impression dark. Usually larger than C. vernale and pairs of stripes on abdomen on average more curved. Leg base coloration is most reliable character: fore and mid femora entirely yellow or with very little black at base in C. festivum, in C. vernale at least basal

fifth black. Generally, katepisternum with yellow mark, absent in C. vernale, although this character is variable and not fully reliable. OCCURRENCE Widespread but infrequent, occasionally common. ECOLOGY All sorts of grassy situations near scrub or forest on different soil types. Adults characteristically hover at a height of 0.5–1 metre above the ground and are difficult to catch. Larval biology poorly known, but the larva has been found in a nest of the ant Lasius niger.

Smooth-banded Meadow Fly Chrysotoxum vernale IDENTIFICATION 11–12 mm. A dark Chrysotoxum. Antennae

longer than head; third antennal segment shorter than first and second antennal segments combined. Katepisternum black, without yellow mark. Wing: below pterostigma with, sometimes indistinct, dark brown spot. About basal one-fifth to one-third of fore and mid femora black. Tergites 2–4 with pairs of yellow stripes not reaching side margin; posterior margin of tergites 2–4 black or only narrowly yellow, not connected with pair of stripes. SIMILAR SPECIES For differences with other Chrysotoxum except C. festivum, see C. festivum. Like C. festivum but usually slightly smaller and stripes on abdomen less curved; most reliable character is base of fore and mid femora: black for at least a fifth in C. vernale, femora all yellow in C. festivum or with only very little black at base. The yellow mark on katepisternum is usually absent in C. vernale, usually present in C. festivum, but be aware, this character in not diagnostic – some C. vernale bear the mark and it is absent in some C. festivum. OCCURRENCE Widespread but very localised, usually in low numbers except at hill-tops.

ECOLOGY Much more selective than C. festivum: dry heathlands

and well-drained unimproved grasslands on sand or chalk. A strong hill-topper. Egg-laying females have been observed around the entrance of ant nests of the genus Lasius. As with other Chrysotoxum, the larva is suspected to feed on ant-tended root aphids.

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a b d o me n l a te ra l

♂

bl a ck ba nd uni nte rrupte d

♀

a b d o me n

ant enna bl a ck -ha i re d

♀

3 rd s e gme nt s horter th a n 1 s t a nd 2 nd co m bi ned

sc u te l l u m

a n te n n a

♂ 3 r d se gm e nt sho rte r tha n 1 st a nd 2 n d co m bi ne d

♂

a b d o me n l a te ra l

bl a ck ba nd i nte rrupte d

♀

♂

a b d o me n

ye l l o w ba nds re a ch si de m a rgi n

pa rtl y ye l l o w -ha i re d ant enna

♀

sc u te l l u m

3 rd s e gme nt s horte r th a n 1 s t a nd 2 nd com bi ned

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Verrall’s Meadow Fly Chrysotoxum verralli IDENTIFICATION 10–13 mm. Part of a difficult-to-identify trio with C. elegans and C. octomaculatum. Antennae longer than head; third antennal segment shorter than first and second antennal segments combined. Anterior margin of yellow markings on tergite 2 straight and parallel with anterior margin of tergite, except on outer sixth of their width, where they abruptly bend backwards; black anterior stripe on tergites 3 and 4 runs continuously to side margin. Female: scutum mainly with black hairs; top of scutellum covered entirely with black hairs. SIMILAR SPECIES Only C. elegans (variation with extensive yellow), C. octomaculatum and C. verralli share combination of extensive yellow markings on abdomen and third antennal segment shorter than first and second antennal segments combined. C. verralli with black anterior band on tergites 3 and 4 uninterrupted, bands in C. octomaculatum are interrupted just before side margin. Furthermore, female C. verralli with more extensive covering of black hairs on scutum. Distinctly smaller and

less elongate than C. elegans but similar to C. octomaculatum in shape and size. For more differences with C. elegans, see that species. OCCURRENCE May be increasing in Great Britain and on the continent (northern Belgium). Widespread but localised, locally numerous. ECOLOGY Grasslands in or near forest or scrub, forest clearings, often on marshy ground and near streams; generally, in more damp situations than other Chrysotoxum, except in Great Britain, where found in dry scrubby grassland. Adults often fly slowly through low vegetation looking like a small worker social wasp. Larva possibly associated with the ant Lasius niger, feeding on ant-attended root aphids.

Broken-banded Meadow Fly Chrysotoxum octomaculatum IDENTIFICATION 10–13 mm. Much like C. verralli and light morph

of C. elegans. Antennae longer than head; third antennal segment shorter than first and second antennal segments combined. Anterior margin of pair of yellow stripes on tergite 2 convex, parallel with anterior margin of tergite only for about half of its width, whereafter it gently bends backwards towards sides; black anterior stripe on tergite 4 and generally also tergite 3 interrupted just before side margin by a small yellow longitudinal stripe; abdomen with very short hairs, appearing almost bare. Female: scutum mainly with yellow hairs. SIMILAR SPECIES Only C. verralli and C. elegans share the combination of extensive yellow markings on abdomen and third antennal segment shorter than first and second antennal segments combined; most important character to distinguish C. octomaculatum from these two is the small yellow longitudinal stripe on tergites 3 and/or 4 that interrupts black anterior band just before side margin. Yellow stripe is diagnostic but it can be narrow or dark and difficult to see. Female C. octomaculatum has more pale hairs on scutum compared to C. verralli. OCCURRENCE A rare and very local species

in North-west Europe. ECOLOGY Dry heathlands, open forest on acidic soil near heathlands. Males fly or sit a few metres above the ground along forest edges and bushes at the edge of heaths. Females fly low and quickly through the vegetation. Visits flowers including those of buttercup, dandelion, Common heather and Alder buckthorn. Larval biology unknown.

Variable Meadow Fly Chrysotoxum elegans IDENTIFICATION 12–14 mm. Very similar to C. verralli and

C. octomaculatum. Extent of yellow markings is quite variable, making dark specimens much easier to identify than light morphs. Antennae longer than head; third antennal segment shorter than first and second antennal segments combined. Anterior margin of yellow markings on tergite 2 convex, only roughly parallel with anterior margin of tergite for at most half of their width, curving gradually backwards; black anterior stripe on tergites 3 and 4 runs continuously to side margin, not interrupted by yellow stripes. Female: scutellum partly covered with yellow hairs. SIMILAR SPECIES Could be confused with dark specimens of C. festivum and C. vernale; see former. Resembles C. verralli and C. octomaculatum, but larger; for reliable identification from C. octomaculatum, see that species. Compared to C. verralli, yellow stripes on tergite 2 with more convex anterior margin, but difference can be difficult to discern – a reference collection will help to understand this subtle character. In addition, females have more yellow hairs on scutellum and habitat differs.

OCCURRENCE Very rare and very local in the continental range covered in this book, but widespread in the south of Great Britain and possibly expanding. ECOLOGY Open forests and unimproved grasslands and heaths with extensive scrubs on well-drained soils. Flies low and quickly through vegetation and often visits flowers. Larva described from under a stone in grassland; almost certainly aphid-feeding, probably on root aphids.

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a b d o me n

♂

♀ ora n ge b a nds wi d e i n su m m er genera ti o ns

e a rl y spri ng a nd a utum n ge ne ra ti o ns da rke r

♀ ♂

a b d o me n

a b d o me n

ye l l o w spo t w i de a t ba se

♀

face

l unul e bl a ck

♀ a b d o me n maculicornis ♂

♂

a b d o me n auricollis

v ar iat io n maculicornis sl e nde r

♀

face

l unul e ye l l o w

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Marmalade Hoverfly Episyrphus balteatus IDENTIFICATION 8–12 mm. One of our most well-known hoverflies. Anterior part of scutum with three longitudinal grey dust stripes coalescing on posterior side in an extensive grey area. Tergites 3 and 4 with two orange (resembling the colour of marmalade) bands, divided by two black bands, width of orange bands very variable; early-spring and autumn generations often darker with narrower and darker orange bands and wider black to lead-grey bands, summer generations brighter orange with narrower black bands. SIMILAR SPECIES A very distinctive species, owing to unique pattern on abdomen, so not easily confused with other species. OCCURRENCE One of the commonest hoverflies. Overwinters as adult female, emerging on mild winter days and can hence be found almost year-round. Displays massive yearly influxes from southern Europe during the summer months; during such periods it can be extremely abundant and appear at unexpected locations such as at sea. ECOLOGY Any habitat, including urban environments. Perhaps most abundant at forest

and scrub edges. Males hover at sheltered places, often in partial shade, for example above forest paths. Forages on a tremendous variety of flowers, spring blossoms, also Ivy in autumn, and will regularly visit shaded flowers. Larva feeds on aphids on different plants and trees.

Banded Thintail Meliscaeva cinctella IDENTIFICATION 8–10 mm. Slender species with yellowish bands on abdomen. Lunule black; upper part of third antennal segment dark, orange below. Scutellum with black hairs. Pair of spots on tergite 2 rounded, large and wide; posterior margin of bands on tergites 3 and 4 without deep V-shaped incision in middle. SIMILAR SPECIES Owing to elongated, slender abdomen with bands on tergites 3 and 4, confused mainly with Fagisyrphus cinctus and the palest examples of M. auricollis; differs from F. cinctus by blunt inner side of spots on tergite 2, black lunule, black hairs on scutellum and dark upper part of third antennal segment; differs from banded morph of M. auricollis by having larger spots on tergite 2, black lunule, bands on tergites 3 and 4 with less deep incision on posterior margin and alula more elongated. OCCURRENCE Widespread and locally (very) common in North-west Europe, but has recently drastically declined in northern Belgium and has disappeared from several regions. Distinctly sporadic in abundance in the British Isles. ECOLOGY A species of damp forests, parks and gardens. On drier mainland, appears to be essentially linked to larger, colder and damper

forests; in Great Britain, seemingly less selective. Visits flowers in forest edge, often on white umbellifers; males hover several metres above the ground in sheltered places. Larva feeds on arboreal aphids.

Spotted Thintail Meliscaeva auricollis IDENTIFICATION 7–11 mm. A variable species. Frons above lunule black, lunule itself yellow; upper part of third antennal segment dark, orange below. Scutellum with black hairs. Spots on tergite 2 usually resembling oblique commas, not reaching side margin, but sometimes larger and bluntly triangular, reaching side margin; markings on tergites 3 and 4 variable, ranging from pairs of oblique spots with straight posterior margin (variation maculicornis) to bands with deep V-shaped incision on posterior margin (variation auricollis), with all possible intergrades. SIMILAR SPECIES Variation maculicornis: with spots on tergites 3 and 4 oblique and with straight posterior margin, distinguishing it from all similar species except Meligramma triangulifera; distinguished from that species by spots on tergites 3 and 4 not reaching side margin, anterior corners of scutellum yellow and female with larger dust spots on frons. Variation auricollis: like M. cinctella but lunule yellow, bands on tergites 3 and 4 with deeper incision on posterior margin and spots on tergite 2 almost always smaller. Like Fagisyrphus cinctus but spots on tergite 2

blunt, scutellum with black hairs and upper side of third antennal segment dark. OCCURRENCE Widespread and very frequent, also in urban environments. Variation auricollis typically occurs only in the summer generation. Often on the wing both very late and very early in the year, suggesting hibernation. ECOLOGY In a variety of habitats but often near broad-leaved trees or scrub, often relatively commoner in urbanised park-like areas than in natural forests. Males hover 2–5 metres above the ground. Visits flowers of many plant species. Larva feeds on aphids on herbs, bushes and trees.

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pale s pots, although i n ♂ ofte n le s s dis tinct as de picte d here

a b d o me n

w hi ti sh spo ts

♀

a b d o me n

♂ tri a ngul a r spo ts

tri a ngul a r spo ts

♂

♀

face

f a ce ye l l o w

head

♀

a b d o me n

♂

sl e nde r spo ts o r ba nds

scu tel l u m b l a ck

s mall, s le nder, fragile s pe cies

♂

♀

fa c e

face

sl ender spo ts or ba nds

face black

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Spotted Roundtail Meligramma guttata IDENTIFICATION 7–9 mm. A small and slender species. Face entirely

yellow; antennae black. Scutum along its posterior margin usually with characteristic pair of yellow spots; spots may be absent or fused into one larger spot, former mainly occurring in male; sides of scutum yellow, especially distinctive in female; scutellum partly with black hairs. Legs mainly brown. Abdomen with pairs of small white (females) to light yellow (males) rectangular spots with rounded corners, not reaching anterior and side margins. SIMILAR SPECIES Spots along posterior margin of scutum characteristic; if spots absent, can be confused with Melangyna, but face entirely yellow. Some specimens of M. triangulifera with spots along posterior margin of scutum, but that species has paler fore tarsus, paler antennae and yellow hairs on scutellum. OCCURRENCE Widespread, but scarce and unpredictable. ECOLOGY Wet broad-leaved forests, forested river valleys, parks. Flies among herbs and visits mainly white umbellifers. Larva feeds on arboreal aphids and has been found on sycamore.

Triangle-spotted Roundtail Meligramma triangulifera IDENTIFICATION 8–10 mm. Slender unobtrusive species resembling Platycheirus. Face white–yellow with yellow facial tubercle; third antennal segment brown, orange below. Scutellum with yellow hairs; anterior corners of scutellum black. Fore tibia and fore tarsus yellow. Tergites 3 and 4 with yellow to orange, more-or-less triangular spots on anterior part; spots typically reach side margin, sometimes not in male. Female: frons shiny black with small dust spots along eye margin; sides of scutum yellow. SIMILAR SPECIES Like Meliscaeva auricollis, but pairs of spots on abdomen reach side margin, anterior corners of scutellum black and female with yellow sides on scutum and smaller dust spots on frons. Can be confused with Platycheirus but scutellum yellow. Differs from Melangyna by its yellow facial tubercle, from M. guttata by more triangular and differently coloured spots on abdomen, yellow fore tibia and fore tarsus, partly pale antennae and yellow hairs on scutellum. Also see Epistrophella euchroma. OCCURRENCE A widespread forest species in Western Europe, but often overlooked owing to its secretive behaviour. ECOLOGY Broad-leaved forests, parks and gardens. Visits flowers,

mainly of white umbellifers and flowering scrubs and trees such as hawthorn, Wild crab and Field maple, but also frequently found sitting on tree leaves in forest edge. Larva preys on aphids on herbs, bushes and trees.

Needle Roundtail Meligramma cingulata IDENTIFICATION 7–9 mm. A small slender dark and unobtrusive

species. Face and frons entirely black, although face sometimes with some yellow markings along eye margin; third antennal segment orange below. Scutellum black, at most with a faint yellow tinge on top. Pairs of spots on tergites 2–4 yellow or whitish, narrowly triangular with pointed inner side, sometimes fused to a narrow band, especially in female. SIMILAR SPECIES Black face and scutellum makes this an atypical Meligramma; can be confused with Melanostoma or Platycheirus, but markings on abdomen differ from those on all known Platycheirus, and males without modified fore leg (distinguishing it from many Platycheirus). Once recognised as a Meligramma, identification easy: combination of black face, black scutellum and colour pattern on abdomen distinguishes it from all other Meligramma and allies. OCCURRENCE In Western Europe, restricted to low mountain ranges with spruce or fir plantations. Not known from Great Britain. ECOLOGY Mixed and coniferous forest with spruce or fir. Flies around trees, often a few metres

above the ground. Males hover high in sunny places in forest, 3–4 metres above the ground, or sit on tree leaves. Females have been collected on flowers of willows and sycamore. Larval biology unknown.

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♀

♂

pte ro sti gm a l o ng a nd bl a ck

tergi te 2 bl a ck

a bdo m e n bl a ck

♂

♀

fac e

♂

head

head

wi th o ut dust spo ts

pre do m i na ntl y pa l e -ha i re d

fa ce bl a ck

♂

sc u tu m

♀

a b d o me n

♂

♂

face

tergi te 2 bl a ck

♀

♂

head

head f a ce w i de a nd bl a ck

pre do m i na ntl y bl a ck -ha i re d wi th o ut dust spo ts

♂

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scutu m

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Black Halfband Melangyna quadrimaculata IDENTIFICATION 7–10 mm. A very dark Melangyna. Face black, with long hairs. Scutellum black but middle has a dark-yellow tinge. Legs black. Abdomen with paired yellow spots on tergites 3 and 4 in male, usually all black in female. Male: eyes with dense white hairs; scutum with pale hairs; sides of tergite 2 mostly with black hairs. Female: eyes with short hairs; frons unusually wide and shiny, sometimes with faint dusting but without distinct dust spots; wing pterostigma long and black; abdomen black, tergites 3 and 4 usually black with grey dusting on anterior half, very rarely with minute dark orange spots. SIMILAR SPECIES Male: only M. barbifrons also lacks spots on tergite 2, but M. quadrimaculata distinguished by pale hairs on scutum and hairs on eyes; male M. pavlovskyi has spots on tergite 2 sometimes very faint, but sides of tergite 2 have pale hairs. Female: unique in tribe Syrphini in having abdomen entirely black; however, some (possibly genetic) defects may cause other species to have a black abdomen as well. Female Parasyrphus punctulatus frequently have a black abdomen, but lack long black pterostigma and black legs of M. quadrimaculata; Pipiza and allies have no facial tubercle; Cheilosia species have orbital strip; dark or melanistic individuals of Platycheirus or Melanostoma have (partly) orange legs and no black pterostigma. Female M. quadrimaculata with small orange spots recognisable by long black pterostigma and black face. OCCURRENCE Widespread but often overlooked owing to early flight period. It is the earliest of those species that do not hibernate as adults, emerging in mild winters from the end of January! ECOLOGY Near mixed and coniferous forests, also at

small forest fragments and parks. Usually found visiting earlyflowering bushes and trees such as Common hazel, willow and Blackthorn. Often basks on tree trunks. Larva has been found with aphids on spruce but more likely prefers aphids on pines and Larch.

April Halfband Melangyna barbifrons IDENTIFICATION 7–10 mm. A small dark Melangyna. Face

wide; eyes bare. Sides of scutellum black. Abdomen with pairs of yellow spots, in male on tergites 3 and 4, in female on tergites 2–4. Male: face black; hairs on scutum mostly black; pairs of spots on tergites 3 and 4 small, slightly tapering inwards. Female: frons wide, without or with indistinct small dust spots. SIMILAR SPECIES Male very similar to M. quadrimaculata, but eyes without hairs and scutum mostly with black hairs; head proportionally bigger and wider, thus more top-heavy. In M. pavlovskyi, spots on tergite 2 may be almost absent, but that species has hairs on eyes, face narrower and sides of tergite 2 with pale hairs (black in M. barbifrons). Female differs from all other Melangyna with yellow spots on abdomen by wide frons without or with small indistinct dust spots. OCCURRENCE Widespread but very infrequent, scarce and few recent records. ECOLOGY Near large, mature Scots pine forests. Mainly found on willow catkins. Larval biology unknown, but probably feeds on aphids on pines.

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♀

mi d ti b i a

da rk

♂ ♀

a b d o me n

spo ts re cta ngul a r

app rox. 90°

♂

♀

♂

head

♀

f ace

head

face

si des scute l l um e x te nsi v e l y bl a ck

d ust spo ts

♂

scutu m

♂

♀

a b d o me n

w hi ti sh spo ts

♂

♀

head

♂

♀

f ace

scutum shi ny

head

sm a l l bl a ck spo t

l a rg e d ust spo ts

♂

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face

scutum

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Spring Halfband Melangyna lasiophthalma IDENTIFICATION 8–10 mm. Face distinct, yellow with dark medial stripe; eyes with hairs, sometimes sparse in female. Scutum shiny, with pale hairs; scutellum with black wedge-shaped side spots. Tergites 2–4 with pairs of yellow rectangular spots with faint dusting; sternites 3 and 4 black with pair of yellow spots in anterior half. Male: eyes meeting at a right angle; hind tibia nearly entirely black; spots on tergites 3 and 4 not reaching side margin. Female: frons with narrow band of dusting which is often interrupted in middle; mouth edge black in middle, yellow at sides; basal part of cell bm bare (without microtrichia); mid tibia with dark ring or with dark markings on outer side; spots on tergites 3 and 4 often reach side margin; sternites thinly and patchily dusted, appearing brightly shiny from some angles. SIMILAR SPECIES Often found with the very similar Parasyrphus punctulatus. Shape of yellow spots on tergites 3 and 4 subtly different: more rectangular, not or in a straight line connected to side margin, and in P. punctulatus spots have a convex posterior margin and bend towards anterior corners. Also M. lasiophthalma has sides of scutellum mostly black instead of mostly yellow, has third antennal segment always black instead of often orange below and markings on sternites of different shape, i.e. not triangular black marks of P. punctulatus. In male, combination of spots on tergite 2, partly yellow face, pale hairs on scutum and sides of scutellum extensively black distinguish it from all other Melangyna except M. lucifera; differs from that species by eyes meeting at a smaller angle, spots on tergites 3 and 4 more rectangular and with less dusting, and hind tibia entirely black. Female shares combination of narrow dust band on frons and

black sides of scutellum with M. lucifera but spots on tergites 3 and 4 more rectangular and with less dusting, and mid tibia usually with much clearer dark ring. OCCURRENCE A widespread and common spring Melangyna. ECOLOGY Near both broadleaved and coniferous forests, also in parks and gardens. Often visits willow catkins and Blackthorn blossom. Often basks on tree trunks. Larva feeds on aphids.

Shiny-backed Halfband Melangyna umbellatarum IDENTIFICATION 9–12 mm. A fairly large Melangyna with white

to white–yellow spots on abdomen. Face white–yellow with narrow dark medial stripe; eyes bare. Scutum shiny, black in male and blue–black in female; scutum usually with pale hairs; sides of scutellum with small round black spot at base. Wing: at least half of cell bm bare. Tergites 2–4 with pairs of spots, pale yellow in male, whitish in female; spots on tergites 3 and 4 rectangular with rounded corners. Female: frons directly behind lunule shiny, enclosed by wide, (nearly) connected dust spots; anterior corners of scutum dusted between postpronotum and transverse suture; pale spots on tergite 2 reaching anterior corner of tergite. SIMILAR SPECIES Distinguished from all Melangyna by small round black spots on sides of scutellum, except M. compositarum and M. ericarum. Differs from M. compositarum by its shiny scutum, large bare area at base of cell bm, males with denser hairs on eyes and female with shiny frons above lunule; differs from M. ericarum by pale hairs on scutum, largely shiny sternite 2 and larger area of cell bm bare. In female, pale spots on tergite 2 reaching anterior corner of tergite is a helpful character for distinguishing it from several similar species, including M. lasiophthalma and M. ericarum. OCCURRENCE Widespread but rarely common. ECOLOGY Less restricted to forests than many other Melangyna. Usually in umbellifer-rich grasslands and forest clearings. A strong hill-topper. Mostly visits tall white umbellifers, including Common hogweed and Wild angelica. Larva feeds on aphids.

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♀

♂

head

f ro ns a l m o st e nti re l y duste d

♂

♀

head

fac e scutum dul l

sm a l l bl a ck spo t

♂

scutum

wi n g d e ta i l

♂

♀

abdome n

ba se ce l l bm ba re

♀

head

l a rge dust spo ts o r ba nd

sm a l l bl a ck spo t

♂

scu tu m

wi n g d e ta i l

♂

ce l l bm co m pl e te l y co v e re d w i th m i cro tri chi a

♀

♂

fac e

♀

f ace

bl a ck -ha i re d

♂

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sc u tu m

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Matt-backed Halfband Melangyna compositarum IDENTIFICATION 9–11 mm. A fairly large Melangyna with paired

yellow spots on abdomen. Face white–yellow with dark medial stripe. Scutum dull and with pale hairs; sides of scutellum with small rounded black spot at base. Wing: cell bm entirely or almost entirely covered with microtrichia. Abdomen with pale-yellow paired spots on tergites 2–4; spots on tergites 3 and 4 rectangular with rounded corners. Male: eyes with short and sparse hairs, easily missed in some (older) specimens. Female: frons almost entirely dusted. SIMILAR SPECIES Easily confused with M. umbellatarum and M. ericarum owing to similar small black spot at side of scutellum, but scutum completely dusted and cell bm covered entirely with microtrichia. OCCURRENCE A common summer species in Britain, in contrast to nearby mainland Europe where it is rare or absent over large expanses and largely restricted to lower mountain ranges. ECOLOGY Near forests, both coniferous and broad-leaved, although curiously regionally may be restricted to one of either forest types. Males

hover along forest edges. Mostly visits tall umbellifers including Common hogweed, Wild parsnip and Wild angelica. Larval biology unknown. COMMENT Sometimes M. labiatarum is recognised as a separate species. Often indistinguishable from M. compositarum, but eyes in male with denser hairs. Other characters are unreliable, so that M. labiatarum is increasingly regarded as a synonym of M. compositarum, an approach that we also follow here.

Pinewood Halfband Melangyna ericarum IDENTIFICATION 8–10 mm. A relatively small and rather hairy

Melangyna with paired yellow spots on abdomen. Face partly yellow; eyes bare. Scutum shiny except front corners, which are heavily grey-dusted between postpronotum and transverse suture; scutellum with black wedge-shaped side spots. Wing: up to basal half of cell bm bare. Abdomen with pairs of yellow spots on tergites 2–4; spots on tergite 2 not reaching side margin; sternites lightly but uniformly dusted over entire surface. Male: most hairs on at least posterior part of scutum dark; many hairs on scutellum longer than scutellum. Female: frons in front of vertex extensively dusted, border between dusted frons and shiny black vertex clear-cut; pale spots on tergite 2 set back from anterior margin of tergite for a noticeable distance. SIMILAR SPECIES Male: combination of yellow spots on tergites 2–4 and small spots at anterior corner of sides of scutellum distinguishes it from all other Melangyna except M. compositarum and M. umbellatarum but former has cell bm covered entirely with microtrichia and latter has all hairs on scutum usually pale and sternite 2 largely undusted; in M. ericarum, hairs on posterior part of scutum partly

black and sternite 2 dusted. Female: combination of frons with wide dust spots or band and sides of scutellum with only small spots at anterior corners is shared only with M. compositarum and M. umbellatarum; differs from M. compositarum by shiny scutum and partly bare cell bm of wing; differs from M. umbellatarum by dusted sternite 2 and smaller spots on tergite 2 not reaching anterior and side margins; unlike M. lasiophthalma, eyes bare, anterior corners of scutum with dense instead of light dusting, spots on tergite 2 further removed from side margin and sternites more dusted. OCCURRENCE A rare and poorly known species; occurs in Scandinavia, Scotland and locally in Central Europe, mainly in mountain ranges. ECOLOGY Coniferous forests, humid Scots pine forest. Flies fast and low over sparsely vegetated ground, settling on flowers. Males hover above forest tracks. Larval biology unknown.

Alder Halfband Melangyna arctica IDENTIFICATION 8–10 mm. Eyes bare. Scutum shiny in male, but female with dusted front corners between postpronotum and transverse suture; scutellum with black wedge-shaped side spots. Wing: cell bm covered entirely with microtrichia. Abdomen with pairs of yellow spots on tergites 2–4, in male spots on tergite 2 rather small. Male: face entirely black or with yellow sides, often difficult to see because heavily dusted; most hairs on at least posterior part of scutum dark; hairs on scutellum not longer than scutellum. Female: frons with wide band of dusting with diffuse posterior margin; most of scutum with pale hairs, but with band of dark hairs between wing bases, sometimes restricted to sides; sternites densely dusted. SIMILAR SPECIES Male: with M. ericarum, the only Melangyna with combination of three pairs of spots on abdomen and at least posterior part of scutum with black hairs; differs from M. ericarum by cell bm entirely covered with microtrichia, hairs on scutellum shorter and front corners of scutum less densely dusted. Female: distinguished from other Melangyna by combination of complete dust band

on frons, bare eyes, dusted sternites and scutellum with black wedge-shaped side spots; differs from M. ericarum by cell bm entirely covered with microtrichia and sides of scutellum with wedge-shaped instead of small rounded spots; unlike M. lucifera and M. pavlovskyi, scutum covered partly with black hairs. OCCURRENCE In mainland Europe, restricted to Central European high mountains and Scandinavia but absent in the range covered by this book; in Great Britain, mainly in cooler and more humid districts in the north and in the lower mountains. ECOLOGY Forests, both coniferous and broad-leaved, also in more open habitats with scattered scrubs. Visits flowers of willow and Blackthorn, also low-growing plants such as Common tormentil. Larva has been found near aphids on Common alder.

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a b d o me n

spo ts ta pe ri ng i nwa rds

♂

♀

mi d ti b i a

pa l e

♂

approx. 1 2 0 °

♂

♀

f ace

face

head f a ce w i de

♀

head

w e dge -sha pe d spo t

d ust spo ts

♂

sc u tu m

♂ ♀

a b d o me n

s pot s mall and ro unded spo ts na rro w

♂

head

♀

head

♂

♀

f ace

face

m o uth e dge bl a ck dust spo ts na rro w

♂

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scu tu m

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Silver Halfband Melangyna lucifera IDENTIFICATION 8–10 mm. A Melangyna similar to

M. lasiophthalma. Face wide, with dark medial stripe. Scutum with pale hairs; scutellum with black wedge-shaped side spots. Tergites 2–4 with pairs of yellow spots covered in silvery dusting (best seen from oblique angle); spots on tergites 3 and 4 widest halfway along their length and pointed inwards (males) or gradually tapering inwards (females). Male: eyes with sparse hairs; eyes meeting at an obtuse angle, approximately 120°; basal half of hind tibia yellow–brown. Female: mouth edge partly yellow; eyes with short sparse hairs; frons with narrow dust band, often interrupted in middle; cell bm covered entirely with microtrichia; mid tibia yellow. SIMILAR SPECIES Pairs of dusted spots on tergites 3 and 4 which taper inwards are a reliable but sometimes subtle character distinguishing it from all other Melangyna. Male otherwise like M. lasiophthalma but face wider, so angle at which eyes meet larger, and basal half of hind femur paler. Female compared to M. lasiophthalma with wider face, entirely pale mid tibia and cell bm covered entirely with microtrichia. OCCURRENCE Northern and Eastern Europe, regular sightings south to Denmark, but recently also repeatedly found in Belgium and the Netherlands. Not known from Great Britain. ECOLOGY Presumably comparable with M. lasiophthalma. Visits flowering willow where it can be found amongst other Melangyna species. Larval biology undescribed.

Sakhalin Halfband Melangyna pavlovskyi IDENTIFICATION 7–10 mm. A dark Melangyna with light hairs.

Eyes with long white hairs. Scutum covered entirely with pale hairs; sides of scutellum completely black. Abdomen with pairs of small rectangular spots on tergites 3 and 4, those on tergite 2 rounded and small, sometimes absent in male. Male: face black; sides of tergite 2 with white hairs, spots on abdomen heavily dusted. Female: face black with indistinct yellow spots, mouth edge entirely black; frons with narrow but distinctive dust spots; gives a dark impression owing to small rounded spots on tergite 2 and narrow stripe-like pairs of spots with parallel sides on tergites 3 and 4; at least apical half of mid tibia dark; sternites entirely black. SIMILAR SPECIES Male: if spots on tergite 2 missing, white hairs on sides of tergite 2 distinguish it from M. barbifrons and M. quadrimaculata; if spots on tergite 2 present, it is the only Melangyna with combination of scutellum sides entirely black, black face and eyes with hairs. Female: shares combination of dust spots on frons, black sides of scutellum and hairs on eyes with M. lasiophthalma and M. lucifera but mouth edge black instead of partly yellow, sternites entirely black instead of with yellow spots, eyes with longer hairs and mid tibia darker. OCCURRENCE Until recently, known only from Russian Far East, but it has rapidly colonised the whole of Northern Europe and may appear in Great Britain. Now widespread and locally the commonest Melangyna in eastern Belgium. ECOLOGY Found at edge of mixed and coniferous forests, both spruce and pine. Visits willow catkins, Blackthorn, Common hazel and Cornelian cherry. Larval biology unknown, presumably feeds on conifer aphids.

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♀

a b d o me n

♂ spo ts tri a ngul a r

♀

head

♀

a b d o me n

♂

c a l yp te r

♂

♀

fac e

f ace uppe r surf a ce ha i re d

fa ce yel l ow, mouth ed ge b l a ck

♀ ♂

a b d o me n

ba nds re l a ti v e l y na rro w

♂

head

e ye s ha i re d

♂

hind femur

b l a ck-h a i red

♀

hind f emur bl a ck -ha i re d

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Ringed Beech Fly Fagisyrphus cinctus IDENTIFICATION 7–10 mm. A fairly small, slender species. Third antennal segment yellow. Scutellum with yellow hairs. Tergite 2 with pair of pointed triangular spots reaching side margin; tergites 3 and 4 with usually straight bands, posterior margin rarely with deep incision. SIMILAR SPECIES Pointed triangular spots on tergite 2 very characteristic. Owing to uninterrupted bands on tergites 3 and 4, similar to Meliscaeva cinctella, but in that species spots on tergite 2 point inwards less, frons above lunule black, antenna less extensively orange and scutellum with dark hairs. OCCURRENCE Widespread, occurring where European beech is present. Can be abundant in beech forest in spring. ECOLOGY Various habitats including broad-leaved forests and parks, often in the presence of European beech. Males hover 2–5 metres above the ground, often in dappled sunlight. Visits flowers of, for example, white umbellifers, and basks on sunlit tree foliage. Larva feeds on aphids, mainly on European beech. COMMENT Until recently, known under the name Melangyna

cincta. Looks, however, very different from Melangyna species and newest information from DNA research confirms that it branched off from Melangyna, making Fagisyrphus the preferred genus name.

Barred Flower Fly Syrphus nitidifrons IDENTIFICATION 7–10 mm. A small atypical Syrphus with pairs

of spots instead of bands on tergites 3 and 4. Frons shiny black; face yellow, facial tubercle sometimes dark; mouth edge broadly black; third antennal segment orange below; eyes bare. Scutum shiny; anterior anepisternum bare. Wing: upper surface of lower calypter haired, although less dense than in other Syrphus, sometimes only a few hairs present. Tergites 3 and 4 with pairs of narrow spots which sometimes meet in the middle; sternites with wide black bands. SIMILAR SPECIES Difficult to detect among the much commoner Melangyna lasiophthalma and Parasyrphus punctulatus, and often confused with these species. Unfortunately, two important diagnostic characters are not usable in the field: the haired upper surface of lower calypter excluding both species and the bare anterior anepisternum, haired in Parasyrphus. Also differs from P. punctulatus by yellow face (at most, facial tubercle dark), sternites with black bands over full width (smaller, triangular spots in P. punctulatus) and bare eyes in male. Differs from M. lasiophthalma by yellow face, partly pale third antennal segment and yellow fore and mid tibiae. Beware examples of

S. vitripennis with interrupted yellow bands on tergites 3 and 4. OCCURRENCE Has increased over the past decades in mainland North-west Europe; recently also discovered in Great Britain. ECOLOGY Mixed and coniferous forests (both spruce and pine). Forest glades, along tracks. Often visits flowering bushes and small trees such as willow, Blackthorn, hawthorn and rowan. Larval biology unknown.

Hairy-eyed Flower Fly Syrphus torvus IDENTIFICATION 9–13 mm. A quite large Syrphus. Face and

mouth edge yellow; third antennal segment orange below; eyes with hairs, but in female hairs may be sparse, best assessed using a hand lens and looking at an oblique angle and against a dark background (see photo). Scutum dull; tarsi largely dark above. Wing: upper surface of lower calypter with hairs; cell bm covered entirely with microtrichia. Abdomen with yellow bands on tergites 3 and 4; tergite 2 with pair of spots that bend to anterior corner just before side margin. Basal half to two-thirds of hind femur black; black hairs on upper side of hind femur tip, in the field a good hand lens is needed to assess this. Female: usually only basal half of hind femur black; bands on abdomen relatively slender. SIMILAR SPECIES Differs from Epistrophe by having hairs on eyes; for other differences with Epistrophe, see S. ribesii. Similar to S. ribesii and S. vitripennis but hairy eyes distinguish it from both, and bands on abdomen on average narrower; for additional differences, see S. ribesii and S. vitripennis. OCCURRENCE Generally, first Syrphus of the season, also the most spring biased but can

appear in summer and autumn. Every several years, it can be extremely abundant. ECOLOGY Found in various habitats, but most numerous in the vicinity of forest, forest edges, parks and gardens. Male hovering is less prolonged than in S. ribesii. Visits many different flowers but especially abundant on willow in spring. Larva feeds on aphids in bushes and trees.

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♀

a b d o me n

♂

♀

hind femur

a l l yel l ow

bl a ck-h a i red c a l yp te r

bl a ck-h a i red uppe r surf a ce ha i re d

♂

hind femur

♀

a b d o me n

♂

♂

hind fem ur

ye l l o w -ha i re d

♀

h i n d f e mu r ye l l o w -ha i re d

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Common Flower Fly Syrphus ribesii IDENTIFICATION 9–13 mm. One of our most familiar hoverflies. Face and mouth edge yellow; eyes bare, but males can have short scattered hairs, visible at high magnification; third antennal segment orange below. Scutum dull grey–green. Wing: upper surface of lower calypter with hairs; cell bm covered entirely with microtrichia. Abdomen with yellow bands on tergites 3 and 4; tergite 2 with pair of spots that sharply bend towards anterior corner just before side margin. Fore and mid tarsi with segments 3–5 black above. Male: hind femur black for basal two-thirds; upper side of hind femur tip with many adpressed black hairs, visible only with a good hand lens or very good photographs. Female: hind femur yellow. SIMILAR SPECIES Differs from Epistrophe by having hairs on upper surface of lower calypter, more yellowish instead of orange–yellow markings on abdomen and darker tarsi; males distinguished by largely black hind femur. Female easily distinguished from other Syrphus by yellow hind femur, however, see comment under S. vitripennis. Male like S. torvus, but eyes bare; like S. vitripennis, but upper side of hind femur tip with adpressed black hairs, cell bm covered entirely with microtrichia and hind femur usually less extensively black, yellow on apical third to half. OCCURRENCE One of the commonest hoverflies in North-west Europe. ECOLOGY Found in many habitats, including forests, parks, gardens, flowery roadsides. Males can be found in large numbers while hovering or settling on leaves in forests, 2–5 metres above the ground. This is the insect that can produce a strange humming sound in a forest during spring (apparently, males vibrating their wings while resting on foliage). Visits wide array of flowers. Larva feeds on aphids on different herbs, bushes and trees.

Black-thighed Flower Fly Syrphus vitripennis IDENTIFICATION 8–12 mm. A fairly small Syrphus with yellow

bands on abdomen. Face and mouth edge yellow; third antennal segment orange below; eyes bare. Scutum dull. Wing: upper surface of lower calypter with hairs; at least basal quarter of cell bm bare. Basal two-thirds to three-quarters of hind femur black; upper side of hind femur tip with yellow hairs, sometimes a few black hairs present, assessment in the field requires a good hand lens. Tergites 3 and 4 with yellow bands; tergite 2 with pair of spots that bend to anterior corner just before side margin. Tarsi of fore and mid legs often yellow, sometimes tarsi 3–5 somewhat dark in male. SIMILAR SPECIES Owing to small size, can be confused with Parasyrphus, for example, P. annulatus, but that species has face with a black medial stripe. Differs from Epistrophe by having black hairs on upper surface of lower calypter and basal two-thirds of hind femur. Very similar to S. ribesii and S. torvus but on average slightly smaller, hind femur more extensively black, upper side of hind femur tip with mainly yellow hairs and base of cell bm bare; easiest feature for distinguishing it from S. torvus, however, is its bare eyes; easily distinguished from female S. ribesii by largely black hind femur, for differentiating it from male S. ribesii, only usable field character is colour of hairs on upper side of tip of hind femur, but a strong hand lens and some practice is needed. Albeit not fully reliable, yellowish fore and mid tarsi are a useful first clue in the field that the specimen is S. vitripennis. OCCURRENCE Widespread and very common, relatively more common in summer compared to the other banded Syrphus. ECOLOGY Found in many habitats, but most numerous in open landscapes. Males hover 2–5 metres above the ground, for example, along forest edges. Visits flowers of various plant species. Larva feeds on aphids on herbs, bushes and trees.

COMMENT Very rarely, females with a yellow hind femur are found;

the best way to distinguish them from S. ribesii is the bare base of cell bm. These females fit the description of the Nearctic species Syrphus rectus; males of that species are indistinguishable from S. vitripennis. Females with a yellow hind femur in our region could be S. rectus or an undescribed species, but very likely are just a variation of S. vitripennis.

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a b d o me n

♂ o f te n w i th po i nte d ce ntre

ba nds re a ch si de m a rgi n na rro w l y a l l ta rsi bl a ck

a nte ri o r a ne pi ste rnum ha i re d

♂

♀

fac e

th o ra x l a te ra l

f ace

fa ce yel l ow, m o uth ed ge bl a ck

♀ ♂

a b d o me n

scu tu m sh i ny

a bdo m e n w i th ba nds

♂

f o re ta ru s

da rke ne d

dust spo ts sm a l l

♂

hind leg

♀

face

bas e tibi a p a l e

m e di a n stri pe o f te n f a i nt

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Black-footed Bristleside Parasyrphus nigritarsis IDENTIFICATION 7–10 mm. Identifying this species can be a challenge: looks like a Syrphus or Epistrophe species owing to orange bands on abdomen. Face yellow; mouth edge black; third antennal segment orange below; eyes bare. Scutum slightly shiny; anterior anepisternum with hairs. Wing: upper surface of lower calypter bare. Tarsi black. Tergites 3 and 4 with orange bands with undulating posterior margin; anterior margin of band on tergite 3 and usually also 4 with, mainly in male, pointed centre; bands on abdomen widest just before side margin, but narrowing abruptly and reaching side margin only narrowly in anterior corner; sides of tergites 3 and 4 with poorly developed ridge. Male: basal half of fore and mid femora black; over basal half of hind femur black; hind tibia yellow or with black ring. Female: base of femora narrowly black, remainder of femora and tibiae yellow, strongly contrasting with black tarsi. SIMILAR SPECIES Easily missed in the field because of strong resemblance to Syrphus, Epistrophe and other species of Parasyrphus. Always identified as Parasyrphus by hairs on anterior anepisternum, although a microscope is needed to assess this. Identified from other Parasyrphus with bands on abdomen by its combination of yellow face (but see P. malinellus), third antennal segment orange below and paler hind femur. Females most resemble Epistrophe (especially E. melanostoma and E. nitidicollis) owing to orange abdominal bands, but tarsi black and bands on abdomen not broadly reaching side margin. Like Syrphus, which also has dark tarsi, but distinguished by mouth edge being black, fore and mid tarsi not just dark but black and upper surface of lower calypter bare. OCCURRENCE Apparently eggs and larvae of P. nigritarsis are readily found; this, however,

cannot be said of adults; adults may be highly arboreal, spending most of their time high up in trees and bushes. ECOLOGY Wet montane and alluvial forests with poplars, willows or Common alder. A strong hill-topper. Visits various flowers. Unlike in other Parasyrphus species, larva feeds on larvae of leaf beetles such as Agelastica alni and Chrysomela vigintipunctata.

Smudge-faced Bristleside Parasyrphus malinellus IDENTIFICATION 8–9 mm. A Parasyrphus with yellow to orange– yellow bands on abdomen. Face with black medial stripe, sometimes faint or even absent; third antennal segment pale below. Scutum shiny; anterior anepisternum with hairs. Hind femur black with small yellow tip; hind tibia pale at base, otherwise black. Tergites 3 and 4 with yellow to orange–yellow bands. Male: at least basal half of fore and mid femur black; fore and mid tarsi dark, not black, but brown to black–brown. Female: frons with narrow dust spots; all femora black at base; fore and mid tarsi dirty yellow. SIMILAR SPECIES Due to bands on abdomen easily confused with Syrphus species but face usually with black medial stripe, scutum shinier, anterior anepisternum with hairs and upper surface of lower calypter bare. Could be mistaken for P. nigritarsis if black medial stripe on face indistinct, but hind tibia mainly black. Distinctive among other Parasyrphus by shinier scutum; differs further from P. lineola and P. relictus by third antennal segment paler below, from P. relictus by dark tip of hind tibia and from P. lineola by tarsi not being deep black. Like P. annulatus but scutum slightly shinier (subtle character), medial stripe on face usually fainter; also, male with fore and mid tarsi dark, female with base of femur 3 black and dust spots on frons smaller. OCCURRENCE Widespread but local and infrequent, but sometimes abundant in mature spruce plantations in low mountains. Has sharply declined in northern Belgium. A spring species that is rarely seen after the end of June. ECOLOGY Mixed and coniferous forests, mainly spruce plantations. Males hover along forest edges. Visits flowers of, for example, Bird cherry, Juneberry, Red elderberry and rowan. Larval biology unknown.

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♀

a b d o me n

face

♂ s cutum d ul l

♂

head

b a se ye l l o w yel l o w

♂

♀

fo re t ars us

3 r d a nte nna l se gm e nt pa l e be l o w

hind f emur

♀

fore and mid tars i gre y- ye llow

♀

a b d o me n

a b d o me n

♂

pte ros tigma ye llow- brown i n ♀ so m e ti m e s a bdo m e n bl a ck

♀

f ro n s

sm a l l d ust spo ts

ant enna

a ri sta red di sh, sh o rt a n d thi cken ed a t b a se

♂

fore and mid tars i black

♀

head

a b d o me n

♂ pte ros tigma dark brown

♀

ant enna

f ro n s

♂

head

l a rg e d ust spo ts

a ri sta b l a ck, l ong, na rro w a t b a se

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Yellow-footed Bristleside Parasyrphus annulatus IDENTIFICATION 6–8 mm. A small Parasyrphus with yellow bands

on abdomen. Face with distinct black medial stripe; third antennal segment orange below. Scutum dull; anterior anepisternum with hairs. Tibiae and tarsi of fore and mid legs bright yellow; hind femur in male black with pale tip, in female, black with pale base and tip; hind tibia with dark tip. Female: dust spots on frons large. SIMILAR SPECIES Can be mistaken for a small Syrphus, but face with dark medial stripe. Males differ from those of other Parasyrphus species with bands on abdomen by their combination of entirely yellow fore and mid tarsi and third antennal segment orange below; females by their combination of pale base and tip of hind femur and third antennal segment pale below. Especially female P. malinellus can have pale tarsi too, but not bright yellow, moreover, medial stripe on face of P. malinellus usually faint, scutum slightly shinier (difference often subtle) and female dust spots on frons smaller. OCCURRENCE On the continent infrequent and in low numbers in lowland pine forest, but very abundant

in low mountain-spruce plantations. Has declined in northern Belgium. ECOLOGY Mixed and coniferous forest, both pine forest and spruce plantations. Often visits flowering bushes and white umbellifers. Larva preys on aphids on coniferous trees.

Common Spotted Bristleside Parasyrphus punctulatus IDENTIFICATION 6–8 mm. A common Parasyrphus with spots on

abdomen. Face with black medial stripe; antennae brown–black, third antennal segment often slightly orange below; arista shorter than antenna, basal half reddish and thickened. Scutum dull; anterior anepisternum with hairs. Wing: pterostigma pale brown. Fore and mid tarsi grey–yellow to blackish. Tergites 3 and 4 with semicircular spots reaching side margin in tergite anterior corner; sternites with black triangular spots that do not, or only just, reach side margin. Male: hairs on eyes sparse; sides of scutum with yellow hairs. Female: eyes bare or nearly so; frons with two relatively small dust spots that do not connect or with only a small connection; vertex shiny, contrasting with dusted ocellar triangle; in spring, females with all-black abdomen common. SIMILAR SPECIES Very similar to P. macularis; for differences, see that species. Similar to Melangyna lasiophthalma; for differences, see that species. Females with black abdomen can be confused with female M. quadrimaculata, but yellow parts of face and sides of scutellum, and pale pterostimga distinguish P. punctulatus. OCCURRENCE Widespread and frequent, often a numerically

important member of the spring syrphid community in woodland. ECOLOGY Broad-leaved and coniferous forests, parks. Males hover some 2–3 metres above the ground along forest edges and glades or hill-tops, frequently settling on leaves. Often visits blossoms and catkins. Like other Parasyrphus, often comes down to drink at moist forest tracks during sunny days. Larva probably feeds on aphids.

Greater Spotted Bristleside Parasyrphus macularis IDENTIFICATION 8–10 mm. A somewhat bigger P. punctulatus

lookalike. Face with black medial stripe; antenna brown–black; arista long and thickened only in basal third, with thickened part dark, at most slightly reddish. Scutum dull; anterior anepisternum with hairs. Wing: pterostigma dark brown to grey–black. Fore and mid tarsi black. Tergites 3 and 4 with semicircular spots reaching side margin in tergite anterior corner. Male: eyes distinctly and densely covered with hairs; sides of scutum often with black hairs. Female: eyes with sparse but distinctive hairs; frons with two relatively large and broadly connected dust spots; vertex thinly dusted, only slightly contrasting with dusted ocellar triangle. SIMILAR SPECIES With P. punctulatus, the only Parasyrphus with spots instead of bands on tergites 3 and 4. Very similar to P. punctulatus but on average larger, pterostigma darker, hairs on eyes denser; fore and mid tarsi black; arista black, long and slender; male with black hairs on sides of scutum, female with vertex duller and frons with larger dust spots; too often not every feature leads to correct species, so use a combination of

features to get a certain identification. Can be confused with Melangyna; for differences, see M. lasiophthalma. OCCURRENCE A Scandinavian species that also occurs in Central European low and high mountain ranges. Not known from Great Britain. ECOLOGY Spruce forests. Often flies around spruce trees. Males hover 3–4 metres above the ground in sunlit parts of the forest and settle on spruces. Frequents mainly tree blossoms and catkins, but in their absence also on low flowers. Larval biology unknown.

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a b d o me n

♂

♂

f o re ta rsu s

hind leg

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a t l e a st 1 st se gm e nt ye l l o w

f ace

♂

ye llow ti p

head

dark ri n g

bl a ck m e di a n stri pe

♀

a b d o me n

♂ pte ro sti gm a da rk bro w n

♂

f o re ta rsu s

ta rsus bl a ck hind leg

♀

f ace

♂

head

le g black , a t mos t k ne e pa l e

3 r d a nte nna l se gm e nt bl a ck bl a ck med i a n stri p e

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Pine Bristleside Parasyrphus relictus IDENTIFICATION 8–10 mm. A Parasyrphus with yellow bands on abdomen. Face with black medial stripe; third antennal segment dark brown or blackish, often not completely black. Scutum dull; anterior anepisternum with hairs. Wing: pterostigma light brown or grey. At least tarsomere 1 of fore leg yellow, remaining tarsomeres dark; hind tibia yellow with black ring in middle, although tip sometimes also somewhat dark; approximately apical sixth of hind femur yellow. Tergites 3 and 4 with yellow bands. SIMILAR SPECIES Like a small Syrphus, but face with black medial stripe, anterior anepisternum with hairs and upper surface of lower calypter bare. Looks like a pale version of P. lineola owing to bands on abdomen and dark third antennal segment, but third antennal segment usually brown–black instead of black, pterostigma paler, fore tarsus and hind leg paler with hind tibia extensively yellow instead of black with narrow pale base. Specimens with seemingly intermediate characters (or not yet fully coloured specimens) occur, which are very difficult to identify. If third antennal segment appears pale, can be confused with Parasyrphus other than P. lineola, but hind tibia extensively yellow at base and tip, instead of tip dark or only narrowly yellow. OCCURRENCE Has dramatically declined over mainland North-west Europe in the past decades, now virtually extinct over most of the North-west European continental range. ECOLOGY Mainly coniferous forests, both pine and spruce forest, but sometimes also in broad-leaved forest. Larva feeds on aphids and is found on various coniferous trees, but also European beech. COMMENT Until recently mainly known under the name P. vittiger.

Dark-legged Bristleside Parasyrphus lineola IDENTIFICATION 8–10 mm. A Parasyrphus with yellow bands on abdomen and a distinctly dark pterostigma. Face with black medial stripe; third antennal segment black. Scutum dull; anterior anepisternum with hairs. Wing: pterostigma dark grey. Fore tarsus black; hind leg entirely black, at most knee pale. Tergites 3 and 4 with yellow bands. Female: frons with large dust spots. SIMILAR SPECIES Like a small Syrphus but face with black medial stripe, hind leg and pterostigma darker, anterior anepisternum with hairs and upper surface of lower calypter bare. Because abdomen with bands and dark third antennal segment, within Parasyrphus mainly confused with P. relictus, but darker: third antennal segment truly black, fore tarsus black, hind leg black except pale knee; not all characters always work and thus can be confusingly similar to P. relictus. Especially not-yet-fully-coloured specimens can have more brownish third antennal segment and tarsi, resembling P. malinellus, but scutum duller, face always with very distinct black median stripe and female has dust spots on frons larger. OCCURRENCE Widespread but localised, can be abundant in spruce plantations. Has strongly declined in northern Belgium. ECOLOGY As most other Parasyrphus mainly in mixed woodland and conifer (pine, spruce) plantations. Males hover several metres above the ground and settle on leaves or needles. Larva feeds on aphids.

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a b d o me n

♂

♀

a b d o me n

m a rk i ngs o n te rgi te 3 w i de r tha n o n te rgi te 4

♀

a b d o me n

spo ts re a ch si de m a rgi n

♂

♂

face

ant enna

a nten na b l a ck

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Stripe-backed Brusheye Dasysyrphus albostriatus IDENTIFICATION 8–10 mm. A distinctive and familiar hoverfly with two dusted white longitudinal stripes on anterior part of scutum. Face with black median stripe; eyes haired. Scutum blue–grey shiny; notopleuron with white dusting; postalar callus yellow. Tergites 3 and 4 with oblique yellow pairs of spots that usually meet and do not reach the side margin. In summer tends to have more extensive yellow on the tergites than in spring. SIMILAR SPECIES Combination of oblique yellow spots on abdomen and dusted white longitudinal stripes in anterior part of scutum unique in the region covered by this guide. OCCURRENCE Widespread and frequent yet never in high numbers. ECOLOGY Both broad-leaved and coniferous forests, also parks and gardens. Males hover under trees, often two to three metres above the ground, and settle on leaves. Visits a great diversity of flowers. Larva feeds on aphids on both broad-leaved and coniferous trees.

Yellow-girdled Brusheye Dasysyrphus tricinctus IDENTIFICATION 10–12 mm. Another distinctive Dasysyrphus.

Eyes with hairs; face with black medial stripe. Tergite 2 with pair of small stripe-shaped spots, sometimes absent; anterior part of tergite 3 with wide yellow band, may be interrupted in middle; anterior part of tergite 4 with pair of narrow yellow spots that almost meet; sternites with wide black bars. SIMILAR SPECIES One of the few hoverflies with yellow markings on tergite 3 distinctly wider than those on tergite 4. Looks superficially like Chrysotoxum bicinctum but antennae much shorter, amongst other differences. OCCURRENCE Widespread, fairly frequent but mostly in low numbers. ECOLOGY Broad-leaved and coniferous forests, heaths, gardens, often peaking late in the year. Visits flowers, including those of yellow composites, Field maple, Common heather and white umbellifers. Larva preys on aphids on, for example, maple.

Hook-banded Brusheye Dasysyrphus friuliensis IDENTIFICATION 10–12 mm. A robust Dasysyrphus with

comma-shaped bars. Eyes with hairs; antennae entirely black; face with wide black medial stripe. Tergites 3 and 4 with pairs of comma-shaped bars that reach side margin, posterior margins of bars almost straight, but anterior margin distinctly concave, creating sharply constricted bars that can be interrupted in middle; sternites 2–4 with large rectangular black bars that reach side margin. SIMILAR SPECIES Like D. venustus, D. hilaris and D. neovenustus with spots on abdomen that reach side margin, but larger, with entirely black antennae, pairs of spots on tergites 3 and 4 more constricted, and large black bars on sternites. Dark specimens (or species, see further) of D. venustus with quite constricted spots occur, so identification not always straightforward. OCCURRENCE Between c. 1960 and 1990, this species colonised much of North-west Europe, but has largely disappeared since. In Great Britain the first specimen was recognised in 1979, but current records are few and many (all?) relate to aberrant D. venustus. Possibly no longer present in the

range covered by this book. ECOLOGY Coniferous forests, both pine and spruce forests. Found along forest tracks, forest glades, etc. Visits various flowers including those of white umbellifers and buttercups. Larva preys on aphids. COMMENT Recent unpublished genetic research confirms D. friuliensis is a valid species. See also comment for D. venustus.

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a b d o me n

♂ spo ts w i th undul a ti ng f ro nt m a rgi n pte ros tigma dark

h i nd ti bi a da rk i n the m i ddl e

♂

o va l spo t

fac e

antenna bl a ck med i a n stri pe

♂ 3 r d a n ten na l seg m ent pa l e b el o w

♀

u n d e rsi d e a b d o me n

a b d o me n

♂ spo ts w i th stra i ght f ro nt m a rgi n pte ros tigma pale

h i nd ti bi a pa l e

♂

fac e

w i de re cta ngul a r spo t 3 r d a n ten na l seg m ent pa l e b el o w bl a ck med i a n stri pe

♂ ♂

head

♀

♂

♂

u n d e rsi d e a b d o me n

a b d o me n

spo ts re a ch si de m a rgi n

fac e sm a l l spo t

fa ce yel l ow

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u n d e rsi d e a b d o me n

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Broad-barred Brusheye Dasysyrphus venustus IDENTIFICATION 7–10 mm. A Dasysyrphus in which abdominal spots reach side margin. Face with black medial stripe; third antennal segment orange below; eyes with hairs. Wing: pterostigma brown. Hind tibia with dark ring in middle. Tergites 3 and 4 with constricted bars reaching side margin; sternite 2 usually with small rounded triangular black spot, but morphotypes exist with black bars reaching side margin. Male: basal three-quarters of hind femur black. Female: frons with pair of large and distinctive dust spots; basal two-thirds of hind femur black. SIMILAR SPECIES Like in D. hilaris, D. friuliensis and D. neovenustus, spots on abdomen reach side margin. Differs from D. friuliensis by having third antennal segment pale below and less constricted bars on tergites 3 and 4, but given variation in D. venustus, distinguishing between them not always easy. Like D. hilaris but face with distinct black medial stripe and sternite 2 usually with distinct black marking. For differences with very similar D. neovenustus, see that species. OCCURRENCE Widespread

and common around woodland. ECOLOGY Different types of broad-leaved forest, parks and gardens. Visits flowers of various plants, bushes and trees. Seems to prefer yellow flowers such as those of buttercup and broom. Larva preys on aphids. COMMENT Forms a species complex with D. hilaris, D. friuliensis and D. neovenustus. Research is ongoing; preliminary results suggest the complex contains more species and has a different arrangement than currently, with large taxonomic consequences. However, as this research is not yet published, we maintain the current arrangement to avoid confusion. See also comment for D. neovenustus.

Narrow-barred Brusheye Dasysyrphus neovenustus IDENTIFICATION 7–9 mm. A fairly small Dasysyrphus with

straight bars reaching side margin. Face with black medial stripe; third antennal segment orange below; eyes with hairs. Wing: pterostigma yellowish. Hind tibia yellow or with faint dark marking only. Tergites 3 and 4 with yellow bars reaching side margin, spots only a little constricted, so anterior margin almost straight; sternite 2 with black rectangular bar reaching side margin. Male: basal half of hind femur black; frons dark, lightly dusted. Female: frons with small indistinct dust spots; usually all femora yellow, abdomen distinctly shiny. SIMILAR SPECIES Combination of bars on abdomen reaching side margin, third antennal segment orange below and face with black medial stripe is shared only with D. venustus. Differs from that species by: smaller size; distinctive rectangular black bars on sternite 2 reaching side margin; female abdomen and frons more shiny, hind femur and hind tibia paler and yellow bars on abdomen straight and less constricted, not resembling commas. Looks darker in the field than D. venustus. OCCURRENCE. Poorly known as yet owing to confusion with D. venustus until recently, but widespread in the Netherlands and

Belgium near Scots pine forests, and frequent in the pinewoods of Scotland, but with widely scattered records over the rest of Great Britain. ECOLOGY Pine forests. Collected several times on broom. COMMENT Described in 2013. Although probably a valid species, the holotype of D. venustus is purported to be a D. neovenustus, in which case neovenustus should be called venustus, and venustus would need a new name. As this is not yet officially published, we maintain the current arrangement to avoid further confusion. See also comment for D. venustus.

Yellow-faced Brusheye Dasysyrphus hilaris IDENTIFICATION 10–12 mm. A Dasysyrphus with abdominal bars reaching side margin. Face yellow or at most with faint brown tinge around facial tubercle; mouth edge black; third antennal segment orange below; eyes with hairs. Tergites 3 and 4 with little-constricted, quite straight spots reaching side margin; sternite 2 entirely yellow or sometimes with very small spot. SIMILAR SPECIES Like D. venustus, D. friuliensis and D. neovenustus with yellow bars on abdomen reaching side margin, but face without clear black medial stripe. In the quartet, most similar to D. venustus, but besides yellow face, a bit larger, sternite 2 yellow or almost so, and spots on abdomen less constricted; intermediates occur with a faint dark medial stripe on face, or facial tubercle is faintly black. With current knowledge it is unclear whether these specimens are D. hilaris or venustus; this group is in great need of revision, see comment for D. venustus. OCCURRENCE Not well known because of confusion with other Dasysyrphus species, rather scarce but can locally be the dominant Dasysyrphus type. ECOLOGY Damp broad-leaved forests with

well-developed undergrowth; seems to prefer moister habitats than D. venustus. Often visits flowers of buttercup. Larval biology unknown. COMMENT According to recent unpublished genetic research, D. hilaris is a valid species; however, current characters might not always be useful for identification. Pending publication of this research, we retain the current species concept for D. hilaris. See also comment for D. venustus.

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♂

a b d o me n

spo ts do no t re a ch si de m a rgi n

bl a ck cro ssba nd ant enna

hind tarsus

f i rst ta rso m e re s pa l e

♂

3 r d a nten na l seg m ent pa l e b el o w

u n d e rsi d e a b d o me n

♀

♂

a b d o me n

spo ts do no t re a ch si de m a rgi n

o va l spo t

ant enna

l a rg e d ust spo ts

♂

a l l bl a ck

♀

head

u n d e rsi d e a b d o me n

♀

a b d o me n

♂ spo ts do no t re a ch si de m a rgi n

♂

bl a ck cro ssba nd

head

sma l l dust spo ts a n ten na b l a ck

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Lesser Brusheye Dasysyrphus pauxillus IDENTIFICATION 6–8 mm. Small dark Dasysyrphus with pairs

of bars on abdomen not reaching side margin. Face with black medial stripe; hairs on face mainly black; third antennal segment pale below; eyes with hairs. Basal two tarsomeres of hind tarsus pale. Tergites 3 and 4 with pairs of oblique yellow bars not reaching side margin; markings on tergites 3 and 4 only a little constricted, tip of inner side not broadened; sternite 2 with dark rectangular crossband reaching side margin. Male: face wide, eyes meeting at clearly obtuse angle; scutellum largely covered with yellow hairs; sides of tergite 2 mostly covered with black hairs. Female: scutellum with yellow hairs; abdomen conspicuously shiny; dust spots on frons small and indistinct; spots on tergite 2 reach side margin. SIMILAR SPECIES Like D. pinastri and D. lenensis owing to markings on tergites 3 and 4 not reaching side margin; differs from both by having: these markings less constricted and on inner tip less broadened, third antennal segment pale below, mainly yellow hairs on most of scutellum, paler basal tarsomeres

of hind leg and female having small indistinct dust spots on frons. OCCURRENCE Previously and to some extent still confused with D. nigricornis, a northern species. An early Dasysyrphus, with its peak before that of D. pinastri. ECOLOGY Confined to pine forests, often near heathland. Visits flowers of various trees and bushes, often on willow catkins. Males hover 2–3 metres above the ground in pine forests. Larva undescribed. COMMENT This species has been described from the western US, and chances are slim that we have the same species here, so in the future the scientific name in our region might change.

Black-spotted Brusheye Dasysyrphus pinastri IDENTIFICATION 7–11 mm. A medium-sized Dasysyrphus with

pairs of yellow bars on abdomen not reaching side margin. Face with black medial stripe; hairs on face partly pale; antennae black; eyes with hairs. Scutellum covered entirely or largely with black hairs. Hind tarsus black. Tergites 3 and 4 with yellow, oblique, pairs of distinctly constricted bars not reaching side margin; sternite 2 with oval to rounded-triangular black mark not reaching side margin. Male: eyes meeting at a sharp angle; sides of tergite 2 with yellow hairs except posterior corners. Female: dust spots on frons large, merged to a band. SIMILAR SPECIES Combination of black third antennal segment and yellow markings on tergites 3 and 4 not reaching side margin distinguishes it from all Dasysyrphus except D. lenensis. On average, larger than D. lenensis, spot on sternite 2 not reaching side margin (but somewhat variable), spots on tergites 3 and 4 less constricted (especially in male) and female with, on average, larger and often merged dust spots on frons. OCCURRENCE Somewhat later on the wing than D. lenensis. ECOLOGY Mixed and coniferous forests, both pine and spruce.

Often found on yellow flowers. Larva preys on aphids on coniferous trees.

Lena’s Brusheye Dasysyrphus lenensis IDENTIFICATION 8–10 mm. A quite small Dasysyrphus with pairs

of constricted yellow bars on abdomen not reaching side margin. Face with black medial stripe; antennae black; eyes with hairs. Scutellum covered largely or entirely with black hairs. Hind tarsus entirely dark. Tergites 3 and 4 with pairs of oblique bars not reaching side margin, spots distinctly constricted and inner tip broadened; sternite 2 with distinct black crossband reaching side margin (can be difficult to see on dead specimens). Male: sides of tergite 2 with yellow hairs except posterior corners. Female: frons with distinct dust spots that are not connected; markings on tergite 2 not reaching side margin. SIMILAR SPECIES Combination of black third antennal segment and yellow spots on tergites 3 and 4 not reaching side margin distinguishes it from all Dasysyrphus except D. pinastri; for differences, see that species. OCCURRENCE The first Dasysyrphus to appear in spring in spruce forests, a bit earlier than D. pinastri. Locally in spruce plantations of the Belgian high Ardennes, by far the commonest Dasysyrphus. Not known from Great Britain. ECOLOGY Old spruce forests or

mixed forests with old spruces. Larval biology unknown, but likely feeds on spruce-associated aphids.

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a b d o me n

♂

♂

face

halt ere

f a ce ye l l o w

kno b yel l ow

♀

a b d o me n

♂ te rgi te 5 w i th pa i r o f spo ts

♂

face

halt ere

kn o b b l a ck

f a ci a l tube rcl e a nd m o uth e dge bl a ck

♀

♂

a b d o me n

te rgi te 5 bl a ck

♂

face

m a rk i ngs fl uo re sce nt gre e n halt ere

k no b b l a ck

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Pale-knobbed Lucent Didea fasciata IDENTIFICATION 10–13 mm. A black and yellow hoverfly with distinctive abdominal markings evocative of ski goggles. Face yellow, at most dark at facial tubercle; mouth edge yellow; eyes with sparse hairs. Sides of scutellum largely yellow, only black at base. Wing: vein R4+5 with a dip into cell r4+5; stalk of haltere dark, but knob yellow. Abdomen wide and flattened; tergites 3 and 4 with wide yellow bands (sometimes interrupted in middle) with posterior margin sharply constricted in middle, markings resemble ski goggles; tergite 5 black in male, in female with yellow band or pair of spots. SIMILAR SPECIES Easily recognised as a Didea by combination of typical markings on abdomen and dip in vein R4+5. Yellow knob of haltere is most important character and distinguishes it from the other two Didea species. Other distinctive characters are yellow face, on average larger markings on abdomen and pale sides of scutellum. OCCURRENCE Widespread and frequent; our commonest Didea. ECOLOGY Mainly near broadleaved forest but also in conifer woodland. Along paths, forest

glades and forest edges, and in urban parks and gardens. Restless, flies often and fast. Visits flowers, including those of white umbellifers, flowering bushes, Devil’s-bit scabious and Common ivy. Has a long flight period but often most evident late in season. Males rest on leaves or in the vicinity of flowers, from which they chase other insects. Larva feeds on aphids.

Dark-knobbed Lucent Didea intermedia IDENTIFICATION 7–12 mm. A relatively small Didea with yellow

markings on abdomen. Face yellow with black medial stripe from above facial tubercle down to anterior part of mouth edge; eyes with sparse hairs. Scutum with yellow hairs; scutellum with white hairs, only posterior margin with black hairs; sides of scutellum black, posterior margin usually too. Wing: vein R4+5 with a dip into cell r4+5; cell bm bare at base (without microtrichia); haltere entirely brown–black. Abdomen broad and flattened; tergites 3 and 4 with wide yellow bands with posterior margin sharply constricted in middle, markings resemble ski goggles; tergite 5 in male black or with small faint yellow spots, in female with yellow band or pair of spots; sternites dusted. Male: frons entirely yellow; spots on tergite 4 fused to a band, reaching anterior tergite margin. SIMILAR SPECIES Differs from D. fasciata by dark haltere knob, and by dark medial stripe on face, dark sides and posterior margin of scutellum and narrower bands on abdomen. Similar to D. alneti, but smaller and lacks green colour on abdomen (living specimens only); furthermore, scutum with yellow hairs, sternites dusted, cell bm bare at base and female usually

with yellow markings on tergite 5. OCCURRENCE Widespread in areas where pines grow, but always in low numbers. ECOLOGY In pine forest, mixed forests including pine and pine-invaded heathland, often on sandy, base-poor soil. Visits mainly yellow composites, Common heather and rowan. Larva feeds on aphids on pines.

Green Lucent Didea alneti IDENTIFICATION 11–16 mm. A spectacular hoverfly with fluorescent green abdominal markings. Face yellow with black medial stripe from facial tubercle down to anterior part of mouth edge; eyes with sparse hairs. Scutum with yellow hairs, with a narrow band of black hairs between wing bases; scutellum with black hairs, only anterior margin with white hairs; sides and posterior margin of scutellum black. Wing: vein R4+5 with a dip into cell r4+5; cell bm entirely covered with microtrichia; haltere all black. In living specimens, spots on abdomen very distinctive, fluorescent green, in dead specimens colour may change to yellow; tergite 4 with pair of spots, tergite 5 black; sternites without dust spots. Male: frons with black spots above lunule; spots on tergite 4 not reaching anterior margin. SIMILAR SPECIES Living specimens are instantly recognisable by fluorescent green markings on abdomen. In dead specimens, markings fade to yellow, then rendering it like other Didea, but differs from D. fasciata by having black haltere and from D. intermedia by its larger size, less extensive markings on

abdomen, scutum partly covered with black hair, sternites without dust spots and cell bm entirely covered with microtrichia. OCCURRENCE On the continent, widespread near coniferous woodland but always in low numbers and not often repeatedly found at same location. In Great Britain, ephemeral populations have established at several locations, possibly founded by vagrants. ECOLOGY Both pine and spruce forests. Possibly an arboreal species. Males hover 3–4 metres above the ground near trees. Visits, amongst others, maple, white umbellifers, Common heather and yellow composites. Larva preys on aphids and is found on both coniferous and broad-leaved trees.

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a b d o me n

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v e i n R 4+ 5 w i th a di p i nto ce l l r 4+ 5

bl a ck ba nds

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u n d e rsi d e a b d o me n

sc u te l l u m

♂

a nte ri o r m a rgi n bl a ck

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a b d o me n

♀

a b d o me n

te rgi te 4 a nd 5 w hi te -ha i re d

sc u te l l u m a nte ri o r m a rgi n ye l l o w

♂

te rgi te 4 a nd 5 bl a ck -ha i re d

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Great Banded Gossammer Megasyrphus erraticus IDENTIFICATION 10–15 mm. Large, robust hoverfly with a conspicuous zebra pattern when seen from below; often remains in flight when visiting flowers. Face with black medial stripe; antennae black; eyes with hairs. Scutum dark and shiny. Wing: vein R4+5 with a dip into cell r4+5. Tergites 3 and 4 with narrow, fairly straight bands with an incision, sometimes interrupted, in middle, bands placed at or almost at anterior tergite edge, reaching side margin; stripes on tergite 2 straight; sternites with wide black crossbands, alternating with white–yellow bands, creating distinctive zebra pattern. SIMILAR SPECIES Looks like a big, dark Syrphus. Differs from all similar species by vein R4+5 with a dip into cell r4+5. Other distinctive characters are large size, behaviour, face with black medial stripe and dark overall appearance due to dark scutum and only narrow yellow bands on abdomen. OCCURRENCE Widespread but always in low numbers. ECOLOGY Mainly coniferous and mixed forests. Along forest tracks and in forest glades. Males hover 3–5 metres above the

ground, mainly near hill-tops. Visits wide array of flowers, often while hovering in front of the flower. Larva preys on aphids on coniferous trees. COMMENT Confusingly, this species is sometimes placed in the genus Eriozona and was also known under the species epithet annulipes.

Blotch-winged Whitebelt Leucozona lucorum IDENTIFICATION 10–12 mm. Medium-sized fly, part of a small group with distinctive black and white abdomen. Face white with black medial stripe. Scutum brownish; scutellum yellowish with black anterior corners and sometimes narrow black anterior margin. Wing: with distinctive brown–black spot in middle. Tergite 2 and anterior margin of tergite 3 predominantly white–yellow (grey in some males), remainder of abdomen black; hairs on tergite 3 predominantly black, but on tergite 4 white, sometimes hairs in centre dark, but always white at sides, creating a stark colour contrast between black hairs on tergite 3 and white hairs on at least sides of tergite 4. Female: with large connected dust spots on frons. SIMILAR SPECIES Like Epistrophe leiophthalma but eyes with hairs, wing with distinctive marking and abdomen partly covered with black hairs. Very similar to L. inopinata, but scutellum with darker anterior corners, tergite 4 mainly covered with white hairs and scutum browner. OCCURRENCE Though still widespread and locally common over most of North-west Europe, numbers have sharply decreased recently in northern Belgium. ECOLOGY Moist forests with lush undergrowth. Settles on leaves

or flies low through undergrowth vegetation. Regularly visits flowers, including those of Garlic mustard, Greater stitchwort, dandelions and white umbellifers, often in partial shade. Larva feeds on aphids.

Black-haired Whitebelt Leucozona inopinata IDENTIFICATION 10–12 mm. Medium-sized species of a group with a distinctive black and white abdomen. Face white with black medial stripe. Scutum usually with olive dusting; scutellum entirely yellow. Wing: with distinctive brown–black spot in middle. Tergite 2 and anterior margin tergite 3 predominantly white– yellow, remainder of abdomen black. Hairs on tergites 3 and 4 entirely black. Female: frons with large connected dust spots. SIMILAR SPECIES Like Epistrophe leiophthalma but eyes with hairs, wing with distinctive marking and abdomen with darker hairs. Very similar to L. lucorum; for differences, see that species. OCCURRENCE Distribution in Europe still poorly known because of confusion with L. lucorum. Locally in the east of Belgium and the Netherlands but much rarer than L. lucorum. Not known from Great Britain. ECOLOGY Wet forests with rich undergrowth, forest glades. Flies low in herb-rich places, often in partial shade, and visits flowers such as those of Garlic mustard, geraniums and white umbellifers. Larval biology unknown, possibly similar to that of L. lucorum. Unlike L. lucorum, has small second generation in summer. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 1 4 5

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a b d o me n

fore ta rsus bl a ck

ba se scute l l um bl a ck

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a b d o me n

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a b d o me n

♂

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head

f a ce ye l l o w

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Pale-saddled Hoary Leucozona glaucia IDENTIFICATION 11–13 mm. Fairly large fly with pairs of white–yellow or grey–blue spots on abdomen. Face entirely white–yellow; eyes with hairs. Scutum dull green; scutellum yellow, contrasting with darker scutum. Wing: transparent and entirely covered with microtrichia. Fore tibia and fore tarsus yellow. Abdomen with large pair of pale spots on tergite 2, often fused into a band; tergites 3 and 4 with pair of pale narrow spots, colour varying from white–yellow to blue–grey. Female: frons with large dust spots that are narrowly separated in middle. SIMILAR SPECIES Similar to L. laternaria given corresponding abdominal markings and transparent wing, but more robust, scutellum yellow, scutum greener, and fore tibia and fore tarsus yellow. Abdominal markings strikingly similar to those of Epistrophe leiophthalma but differs from that species by eyes having hairs, metasternum bare and wing entirely covered with microtrichia. OCCURRENCE Sharply declining in North-west Europe, has disappeared from northern Belgium and the Netherlands,

and recently also from the east of Great Britain. ECOLOGY Moist forests, tall grassland along forest edges, near streams. Visits tall white umbellifers, usually hogweed and angelica, especially in semi-shaded areas. Larva undescribed, but often found on hogweed; feeds on aphids.

Dark-saddled Hoary Leucozona laternaria IDENTIFICATION 9–11 mm. Slenderer and darker version of

L. glaucia. Face entirely white–yellow; eyes with hairs. Scutum black with blue–green shine; scutellum entirely black or only posterior margin yellow. Wing: transparent. Fore tibia partly and fore tarsus entirely black. Tergite 2 with large pair of spots, tergites 3 and 4 with narrow pair of spots. Female: frons with strips of grey dusting along eyes and a wide dark undusted midline. SIMILAR SPECIES Like L. glaucia but smaller, slenderer, scutellum and scutum darker, spots on tergite 2 not fused to a band, and fore tibia and fore tarsus darker. OCCURRENCE Though initially having a wider distribution than L. glaucia, has sharply declined in North-west Europe to the point that it has also disappeared from northern Belgium and the Netherlands. In Great Britain the decline is, as yet, less pronounced. ECOLOGY Moist broad-leaved forests with rich undergrowth. Along streams, forest paths. Visits white umbellifers, often hogweed and angelica, especially that in semi-shaded areas. Larva feeds on aphids.

Bear Fly Eriozona syrphoides IDENTIFICATION 13–15 mm. A large and restless bumblebee

mimic with a yellow face. Face not protruding. Scutum with black hairs, except for band of pale hairs anteriorly and narrow band posteriorly; scutellum white–yellow, with white hairs. Wing: with dark markings at base and in middle; vein R4+5 without a dip into cell r4+5. Base of abdomen with white hairs, tip with white or orange hairs, black hairs between; ground colour of posterior margin of tergites 4 and 5 orange. SIMILAR SPECIES The only species of the tribe Syrphini covered in this book mimicking a bumblebee. Can be confused with several other bumblebee mimics, but yellow face unique. Like Eristalis oestracea but face yellow and vein R4+5 without a dip into cell r4+5; like a large Cheilosia illustrata, but face yellow and scutellum white–yellow; like Volucella bombylans, but face yellow and not protruding, sides of scutum not yellow and tergite 5 not black. OCCURRENCE A widespread but scarce species in areas with large spruce plantations. ECOLOGY Spruce forests, but a mobile species that wanders widely outside preferred habitat and is able

to colonise small isolated habitat patches. Visits flowers in forest edge, often blossoms in spring, umbellifers and mauve flowers, often hovering in front of flower. Flight quick and alert. Males hover several metres above the ground. Larva feeds on aphids on spruce.

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a b d o me n

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v e rte x shi ny

ant enna

a ri sta bl a ck

♂

♀

head

♀

head

a b d o me n

♂

v e rte x f i ne l y duste d ant enna

a ri sta ora n ge

♂

♀

head

♀

head

a b d o me n

♂

f ro ns a bo v e a nte nna e bl a ck

ant enna

b l a ck

♂

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head

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Dark-backed Smoothtail Epistrophe nitidicollis IDENTIFICATION 9–12 mm. An orange Syrphus-like hoverfly. Third antennal segment pale below; arista black, sometimes brownish at base. Scutum shiny; at least a third of scutellum with black hairs. Wing: at least basal fifth of cell bm bare. Legs entirely yellow, only in male, very base of femora black. Male: frons black, but lunule and area directly above it yellow; frons with dense grey or sometimes more golden dusting along eye margin and with less densely dusted area between, where black ground colour shows through; posterior margin of bands on tergites 4 and 5 usually with incision in middle; pair of spots on tergite 2 small, widely separated in middle. Female: frons black, but lower part, above lunule, yellow, sometimes with narrow black stripe in middle; frons with dust spots along eye margin, spots sometimes almost meeting, but always some shiny parts before, between or behind dust spots; vertex always undusted, shiny. SIMILAR SPECIES Differs from Syrphus by shiny scutum, pale legs, more orange bands on abdomen and upper surface of lower

calypter bare. Differs from other Epistrophe species except E. olgae by combination of partly pale third antennal segment and black hairs on scutellum. Rarely, scutellum almost completely covered with yellow hairs or sometimes hairs missing; these individuals much like E. melanostoma, but cell bm with bare spot at base and frons above lunule yellow. For differences with very similar E. olgae, see that species. OCCURRENCE Confused with E. olgae until recently, but clearly the commonest and most widespread of the pair. ECOLOGY Various types of broad-leaved forest, open landscapes with scattered trees, parks and gardens. Flies low through vegetation and typically visits flowers of sycamore, Field maple and Spindle blossoms, roses and white umbellifers. Larva feeds on arboreal aphids.

Olga’s Smoothtail Epistrophe olgae IDENTIFICATION 9–12 mm. A lookalike of E. nitidicollis. Third

antennal segment orange below; at least basal half of arista orange. Scutum shiny, but thinly dusted; at least a third of scutellum with black hairs. Wing: cell bm with bare spot at base. Legs entirely yellow, only in male very base of femora black. Abdomen with orange, undulating bands. Male: frons above lunule yellow, remainder black, although usually black markings medially reaching lunule; frons with fairly even, usually golden, dusting; spots on tergite 2 relatively large, narrowly separated in middle; posterior margin of bands on tergites 4 and 5 usually only little constricted. Female: lower part of frons above lunule yellow, remainder black, black markings extending downwards to lunule, often in shape of a protruding black trident; frons with large, dense dust spots along eyes, surrounded by finer but distinct dusting covering rest of frons; vertex with fine but clear dusting; bands on tergites 3–5 along posterior margin with small triangular projection in middle. SIMILAR SPECIES For differences with species other than E. nitidicollis, see that species. Much like E. nitidicollis, but arista with orange base and frons more

extensively black, reaching lunule; moreover, male with more even and golden dusting on frons, larger spots on tergite 2 that approach each other and usually less constricted posterior margins of bands on abdomen, female with entirely dusted frons and vertex. Apart from arista colour and dusting, characters variable and overlapping so use them with care. Old individuals with wornoff dusting may be difficult to identify. OCCURRENCE Recently described from Russian Far East, but apparently present throughout most of Europe as well. Distribution as yet poorly known, but widespread in Belgium and the Netherlands, and locally common. Not known from Great Britain. ECOLOGY Mainly damp broad-leaved (alluvial) forests, almost exclusively in forests with Bird cherry, where it can be abundant. Behaviour much like that of E. nitidicollis. The apparent link with Bird cherry may be through its larvae feeding on aphids in this tree.

Black-horned Smoothtail Epistrophe grossulariae IDENTIFICATION 12–16 mm. A large and solid-looking Epistrophe

with wide orange–yellow bands on abdomen. Frons partly covered with black hairs; mouth edge yellow; third antennal segment black. Scutum dull green, anteriorly with two longitudinal stripes of white dusting; scutellum with yellow hairs, but posterior margin with black hairs; metasternum with hairs. Only very base of fore and mid femora black. Tergite 2 with large spots; yellow bands on tergites 3 and 4 wide, posterior margin almost straight, widening towards side margin. Male: frons with dense, yellowish dusting, except above lunule where black spot present; lunule black. Female: frons dark, with grey band of dusting along eyes, leaving a wide dark medial stripe from vertex down to lunule; tergite 5 with black band. SIMILAR SPECIES Looks like bulky, rather cylindrical Syrphus, but bands on abdomen straighter, antennae black and upper surface of lower calypter bare. In Epistrophe, only E. diaphana has also third antennal segment black, but E. grossulariae has frons black above lunule, femora base black and straighter posterior margin of yellow bands on tergites 3

and 4. OCCURRENCE Widespread, periodically numerous outside the traditional habitats possibly because of migrations, although such events have become rare. ECOLOGY Woodland rides and clearings, flower-rich tall grassland, semi-open forested river valleys. Very mobile and sometimes wanders (migrates?) deep into other habitats such as gardens and parks. Males hover several metres above the ground. Visits flowers of, for example, white umbellifers and thistles. Often hovers in front of or above flowers during foraging. Larva feeds on aphids on, for example, sycamore.

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a b d o me n

f ro ns a bo v e a nte nna e ye l l o w

ant enna

a nten na b l a ck

♂

♀

head

♀

head

a b d o me n

♂ ba nds na rro w

wing hyaline

f ro ns bl a ck

ta rso m e re 1 da rk

♀

ant enna

♂

head f ro ns bl a ck

f ace

a ri sta yel l ow

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head

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a b d o me n

♂ ba nds na rro w

wing darke ne d

f ro ns bl a ck

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head

black ri n g ta rso m e re 1 pa l e r f ro ns bl a ck

ant enna

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a ri sta bl a ck

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Pale-sided Smoothtail Epistrophe diaphana IDENTIFICATION 10–13 mm. Fairly small Epistrophe with wide

pale-yellow bands on abdomen and a conspicuously whitish face. Frons yellow–white, with yellow hairs and white dusting; vertex black; third antennal segment black, contrasting against whitish frons. Scutum dull; scutellum with yellow hairs; metasternum with hairs. All femora yellow. Tergites 3 and 4 with wide yellow bands, posterior margin constricted in middle and just before side margin. Female: tergite 5 yellow. SIMILAR SPECIES Owing to black third antennal segment, mainly to be confused with E. grossulariae; easily separated from it by entirely yellow–white frons without black mark above lunule, entirely yellow femora and posterior margin of yellow bands on tergites 3 and 4 with deeper incision. The rather pale tone and great extent of yellow on abdomen is a useful field clue. OCCURRENCE Has recently expanded northwards in Great Britain, Belgium and the Netherlands. ECOLOGY Usually found in umbellifer-rich tall grassland and field margins, also woodland rides or clearings. Males hover at a height of 2–3 metres

above the ground in sheltered sunny spots. Mainly visits white umbellifers. Larva preys on aphids, possibly on hogweed.

Wavy-banded Smoothtail Epistrophe cryptica IDENTIFICATION 11–14 mm. A restless large and dark Epistrophe.

Face relatively wide; genae and sides of lower part of face with yellow hairs; clypeus wide. Frons entirely black continuing down from vertex to adjacent to lunule; largely dusted below vertex, without or with very small undusted zone above lunule, if present, much shorter than length of third antennal segment. Lunule black; third antennal segment partly or entirely orange; at least base of arista yellow. Scutum shiny; scutellum with yellow hairs. Wing: cell bm entirely covered with microtrichia. Hind tibia usually with narrow diffuse black ring in middle in male, usually absent in female; at most, a third of hind femur tip along anterior side with black hairs; anterior side of hind tibia with a mix of black and yellow hairs; tarsomere 1 of hind tarsus mainly or entirely black. Tergites 3 and 4 with narrow undulating orange bands; tergite 5 with black band occupying at least three-quarters of tergite width. Male: at least basal half of hind femur black; eyes meeting at an angle of almost 100°. Female: pair of spots on tergite 2 narrow; mouth edge usually yellow. SIMILAR SPECIES For differences with other Epistrophe except E. obscuripes, see that species. Very similar

to E. obscuripes, easiest difference to discern is this species’ yellow arista; moreover, face wider (resulting in larger angle at which eyes meet in male), wing less dark, hind femur and hind tibia with more black hairs, genae and sides of lower part of face with fewer black hairs and tarsomere 1 of hind tarsus darker. OCCURRENCE In North-west Europe mainly in low mountain ranges, but recently also occasionally in lowland broad-leaved forests in Belgium and the Netherlands, possibly expanding. Not known from Great Britain. ECOLOGY Broad-leaved and mixed forests, often areas with a moderately high proportion of hawthorn, often hovering in front of flowers while feeding. Often visits flowering hawthorn. Larva feeds on aphids.

Dark Smoothtail Epistrophe obscuripes IDENTIFICATION 11–14 mm. A restless, dark Epistrophe with

narrow bands on abdomen. Face narrow; genae and usually also sides of lower part of face with numerous black hairs; clypeus wide; frons black, continuing downwards to adjacent to lunule, lunule itself also black; undusted zone above lunule roughly equals length of third antennal segment; third antennal segment mainly pale; arista black. Scutum shiny; scutellum with yellow hairs. Wing: anterior margin brownish; cell bm entirely covered with microtrichia. Anterior side of hind femur mainly or entirely covered with yellow hairs; anterior side of hind tibia with yellow hairs; upper side of tarsomere 1 of hind tarsus yellow or only apical part dark; hind tibia usually with narrow diffuse black ring in middle in male, usually absent in female. Tergites 3 and 4 with narrow orange bands; tergite 5 with black band occupying at least three-quarters of tergite width. Male: at least basal half of hind femur black; eyes meeting at an angle of c. 92°. Female: pair of spots on tergite 2 narrow; mouth edge usually largely black. SIMILAR SPECIES Differs from other Epistrophe species

except E. cryptica by combination of entirely black frons down to adjacent to lunule, extensive black markings on tergite 5, hind tibia sometimes with faint black ring, pale third antennal segment and yellow hairs on scutellum. Very similar to E. cryptica; for differences, see that species. OCCURRENCE In North-west Europe, locally in low mountain ranges. Not known from Great Britain. ECOLOGY Broad-leaved and mixed forests, often areas with a good share of hawthorn. Males hover 1–2 metres above the ground in forest glades. Mainly visits hawthorn, but also white umbellifers, often hovering in front of flowers while feeding. Larval biology unknown.

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two dus te d whitis h s tripe s

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tars us dark ce l l bm w i th ba re spo t a t ba se hi nd ma rgi n wi th n o tch

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cl ype us w i de

u n d e rsi d e h e a d

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m o uth e dge bl a ck , o ra l ca v i ty w i de

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undulating hind ma rgi n

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ce ll bm e ntire ly cove red with microtrichia

f ro ns na rro w ye l l o w -ha i re d fa ce n o t wi de sc u te l l u m

wing detail

u n d e rsi d e h e a d

cl ype us na rro w

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bl a ck a nte ri o r m a rgi n V -sha pe d

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fa ce very wi de

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Yellow-mouthed Smoothtail Epistrophe flava IDENTIFICATION 11–14 mm. A fairly large Epistrophe with broad

orange bands on abdomen. Third antennal segment partly or entirely orange; lower part of frons yellow; clypeus wide; mouth edge yellow. Scutum dull, anteriorly with two longitudinal stripes of white dusting; scutellum with yellow hairs. Hind tibia yellow; hind tarsus dark. Tergite 4 characteristic: posterior margin of orange band fairly straight but with small clear notch in middle; tergite 5 orange or with small black mark. Male: wing cell bm entirely covered with microtrichia. Female: frons entirely dusted except above lunule; wing cell bm usually with bare spot at base; spots on tergite 2 very large, with typical trapezoid shape and widely connected with side margin and anterior margin of tergite. SIMILAR SPECIES Most often confused with E. melanostoma, but distinguished by dull scutum, yellow mouth edge and posterior margin of orange band on tergite 4 with central notch, whereas E. melanostoma has posterior margin constricted in middle, but without notch, and band convex towards side margin; in female,

spots on tergite 2 larger, and widely reaching anterior margin of tergite, but in E. melanostoma spots of different trapezoid shape and reaching anterior margin only in upper corner. The two longitudinal stripes on scutum are quite distinctive, but can occur to some extent in other Epistrophe species, so not a reliable character. OCCURRENCE A widespread but local and rather rare species in mainland North-west Europe; often confused with other Epistrophe. ECOLOGY In and near large, old mature broad-leaved forests. Flies quite high, males hover often 2–5 metres above the ground, at forest edges, etc. Visits flowers of many plants. Larva preys on aphids.

Black-mouthed Smoothtail Epistrophe melanostoma IDENTIFICATION 8–12 mm. A typical Epistrophe with broad orange bands. Third antennal segment partly or entirely orange; mouth edge partly or entirely black; clypeus wide and mainly dusted; oral cavity wide, distance between oral cavity and eyes small; face relatively narrow. Scutum shiny; scutellum with yellow hairs. Wing: cell bm entirely covered with microtrichia. At least apical two-fifths of anterior side of hind femur with black hairs; hind tibia yellow. Tergites 3 and 4 with broad orange bands; tergite 5 orange or with small triangular black mark in centre. Male: eyes meeting at a right angle; frons directly above lunule with black mark, remainder of frons dark yellow, latter sometimes difficult to judge owing to thick dark-grey–yellow dusting; hind femur entirely yellow or base black for at most two-fifths. Female: about lower quarter of frons yellow, upper three-quarters black, but black extension in centre reaches lunule; at least upper two-thirds of frons dusted; anterior and upper side of hind tibia with black hairs; spots on tergite 2 wide, reaching side margin but not anterior tergite margin. SIMILAR SPECIES Can be confused with several other Epistrophe. For differences with E. flava and E. ochrostoma, see those

species. Like E. cryptica and E. obscuripes, but distinguished by having lower part frons yellow, anterior side of hind femur more extensively covered with black hairs, hind tibia yellow and orange bands on abdomen wider. Like E. nitidicollis but scutellum with yellow hairs, if hairs absent or worn, check cell bm, as it is entirely covered with microtrichia in this species and frons above lunule more extensively black. OCCURRENCE A common species in Belgium and the Netherlands in broad-leaved woodlands; first seen in Great Britain in 1986 but increasing. ECOLOGY Broadleaved forests, often with sycamore, with rich undergrowth. Typically visits flowers of sycamore, Field maple and Spindle blossoms, and tall umbellifers. Larva feeds on aphids.

Broad-faced Smoothtail Epistrophe ochrostoma IDENTIFICATION 8–12 mm. An Epistrophe with orange bands on tergites 3 and 4, and a remarkably wide face. Third antennal segment partly or entirely orange; face very wide, shiny for at least two-thirds of width; clypeus very narrow and entirely shiny; oral cavity narrow, distance between oral cavity and eyes large; frons above lunule yellow. Scutum shiny; scutellum with yellow hairs. Wing: cell bm entirely covered with microtrichia. Hind tibia yellow. Male: eyes meeting at a very wide angle, c. 107°; dust on frons whitish. Female: frons with unique pattern – upper part black with V-shaped anterior margin, lower part yellow; dust spots not meeting. SIMILAR SPECIES Differs from all other Epistrophe except E. melanostoma by combination of pale third antennal segment, yellow hairs on scutellum, frons yellow above and next to lunule, and cell bm entirely covered with microtrichia. Wide face is distinctive, but use the following other characters too to distinguish it from otherwise very similar E. melanostoma: clypeus much narrower, a reliable character, but difficult to assess in the field; oral cavity narrower, frons above lunule yellow, shiny central

part of face wider; in male, eyes meet at a larger angle. Best field character for females is unique pattern on frons: a V-shaped sharp division between black upper part and yellow underpart. OCCURRENCE The earliest of the orange-banded Epistrophe. Shows remarkable population fluctuations: often hardly seen for several years and then suddenly pervasive. ECOLOGY Broadleaved and mixed forests. Most often seen on willow catkins and Blackthorn blossoms. Larval biology unknown.

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na rro w ye l l o w ba nd

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a b d o me n

sm a l l spo ts

♀ obli q ue sp o ts

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sm a l l yel l ow spo ts

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Spring Smoothtail Epistrophe eligans IDENTIFICATION 10–12 mm. A dark Epistrophe with reduced

orange markings on abdomen. Eyes bare; third antennal segment pale below; frons above lunule black. Scutum shiny copper– green; scutellum with yellow hairs. Hind femur with yellow hairs. Abdomen with large spots on tergite 2, tergite 3 with a narrow band, remainder of abdomen black; sometimes tergite 4 with narrow yellow band (variation trifasciata); bands on tergites 3 and 4 sometimes interrupted in middle; spots on tergite 2 large and rectangular in female, smaller and more triangular in male. SIMILAR SPECIES Typical individuals are easily identified by characteristic abdominal markings in which tergite 4 is black or has reduced yellow markings. Could be mistaken for an Eristalis species, but wing vein R4+5 not sinuous and less bulky. Variation trifasciata can have quite wide bands on tergites 3 and 4, and can be confused with other Epistrophe and may key out to E. obscuripes owing to combination of partly pale third antennal segment, yellow hairs on scutellum, shiny scutum and hind femur

with yellow hairs; however, frons lateral to lunule yellow and pair of spots on tergite 2 triangular in male and rectangular in female instead of more bar-shaped in E. obscuripes. OCCURRENCE A very common and widespread Epistrophe, possibly increasing. The phenology of this species is changing in response to climate change and in south-east England it is not uncommon to record males in late March. ECOLOGY Broad-leaved forests, grassland with trees and scrubs, parks and gardens, occasionally well away from trees. Males hover 2–4 metres above the ground in small groups on more-or-less sheltered open places such as forest tracks, forest edges and gardens. Visits flowers, often found on flowering bushes. Larva feeds on arboreal aphids on trees and scrubs.

Whitebelt Smoothtail Epistrophe leiophthalma IDENTIFICATION 11–14 mm. An odd-looking Epistrophe that

resembles a species of Leucozona. Face yellow, mouth edge black; third antennal segment black; eyes bare. Metasternum with hairs; scutellum yellow and with yellow hairs. Wing: base of cell bm bare (without microtrichia). Tergite 2 with whitish dusted wide spots on anterior half; tergites 3 and 4 anteriorly with pairs of whitish dusted spots, those on tergite 3 sometimes fused to a band. SIMILAR SPECIES Very different from other Epistrophe species, but resembling Leucozona glaucia; differs from L. glaucia by being larger and more robust, eyes bare, metasternum with hairs and base of cell bm bare. OCCURRENCE A species of Central European high mountain ranges; a vagrant in North-west Europe. Not known from Great Britain. ECOLOGY Alpine flower-rich tallgrassland meadows. Near streams in forest glades. Larva feeds on aphids. COMMENT Similar to Leucozona species, and formerly placed in that genus, but shape of male genitalia and morphology of larva indicates it is Epistrophe.

Gold-spotted Smoothtail Epistrophella euchroma IDENTIFICATION 8–10 mm. Distinctive medium-sized species with orange spots on abdomen. Third antennal segment orange; face yellow; eyes bare. Legs entirely yellow in female, in male base of femora black, remainder of legs yellow. Abdomen elongated with obliquely-set pairs of fairly wide orange rectangular spots on tergites 3 and 4 not reaching side margin; characteristic very small spots at side margin at junctions between tergites 2–4 easily overlooked. Female: frons extensively black with small triangular dust spots. SIMILAR SPECIES Small spots alongside margin at junctions between tergites 2–4 are diagnostic. Otherwise, like Meliscaeva auricollis, but spots are more rectangular and legs paler; like Meligramma triangulifera but spots on tergites 3 and 4 not reaching side margin and legs paler. In female, black frons with only small lateral dust spots combined with pattern and colours on abdomen distinguishes it from all similar species. OCCURRENCE Rather scarce in Great Britain but widespread and locally common in nearby mainland Europe. ECOLOGY In and around broad-leaved woodland, also hedgerows and in parks

with Spindle, hawthorn and other flowering bushes. Males hover on hill-tops or along forest edges and forest glades. Settles on sunlit leaves and visits white umbellifers, Field maple, Spindle and hawthorn. Larva feeds on aphids, presumably associated with bushes or trees. COMMENT Taxonomic position not entirely clear yet, sometimes placed in the genus Meligramma or Epistrophe.

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a b d o me n

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sl i ghtl y co nv e x

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ve in R 4 + 5 with a dip into ce ll r 4 + 5

head

a ngl e >150°

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head

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a b d o me n

spo ts re a ch si de m a rgi n

f l a t o r sl i ghtl y co nca v e

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a ngl e a p prox. 100°

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White-bowed Smoothwing Scaeva pyrastri IDENTIFICATION 10–15 mm. A large and easily recognised species with white spots on abdomen. Eyes with hairs. Frons swollen, especially distinctive in male. Scutum shiny; sides of scutum yellow–white. Wing: vein R4+5 with a dip into cell r4+5. Underside of fore femur with at least a few black hairs. Abdomen in living specimens with pairs of bright white, golf club-like, obliquely-set spots on tergites 3 and 4; in pinned specimens, white markings on abdomen often turn yellow; sternites with wide rectangular black marks. Female: abdomen sometimes entirely black, variation unicolor; this variation is smaller and at certain angles markings remain vaguely visible as bands of white hairs. SIMILAR SPECIES Easily recognised by combination of large size and colour and shape of markings on abdomen. Differs from Dasysyrphus species by vein R4+5 with a dip into cell r4+5. S. albomaculata also has pairs of obliquely-set spots on abdomen, but in that species spots are yellow, wider and less constricted, sides of scutum are brighter yellow–white, markings

on sternites narrower and fore femur entirely covered with white hairs. Spots on tergites 3 and 4 in S. selenitica yellow and not oblique. OCCURRENCE Widespread. Apart from being a migrant in variable numbers, abundance strongly depends on the presence of aphids, which is highly affected by climatic events such as droughts. ECOLOGY Mainly in open habitats, to some extent anthropophilic – cropland, parks, gardens etc., but much less common in forests. Good numbers may be seen on hogweed, thistles, bramble and other plants. Larva feeds on aphids on assorted low-growing plants and scrubs.

Yellow-bowed Smoothwing Scaeva selenitica IDENTIFICATION 12–15 mm. A large Scaeva with yellow markings on abdomen. Eyes with hairs. Frons swollen, especially distinctive in male. Wing: vein R4+5 with a dip into cell r4+5. Tergites 2–4 with pairs of yellow spots, spots on tergite 3 parallel with posterior margin of tergite, usually not reaching side margin; black spots on sternites small. Male: frons strongly swollen, so eyes meeting at a very obtuse angle, over 150°. Female: frons in profile slightly convex; face with several black hairs; most hairs on eyes longer than posterior ocelli; face wide, vertex widely rectangular. SIMILAR SPECIES Spots on abdomen are reminiscent of Dasysyrphus and Eupeodes species. Differs from Dasysyrphus by larger size and vein R4+5 with a dip into cell r4+5. Differs from Eupeodes by having hairs on eyes, bare metasternum and vein R4+5 with a dip into cell r4+5. Like a large L. lapponicus, eye hairs in S. selenitica are easiest way to identify it; moreover, wing mostly without microtrichia, male with eyes meeting at a larger angle and female with more extensively dusted frons in S. selenitica. Distinguished from S. pyrastri by spots on abdomen being yellow and not oblique. For differences with very similar

S. dignota, see that species. OCCURRENCE Widespread and relatively frequent, but scarce in the British Isles. Can show migratory behaviour in summer. ECOLOGY Coniferous forest is the favourite habitat, but can be seen in almost any habitat: parks, gardens, forest glades, forest tracks. Males hover 2–4 metres above the ground. Visits various types of flowers. Larva feeds on aphids, mostly on pines and spruce, but possibly also on broadleaved trees or bushes.

Southern Smoothwing Scaeva dignota IDENTIFICATION 11–14 mm. Slightly smaller lookalike of much commoner S. selenitica. Eyes with hairs; frons moderately swollen. Wing: vein R4+5 with a dip into cell r4+5. Tergites 2–4 with pairs of yellow spots; spots on tergite 3 parallel with posterior margin of tergite; spots on tergites 3 and 4 reach side margin; black spots on sternites narrow. Male: frons moderately swollen; eyes meeting at an angle of 90–106°. Female: frons in profile flat or slightly concave; face with pale hairs only; vertex seen from above narrowly rectangular, almost square; spots on abdomen rather wide. SIMILAR SPECIES For differences with species other than S. selenitica, see that species. Very similar to S. selenitica but males easily identified by less swollen face, causing eyes to meet at a much smaller angle. Identifying females much more difficult; use as many of the following characters as possible, although not all characters always work: frons in profile slightly concave instead of clearly concave (an overrated character, difference often very subtle or negligible), face covered entirely with pale hairs, hairs on eyes shorter, vertex narrower, pairs of spots on tergites 3

and 4 usually wider and reaching side margin of tergites (which also regularly occurs in S. selenitica). Some females best left unidentified. OCCURRENCE Has become a frequent (yearly) and increasing vagrant since 2000 in North-west Europe. Is able to reproduce there but probably has not yet established permanent populations. ECOLOGY Often in urban areas, gardens, open dry flower-rich grasslands; attracted to colourful conspicuous flowers, or glasses with soft drinks. Larva feeds on aphids.

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a b d o me n

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si de m a rgi n bl a ck

ve in R 4 + 5 with a dip into ce ll r 4+ 5

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u n d e rsi d e a b d o me n

head frons swol l en

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a b d o me n

frons swol l en ba se w i ng ba re

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Large-spotted Smoothwing Scaeva albomaculata IDENTIFICATION 10–15 mm. A Scaeva with pairs of large oblique spots on abdomen. Eyes with hairs; frons swollen, especially distinctive in male. Scutum shiny, sides brightly yellow or whitish. Wing: vein R4+5 with a dip into cell r4+5. Underside of fore femur entirely covered with yellow hairs. Tergites 3 and 4 with pairs of oblique pale-yellow spots, spots being relatively wide and hardly constricted; sternites with wide rectangular black markings. Male: eyes meeting at a very obtuse angle. Female: frons completely yellow below black vertex. SIMILAR SPECIES Eupeodes lookalike because of shape of spots, but identified in the field by combination of large size, shiny scutum with yellow–white sides, wing with vein R4+5 with a dip and wide, oblique abdominal spots. Male also by obtuse angle between eyes and female by largely yellow frons. Differs from S. pyrastri by having wider and less constricted spots on tergites 3 and 4, fore femur covered entirely with yellow hairs and sides of scutum yellow–white. OCCURRENCE In Europe, restricted to the Mediterranean Basin,

but vagrants have turned up in Great Britain twice. ECOLOGY In southern Europe, found in open habitats with low flowers. Larva feeds on aphids. COMMENT Scaeva mecogramma is known from one Scottish record, from over a century ago. Easily distinguished from other Scaeva in having narrow undulating bands rather than pairs of spots on tergites 3 and 4. In this book, it would key out to Megasyrphus erraticus but compared to that species frons largely yellow instead of entirely black, abdomen more elongated, bands on abdomen undulating instead of almost straight and metasternum bare.

Bow-veined Aphideater Lapposyrphus lapponicus IDENTIFICATION 9–12 mm. Resembling a Eupeodes species

or a small Scaeva. Eyes bare. Scutellum with black hairs; metasternum bare. Wing: base of alula without microtrichia, sometimes only narrowly so in male; vein R4+5 with a dip into cell r4+5. Abdomen with pairs of rather small yellow spots; side margin of tergite 5 black; sternites with oval to rectangular spots that often point forwards in middle. SIMILAR SPECIES Much like a Eupeodes, but differs by vein R4+5 having a dip into cell r4+5 and metasternum bare; if these characters are missed, keys out to E. nielseni. Could be mistaken for a Scaeva owing to bare metasternum and dip in vein R4+5, but smaller, eyes bare and wing extensively covered with microtrichia. OCCURRENCE Shows migratory behaviour, usually in June, when it can be common near forests and appear in various places. Females sometimes overwinter. ECOLOGY Mixed and coniferous forests, mainly spruce, but can appear everywhere as a migrant. Males frequently hover in groups above forest tracks 2–5 metres above the ground. Visits various flowers. Larva feeds on aphids. COMMENT Until recently, mainly known under the name

Eupeodes lapponicus, but genetic and morphological differences suggest it is better to place this species in a separate genus.

Smooth-winged Aphideater Eupeodes lundbecki IDENTIFICATION 11–12 mm. A large Eupeodes that looks like a

Scaeva. Eyes bare; frons swollen, especially in male. Scutellum partly covered with black hairs. Wing: about basal half bare; base of alula bare; vein R4+5 without a dip into cell r4+5. Tergites with pairs of yellow spots; sternites 2–4 with oval black spots. Male: eyes with sharp division between much larger facets on upper part of eye and smaller facets on lower part; eyes meeting at obtuse angle, c. 120°. Female: frons in profile slightly swollen. SIMILAR SPECIES Amongst Eupeodes species, readily identified because large part of wing without microtrichia and frons swollen, creating in male an obtuse angle at which eyes meet, in female frons convex in side view, although sometimes subtle. At first glance, like Scaeva selenitica, owing to swollen frons and similar abdominal markings, but eyes bare, vein R4+5 without a dip into cell r4+5 and metasternum with hairs. OCCURRENCE In area covered by book, a very rare late-summer migrant. Becomes more common from Denmark toward the north and north-east. ECOLOGY As a vagrant often appears in places with abundant

flowers. Flies low above herbs, but also higher, near bushes and trees. Larval biology unknown.

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undul a ti ng a nte ri o r m a rgi n

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ge ni ta l i a l a rge

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u n d e rsi d e a b d o me n

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u n d e rsi d e a b d o me n

a b d o me n

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ge ni ta l i a sm a l l

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a nteri o r m a rg i n stra i ght head e nti re l y co v e re d w i th m i cro tri chi a

frons wi tho ut dust spo ts

alula

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a b d o me n

undul a ti ng ba nds

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♂ e ntire ly cove re d wi th microtrichia

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u n d e rsi d e a b d o me n

w i de ba nds

alula

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Migrant Aphideater Eupeodes corollae IDENTIFICATION 7–10 mm. A fairly small, common Eupeodes mostly seen in open areas. Scutellum with yellow hairs, at most with a few black hairs. Wing: alula bare at base. Abdominal markings variable in male, pairs of yellow spots on tergites 3 and 4 wide or (occasionally) narrow; if wide, spots often connected in middle in male; yellow markings often reduced in winter and spring, more extensive in summer; side margin of tergite 5 entirely yellow; sternites 2–4 with rounded spots not reaching side margin. Male: genitalia conspicuously large, readily assessable in the field, reaching posterior margin of sternite 4, therefore centre of sternite 5 constricted to anterior margin. Female: vertex and, at most, upper third of frons black, below yellow, division sharp and straight, at most middle with a very short black protrusion; frons with dust spots along eye margin; tergite markings less variable than in male, the yellow much paler (creamy-yellow) and with spots of tergites 3 and 4 well separated. SIMILAR SPECIES The large genitalia in the male

distinguishes it from all other Eupeodes species. Most resembles E. latifasciatus owing to small size and yellow hairs on scutellum, but alula bare at base. In addition to larger genitalia, male with undulating anterior margin of yellow markings on tergite 3 and female with spots instead of bands on tergites 3 and 4 and frons with dust spots. OCCURRENCE A very common species, numbers are strongly affected by migrants during summer. Increasingly seen during winter months, these individuals are very dark with small oblique spots. ECOLOGY Mainly in open and/or disturbed areas with low-growing vegetation: dunes, agricultural land, parks and gardens, brownfield land, urban areas up to city centres. Much lower numbers in forests. Visits flowers of many plants. Larva feeds on aphids on low herbs.

Broad-banded Aphideater Eupeodes latifasciatus IDENTIFICATION 7–10 mm. A small Eupeodes. Scutellum with

yellow hairs. Wing: alula entirely covered with microtrichia. Anterior margin of bands on tergites 3 and 4 close to anterior tergite margin and almost straight, except with shallow incision in middle, rarely dividing band into spots; sternites with rounded rectangular black spots, spot on sternite 4 can be very small or absent. Male: occiput quite wide up to top, narrowest part about two-thirds of maximum width; bands on tergites 3 and 4 not reaching side margin or only in anterior corner; genitalia not conspicuously large. Female: frons black above, yellow below, division sharp, black margin slightly undulating; frons entirely shiny, without dust spots; bands on tergites 3 and 4 reach side margin. SIMILAR SPECIES Male identified from other Eupeodes species by combination of yellow hairs on scutellum, small genitalia and almost straight anterior margin of yellow markings on tergites 3 and 4. Females always easily identified by undusted frons with sharp division between shiny black upper part and yellow lower part. OCCURRENCE A very widespread and relatively common species. ECOLOGY Open areas, marshes, grasslands,

agricultural areas, but also gardens and forest edges. Mainly visits low flowers. Larva feeds on aphids on low plants.

Wavy-banded Aphideater Eupeodes nitens IDENTIFICATION 10–11 mm. Medium-sized Eupeodes. Scutellum

largely covered with black hairs. Wing: over half of cell bm covered with microtrichia; alula entirely covered with microtrichia. Tergites 3 and 4 with narrow, undulating bands, rarely narrowly interrupted in middle; black spots on sternites 3 and 4 very large, wide, rectangular and reaching side margin or almost so, often with anterior corners extended towards anterior margin. Long hairs at posterior side of fore femur base mostly black. Male: occiput in side view narrow near vertex, less than a third of maximum width; eyes meeting at an acute angle; side margin of tergite 5 black. Female: frons black above, yellow below, with a black V-shaped marking extending downwards between dust spots; face narrow; bands on tergites 3 and 4 reaching side margin; tergite 5 with large black spot, usually reaching tergite side margin, side margin usually partly black; sternite 5 with black band; hind femur entirely yellow or only very base black; about half of cell bm covered with microtrichia. SIMILAR SPECIES In male, combination of alula entirely

covered with microtrichia and side margin of tergite 5 black diagnostic, distinguishing it from all other Eupeodes. Female is like E. bucculatus and E. goeldlini, but spots on sternites wider, reaching side margin, long hairs at posterior side of fore femur base mostly black and alula always entirely covered with microtrichia (usually not in E. bucculatus). OCCURRENCE Relatively widespread, usually scarce, but locally more common. ECOLOGY Forest tracks and glades in old broad-leaved and mixed forests on base-poor soil, heaths. Heathy rides and clearings on sandy base-poor soils in Great Britain. Visits low flowers such as those of yellow composites, Common tormentil and white umbellifers.

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a b d o me n

♂ si de m a rgi n ye l l o w

o va l spo ts

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f ace

fa ce wi d e alula

ba se b a re

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u n d e rsi d e a b d o me n

b l a ck Y -sha pe d m a rk i ng

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head

♀

a b d o me n

♂ si de m a rgi n bl a ck

l a rge re cta ngul a r spo ts

alula

b a se b a re

♂

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head

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Lunuled Aphideater Eupeodes luniger IDENTIFICATION 10–12 mm. A common and relatively large

Eupeodes. Scutellum largely covered with black hairs. Wing: alula with bare spot at base. Tergites 3 and 4 with pairs of yellow spots rarely narrowly connected, but never reaching side margin; side margin of tergite 5 yellow, at most anterior corner black; sternites 3 and 4 with oval spots not reaching side margin, very dark individuals in spring sometimes with large rectangular spots with rounded corners. Long hairs on posterior side of fore femur at least mostly yellow. Male: eyes meeting at sharp angle, on average 80°; over half of cell bm bare. Female: frons black above, yellow below, in middle with a black Y-shaped marking extending between dust spots; face about 1.1–1.5 times wider than an eye. SIMILAR SPECIES Can be very similar to E. nielseni, especially in early spring; for differences, see that species. Rarely, E. luniger has bands instead of spots on tergites 3 and 4, making it similar to, for example, E. nitens, but bands less narrow and undulating than in that species, and alula with bare spot at base and long hairs on posterior side of fore femur pale. Most similar to E. bucculatus and E. goeldlini; useful field feature is the pair of spots on tergites 3 and 4, in E. luniger sometimes narrowly fused to bands, but never the undulating narrow bands seen in E. bucculatus and E. goeldlini; furthermore, alula usually entirely covered with microtrichia in those two (but often not so in female E. bucculatus), E. bucculatus has on average larger, wider and more rectangular black markings on sternites, and face of E. luniger is usually wider than in the other two species. OCCURRENCE A very widespread and very common species, with a very long flight period. ECOLOGY Common in both natural and

agricultural or urban areas: forests, grasslands, parks or gardens. Males hover alongside bushes and forest edges up to several metres above the ground. Visits many different flowers including the first spring-blossoming scrubs. Larva feeds on aphids on lowgrowing plants.

Pinewood Aphideater Eupeodes nielseni IDENTIFICATION 9–11 mm. A dark Eupeodes with pairs of small spots on abdomen. Scutellum mostly covered with black hairs. Wing: alula at base with narrow strip bare of microtrichia. Base of posterior side of fore femur largely or entirely covered with black hairs. Pairs of spots on tergites 3 and 4 rarely connected to form a band; side margin of tergite 5 largely or entirely black; sternites 3 and 4 with large rectangular spots, spot on sternite 4 not much smaller than spot on sternite 3. Male: eyes meeting at an angle greater than 90°, frons slightly swollen; occiput narrow near vertex, less than a third of maximum width; less than half of cell bm covered with microtrichia. Female: frons extensively black, black marking anteriorly with notch, lower part of frons yellow, dust spots quite small, narrow and pointed inwards, leaving a wide V-shaped black marking in middle; base of hind femur extensively black, often for two-thirds its length. SIMILAR SPECIES Lapposyrphus lapponicus has sides of tergite 5 black as well, but has vein R4+5 with a dip into cell r4+5 and metasternum bare. Very often confused with dark individuals of other Eupeodes species, the real nielseni usually being a rare species! Biggest challenge is distinguishing it from dark E. luniger (usually in early spring), especially since E. luniger can, exceptionally, have side margin of tergite 5 dirty black and sternites with large and rectangular black spots; males best recognised by eyes meeting at an obtuse angle to produce a much broader frons (angle sharper and frons narrower in E. luniger) and narrower occiput near vertex; moreover, male E. nielseni with black, rather than dark, tergite 5, more dark hairs on anterior side of fore femur base, wider and more rectangular spots on sternites, whereas in female frons more extensively black and with smaller dust spots, creating V-shaped instead of Y-shaped black marking

between. Because not every character works well, identification can be very difficult and a reference collection is of great help. Like E. nitens but alula narrowly bare at base and tergites 3 and 4 with paired spots, only seldomly with a band. E. bucculatus can have base of alula bare too, but face narrower in that species, abdomen almost always with bands and side margin of tergite 5 yellow, but see comment 2 at E. goeldlini. OCCURRENCE A rare and often misidentified species in North-west Europe, somewhat more common in low mountain ranges and especially the Larch zone in the Central European high mountains. ECOLOGY In the vicinity of coniferous forests, probably mainly near Scots pine and Larch. Has been observed visiting white blossoms and a variety of low flowers. Larva feeds on aphids on coniferous trees.

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a b d o me n

undul a ti ng ba nds

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head

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u n d e rsi d e a b d o me n

u n d e rsi d e a b d o me n

f ace

fa ce na rro w

re cta ngul a r spo ts

e ntire ly cove re d with m i crotri chi a , in ♀ with narrow bare stri p

ce l l bm 5 0 % co v e re d w i th m i cro tri chi a

e ntire ly cove re d with mi cro tri chi a wing detail

alula

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Narrow-banded Aphideater Eupeodes bucculatus IDENTIFICATION 9–12 mm. A typical Eupeodes with yellow bands

on abdomen. Face narrow; scutellum largely covered with black hairs. Long hairs on posterior side of fore femur entirely or at least mostly yellow. Tergites 3 and 4 with fairly narrow undulating yellow bands often not reaching side margin, seldom with pairs of spots (usually in spring); side margin of tergite 5 yellow, at most anterior corner black. Male: eyes meeting at a right angle or less; alula almost always entirely covered with microtrichia; about half of cell bm bare; black spot on at least sternite 3 (often 4 as well) wide rectangular, in anterior corners sometimes pointed. Female: frons with a black Y-shaped marking extending into yellow area, frons with wide dust spots; face narrow, approximately 0.8– 1.1 times width of an eye; base of alula usually with small bare area; only tip of cell bm with microtrichia; sternites 3 and 4 with wide rectangular spots with rounded corners; sternite 5 yellow or with black spot in middle, sometimes also with two small black side spots. SIMILAR SPECIES Like E. luniger but abdomen with narrow undulating bands and sternites with large rectangular spots; alula in male almost entirely covered with microtrichia; female with bare spot but often with traces of microtrichia at alula base (large magnification required), face narrower in female. Female much like E. nitens, but alula usually with small bare spot and legs with black base. For more differences between these species, see their descriptions. Very similar to E. goeldlini, but abdominal bands narrower and of more uniform width (like in E. nitens), whereas in E. goeldlini bands more like convex pairs of spots that are medially narrowly connected; black markings on sternites more extensive, always somewhat rectangular,

in E. goeldlini spots smaller and more oval; E. goeldlini has alula nearly always entirely covered with microtrichia, female E. bucculatus usually has a bare spot at base; cell bm more extensively bare in E. bucculatus. OCCURRENCE Distribution still insufficiently known because of confusion with E. goeldlini (and other Eupeodes). Probably widespread in North-west Europe but in low numbers. ECOLOGY On average, drier habitats: well-drained broad-leaved forest, heathlands, gardens, but to some extent also in many other habitats. Visits low flowers, such as yellow composites. Larval biology unknown.

Goeldlin’s Aphideater Eupeodes goeldlini IDENTIFICATION 9–12 mm. A lookalike of E. bucculatus. Scutellum

largely covered with black hairs. Wing: alula entirely covered with microtrichia. Long hairs on posterior side of fore femur at least mostly yellow. Tergites 3 and 4 usually with undulating bands, sometimes with pairs of convex spots; side margin on tergite 5 yellow, at most anterior corner black. Male: eyes meeting at a right angle or less; cell bm covered with microtrichia for 50–85%; black spots on sternites rounded. Female: upper part of frons black, lower part yellow, with a black Y-shaped marking extending downwards between fairly large dust spots; base of all femora black; sternites 3 and 4 with rounded black spots; sternite 5 yellow, often with two small side spots, sometimes with a black spot between side spots. SIMILAR SPECIES For differences with very similar E. bucculatus, see that species. For differences with E. luniger, E. nitens and E. nielseni, see those species. OCCURRENCE Due to confusion with similar species, the distribution is still poorly known, but a relatively widespread species in Belgium and the Netherlands; generally in low densities. ECOLOGY Moist broad-leaved forests, alder and willow carr, along rivers and small streams. Visits flowers of, for example, yellow composites and willow. Larval biology unknown. COMMENTS 1) E. bucculatus and E. goeldlini are known for their large variation in markings on abdomen, and according to the original description they are morphologically indistinguishable (except by their male genitalia); however, we believe that at least in the area covered by this book they can be distinguished by some constant characters detailed above. 2) Some important characters to distinguish Eupeodes are clearly more variable than is generally assumed. For example, the extent of microtrichia cover on the alula, the colour of hairs in the femora, or the colour of the margin of tergite 5

can vary widely, which is often sex dependent. Some individuals show a mix of characters of different species and thus best remain unidentified.

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a b d o me n

a b d o me n

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a m o unt o f yel l o w va ri a bl e

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clos e d wing s horter than abdome n

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toothed lobes

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g e n i ta l i a d o rsa l vi e w

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proj ecti on

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Common Globetail Sphaerophoria scripta IDENTIFICATION 7–12 mm. A large Sphaerophoria. Scutum with

continuous bright-yellow sides, although less distinct behind transverse suture. Male: abdomen very elongated, extending well beyond wing-tips; markings on abdomen variable, ranging from wide yellow bands to narrow yellow bands or pairs of spots; genitalia: toothed lobe very wide, without projections; hairy lobe over 1.5 times higher than wide (see lower photo on page 12 for explanation of lobes). Female: cell bm covered with microtrichia for, at most, 40%; hind femur with wide bare strip on inner side, surrounded by one or several bristly hairs. SIMILAR SPECIES Male: one of the few Sphaerophoria that can be easily identified in the field, being unique in having abdomen extending well beyond closed wing; genitalia also characteristic, the only Sphaerophoria with very wide toothed lobe, without projections. Female identified with difficulty, usually impossible from photographs: cell bm covered with microtrichia for, at most, 40%, versus at least 50% in the other species; for more characters, see key. OCCURRENCE Widespread and common in open habitats. Strongly migratory, so prone to appear everywhere. ECOLOGY Mainly open habitats: dunes, cropland, meadows, grasslands and gardens. Visits all sorts of herbs and low flowers. Larva preys on aphids on herbs.

Broad-banded Globetail Sphaerophoria taeniata IDENTIFICATION 8–10 mm. A fairly large Sphaerophoria. Scutum

with continuous bright-yellow sides, although less distinct behind transverse suture. Male: abdomen quite long, extending just beyond wing-tips and with relatively wide yellow bands, rarely with paired spots; side margin of tergite 3 with yellow hairs; genitalia: hairy lobes about as long as wide; toothed lobes narrow, with two processes at tip; inner side of surstylus, between hairy and toothed lobes, with a projection, sometimes fairly indistinct. Female: cell bm covered with microtrichia for 60–80%; abdomen distinctly wide in centre; tergites 3 and 4 with fairly wide, barely constricted, yellow bands; black band on posterior part of tergite 5 on either side of central stripe even; sternites 5 and 6 without longitudinal fold; side margin of tergites 3 and 4 largely covered with black hairs. SIMILAR SPECIES Male: abdomen can be quite long, but still not as long as in S. scripta; when in doubt, check genitalia. Shares having narrow toothed lobes with two processes at tip with S. batava and S. fatarum, but differs from former by having projection on inner side of surstylus (sometimes indistinct) and side margin of tergite 3 having yellow hairs, and from latter by yellow band instead of paired spots on tergite 2 and less shouldered toothed lobe. Female: diagnosis is provisional, robust specimens with straight yellow bands on tergites are recognisable, but certain identification remains difficult, see attempt in key. OCCURRENCE Widespread in the range covered by this book, but most frequent in southern England (where populations have massively increased), Belgium and the Netherlands. Has sharply declined after the recent droughts in northern Belgium. ECOLOGY A variety of open, permanent grassy situations. Visits small low flowers, including those of buttercup. Larva probably feeds on aphids. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 1 6 7

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g e n i ta l i a d o rsa l vi e w

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ab d o m e n

two p rocesses

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toothed lobes

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g e n i ta l i a d o rsa l vi e w

ha i ry l o be s hi ghe r tha n w i de

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g e n i ta l i a ve n tra l vi e w

ab d o men n a rro w yel l ow b a nds

♂

toothed lobes

♂

g e n i ta l i a ve n tra l vi e w

f i nge r-l i ke pro ce ss

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Pinewood Globetail Sphaerophoria batava IDENTIFICATION 7–10 mm. Small Sphaerophoria with wide yellow

bands on abdomen. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: side margin of tergite 3 with black hairs; genitalia: hairy lobes about as long as wide; toothed lobes narrow with two (usually blunt) processes at tip; inner side of surstylus, between hairy and toothed lobes, without a projection. Female: cell bm covered with microtrichia for c. 60%; tergites 3 and 4 with yellow bands; black band along posterior margin of tergite 5 with a distinct extension anteriorly on either side of medial stripe; sternites 5 and 6 without longitudinal fold; side margin of tergites 3 and 4 mainly or entirely covered with black hairs. SIMILAR SPECIES Male: identification possible only by checking genitalia; shares combination of abdomen with bands and narrow toothed lobes with two processes at tip with S. taeniata, but inner side of surstylus without projection (although rarely a slight bulge) and hairs on side margin of tergite 3 black; like S. fatarum but abdomen with bands instead of paired spots, inner side of surstylus without projection and toothed lobe less shouldered. Female: diagnosis is provisional, see key, but it is not certain whether the given characters always work. OCCURRENCE Widespread but local, can be common along heathlands, scarce in other habitats. ECOLOGY Forest glades and woodland rides in dry forest (often pine forest) on base-poor soil, heathlands. Flies low through vegetation and visits low flowers, often of Common tormentil. Larval biology unknown but larva probably feeds on aphids.

Black-footed Globetail Sphaerophoria philanthus IDENTIFICATION 7–8 mm. A fairly small and dark Sphaerophoria.

Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: tergites with relatively narrow yellow bands, sometimes reduced to pairs of spots; genitalia: hairy lobes c. 1.5 times higher than wide; toothed lobes symmetrical, usually black, very wide, at tip with narrow finger-like process in centre and at inner side with less distinctive triangular process; inner process arrow-shaped. Female: cell bm covered with microtrichia for c. 60%; tergites 3 and 4 with yellow bands or with paired spots; black band along posterior margin of tergite 5 with a distinct extension anteriorly on either side of medial stripe; sternites 5 and 6 without longitudinal fold; at least anterior part of side margin of tergites 3 and 4 with pale hairs. SIMILAR SPECIES Males can be identified only by checking genitalia: combination of short abdomen and hairy lobes 1.5 times higher than wide is unique in the area covered by this book, visible by looking at underside of abdomen. When collected, also identified by characteristic toothed lobe, it being very wide with small finger-like process at tip. Females so far cannot be identified with certainty, but see key for indicative characters. OCCURRENCE Widespread in Great Britain, more localised on the continent. Locally common in suitable habitat. ECOLOGY Heathlands, mires, edges of moorland, poor shortcropped unimproved base-poor grasslands (frequently alongside S. fatarum), also in dune slacks. Flies low and visits low flowers such as of Common tormentil. Larval biology unknown, but probably feeds on aphids.

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to o th e d l o b e s

i nne r pro ce ss na rro w a nd po i nte d

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f i nge r-l i ke pro ce ss

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g e n i ta l i a vi e we d f ro m a b o ve

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abdomen

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genitalia dorsal view

sho rt spi ne s

♂

to o th e d l o b e s

pro j e cti o n

♂ tw o pro ce sse s

spo ts

♀

abdomen

♂

♂ genitalia ventral view

g e n i ta l i a d o rsa l vi e w

♂

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to o th e d l o b e s

l a rge f i nge r-l i ke pro ce ss

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Heath Globetail Sphaerophoria virgata IDENTIFICATION 8–10 mm. A Sphaerophoria in which male has wide yellow bands on abdomen. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: side margin of tergite 3 with black hairs; genitalia: hairy lobes about as long as wide; toothed lobes symmetrical, very wide and tip with narrow finger-like process at upper corner, on inner side before tip with a very short process that continues down as a transverse bulge densely covered with short spines; inner process narrow and pointed. Female: black band along posterior margin of tergite 5 with a distinct extension anteriorly on either side of medial stripe; sternites 5 and 6 without longitudinal fold; sternites extensively covered with black hairs; cell bm covered with microtrichia for c. 80%. SIMILAR SPECIES Male can be identified only by checking genitalia, using this diagnostic combination of characters: toothed lobes wide, symmetrical; apical finger-like process positioned at upper corner, on inner side before tip with a very short process that continues down as a transverse bulge

densely covered with short spines and inner process narrow and pointed. Females may not be identified with certainty, but see key for indicative characters. OCCURRENCE A widespread but generally scarce Sphaerophoria, locally abundant in low mountain moorland and unimproved grassland in eastern Belgium, western Germany and Denmark. ECOLOGY Mainly heathlands and unimproved grassland on base-poor soils, also at the edges of moorland and on open areas in forest on base-poor soil. Prefers drier locations to species such as S. philanthus and S. fatarum. Flies low through vegetation and visits low flowers such as of Common tormentil. Larval biology unknown, but probably feeds on aphids.

Bog Globetail Sphaerophoria fatarum IDENTIFICATION 6–8 mm. A fairly small and dark Sphaerophoria

with spots on abdomen. Scutum with continuous brightyellow sides, although less distinct behind transverse suture. Male: tergites 3 and 4 with pairs of small yellow spots, those on tergites 3 and 4 can be fused to a narrow band (summer generation); genitalia: hairy lobes about as long as wide; toothed lobes with two processes at tip; toothed lobes widening (shouldered) before processes; inner side of surstylus, between hairy and toothed lobes, with a projection, sometimes indistinct. Female: face yellow or with narrow brownish medial stripe; cell bm almost or entirely covered with microtrichia; abdomen short and oval, sternite 3 clearly wider than long; paired yellow spots on tergites 3 and 4 hardly narrowing towards side margin; posterior corners of sternites 3 and 4 usually with a few black hairs only, but sometimes posterior corners of sternite 4 with many black hairs; sternites 5 and 6 normal shape or with longitudinal fold; sternite 5 at middle twice as long as sternite 6. SIMILAR SPECIES Male: shares paired spots or narrow bands on abdomen with S. philanthus, S. interrupta and some S. scripta but genitalia very

different; can be identified only by checking genitalia: shares narrow toothed lobes with two processes at tip with S. batava and S. taeniata but these species have bands instead of paired spots on tergites 3 and 4; moreover, toothed lobes with shoulders more distinct in S. fatarum and in S. batava inner side of surstylus, between hairy and toothed lobes, without a projection. Female: may not be identified with certainty, but see key for indicative characters. OCCURRENCE A widespread but rather scarce species, the spring generation is quite early and may be partly overlooked. ECOLOGY Heathlands, mires, edges of moorland, unimproved boggy grasslands and woodland rides on base-poor soil. Spring generation often visits flowers of grasses and willow catkins, summer generation on Common tormentil and Common heather. Larval biology unknown, but probably feeds on aphids.

Interrupted Globetail Sphaerophoria interrupta IDENTIFICATION 7–10 mm. A fairly large Sphaerophoria with

pairs of large spots on abdomen. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Both male and female with pairs of spots on tergites 2–4. Male: genitalia: hairy lobes about as long as wide; toothed lobes narrow, asymmetrical, with large finger-like process at tip. Female: face with a long wide black or brown medial stripe; wing: cell bm almost or entirely covered with microtrichia; abdomen short and fairly broad, sternite 3 distinctly wider than long; pairs of yellow spots on tergites 3 and 4 quite large and wide, at sides spots narrow towards posterior margin, spots not reaching side margin or only as a very narrow line. SIMILAR SPECIES Male: useful first feature in the field is the abdomen with pairs of spots, almost all other species have bands except S. fatarum and sometimes S. philanthus or S. scripta; genitalia distinctive, the only Sphaerophoria in the region covered by this book in which toothed lobes end as a large finger-like process. Female: identified by pairs of wide spots on abdomen which narrow towards side

margin but normally do not touch it. OCCURRENCE A widespread species in Great Britain, but has declined sharply in parts of continental North-west Europe. ECOLOGY Moist grasslands, along streams or at the edges of moorland. Can be found in lusher and richer vegetation than the other ‘small’ Sphaerophoria. Flies through low or medium–high vegetation. Visits a variety of small flowers. Larva lives on herbs, such as Red campion, preying on aphids.

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to o th e d l o b e s

bro a d ro unde d ti p

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w i de sho ul de rs

e pa ndri um a nd ha i ry l o be s a s l o ng a s w i de

♀

abdomen

♂ genitalia ventral view

♂

g e n i ta l i a d o rsa l vi e w

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to o th e d l o b e s

tw o pro ce sse s

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i nne r pro ce sse s ha i ry l o be s w i de r tha n hi gh

♀

abdomen

♂ genitalia ventral view

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g e n i ta l i a d o rsa l vi e w

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to o th e d l o b e s

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ha i ry l o be s l i ke l o w na rro w ba nd

♂ genitalia ventral view

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Bankowska’s Globetail Sphaerophoria bankowskae IDENTIFICATION 8–10 mm. A rare Sphaerophoria in which the

male has yellow bands on abdomen. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: side margin of tergite 3 with black hairs; genitalia: both epandrium and hairy lobes about as long as wide; toothed lobes symmetrical, with wide shoulders, inner side near tip with a small triangular process and tip with small finger-like process; inner process stalked, with broad rounded tip. Female: cell bm almost or entirely covered with microtrichia; abdomen short and oval, sternite 3 wider than long. SIMILAR SPECIES Male: can be identified only by checking genitalia; shares broad shoulders on toothed lobes with S. fatarum, but that species has paired spots on abdomen instead of bands and inner process narrower. Female: doubtful whether she can be identified with certainty. OCCURRENCE Very rare in North-west Europe. Nearly always caught as singletons. Populations may be very small or ephemeral. Larger numbers can be found in alpine meadows of

high mountains in Central Europe outside the range covered by this book. ECOLOGY Small, damp flower-rich grasslands in forest. Visits various low flowers. Larval biology unknown, but probably feeds on aphids.

Tormentil Globetail Sphaerophoria potentillae IDENTIFICATION 6–7 mm. A small Sphaerophoria in which male

has wide yellow bands on abdomen but those on tergite 4 sometimes reduced to pair of spots. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: side margin of tergite 3 covered mainly or entirely with black hairs; genitalia: hairy lobes short, about half as high as wide, due to short hairy lobes, inner processes visible in hind view, diverging, forming a V; toothed lobes narrow, with two processes at tip; inner side of surstylus, between hairy and toothed lobes, without a projection. Female: face yellow or with narrow brown medial stripe; cell bm almost or entirely covered with microtrichia; abdomen short and oval, sternite 3 clearly wider than long; pairs of yellow spots on tergites 3 and 4 hardly narrowing towards side margin; posterior corners of sternites 3 and 4 with 20–30 black hairs; sternites 5 and 6 normal shape and same width medially. SIMILAR SPECIES Male: can be identified only by checking genitalia, the very short hairy lobes are a useful character. Female: not possible to identify with certainty, but see key for an attempt. OCCURRENCE A North-west European endemic of coastal wet

grasslands and coastal heaths. ECOLOGY Found in wet Culm grasslands, wet heathland and at the edges of moorland in coastal areas. Visits low flowers, including those of Common tormentil. Larval biology unknown, but probably feeds on aphids.

Eastern Globetail Sphaerophoria chongjini IDENTIFICATION 7–10 mm. A Sphaerophoria in which the male has wide yellow bands on abdomen. Scutum with continuous bright-yellow sides, although less distinct behind transverse suture. Male: side margin of tergite 3 with yellow hairs; genitalia: hairy lobes very low, hardly visible, with straight upper margin, making inner processes visible as parallel projections above hairy lobes; toothed lobes angular, ending in a blunt point. Female: tergites 3 and 4 with yellow bands; black band on posterior part of tergite 5 on either side of medial stripe even; sternites 5 and 6 without longitudinal fold; anterior part of side margin of tergites 3 and 4 with pale hairs. SIMILAR SPECIES Male: can be identified only by checking genitalia; strongly reduced hairy lobes are a useful character, and inner processes clearly visible behind them. Female: may look like S. taeniata, but not possible to identify with certainty; possibly S. chongjini has a yellow instead of black frons, but more research is needed. OCCURRENCE A very rare species in the area covered by this book, with only sporadic sightings in some larger woodlands in the south. Not known from Great

Britain. ECOLOGY Open areas and woodland rides in well-drained forest and unimproved dry grassland on base-rich soils. Flies low through vegetation and visits flowers. Larval biology unknown, but probably feeds on aphids.

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♀ ♂

♀

face

a b d o me n

yel l o w si d es i nterru pted

f a ce ye l l o w

♂

ha i ry l o be s l a rge a nd hi gh

head

a n ten na yel l ow

♂

tooth e d l o b e s

♂

g e n i ta l i a d o rsa l vi e w

♂ ♂

yel l ow si d e s sto p a f te r tra n sverse suture

♀ ♂

to o th e d l o b e s

abdome n

♂

g e n i ta l i a ve n tra l vi e w

head ha i ry l o be s a rc-sha pe d

♂

g e n i ta l i a d o rsa l vi e w

an ten na b l a ck

♂

♂

yel l o w si d e s sto p a f te r tra nsverse suture

♀ ♂

a b d o me n

head

♀

to o the d l o be s a l m o st l a ck i ng f ace

antenna yel l ow bl a ck m e di a n stri pe

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♂ g e n i ta l i a ve n tra l vi e w

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Rueppell’s Globetail Sphaerophoria rueppelli IDENTIFICATION 5–8 mm. A small, distinctive Sphaerophoria.

Antennae largely yellow, at most third antennal segment dark at tip; face yellow or at most facial tubercle dark. Scutum with coppery sheen (in living specimens); sides yellow from postpronotum to transverse suture, whereafter black, although postalar callus often slightly yellow; anteriorly usually with pale dusted longitudinal stripes. Markings on abdomen very variable, ranging from pairs of narrow yellow spots to largely yellow abdomen, but even in the latter tergite 2 with pair of widely separated oblique spots. Male: abdomen constricted between tergites 2 and 3; genitalia: toothed lobe a triangular projection; hairy lobes rounded and very high. SIMILAR SPECIES Owing to black posterior half of scutum sides, can be confused only with S. loewi and S. shirchan; largely yellow antennae differentiates it from S. loewi, face without black medial stripe and tergite 2 with pair of widely separated spots distinguishes it from S. shirchan; moreover, genitalia very different from both.

OCCURRENCE Widespread but often impermanent. Rapidly colonises its ephemeral ruderal habitat so must be rather mobile. ECOLOGY All types of frequently disturbed vegetation such as salt marshes, ruderal areas including temporary abandoned cropland, brownfield land, fringes of large rivers or ponds with seasonally variable water level. Flies close to the ground through low open vegetation. Visits small low flowers. Larva can be found on herbs, feeding on aphids.

Saltmarsh Globetail Sphaerophoria loewi IDENTIFICATION 7–9 mm. A rare, orangish Sphaerophoria.

Antennae black; face white–yellow. Scutum with strong coppery sheen (in living specimens); sides yellow from postpronotum to transverse suture, whereafter black, although postalar callus often slightly yellow. Markings on abdomen quite variable. Male: markings on abdomen usually with orange tinge, pale markings on tergite 2 often reduced, giving a dark impression in the field, but sometimes abdomen mostly orange–yellow; genitalia: toothed lobe a very narrow finger-like projection with tooth on upper margin; hairy lobes arc-shaped, not covering full upper side of epandrium. Female: abdomen with pairs of convex yellow–orange spots. SIMILAR SPECIES Owing to black posterior half of sides of scutum, confused only with S. rueppelli and S. shirchan, but its black antennae are characteristic, also genitalia of male very different and female usually with wider and more orange pairs of spots on abdomen. OCCURRENCE A very localised species over its whole range, largely coastal but can also occur more inland. ECOLOGY Broad, not-too-dense fringes of emergent vegetation, with Common reed and Sea clubrush in brackish water of coastal

marsh (the typical habitat in Great Britain) or Common reed and Common bulrush in freshwater marsh. Stays above the water and rarely comes ashore. Males have a surprisingly rapid flight just above the water among thin vegetation of Common reed or rushes and sometimes settle on the vegetation. Visits mainly flowers of plants that grow in or over the water, for example, Fineleaf water dropwort, Cowbane and Common bulrush. Larval biology largely unknown, but probably feeds on aphids.

Stripe-faced Globetail Sphaerophoria shirchan IDENTIFICATION 5–9 mm. A rarely observed and little-known

Sphaerophoria. Face with wide black medial stripe, from antennae up to mouth edge; antennae yellow. Scutum shiny, with yellow sides from postpronotum to transverse suture, whereafter black, although postalar callus often slightly yellow. Male: in addition to typical larger yellow marks on anterior part of abdominal tergites, tergites 3 and 4 often also with a yellow posterior edge, genitalia with toothed lobes almost absent; hairy lobes high and rounded, with black bristly hairs. SIMILAR SPECIES Combination of black posterior part of side of scutum and face with black medial stripe distinguishes it from all other Sphaerophoria in the region covered by this book. Male genitalia highly aberrant owing to almost absent toothed lobes and black bristly hairs on hairy lobes. OCCURRENCE Very rare and local. Possibly a pioneer species, that establishes temporary populations in recent clearcuts or along broad managed forest tracks. Not known from Great Britain. ECOLOGY Recent open areas in forest, after windfall or clearcutting, along forest tracks. Flies low and fast above the

ground between low vegetation. Visits low flowers such as those of Strawberryleaf cinquefoil. Larval biology unknown, but probably feeds on aphids.

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♂ ♀

a b d o me n

co nstri cte d large a nd unmis tak a b l e

♂ ♀

a b d o me n

te rgi te s 3 a nd 4 w i th ba nds

♂

♀

a b d o me n

na rro w spo ts

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Phantom Potterfly Doros profuges IDENTIFICATION 14–16 mm. Large, unmistakable and enigmatic species. Sides of scutum yellow; scutellum red or red–brown. Wing: anterior part dark. Abdomen slender, club-shaped, constricted at tergite 2; tergite 2 with yellow side markings; tergites 3 and 4 with in total three narrow yellow bands. SIMILAR SPECIES Unmistakable by combination of shape, size and colour pattern. Superficially resembles Temnostoma bombylans, but abdomen constricted and scutum with yellow sides. OCCURRENCE A very local and scarce species; has sharply declined. Conspicuous yet elusive, but not clear why. ECOLOGY Along the edges of heathland and chalk grasslands, woodland rides and open forest on well-drained soil. Often sits near bushes and on the leaves of bramble on the transition from open vegetation to forest but can be an open chalk grassland species in parts of England. Visits flowers of bushes and umbellifers, with several sightings from Alder buckthorn. Flight period remarkably short, sometimes seen for only a few days at a location. Larva probably

lives associated with ant nests, possibly Lasius fuliginosus, but otherwise nothing is known about the larval biology.

Crossband Dayglower Xanthogramma laetum IDENTIFICATION 8–10 mm. An atypical Xanthogramma. Eyes

with long hairs in male, with sparse hairs in female; face yellow. Sides of scutum bright yellow. Legs all yellow in female; femora black at base in male. Tergite 2 with pair of spots, tergites 3 and 4 with bands that in some males are interrupted in middle. SIMILAR SPECIES Differs from other Xanthogramma by hairs on eyes, bands instead of spots on tergites 3 and 4 and transparent wing. Differs from Syrphus and allies by scutum having brightyellow ‘sides’. OCCURRENCE Has recently increased in continental North-west Europe. Not known from Great Britain. ECOLOGY A species of large broad-leaved forests, lives in the forest interior. Rarely visits flowers. Favours partial shade and usually flies low and inconspicuously above short vegetation in forest. Males sit on the forest floor in small sunlit open spots. Egg-laying has been observed on moss-covered roots of beech stumps, but larval biology unknown. COMMENT Previously known as Olbiosyrphus laetus, but genetic research shows it belongs to Xanthogramma.

Barred Dayglower Xanthogramma citrofasciatum IDENTIFICATION 10–12 mm. A contrasting, lovely hoverfly. Eyes bare. Sides of scutum bright yellow. Wing: dark along anterior margin. Legs entirely orange–yellow. Abdomen oval; tergites 2–4 with pairs of narrow yellow spots of roughly the same width. SIMILAR SPECIES Superficially resembles Chrysotoxum species, but antennae much shorter. Differs from the trio X. pedissequum, X. dives and X. stackelbergi by having spots on tergite 2 more narrow, legs entirely yellow and wider, and abdomen more oval. Differs from X. laetum by its bare eyes, tergites 3 and 4 with spots instead of bands and wing dark along anterior margin. OCCURRENCE Widespread but localised. An early Xanthogramma species, may be expanding northwards on the continent. ECOLOGY Mainly chalk grasslands and heathlands, and more generally warm well-drained grasslands with mounds of ants. Flies low through grassy vegetation and visits low flowers. Larva lives in ant nests of the genus Lasius; found in nests of L. alienus and L. niger, where it eats aphids tended by the ants. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 1 7 7

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♂

♂

u n d e rsi d e a b d o me n

♀

a b d o me n

♀

a b d o me n

bl a ck

i nner si de spo ts po i nted

♀

head

th o ra x l a te ra l

med i a n stri p e connected wi th vertex

side s o f tho ra x w i th o ne o r tw o ye l l o w spo ts

♂ ♂

u n d e rsi d e a b d o me n

po i nte d ye l l o w

i n ner si de spo ts b l unt

♀

head

th o ra x l a te ra l

m edi a n stri p e no t co nnected wi th vertex

si de s o f tho ra x w i th thre e o r f o ur ye l l o w spo ts

♂ ♂

u n d e rsi d e a b d o me n

♀

a b d o me n

stra i ght o r ro unde d ye l l o w

wing tip darke ne d

♀

head

th o ra x l a te ra l

si de s o f tho ra x w i th thre e o r f o ur ye l l o w spo ts

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Superb Dayglower Xanthogramma pedissequum IDENTIFICATION 10–12 mm. The common summer

Xanthogramma of open grassland. Eyes bare. Sides of scutum bright yellow; sides of thorax with one or two yellow spots, seldom with a faint third one. Wing: dark-brown spot extends quite far below pterostigma; wing-tip transparent or slightly dark. Hind femur and hind tibia with black markings. Yellow pair of spots on tergite 2 roughly an equilateral triangle, clearly wider than spots on tergites 3 and 4; microtrichia on membrane between tergites and sternites 3 and 4 black on posterior half, giving impression that sternite black markings continue in full width on membrane. Male: pair of spots on tergite 2 reaching side margin in full width. Female: black medial stripe on frons posteriorly clearly connected with vertex and anteriorly widening, reaching lunule widely. SIMILAR SPECIES For differences with X. laetum and X. citrofasciatum, see those species. Much like X. stackelbergi and X. dives, but sides of thorax with only one or two, seldom three, but never four bright spots like in the other two. Most reliable

character is the colour of microtrichia on membrane next to sternites 3 and 4: posterior half black in X. pedissequum, all yellow in other two. OCCURRENCE Widespread and often frequent over most of North-west Europe, except in the northern part of Great Britain and the northern part of the Netherlands. ECOLOGY Nottoo-dry, tall grasslands, roadsides, gardens. Males hover low, 0.5–1 metres above the ground, sometimes several together, above grasslands, often near taller vegetation or forest edge. Larva found in nests of Lasius flavus and L. niger, where they eat aphids tended by the ants.

Stackelberg’s Dayglower Xanthogramma stackelbergi IDENTIFICATION 10–12 mm. A lookalike of X. pedissequum

and X. dives. Eyes bare. Sides of scutum bright yellow. Sides of thorax with four bright-yellow spots. Wing: dark-brown spot extends not far below pterostigma; wing-tip transparent. Hind femur and hind tibia with some black markings. Yellow pair of spots on tergite 2 clearly wider than spots on tergites 3 and 4; pair of spots on tergite 2 roughly like an equilateral triangle with blunt inner side, especially in female; microtrichia on membrane between tergites and sternites 3 and 4 yellow. Male: posterior margin of spots on tergite 2 bends inwards before reaching side margin; anterior margin of black band across sternite 2 with a pointed, medial extension. Female: black medial stripe on frons not reaching vertex or only as a narrow line, anteriorly towards lunule its width remains constant or narrows; spots on tergite 2 with wide blunt inner side. SIMILAR SPECIES For differences with X. laetum and X. citrofasciatum, see those species. Much like X. pedissequum and X. dives, for differences with former, see that species. Differs from X. dives by spots on tergite 2 with more blunt inner side and bent inwards before side margin (especially

males), spot under pterostigma narrower and black band across sternite 2 with a pointed, medial extension. OCCURRENCE Has a very different habitat from the very similar X. pedissequum, but distribution not yet well known. ECOLOGY Forests with an open canopy, woodland rides, mostly on base-poor soils. In forest glades or along sunlit forest tracks, often in partial shade. Flies a little later in the season compared to X. pedissequum. Males hover 3–7 metres above the ground between trees at hill-tops. Larva lives in ant nests; egg-laying females have been observed near the entrance of an ant nest of the genus Lasius.

Smoky-winged Dayglower Xanthogramma dives IDENTIFICATION 10–12 mm. A lookalike of X. pedissequum and

X. stackelbergi. Eyes bare. Sides of scutum bright yellow, sides of thorax with four bright-yellow spots. Wing: dark-brown spot extends quite far below pterostigma; wing-tip above vein R4+5 dark, especially in female. Hind femur and hind tibia extensively black. Pair of yellow spots on tergite 2 clearly wider than spots on tergites 3 and 4; those on tergite 2 roughly like an equilateral triangle with pointed inner side and not bent inwards before side margin; microtrichia on membrane between tergites and sternites 3 and 4 yellow; anterior margin of black band across sternite 2 straight or with a low, more or less rounded medial projection. Female: shape of black medial stripe on frons variable. SIMILAR SPECIES For differences with X. laetum and X. citrofasciatum, see those species. Much like X. pedissequum and X. stackelbergi; a dark wing-tip above vein R4+5 and extensively black leg 3 are strong indicators of X. dives. Differs from X. pedissequum by having yellow microtrichia on membrane between tergites and sternites 3 and 4, and more yellow spots

on sides of thorax. For differences with X. stackelbergi, see that species. OCCURRENCE Widespread but with fragmented populations over North-west Europe. Expanding in Belgium and the Netherlands. Not known from Great Britain. ECOLOGY Habitat association still unclear because only recently recognised, but appears linked to rather moist habitats, often a mixture of moist forest and meadows near rivers or ditches. Larval biology unknown, but like other Xanthogramma probably lives in ant nests.

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l o nge r ha i rs

♂ a n te n n a

♀

head

fa ce d uste d e x ce pt fa ci a l tube rcl e

♀

♂

scu tu m

sho rt-ha i re d

♂

an te n n a

♀

♀

te rgite s 2 –4 approx. s quare

head

face

f a ce shi ny

♂

♀

p o stg o n i te s

sl i ghtl y l o nge r tha n w i de

ye l l o w -ha i re d

♂

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scu tu m

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Long-winged Duskyface Melanostoma scalare IDENTIFICATION 7–9 mm. A very slender species with orange– yellow spots on abdomen. Face dusted except facial tubercle, contrasting with dusted face; arista with hairs, hairs erect and at least on basal half about as long as width of arista at base, a subtle character that too often is impossible to judge from photographs or with a hand lens. Metasternum sharply reduced in middle, diamond-shaped. Male: fore leg normal shape; abdomen very long and slender; sternite 2 c. 2.5 times as long as wide at its posterior margin. Female: frons with distinct triangular dust spots along eye margin; pairs of spots on tergites 3 and 4 rounded to hollowed at outer posterior corner, creating a somewhat triangular shape. SIMILAR SPECIES Most reliable character to distinguish this species from all other Melanostoma species are the long hairs on the arista, but this can be assessed only under the microscope; also, face with denser dusting than most, creating larger contrast between dusted face and shiny facial tubercle. In the field, males are best identified by their very long and slender abdomen, sternite 2 c. 2.5 times as long as wide at its posterior margin, instead of at most two times. Male like Platycheirus angustatus, but fore leg normal shape. OCCURRENCE Widespread and common near forest. ECOLOGY Found in various habitats, but compared to M. mellinum nearly always in the vicinity of scrub and woodland, not in large open grassland or moorland. Flies low near bushes and trees and visits flowers. Usually active in partial shade and also active in cold weather. Males hover up to 3 metres above the ground in semi shade. Larva feeds on aphids on grasses and herbs.

Variable Duskyface Melanostoma mellinum IDENTIFICATION 5–8 mm. A familiar hoverfly with orange spots on abdomen. Arista with short adpressed hairs, hairs not longer than half the width of arista at base; face narrow, shiny. Abdomen not conspicuously narrow. Male: eyes meeting at an angle of c. 80–90°; frons shiny; scutum usually entirely covered with pale hairs; anterior part of scutum with short hairs, about one-quarter of scutellum length; metasternum sharply reduced in middle, diamond-shaped; fore leg not modified; abdomen with three pairs of spots; abdomen with black hairs intermixed with pale hairs, especially along midline and close to posterior tergite margin; tergites 2–4 about as long as wide; sternite 2 about as long as wide. Female: frons without or with small dust spots, remainder of frons shiny; pairs of spots on tergites 3 and 4 rounded at outer posterior corner, creating convex triangular spots of highly variable size, occupying from over half to less than a quarter of tergite length; spots on tergite 2 usually distinct; all-black specimens not rare. SIMILAR SPECIES Like M. scalare but arista with shorter hairs, although a microscope is needed to see this; shinier face is an easier field character, with almost no contrast between face and facial tubercle; male easily distinguished by less slender abdomen. Like M. certum; for differences, see that species. Very similar to M. mellarium and only males can be reliably identified: tergite 2 less elongated, best assessed in living specimens, in dead specimens side margins turn under abdomen; anterior part of scutum mainly with pale hairs; genitalia: postgonites (on tip of the hypandrium) usually shorter, like an equilateral triangle, but variable; females compared to M. mellarium more often with spots on tergite 2 and abdomen wider, but best left unidentified. Male like Platycheirus, especially P. clypeatus, but fore leg not modified and metasternum reduced.

Black females can be confused with Platycheirus but they have metasternum sharply reduced. OCCURRENCE One of the commonest species in open grassy places. ECOLOGY Found in any open vegetation with grasses including gardens, marshes, moorland and mountainsides. Often found low in vegetation, visits assorted low flowers, such as those of dandelions, agrimony, small umbellifers, plantains and flowering grasses. Also active during overcast weather. Larva feeds on aphids on many plant species.

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♀

head

♂

tergi tes 2–4 long er th a n wi d e

♂

postgonite

p o stg o n i te s

2 × l o nge r tha n w i de

bl a ck -ha i re d

♂ ♀

ab d o men

♂

genitalia

♂

♀

sc u tu m

♀

a bdo m e n bl a ck o r ne a rl y so fro ns

d usted

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♂

sc u tu m

l o ng ha i rs

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Intermediate Duskyface Melanostoma mellarium IDENTIFICATION 7–9 mm. Arista with short adpressed hairs, hairs not longer than half the width of arista at base; face narrow, shiny. Abdomen slender, intermediate between M. mellinum and M. scalare. Male: eyes meeting at an angle of c. 80–90°; frons shiny; scutum usually entirely covered with black hairs; anterior part of scutum with short hairs, about one-quarter scutellum length; metasternum sharply reduced in middle, diamond-shaped; fore leg normal shape; abdomen with three pairs of spots; abdomen with black hairs intermixed with pale hairs, especially along midline and close to posterior tergite margin; tergites 2–4 clearly longer than wide; sternite 2 c. 1.5 times longer than wide. Female: frons with pair of dust spots, otherwise shiny black; pairs of spots on tergites 3 and 4 rounded at outer posterior corner, creating a somewhat triangular shape; pair of spots on tergite 2 small or absent; size of yellow markings on abdomen variable, all-black specimens sometimes occur. SIMILAR SPECIES Only recently properly redescribed and distinguished from M. mellinum; genetically a distinct species, but morphologically very hard to distinguish from M. mellinum, characters subtle and seemingly variable, more species may be involved; both sexes slightly more elongated and with longer wings. Always distinguishable from M. scalare by shinier face and shorter hairs on arista. For differences with M. certum, see that species. Male: like Platycheirus angustatus, but fore leg normal. Like M. mellinum but tergites 2–4 slightly more elongated and scutum has black hairs; genitalia: postgonites (on tip of hypandrium) usually longer, like an isosceles triangle, but variable. Female: with current knowledge not reliably distinguished from M. mellinum. OCCURRENCE As

yet poorly known but present in low and high mountain ranges in Central Europe, Ireland (County Clare) and provisionally from several sites in the Scottish Highlands. ECOLOGY Grassy situations in upland areas, moorland, along flushes and brooks with sedges; in the British Isles from sheltered grassy areas in both native pine woodland and Aspen woodland. Larval biology unknown.

Dark Duskyface Melanostoma certum IDENTIFICATION 5–7 mm. A dumpy and dark Melanostoma.

Arista with short adpressed hairs, hairs not longer than half the width of arista at base; face and frons wide; face shiny with indistinct or thin grey dusting. Metasternum sharply reduced in middle, diamond-shaped. Wing: relatively short, like that of M. mellinum. Male: eyes meeting at an angle of c. 100° or more; frons distinctly dusted (unless abraded); scutum entirely covered with white–yellow hairs; anterior part of scutum with long hairs, length at least one-third scutellum length; spots on tergites 2–4 usually relatively small, those on tergite 2 may be absent; abdominal spots yellowish or greyish, often rather indistinct and heavily dusted; abdomen entirely covered with pale hairs, although a few black hairs may be present on posterior margin of tergite 4. Female: frons with large but often poorly defined dust patches, with light dusting between these, so frons above lunule dusted over full width; abdomen black or with tiny round spots; abdomen with whitish semi-adpressed hairs. SIMILAR SPECIES For differences with M. scalare, see that species. Male: like in M. mellinum and M. mellarium; best distinguished by longer hairs on anterior part of scutum, abdomen entirely covered with pale hairs, wider angle at which eyes meet, wider face and dusted frons; moreover, spots on abdomen small and dusted. Female: distinguished from melanistic or black Platycheirus by having sharply reduced metasternum; the usually all-black abdomen is a useful first indication, but as this also frequently occurs in M. mellinum and M. mellarium, best identified by combination of extensively dusted and broad frons and very short and ovate abdomen. OCCURRENCE Not exactly known because often confused with black individuals of other Melanostoma or Platycheirus species, but probably restricted to montane bogs in

high mountains over Europe. Within range covered by this book, only in Scotland and northern England. ECOLOGY Blanket bogs and boggy ground near streams in upland and montane areas. COMMENT Until recently known under the name M. dubium, but research on Scandinavian specimens discovered that it was actually undescribed and provided a new name, M. certum. All British material of ‘M. dubium’ in the strict sense seems to accord with M. certum and with experience can be distinguished from the variation that exists within M. mellinum.

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♀

a b d o me n

♂

te rgi te 5 w i th spo ts

l o w e r ha l f w i th pa l e pi t

♀

head

lightl y d usted

♂ undersid e 1 st tarsomere f ore l e g

♂

f o re l e g

l i ghtl y dusted

♀

♂

a b d o me n

spo ts sm a l l a nd no t re a chi ng a nte ri o r m a rgi n

uppe r ha l f w i th pa l e pi t, w i th bl a ck spo t be l o w pi t

♀

♂

underside 1 s t tarsomere f ore leg

head

♂

f o re l e g

s hi ny

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Common Sedgesitter Platycheirus clypeatus IDENTIFICATION 6–10 mm. A Platycheirus with pairs of orange spots on abdomen. Third antennal segment black. Anepisternum dull. Wing: cell bm entirely covered with microtrichia. Relatively broad bodied compared to closely related species. Abdomen not distinctly elongated. Male: fore tibia and fore tarsus widened; base of fore femur with dark streak; posterior side of fore femur at base with several bent black hairs; underside of tarsomere 1 of fore tarsus with central longitudinal groove, ending a third or a quarter from tip in a pit; underside of apical corner of fore tibia with a pointed extension being much longer than wide; tergite 2 ranging from a little wider than long to a little longer than wide; pair of spots on tergite 3 c. three-quarters of tergite length; tergite 5 black or with pair of small faint spots. Female: vertex dusted, although often slightly less dense than occiput; frons above lunule with slight dusting, connected with dust spots along eye margin; hind femur with black central ring, often faintly delineated or sometimes almost absent; spots on tergites 3 and 4 reach anterior margin, spots c. two-thirds of tergite length; tergite 6 black or at most with small faint yellow markings. SIMILAR SPECIES Both P. angustatus and P. europaeus have abdomen slenderer and usually base of cell bm bare; for more differences, see those species. For differences with P. ramsarensis, see that species. Male: like Melanostoma mellinum, but leg 1 of that species normal shape; like P. occultus, but that species has fore femur at base black all around, usually smaller spots on abdomen and pit on underside of tarsomere 1 of fore tarsus placed closer to centre. Female: unlike P. angustatus, which has four pairs of spots on abdomen; like P. occultus and P. europaeus, but these species

have vertex shiny and in P. occultus spots on tergites 3 and 4 not reaching anterior tergite margin. Also see the more yellowish P. fulviventris, scambus and immarginatus. OCCURRENCE A widespread and often common species in open areas, but numbers are low in heavily grazed grassland. ECOLOGY Both dry grassland (but susceptible to drought) and wet meadows, heathlands and moorland, even brackish marsh. Visits flowering grasses, sedges and plantain. Flies low through the vegetation, often relatively early in the day or when cloudy. Larva probably lives in leaf litter.

Dusky Sedgesitter Platycheirus occultus IDENTIFICATION 6–8 mm. A fairly dark lookalike of P. clypeatus.

Third antennal segment black. Anepisternum dull. Wing: cell bm entirely covered with microtrichia, sometimes base bare in female. Abdomen not distinctly elongated. Male: base of fore femur black all around; underside of tarsomere 1 of fore tarsus with central longitudinal groove, ending just before middle in a pit, black spot behind pit not reaching apical margin of tarsomere 1; underside of tarsomeres 2 and 3 of fore tarsus unmarked or with a single small black mark; underside of outer apical corner of fore tibia with a pointed extension not longer than wide; posterior side of fore femur next to bent white hair also with some bent black hairs; tergite 2 longer than wide; pair of spots on tergite 3 cover about three-fifths of tergite length; spots on tergite 3 usually not reaching anterior margin; tergite 5 mostly or entirely black. Female: vertex shiny, contrasting with dusted occiput; frons above lunule shiny or with only very little dusting; hind femur usually with black ring; orange spots on tergites 3 and 4 with rounded corners and not reaching anterior tergite margin, covering about half tergite length; sternite 2 wider than long. SIMILAR SPECIES Like P. clypeatus but spots on abdomen smaller. Male: like P. clypeatus, angustatus and europaeus, but the only one with base of fore femur black all around instead of with black streaks; like P. clypeatus with pit on underside of tarsomere 1 of fore tarsus, but pit lies just before middle instead of closer to tip; abdomen usually slenderer compared to P. clypeatus with tergite 2 distinctly longer than wide. Female: unlike P. clypeatus with vertex shiny; very similar to P. europaeus, but pairs of spots on tergites 3 and 4 not reaching anterior tergite margin, spots darker orange, abdomen less slender and cell bm usually without bare spot at base. OCCURRENCE Widespread and common in good habitat but

much more localised than P. clypeatus and more restricted to old, peaty wetlands. ECOLOGY Peaty wetlands with sedges, moorland, boggy areas in heathland, wet meadows along small streams. Behaviour like that of P. clypeatus, often found together. Larval biology unknown.

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a b d o me n

a bdo m e n sl e nde r

te rgi te 5 bl a ck

abdome n sl ender

t ho rax lat eral

♂ underside 1 st tarsomere f ore le g

V -sha pe d gro o v e so m e be nt bl a ck ha i rs

p o steri o r a n epi sternum sh i ny

♂

f o re l e g

♀

♂

a b d o me n

spo ts sm a l l

♂ unde rsi d e 1 st tarsomere f o re l e g t ho rax lat eral

p o steri o r a n epi sternum d usted

V -sha pe d gro o v e

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head

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f o re l e g

shi ny

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Slender Sedgesitter Platycheirus angustatus IDENTIFICATION 6–8 mm. A fairly slender Platycheirus. Third

antennal segment black. Posterior anepisternum shiny, contrasting with dusted anterior anepisternum. Wing: cell bm with bare spot at base, sometimes absent in male; alula just under three times longer than maximum width. Abdomen conspicuously slender. Male: fore tibia and fore tarsus widened; posterior side of fore femur besides bent white hair usually also with some bent black hairs; underside of tarsomere 1 of fore tarsus with V-shaped groove, with black marking below groove reaching apical margin; fore tibia on outer apical corner with blunt extension; pair of spots on tergite 3 cover at least four-fifths of tergite length; tergite 5 largely or entirely black. Female: dusting on frons restricted to triangular spots along eye margin, frons above lunule shiny; vertex shiny, contrasting with dusted occiput; abdomen shiny, slender and pointed; abdominal spots reddish; tergite 5 without pair of spots, black; sternite 2 longer than wide. SIMILAR SPECIES Slender appearance is a useful first identification feature in the field, female with pointed abdomen. It is the only Platycheirus from the clypeatus-group with shiny posterior anepisternum, as shiny as scutum, contrasting with dull anterior anepisternum – a subtle but, once-learnt, very reliable character. Male: V-shaped groove on underside of tarsomere 1 of fore tarsus distinguishes it from male P. clypeatus and P. occultus, in P. ramsarensis groove is closer to apical margin; like P. ramsarensis and P. europaeus but with alula narrower, black marking on underside of tarsomeres 2 and 3 of fore tarsus less extensive and some long black hairs at base of fore femur bent instead of straight; usually cell bm with bare spot at base, a character shared only with P. europaeus. Female: easily

recognised by three instead of four pairs of spots on abdomen, no spots on tergite 5; also, abdomen slender and pointed. OCCURRENCE Widespread and locally common in not-too-dry grassy environments. ECOLOGY Marshes, damp grasslands. Often sits on grasses and visits sedges, grasses and plantains in flower. Larva feeds on aphids.

Long Sedgesitter Platycheirus europaeus IDENTIFICATION 7–9 mm. A medium-sized, rather slender

Platycheirus. Third antennal segment black. Anepisternum dull. Wing: cell bm with bare spot at base, sometimes absent in male. Male: black hairs on fore femur not bent at tip; underside of tarsomere 1 of fore tarsus with V-shaped groove, black marking below groove reaching apical margin, also tarsomeres 2 and 3 with extensive black markings, usually reaching apical margin; fore tibia on apical corner with blunt extension; tergite 2 longer than wide; pair of spots on tergite 3 cover at most two-thirds of tergite length; tergite 5 largely or entirely black. Female: frons above lunule shiny; vertex shiny, contrasting with dusted occiput; hind femur with black ring; abdomen with roughly parallel sides, not pointed; tergite 2 a little longer than wide; sternite 2 longer than wide. SIMILAR SPECIES Similar to P. clypeatus, angustatus, occultus and ramsarensis. Usually with bare spot at base of cell bm, distinguishing it from all species except P. angustatus, but that species has posterior anepisternum shiny. Male: V-shaped groove on underside of tarsomere 1 of fore tarsus excludes P. clypeatus and P. occultus, in P. ramsarensis groove is closer to apical margin; see P. ramsarensis for more differences with that species; hairs on posterior side of fore femur not bent and abdomen a little less slender and with smaller spots compared to P. angustatus. Female: differs from P. clypeatus by shiny vertex, from P. angustatus by four instead of three pairs of spots on abdomen and from P. ramsarensis by entirely pale fore and mid tarsi; like P. occultus, but cell bm with bare spot at base, spots on tergite 3 reaching anterior margin, sternite 2 longer than wide and in living specimens spots on abdomen usually paler, but seemingly intermediate specimens can make identification very difficult. OCCURRENCE A widespread but local species for reasons not yet

fully understood, more common in wet low mountain ranges on the continent and in Scotland and Wales. ECOLOGY Damp open places in woodland mostly but not exclusively on base-poor soil, around scrubland on wet heathlands, flower-rich unimproved wet grasslands in small river valleys. More in the vicinity of forests compared to similar species. Visits flowering grasses and sedges. Larval biology poorly known.

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a b d o me n

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♂

♂

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f o re f e mu r

f o re l e g

a pi ca l ha l f ba re

underside 1 s t tarsomere f ore leg

head

V-sh a ped g ro o v e

♀

a b d o me n

♂ spo ts ro unde d

♂

♀ ♀

head

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l eg b l a ck, onl y kn ee p a l e

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Bare-legged Sedgesitter Platycheirus ramsarensis IDENTIFICATION 7–8 mm. A member of the clypeatus-group, most

resembling small P. clypeatus. Anepisternum dull. Wing: cell bm entirely covered with microtrichia. Male: face gradually widening downwards, eye margins not parallel; hairs on posterior side of fore femur present only on basal half, apical half bare; black hairs at base of fore femur not bent at their tip; underside of tarsomere 1 of fore tarsus with V-shaped groove, close to apical margin, black marking below groove reaching apical margin, also tarsomeres 2 and 3 with extensive black markings reaching apical margin; fore tibia at outer apical corner with pointed projection; tarsomere 1 of hind tarsus swollen, distinctly wider than hind tibia; tergite 5 largely or entirely black. Female: hind femur black, only very base and tip pale; outer or all tarsomeres of fore and mid tarsi brown, contrasting with yellower tibia; tergite 2 wider than long; tergite 6 black; posterior side fore femur with hairs only on basal half, outer half bare. SIMILAR SPECIES Both sexes can be distinguished from other members of the clypeatus-group by the hairs on the posterior side of fore femur: present only on basal half, outer half bare, in other species hairs found over full length. Male: V-shaped groove on underside of tarsomere 1 of fore tarsus distinguishes it from P. clypeatus and P. occultus; most similar to P. angustatus and P. europaeus, but groove on underside of tarsomere 1 of fore tarsus is closer to apical margin, fore tibia with a pointier apical projection and tarsomere 1 of hind tarsus swollen. Female: like P. angustatus and P. europaeus but cell bm entirely covered with microtrichia and tarsi of fore and mid leg darker, moreover, differs from P. angustatus by dull anepisternum and abdomen with four instead of three pairs of

spots. OCCURRENCE A northern species that, in the area covered by this book, occurs only in upland areas in Great Britain and Ireland. ECOLOGY Upland and moorland areas, wet patches of rushes beside moorland stream, bogs and flushes. Flies through grasses and visits Marsh marigold but probably also grasses and sedges. Not unusual to find it with P. podagratus, P. clypeatus and P. melanopsis. Larval biology unknown.

Variable Sedgesitter Platycheirus podagratus IDENTIFICATION 6–8 mm. A dark Platycheirus with oval or

rounded spots on abdomen. Third antennal segment black. Hind leg black, only knees and sometimes very base of femur and very tip of tibia narrowly yellow. Male: fore tibia gradually widening from base, but halfway abruptly widening; abdomen slender; tergite 5 predominantly or entirely black; spots on abdomen rounded. Female: frons with small dust spots, distance between spots equalling half the width of frons; fore and mid tarsi yellow to brown, hind tarsus black; pair of spots on tergite 2 rounded, those on tergites 3 and 4 often with outer posterior sides reduced, flattened, a pattern resembling that of female Melanostoma mellinum; tergite 6 black. SIMILAR SPECIES A fairly easily recognisable Platycheirus: rounded spots on abdomen, especially in female, are distinctive and so is the almost entirely black hind leg. Male: fore tibia with distinctive shape, different from similar Platycheirus, widening abruptly halfway. Female: can be confused with Melanostoma females when shape of spots on abdomen is similar, but spots on tergites 3 and 4 usually connected with anterior margin of tergites and metasternum not reduced in middle. OCCURRENCE Localised in the range covered by this book; restricted to Great Britain and Ireland and the north of Denmark. ECOLOGY Upland and moorland areas, wet patches of rushes beside moorland streams, bogs and flushes. Visits flowering grasses and sedges. Larval biology not known.

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a b d o me n

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te rgi te 6 w i th ye l l o w m a rk i ngs

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head

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h i n d f e mu r a n d ti b i a

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f ore f emur

w i th bl a ck ri ng

♂

f o re l e g

se v e ra l l o ng bl a ck ha i rs

base wi tho ut l o ng wh i te ha i r

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a b d o me n

♂

te rgi te 6 w i th ye l l o w m a rk i ngs

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head

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f ore f emur

whi te ha i r a t ba se

♂

f o re l e g w hi te ha i r a t ba se

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Blackspine Sedgesitter Platycheirus scambus IDENTIFICATION 8–9 mm. A fairly robust Platycheirus. Third

antennal segment black. Lower half of posterior anepisternum shiny, contrasting with dull upper half. Base of fore femur without long white bent hair; hind femur and hind tibia with black ring. Paired spots on tergite 2 cover over half tergite length. Male: fore tibia and fore tarsus widened; hairs on posterior side fore femur include a row of 4–6 black bristles; orange–yellow markings on tergite 5 variable, ranging from almost absent to (usually) clearly present; black lines between and among spots on tergites 2–4 well visible. Female: paired spots on tergites 3 and 4 usually not fully reaching side margin; tergite 6 largely yellow. SIMILAR SPECIES Spots on abdomen not as large as in P. fulviventris or P. perpallidus, but larger than in P. clypeatus. A very reliable and diagnostic character is shiny lower part of posterior anepisternum, dusted in all similar Platycheirus. Male: like other species in clypeatus-group, however posterior side of fore femur with row of long black hairs and base without long white bent hair; much like P. immarginatus, but that species has long white bent hair at base of fore femur and black band behind paired spots is narrower, while longitudinal band between spots is usually relatively wider; spots on tergite 2 larger compared to in P. clypeatus. Female: extensive orange markings on tergite 6 distinguish it from P. clypeatus; like P. fulviventris and P. perpallidus but also hind femur and hind tibia with black ring, and spots on abdomen slightly smaller, creating wider black longitudinal stripe between spots; like P. immarginatus but spots on tergite 2 larger, paired spots on tergites 3 and 4 more rectangular and without white bent hair at base of fore femur. OCCURRENCE Mainly a

northern species in Great Britain but abundant in lowland marshes on the continent in Belgium and the Netherlands, but sharply declining in northern Belgium. ECOLOGY Habitat preferences can vary across range but include lush water-side swamp with stands of Common reed and Reed sweet-grass but also damp, rushy meadows on base-poor soils (alongside species such as Microdon myrmicae) or damp upland meadows. Flies through tall vegetation and visits flowers of primarily sedges and grasses. Males hover among half-high vegetation. Larva feeds on aphids.

Comb-legged Sedgesitter Platycheirus immarginatus IDENTIFICATION 6–9 mm. Medium-sized Platycheirus with,

especially in male, large orange–yellow spots on abdomen. Third antennal segment black. Hind femur and hind tibia with black ring; posterior side of fore femur near base with long bent white bristle. Male: anepisternum dull; fore tibia and fore tarsus widened; fore femur below with c. six long scattered black hairs; longitudinal black medial stripe on tergites 2–4 much wider than black stripe behind pairs of spots, creating the typical appearance of an orange Platycheirus with a wide longitudinal black medial stripe; tergite 5 with orange markings. Female: dusting above lunule connected with dust spots along eyes; pair of spots on tergite 2 relatively small; paired spots on tergites 3 and 4 usually not fully reaching side margin, posterior margin of spots widening outwards, making spots slightly trapezoidal; black stripe behind paired spots in outer corners wider than width of hind tibia, but somewhat variable; tergite 6 with yellow markings. SIMILAR SPECIES Male: posterior side fore femur with a row of c. 6 long black hairs distinguishes it from all similar species except P. scambus, differentiated from that species by dusted anepisternum, narrower black stripe behind spots on abdomen, wider black longitudinal stripe between spots, and with long bent white bristle at base of fore femur. Female: like P. clypeatus but abdomen with larger paired spots and with large pair of spots on tergite 6; like P. fulviventris and P. perpallidus, but spots smaller: black stripes behind spots on tergites 3 and 4 wider than hind tibia, hind tibia usually with black ring and shape of third antennal segment differs from that of P. fulviventris; like P. scambus but spots on tergite 2 smaller, paired spots on tergites 3 and 4 usually with posterior margin not parallel to posterior margin of tergites, posterior side of fore femur with long

bent white bristle and anepisternum dusted. OCCURRENCE Mainly coastal areas in Europe, in the British Isles almost exclusively in upper saltmarsh and brackish ditches, usually where Sea clubrush is present. ECOLOGY Open, brackish marshlands, coastal grazing marsh, tidal marshes with reed beds, Sea clubrush and sedges. There is controversy whether the species occurs inland; in the past, it has often been confused with other species and inland observations almost always turn out to be of other species. Often visits flowering grasses, Sea clubrush and sedges. As with most Platycheirus, active mainly early in the day or in overcast weather. Larva feeds on aphids.

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a b d o me n

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te rgi te 6 w i th ye l l o w m a rk i ngs

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a bruptl y w i de ni ng

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3 r d a nten na l segm ent l a rg e a nd a n gul a r

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hind tibi a

yel l o w

head frons sh i ny

ha i rs bl a ck

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a b d o me n

♂

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head

terg i te 6 w i th yel l o w ma rk i ngs

3 r d a nten na l segm ent sm a l l a nd ro unded

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a b d o me n d e ta i l

♂

mid f emur

♂

head

f o re l e g gra dua l l y w i de ni ng

b l a ck b ent ha i rs ha i rs w hi te frons d usted

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Orange-legged Sedgesitter Platycheirus fulviventris IDENTIFICATION 6–9 mm. This Platycheirus gives a yellow first impression owing to large yellow spots on abdomen. Third antennal segment black, large and angular. Anepisternum dusted. Hind femur and hind tibia entirely yellow. Male: fore tibia considerably and abruptly widening, starting before middle; fore femur below with dense black hairs; pair of spots on tergite 4 very large so that black line behind and between spots is usually narrower than hind tibia; tergite 5 largely yellow. Female: dusting above lunule absent or if present not extensive and clearly separated from dust spots along eyes; pairs of spots on tergites 3 and 4 very large, reaching side margin in full width, black stripe behind paired spots at side margin usually narrower than width of hind tibia; tergite 6 yellow. SIMILAR SPECIES Male: combination of large spots on abdomen and fore tibia already sharply widening in basal part distinguishes it from all other Platycheirus; differs further from P. perpallidus by black instead of pale hairs on posterior side of fore femur and lacking tuft of black hairs on tip of mid femur. Female: shares large spots on abdomen with P. scambus, P. immarginatus and P. perpallidus; differs from first two by entirely orange hind femur and hind tibia and larger spots on abdomen, from P. perpallidus by larger and more angular third antennal segment, less dusted frons behind lunule and more sharply delimited dust spots along eyes. OCCURRENCE A very widespread and often common Platycheirus found over much of Europe. ECOLOGY All types of marshes with sedges, tall grasses and Common reed. Often visits flowers of Sea clubrush and sedges or sits on leaves of Common reed. Larva feeds on the

aphid Hyalopterus pruni on grass and grass-like flowering plants in wetlands.

Yellowcomb Sedgesitter Platycheirus perpallidus IDENTIFICATION 6–9 mm. A Platycheirus with very large yellow

spots on abdomen. Third antennal segment black, small and rounded. Anepisternum dull. Hind femur and hind tibia entirely yellow. Male: posterior side of fore femur with mainly pale uniform hairs; fore tibia gradually widening from base to tip; underside of mid femur near tip with a row of black bent hairs pointing towards femur base; pairs of very large spots on tergites 3 and 4 render black stripes hardly visible; tergite 5 with large orange spots. Female: dusting above lunule connected with dust spots along eyes; tergite 6 yellow. SIMILAR SPECIES Owing to large abdominal spots, can be confused with P. scambus and P. immarginatus, but especially P. fulviventris. Male: posterior side fore femur without row of black bristles, and spots on abdomen larger and with much narrower longitudinal stripe compared to P. scambus and P. immarginatus; like P. fulviventris but posterior side of fore femur with pale instead of black hairs, fore tibia widening gradually and underside of mid femur tip with tuft of black hairs pointing towards base. Female: compared to P. scambus and P. immarginatus, with larger spots on tergites 3 and 4, and hind femur and hind tibia entirely yellow; like P. fulviventris but third antennal segment smaller and less angular, and frons with denser dusting above lunule, dusting connected with dust spots along eyes; dust spots along eyes less demarcated from shiny frons. OCCURRENCE A montane species south of the range covered in this book, but in the range of this guide, and to the north, also in lowland areas using boggy areas. ECOLOGY On sedges, almost exclusively on Bottle sedge growing as emergent vegetation along the fringe of ponds, lakes, transition mire and poor fens. Settles on and flies through sedges, often some distance from the water’s edge. Visits flowers

of sedges. Larva feeds on aphids on sedges, mainly on Bottle sedge.

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a b d o me n

3 pa i rs o f spo ts

head d ust spo ts

ta rsus w i de ne d

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f ore f emur and tibia ti bi a w i th bl a ck m a rk i ng

head

3 r d a nten na l segm ent o ra n ge bel o w

tw o tuf ts o f bl a ck ha i rs w i th be nt ti p

♂

f o re l e g

fa ce dusted

♀

a b d o me n

i ndi sti nct spo ts

♂

s mall, d el i ca te speci es ta rsus no t w i de ne d

♀ ♀

f ore f emur and tibia

head

ti bi a ye l l o w si ngl e b l a ck h a i r

♂

f o re l e g

fa ce sh i ny tw o l o ng bl a ck bri stl e -l i ke ha i rs

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Grey-spotted Sedgesitter Platycheirus albimanus IDENTIFICATION 7–10 mm. A very common Platycheirus with

pairs of grey spots on abdomen. Third antennal segment orange below, sometimes hard to see in male. Male: mid trochanter without long spine; fore tibia sharply widening towards tip; fore tarsus with all tarsomeres clearly widened, gradually decreasing in width towards tip; posterior side of fore femur base with two tufts of black hairs with bent tip; spots on abdomen have a mica shine when tilted towards the light. Female: frons with grey dust spots; face dusted except facial tubercle; face not inflated; fore and mid tibiae with black marking on apical part; hind tibia largely black, a little yellow at very base; abdomen with pairs of grey-dusted spots on tergites 2–4; tergite 5 over twice as wide as long. SIMILAR SPECIES It is wise to get familiar with this common Platycheirus, so that you can detect the similar, rarer species. Male: the only Platycheirus with combination of grey spots on abdomen and fore tibia and fore tarsus clearly widened; sometimes spots on abdomen with yellowish shine, in that case similar to P. scutatus due to similar black hair tufts at base of fore femur, but spots lack yellow ground colour under the dusting, mid trochanter without long spine and tarsomere 2 of fore tarsus less wide. Female: shares grey spots on abdomen with P. ambiguus, P. sticticus and P. discimanus; for differences with P. sticticus, see that species; differs from P. ambiguus by having more distinct and not connected pairs of spots on abdomen and narrower vertex and face; differs from P. discimanus by having third antennal segment pale below, abdomen with three instead of four pairs of spots and face less wide. OCCURRENCE A widespread, frequent and common species with a very long flight period. ECOLOGY Various habitats

with scrubs and trees, forest edges, thickets, parks and gardens. Often flies just above ground in forest edge and visits low flowers. Males hover 1–3 metres above the ground. Larva feeds on aphids on grasses, herbs, bushes and trees.

Slender-handed Sedgesitter Platycheirus sticticus IDENTIFICATION 6–9 mm. A small, dark, delicate and inconspicuous Platycheirus. Third antennal segment pale below. Abdomen with small grey, sometimes indistinct, pairs of spots on tergites 2–4. Male: head relatively wide; face undusted, shiny; posterior side of fore femur with two long black bristlelike hairs; fore tibia and fore tarsus slightly widened, milky white. Female: frons and face entirely shiny, only eye margin narrowly dusted; lower part anepisternum shiny; fore femur with a single black hair one-quarter of femur length from tip, surrounding hairs pale; fore and mid tibiae yellow; tergite 5 less than twice as wide as long. SIMILAR SPECIES Male: like other Platycheirus with grey spots on abdomen but differs from P. albimanus by its smaller size, less widened fore tibia and fore tarsus and shiny face; differs from P. ambiguus by absence of curled hair on tip of fore femur and pale fore tibia, which is slightly widened; differs from P. discimanus by not sharply widened fore tarsus. Female: owing to combination of grey spots on abdomen and third antennal segment being pale below mainly mistakable with P. albimanus, best distinguished by its shiny face, otherwise on average smaller and more fragile, spots on abdomen often more indistinct, with black hair on fore femur one-quarter of femur length from tip, fore and mid tibiae yellow, tergite 5 less than twice as wide as long and lower part of anepisternum shiny; also like P. ambiguus, but that species has pairs of spots on abdomen larger, connected or seemingly absent and face distinctly dusted; like P. discimanus, but that species has third antennal segment black and abdomen with four instead of three pairs of spots. OCCURRENCE Widespread but very scarce. A rare and elusive species over much of its range. ECOLOGY Damp forest edges and forest glades, rough grasslands near forests.

Visits flowers including those of Common tormentil, small geraniums, Catsear and Wild angelica. Larval biology unknown.

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a b d o me n

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sca tte re d sho rt pa l e ha i rs

mid t ro c hant er

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f o re l e g

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head

se v e ra l da rk l o nge r ha i rs

re gul a r ro w o f pa l e ha i rs

fro ns n o t dusted fa ce dusted

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Many-tufted Sedgesitter Platycheirus scutatus IDENTIFICATION 7–9 mm. A Platycheirus with three pairs of small yellow spots on abdomen, sometimes somewhat reddish in female. Third antennal segment pale below. Male: face and frons silvery dusted, sometimes frons slightly more golden dusted; mid trochanter with long spine; fore tibia sharply widened; fore tarsus with basal 3–4 tarsomeres sharply widened, tarsomere 2 much wider than long; fore femur base below with two striking tufts of black hairs with bent tip; fore tibia just after middle with tuft of black hairs. Female: face much narrower than an eye; basal half of cell bm bare; fore and mid tarsi yellow or partly brownish; spots on abdomen rectangular to kidney-shaped. SIMILAR SPECIES Male: like P. albimanus but tarsomere 2 of fore tarsus much wider than long, spots on abdomen more yellow and mid trochanter with long spine; is part of a hard-to-identify trio with P. splendidus and P. aurolateralis, but these species have sharp contrast between undusted blackish frons and pale dusted face, clearly visible in the field (to a much lesser extent sometimes in P. scutatus); additional features that distinguish it from other two species are: undusted medial stripe on face is at most a fifth width of face, face with yellow hairs, although often some black hairs present, tarsomere 3 of fore tarsus less than twice as wide as long, tergite 2 with large bright-yellow spots, posterior margin of spots on tergites 3 and 4 usually almost parallel to anterior margin of tergites, black area between spots on tergite 3 c. 1.5–2 times as long as wide, for differences in hair patterns on mid tibia, see P. aurolateralis. Female: like P. transfugus; for differences, see that species; like P. peltatus and allies but scutum entirely shiny and abdomen with three instead of four pairs of spots, which have a different shape;

with current knowledge, indistinguishable from P. splendidus and P. aurolateralis. OCCURRENCE Until recently confused with two other species in the region covered by this book, but clearly the commonest of the trio, widespread and common all over Northwest Europe. ECOLOGY Broad-leaved forests, thickets, parks and gardens. Behaves inconspicuously, often found in the shade. Flies low through vegetation and visits flowers. Males hover at forest edges, 1–3 metres above the ground. Larva feeds on aphids on herbaceous vegetation and scrubs.

Splendid Sedgesitter Platycheirus splendidus IDENTIFICATION 6–8 mm. A Platycheirus with three pairs of slightly trapezoidal yellow spots on abdomen. Third antennal segment pale below. Male: face dusted; frons undusted, coppery–blackish; trochanter 2 with long spine; fore tibia sharply widened; fore tarsus with basal 3–4 tarsomeres sharply widened, tarsomere 2 much wider than long; fore femur below at base with two striking tufts of black hairs with bent tip; inner side mid tibia with scattered pale hairs shorter than half the width of tibia, anterior side at base with a few relatively short hairs and posterior side with two groups of long hairs; fore tibia just after the middle with tuft of black hairs. Female: abdomen with three pairs of rectangular to kidney-shaped red–yellow spots. SIMILAR SPECIES Male: like P. albimanus, but tarsomere 2 of fore leg much wider than long, abdomen with yellow spots and mid trochanter with long spine; very similar to P. scutatus and P. aurolateralis; best feature to distinguish it from P. scutatus is undusted black frons and silvery dusted face, creating a sharp contrast in colour and dusting between frons and face; other differences with P. scutatus are undusted medial stripe over face at least a quarter of width of face, face with black hairs although usually a few pale hairs also present, tarsomere 3 of fore tarsus at least twice as wide as long, tergite 2 with small pair of spots, posterior margin of spots on tergites 3 and 4 not parallel to anterior margin of tergites, black area between spots on tergite 3 about as wide as long or wider than long; like P. aurolateralis but has tergite 2 almost always with distinct pair of spots and hairs on mid tibia different (a reliable character but observer may need some experience to detect this): inner side with scattered short pale hairs shorter than half the width of the tibia on its narrowest point (dense longer hairs in P. aurolateralis), anterior side at base

with a few relatively short hairs and posterior side with two groups of long hairs. Female: like P. transfugus, for differences see that species; like P. peltatus and allies but has shiny scutum and abdomen with three instead of four pairs of spots, which have a different shape; with current knowledge, indistinguishable from P. scutatus and P. aurolateralis. OCCURRENCE Widespread but often localised in North-west Europe, distribution not very well known because not long recognised and only males can be identified. ECOLOGY At the edge of damp broad-leaved forests, on the transition from forest to flower-rich meadows, forested river valleys with moist meadows. Probably has a preference for more base-rich soils. Visits low flowers. Larva has been found both in aphid galls on elm and on Red campion.

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f o re l e g

♂

spo ts sm a l l or a bsent

♂

m a ny da rk l o ng ha i rs

head

de nse ro w pa l e l o ng ha i rs

frons n o t dusted , fa ce d usted

♂

♂

mi d ti b i a a n te ri o r si d e

mi d ti b i a i n n e r si d e

♀

a b d o me n

l a rge spo ts

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ta rso m e re 2 stro ngl y w i de ne d

da rk ri ng

♂

♀

head

head

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f o re f e mu r

♂

3 r d a n ten na l seg m ent pa l e b el o w

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Small-spotted Sedgesitter Platycheirus aurolateralis IDENTIFICATION 7–8 mm. A dark Platycheirus with pairs of

very small yellow spots on abdomen. Third antennal segment pale below. Male: face silvery dusted; frons undusted, coppery– blackish; mid trochanter with long spine; fore tibia sharply widened; fore tarsus with basal 3–4 tarsomeres sharply widened, tarsomere 2 much wider than long; fore femur base below with two striking tufts of black hairs with bent tip; fore tibia just after middle with tuft of black hairs; tergite 2 usually without pair of spots, tergites 3 and 4 in anterior corners with very small pairs of spots with sloping posterior margin. Female: abdomen with three pairs of rectangular to kidney-shaped red–yellow spots. SIMILAR SPECIES Male: like P. albimanus, but tarsomere 2 of fore leg much wider than long, and mid trochanter with long spine. Very similar to P. scutatus and P. splendidus, but usually with much smaller spots on abdomen, spots on tergite 2 usually absent, never the case in P. scutatus; other differences with P. scutatus are its undusted black frons and dusted face, creating a contrast in colour and dusting between frons and face; undusted medial stripe over face being at least a quarter of face width; face with black hairs although usually also with a few pale hairs; tarsomere 3 of fore tarsus at least twice as wide as long; tergite 2 without, or with, minute spots; posterior margin of spots on tergites 3 and 4 not parallel to anterior margin of tergites and black area between spots of tergite 3 much wider than long; like P. splendidus but tergite 2 usually without spots, spots on tergite 3 and 4 smaller and hairs on mid tibia different: on inner side of mid tibia, from base to well over halfway with dense and regular row of pale hairs of similar length, about as long as width

of tibia; anterior side with distinct long hairs at base, hairs longer than tibia width; posterior side with long hairs over full length. Female: with current knowledge indistinguishable from those of P. scutatus and P. splendidus; differs from other Platycheirus except P. transfugus by combination of abdomen with three pairs of spots, third antennal segment pale below and scutum entirely shiny; for differences with P. transfugus, see that species. OCCURRENCE A widespread but rare species although distribution insufficiently known, the scarcest of the trio with P. scutatus. ECOLOGY Clearings in wet forests, wet rough grassland along forest edges, often near streams and rivers. Visits flowers in the shade and partial shade. Larval biology unknown.

Wood Sedgesitter Platycheirus parmatus IDENTIFICATION 9–11 mm. A large sturdy Platycheirus with rectangular orange–yellow spots on abdomen. Third antennal segment reddish below. Male: posterior side fore femur with long thin hairs; fore tibia widened; fore tarsus with basal two tarsomeres sharply widened, tarsomere 2 twice as wide as long; mid femur and mid tibia normal shape. Female: dust spots on frons small, distinct and triangular; sides of thorax shiny, only slightly dusted; anterior corners of scutum dusted; underside of katepisternum with long hairs; fore and mid femora with distinct black ring; abdomen widely oval with pairs of four large spots, spots on tergites 3 and 4 widely rectangular and clearly separated from anterior tergite margin. SIMILAR SPECIES Male: shape of fore leg like that of P. peltatus and allies, but mid femur and mid tibia normal shape, tarsomere 2 of fore tarsus much wider and posterior side of fore femur with long regular hairs. Female: reminiscent of P. scutatus but abdomen much wider and with four instead of three pairs of much larger spots; like P. peltatus and allies but underside of katepisternum with long hairs, fore and mid femora with distinct black ring, and spots on tergites 3 and 4 rectangular and clearly separated from anterior tergite margin; like P. tarsalis but third antennal segment reddish below. OCCURRENCE Restricted to the south and east of the area covered by this book, but also occurs in Scandinavia. Not known from Great Britain. ECOLOGY Forest edges and forest glades in large broad-leaved forests with rich undergrowth. Visits low flowers such as those of buttercup. Males sit on low leaves or herbs in forest edge and keep territory there. Larva described, but biology unknown.

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a b d o me n

l a rge spo ts

♂

ta rso m e re 2 no t m uch w i de ne d

♂

mid fem ur

♂

mid tibia

♀

♀

f ore f emur

mi d ti b i a

no rm a l l y sha pe d

bl a ck bri stl e -l i ke ha i rs

yel l ow

♂

♀

f o re l e g

a b d o me n

l a rge spo ts

♂

♂

♂

m id femur

mid tibia

h a i rs po i nti n g to b a se

♀

mi d ti b i a

constri cti on a nd swel l i n g

bl a ck bri stl e -l i ke ha i rs

♂

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White-spotted Sedgesitter Platycheirus peltatus IDENTIFICATION 8–10 mm. A relatively large Platycheirus with

yellow spots on abdomen. Third antennal segment reddish below. Male: fore tibia widened; only tarsomere 1 of fore tarsus sharply widened; fore femur below with a row of black bristle-like hairs; anterior side of mid femur just after middle with cavity; apical part mid tibia constricted, tip swollen. Female: katepisternum below with short hairs; fore and mid femora yellow, at most with some brown smudges; mid tibia normal shape or with slight swelling apically; spots on tergite 2 large, almost or entirely reaching anterior tergite margin; paired spots on tergites 3 and 4 trapezoidal, posterior margin oblique. SIMILAR SPECIES Part of a trio with very similar P. amplus and P. nielseni. Male: fore leg roughly like that of P. parmatus but tarsomere 2 of fore tarsus less wide and posterior side of fore femur with black bristle-like hairs; much like P. amplus and P. nielseni but tibia 2 lacks the successive constriction and widening at the tip of P. nielseni and arrangement of hairs different from P. amplus. Female: differs from P. parmatus by short hairs on lower part of katepisternum (long in P. parmatus), having yellow fore and mid femora, and different shape of pairs of spots on abdomen; very similar to P. nielseni and P. amplus and differentiation not always possible; typical specimens distinguished from P. amplus by larger spots on tergite 2 reaching anterior corners of tergite, but some specimens have smaller spots so identification not certain; unlike in P. nielseni, mid tibia gradually widening from base to tip; if with swelling on outer fifth, this swelling minimal and following characters helpful, but do not always work: dusting on frons more extensive and less clearly defined; tip of abdomen wide, caused

by relatively wide posterior margin of tergite 5 and relatively short and wide tergites 6 and 7. OCCURRENCE Still widespread and rather frequent, but declining in northern Belgium and possibly also in Great Britain. ECOLOGY Marshes, wet tall herb-rich grasslands, meadows along streams. Sits on leaves and visits assorted flowers. Males hover up to 1 metre above the ground over marshy, grassy vegetation. Larva preys on aphids.

Nielsen’s Sedgesitter Platycheirus nielseni IDENTIFICATION 8–10 mm. A fairly large Platycheirus with yellow spots on abdomen. Third antennal segment pale below. Male: fore tibia widened; fore tarsus with only tarsomere 1 sharply widened; fore femur below with a row of black bristle-like hairs; tip of mid tibia with constriction followed by abrupt swelling, where swelling starts hairs are longer and point towards tibia base. Female: fore and mid femora yellow, at most with some brown smudges; underside of mid tibia with distinct swelling on outer fifth, sometimes preceded by a constriction; spots on tergite 2 large, reaching or almost reaching anterior tergite margin; spots on tergites 3 and 4 trapezoidal, posterior margin oblique. SIMILAR SPECIES Male: fore leg roughly like that of P. parmatus, but posterior side of femur with black bristle-like hairs and tarsomere 2 of tarsus less wide; much like P. peltatus and P. amplus but mid tibia distinctive: in P. nielseni constriction before swelling on apical half is most pronounced, and only P. nielseni with a tuft of hairs on swelling, hairs pointing towards tibia base. Female: differs from P. parmatus by entirely yellow fore and mid femora; distinguishing it from P. peltatus and P. amplus problematic and sometimes impossible, for indicative characters, see P. peltatus. OCCURRENCE Over most of Great Britain and very localised in northern and central Germany. ECOLOGY Wet meadows and bogs along streams mainly in upland areas. Also in and near forest. Visits flowers, up to 2 metres above the ground. Males hover in loose swarms along bushes. Larval biology unknown.

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sm a l l spo ts

♂

♂

a b d o me n

♀

m id t ib ia

mid tibia

triangular fan of long black hairs h a i rs po i nt to wa rd s ti p

normal s hape

bl a ck bri stl e -l i ke ha i rs

♂

f o re l e g

♀

♂

♂

a b d o me n

spo ts do no t re a ch a nte ri o r m a rgi n

ta rsus no t m uch w i de ne d

head

♂

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Northern Broadhand Sedgesitter Platycheirus amplus IDENTIFICATION 7–9 mm. Relatively large Platycheirus, abdomen

with pairs of yellow spots. Third antennal segment reddish below. Male: fore tibia widened; only tarsomere 1 of fore tarsus sharply widened; fore femur below with a row of black bristle-like hairs; underside of mid tibia near tip hardly modified, with a triangular fan of long black hairs near base and on upper side with a tuft of black hairs just beyond middle pointing towards tip. Female: fore and mid femora yellow, at most with some brown smudges; mid tibia normal shape, without distinctive constriction and swelling at tip; spots on tergite 2 small, not reaching anterior tergite margin; posterior margin of spots on tergites 3 and 4 slightly oblique. SIMILAR SPECIES Male: fore leg roughly like that of P. parmatus, but posterior side of femur with black bristle-like hairs and tarsomere 2 of tarsus less wide; the smallest of the trio including P. peltatus and P. nielseni, best identified by mid tibia: only a little modified, a triangular fan of long black hairs on underside near base and on upper side with a tuft of black hairs just beyond middle pointing towards tip, versus in other two species, mid tibia either strongly modified or with hairs different. Female: differs from P. parmatus by entirely yellow fore and mid femora; much like P. peltatus and P. nielseni and often indistinguishable, most important indicative character being pair of spots on tergite 2: small, slightly triangular or crescent-shaped, not reaching anterior tergite margin, thus not as large and rectangular as in the other two species; at least P. peltatus can also have such small spots, making certain identification impossible; paired spots on tergites 3 and 4 slightly more rectangular; mid tibia not distinctly swollen at tip like in P. nielseni. OCCURRENCE A species of upland areas and

mountain ranges, often very localised. ECOLOGY At the edge of poor fen and moorland flushes with sedges, often near bushes. Flies through grassy vegetation and visits flowers including those of Common tormentil, Cow parsley and buttercups. Males hover within 1 metre of the ground in open spots among higher grassy vegetation. Larval biology unknown.

Fragile Sedgesitter Platycheirus complicatus IDENTIFICATION 8–11 mm. A Platycheirus with white–yellow to pinkish spots on abdomen. Third antennal segment black; mouth edge protruding as much as facial tubercle or a little beyond. Scutum shiny. Male: fore tibia normal shape; tarsomere 1 of fore tarsus elongated, gradually slightly widening towards tip and with a small black spot in outer apical corner, tarsomere 2 square, remaining tarsomeres normal shape; tarsomere 1 of hind tarsus hardly wider than hind tibia; hind tibia without tuft of black bristly hairs; spots on abdomen with thin grey dusting; spots on tergite 2 round or triangular, widely separated from anterior tergite margin; spots on tergite 3 occupy about half the length of tergite. Female: frons with pair of large, sometimes fused grey dust spots; vertex shiny; scutum with short dark hairs, length of hairs equalling length of an ocellus; spots on tergite 2 at most as long as wide and widely separated from anterior tergite margin; spots on tergites 3 and 4 rectangular. SIMILAR SPECIES Combination of protruding face, black third antennal segment and shape of fore tarsus in male distinguishes it from all Platycheirus except P. manicatus and P. tarsalis; male differs from these by narrower tarsomere 1 of fore tarsus; moreover, male differs from P. manicatus by shiny scutum, smaller abdominal spots and less protruding mouth edge, and from P. tarsalis by lacking tuft of black hairs on hind tibia; female differs from P. manicatus by shinier vertex, frons and scutum, and from P. tarsalis by smaller spots on tergite 2 and shorter and darker hairs on scutum. OCCURRENCE In the range covered by this book, only a handful of records from a low mountain range in eastern Belgium and from low mountains in Germany. Not known from Great Britain. ECOLOGY Along tracks in damp forest, at the edge of small forest glades, both in broad-leaved and

spruce forests. Visits low flowers including those of Water avens and small geraniums.

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a b d o me n

scu tu m d ul l

♂

♂

head

♀

head

f ro ns duste d

m o uth ed ge protrudi ng

♂

♀ ♂

scutu m sh i ny

f o re l e g

a b d o me n

l a rge spo ts

tuft o f b l a ck b ri stl y h a i rs

♂

♀

head

mouth ed ge l ess protrudi ng

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f ro ns pa rtl y duste d

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Dull-backed Sedgesitter Platycheirus manicatus IDENTIFICATION 9–10 mm. A large Platycheirus with extensive

dusting and a distinctive protruding face. Third antennal segment black; mouth edge protruding distinctly beyond facial tubercle. Scutum thickly dusted, often with dull longitudinal stripes. Orange–yellow spots on abdomen with posterior inner corner rounded. Male: fore tibia normal shape; fore tarsus with basal two tarsomeres sharply widened, remaining tarsomeres normal shape; hind tibia without tuft of black bristly hairs; tarsomere 1 of hind tarsus strongly swollen; spots on abdomen elongated, occupying at least two-thirds of length of tergites. Female: frons and vertex entirely dusted; spots on tergite 2 not reaching anterior corners of tergite; spots on tergites 3 and 4 with rounded posterior margin. SIMILAR SPECIES Shares black third antennal segment, protruding face and shape of fore leg with P. complicatus and P. tarsalis, but spots on abdomen larger and scutum dusted; male with more protruding face and hind tibia without tuft of black bristly hairs, and female with dusting on frons and vertex more extensive. OCCURRENCE A very widespread species occurring in a variety of open habitats over most of Europe. ECOLOGY Large open grassy areas including marshes, salt marshes and cropland. Flies low over and through vegetation. Visits flowers including those of thistles, buttercups, white umbellifers and Sea aster. Larva feeds on aphids.

Shiny-backed Sedgesitter Platycheirus tarsalis IDENTIFICATION 8–11 mm. A fairly large Platycheirus with pale

orange–yellow spots on abdomen. Third antennal segment black; mouth edge protruding as much as or a little beyond facial tubercle. Scutum shiny or with patches of fine dust. Male: fore tibia normal shape; fore tarsus with only basal two tarsomeres sharply widened; hind tibia with tuft of black bristly hairs; tarsomere 1 of hind tarsus swollen; spots on tergite 2 elongated triangular and (almost) reaching anterior corners of tergite, those on tergite 3 about half tergite length. Female: frons with pair of large grey dust spots normally merged into a band; vertex shiny or lightly dusted; scutum with pale hairs, hairs 1.5–2 times longer than an ocellus; spots on tergite 2 longer than wide, reaching anterior corners; spots on tergites 3 and 4 rectangular. SIMILAR SPECIES Combination of protruding face, black third antennal segment and shape of fore tarsus in the male distinguishes it from all Platycheirus species except P. complicatus and P. manicatus; see P. complicatus for differences with that species; male differs from P. manicatus by shiny scutum, tuft of black bristly hairs on hind tibia and smaller spots on abdomen, female differs from P. manicatus by shiny scutum and more extensively shiny frons and vertex. OCCURRENCE Very localised and scarce in most of continental North-west Europe, but widespread and locally common in Great Britain. ECOLOGY Wet broad-leaved forests with rich undergrowth, forest edges, forest glades and along forest tracks, forested river valleys. Often to be found in partial shade and in the forest interior. Flies low through lush herb layer and visits flowers such as those of Garlic mustard, Honesty, bluebells and Greater stitchwort. Larval biology unknown.

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fro ns i n fl a ted a n d d usted

♀

a b d o me n

♂

ti bi a a nd ta rsus no t w i de ne d

♂

head

curl e d ha i r

♂ ♀

f o re l e g

head

♀

a b d o me n

♂

ti bi a a nd ta rsus no t w i de ne d

♀

spo ts yel l o w whi te, d usted

head

curl e d ha i r

♂

f o re l e g

fa ce wi d e

♀

a b d o me n

♂ v e ry l o ng a nd sle nde r a bdo m e n

♀

hea d

ti bi a a nd ta rsus no t w i de ne d

curl e d ha i r very l ong a n d sl en der a bdo m en

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Blackthorn Sedgesitter Platycheirus ambiguus IDENTIFICATION 7–9 mm. A big-headed Platycheirus with grey

spots on abdomen. Third antennal segment pale below. Wing: base of cell bm bare. Male: face swollen, with silvery white dusting; haltere knob dark brown; fore leg of normal shape, not widened; fore femur below with a row of black bristle-like hairs, apical hair distinctly curled. Female: face dusted, frons with dust spots; fore and mid femora with wide dark ring; at least basal quarter of hind femur yellow; pairs of spots on tergites 3 and 4 large, occupying over half of width of tergite, often fused to a band, with sometimes hardly discernible metallic sheen, sometimes abdomen appears entirely black. SIMILAR SPECIES Male: in region covered by this book, the only Platycheirus with combination of grey spots on abdomen and normally shaped fore leg; shares black curled hair on tip of fore femur with P. immaculatus and P. transfugus, but former with entirely black and more elongated abdomen and latter with yellow spots on abdomen, hairs on posterior side of fore femur less

bristle-like and haltere knob yellow. Female: shares third antennal segment pale below and dusting on face with P. albimanus but has wider face and frons, more indistinct spots on abdomen, partly fused into bands and hind femur more extensively pale at base; occasionally other Platycheirus or Melanostoma species can have all-black abdomen, so identification needs care, make sure abdomen has faint dust bands. OCCURRENCE Widespread but localised, often near flowering Prunus (especially Blackthorn) in early spring. ECOLOGY Forest edges, open landscapes with hedges of Blackthorn and hawthorn. Mainly found near sheltered earlyflowering bushes. Larva feeds on aphids, and seems to specialise on those using Prunus species such as Blackthorn and Bullace.

Curlyhair Sedgesitter Platycheirus transfugus IDENTIFICATION 6–8 mm. A small Platycheirus with three pairs of

orange–yellow spots on abdomen. Third antennal segment usually pale below. Scutum shiny. Haltere knob yellow. Pairs of orange– yellow spots on tergites 2–4 not reaching side margin. Male: eyes meeting at an obtuse angle, 105–120°; fore tibia and fore tarsus normal shape, not widened; outer half of fore femur with sparse row of at least five rather long, thin and hair-like bristles below and one only slightly longer, curly bristle at tip; abdominal spots silver–grey, brown or pale yellow, with or without silver– grey dusting. Female: frons with lateral dust spots, connected along eye margin with dusting on face; face dusted except facial tubercle; face wide, slightly wider than an eye; base of cell bm bare; tarsi dark above; spots on tergites 2–4 usually distinctly wider than long, those on tergite 2 small and crescent-shaped, those on tergites 3 and 4 larger with rounded anterior margin and oblique posterior margin; spots on tergites 2–4 dusted when viewed obliquely from front or side. SIMILAR SPECIES Male: shares black curled hair on tip of fore femur only with P. immaculatus and P. ambiguus, easily separated from former by less elongated

abdomen and presence of abdominal spots; like P. ambiguus but spots on abdomen yellow–white and weakly dusted, posterior surface of fore femur with longer and only slightly thickened hairs before curled hair and haltere knob yellow. Female: shares third antennal segment being pale below and abdomen with three pairs of small orange–yellow spots with P. scutatus, P. splendidus and P. aurolateralis, but face wider, slightly wider than an eye instead of much narrower than an eye, only base of cell bm bare instead of at least half of cell bm bare and tarsi darker. OCCURRENCE In the area covered by this book, restricted to a handful of locations in Denmark. Not known from Great Britain. ECOLOGY Open areas in broad-leaved and coniferous (spruce and pine) forests. Visits low flowers in the undergrowth. Larval biology unknown but probably feeds on aphids.

Needle Sedgesitter Platycheirus immaculatus IDENTIFICATION 6–8 mm. A dark, inconspicuous and very slender Platycheirus. Third antennal segment pale below; face shiny, dusting largely restricted to eye margin. Metasternum not reduced (as in all Platycheirus). Wing: cell bm entirely covered with microtrichia. Abdomen very slender and elongated. Male: fore tibia and fore tarsus normal shape, not widened; fore femur with a row of black bristle-like hairs below, apical hair distinctly curled; abdomen all black with bluish sheen, without spots. Female: frons shiny with two small distinct lateral dust spots; fore and mid femora yellow; hind femur with black ring on apical half; abdomen entirely black or with very indistinct grey dust spots; tergites longer than wide. SIMILAR SPECIES Among Platycheirus species, easily recognised by all-black, very long and slender abdomen. Melanistic or otherwise very dark Platycheirus or Melanostoma can be all black too (often intersexes), but abdomen always less long and elongated, and Melanostoma has metasternum greatly reduced. Like P. ambiguus but besides more elongated and blacker abdomen, has cell bm entirely covered in microtrichia, in male

mid femur below without yellow bristle and in female face shiny. OCCURRENCE In Central Europe, mainly in mountain ranges, only a few observations in the south of the area covered by this book. Not known from Great Britain. ECOLOGY Humid spruce and fir forest, woodland rides in spruce and fir plantations. Dwells inconspicuously along forest edges, often low between vegetation. Visits willow catkins and low flowers. Larval biology unknown.

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a b d o me n

a bdo m e n w i th 4 pa i s o f spo ts

♂

♂

head f ro ns w i de a nd shi ny

♀

head ti bi a a nd ta rsus no t w i de ne d

3 r d a nten na l segm ent bl a ck

♂

♀

f o re l e g

a b d o me n

♂

s po ts sm a l l or a b sent

♂

head

♀

♂

ta rso m e re 3 w i de ne d

f ro ns shi ny

♂

head

♀

f o re l e g

a b d o me n

ti bi a a nd ta rsus no t w i de ne d

♂

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Broad-fronted Sedgesitter Platycheirus discimanus IDENTIFICATION 7–8 mm. A small dark compact Platycheirus with grey spots on abdomen. Head relatively large, wide and inflated; third antennal segment black. Male: mouth edge not protruding beyond facial tubercle; fore tibia normal shape, cylindrical; basal two tarsomeres of fore tarsus sharply widened, remaining tarsomeres not widened; fore femur with long black hairs below. Female: face and frons entirely shiny; vertex wide; third antennal segment about as long as wide; fore and mid femora all dark except tip; abdomen with four pairs of more-or-less rectangular grey dust spots. SIMILAR SPECIES Can be found in spring among commoner P. albimanus on blossoms and willow catkins. Being a small yet robust species, females can be mistaken for a Cheilosia, but face without orbital strip. Male: combination of fore tibia normal shape and fore tarsus with basal two tarsomeres widened only found also in P. manicatus and P. tarsalis, but these two species have mouth edge further protruding, are larger and have yellow spots on abdomen. Female: shares grey dust spots

on abdomen with P. ambiguus, P. sticticus and P. albimanus, but combination of black third antennal segment, abdomen with four instead of three pairs of spots, face and frons entirely shiny and wide vertex diagnostic. OCCURRENCE Often overlooked because of its early flight period and habit of staying high on flowering bushes. ECOLOGY Forest and forest edge of mixed and pine forests. Almost always to be found on willow catkins or blossoms of Blackthorn or similar. Males hover high in and around these bushes. Larval biology unknown.

Stocky Sedgesitter Platycheirus melanopsis IDENTIFICATION 7–9 mm. A robust Platycheirus with orange

spots on abdomen. Face with protruding mouth edge and facial tubercle, mouth edge not surpassing facial tubercle; antennae black. Scutum shiny. Male: fore tibia not widening; basal three tarsomeres of fore tarsus widened; pair of spots on tergite 2 small or absent. Female: frons and vertex shiny, with only narrow small dust spots along eye margin; fore femur mostly black at base; abdomen wide and oval; tergite 2 wider than long and with a rectangular pair of spots. SIMILAR SPECIES Stands out in the field by its robust appearance and shiny abdomen with orange spots. Owing to protruding face and black third antennal segment, mainly confused with P. manicatus, P. tarsalis and P. complicatus but more robust. Male: unlike in P. manicatus, P. tarsalis and P. complicatus, spots on tergite 2 small or absent and also tarsomere 3 of fore tarsus widened. Female: abdomen shorter and wider, with spots more orange compared to P. manicatus and P. tarsalis, also frons shinier with only small dust spots along eye margin. OCCURRENCE In the range covered by this book only in northern Great Britain. ECOLOGY Unimproved, montane grassland,

usually above the tree line. Flies low over the ground and visits low flowers. Males hover low above sheltered paths on scree or at hill-tops. Larva found in aphid colonies on a variety of plants, including thistles, bilberry or ferns.

Fourspot Sedgesitter Pyrophaena rosarum IDENTIFICATION 7–10 mm. An easily recognisable hoverfly owing to typical markings on abdomen. Antennae black but third antennal segment reddish-brown below. Wing: dark in middle. Abdomen black, tergite 3 with constricted white–yellow band, tergite 4 in anterior corners with small usually dark-yellow spots; sometimes markings on tergite 4 more extensive and sometimes tergite 5 with pair of narrow grey stripes. Male: fore leg normal shape. Female: femora predominantly black. SIMILAR SPECIES Because of unique markings on abdomen, not likely to be confused with other species. OCCURRENCE Widespread and locally common. ECOLOGY Lush freshwater habitats, marshes, rough meadows, damp woodland with open canopy and undergrowth of lush marshy vegetation. Flies through vegetation and visits flowers. Males hover up to 2 metres above the ground in open spots among the vegetation. Larval biology unknown. See comment at P. granditarsa (overleaf).

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a b d o me n

♂ pro tube ra nce

♂

♀

f o re l e g

a b d o me n

♂

♂

elongata

♀

♂

abdomen

obscuripennis

a bdo m e n v e ry l o ng a nd sl e nde r wi ng h ya l i ne

w i ng da rke ne d

f ro ns shi ny frons d usted

♂

head elongata

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h e a d obscuripennis

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Hornhand Sedgesitter Pyrophaena granditarsa IDENTIFICATION 8–11 mm. A distinctive hoverfly with predominantly orange abdomen. Antennae black. Wing: dark in middle. Male: tarsomere 1 of fore and mid tarsi with very striking protuberance. Female: femora entirely yellow; orange markings less extensive compared to male, for example, tergite 3 not entirely orange but with black posterior corners; exceptionally, all-black specimens occur. SIMILAR SPECIES Owing to predominantly orange abdomen, not likely to be confused with any Platycheirus, but might superficially recall Xylota segnis or Myolepta dubia, however – amongst other differences, hind femur not swollen and abdomen coloration different. OCCURRENCE Widespread and common in wetlands. ECOLOGY Different lush freshwater habitats such as marshes, lush meadows, riparian vegetation along ditches and lakes, but also raised bog and brackish marsh. Flies among tall marshy vegetation and often sits on rushes, grasses or Common reed. Visits buttercups and other marsh flowers. Larval biology

unknown. COMMENT Like P. rosarum, closely related to the genus Platycheirus and sometimes placed in that genus.

Migrant Flatbelly Xanthandrus comtus IDENTIFICATION 8–13 mm. A rather characteristic hoverfly with wide oval abdomen. Scutellum and face black. Tergite 2 with circular pair of spots, sometimes absent in female; tergites 3 and 4 with pairs of semicircular spots close to anterior margin, spots connected in male; spots in male orange and in female orange to white–yellow. SIMILAR SPECIES Like a large, sturdy Platycheirus, but differently proportioned, more similar to some species of the tribe Syrphini (many of the hoverflies with black and yellow markings on abdomen); differs from species of the tribe Syrphini by black scutellum and face, and when not flying always has wings closed. OCCURRENCE Widespread and possibly increasing. Is increasingly seen during late autumn and winter. Shows migratory behaviour and therefore can be found in different places and habitats. ECOLOGY In forest glades and at the edge of wet mainly broad-leaved forests with rich undergrowth, often in the vicinity of water. Frequently settles on leaves of bushes. Males hover 3–5 metres above the ground in sheltered spots. Visits flowers, including those of hawthorn, white umbellifers and ivy. Larva feeds on aphids on herbs and

trees, but also caterpillars of micro-moths and larvae of Alder leaf beetle.

Common Dainty Baccha elongata IDENTIFICATION 7–11 mm. Abdomen very long and slender, anterior part of abdomen even narrower than scutellum. Wing: ranging from transparent to dark. Tergites 2 and 3 narrower than 4 and 5; abdomen with restricted and variable white–yellow markings. SIMILAR SPECIES In the field, easily mistaken for something else than a hoverfly owing to behaviour and very slim body. Of hoverflies, likely to be confused only with Sphegina, but larger, even more slender, without thickened hind femur and in male eyes meeting. OCCURRENCE Widespread over the whole of Europe; never abundant. ECOLOGY Broad-leaved and coniferous forests and scrub vegetation, also in parks and gardens. A slow flyer, flies low through vegetation in the shade. Larva feeds on aphids in the shade on plants and bushes. COMMENT Besides B. elongata, also B. obscuripennis is sometimes recognised, although predominant view is that B. obscuripennis is a variant within B. elongata. In obscuripennis wing is on average darker and in males grey dusting on frons is absent; hopefully, future DNA research can shed some light on the status of obscuripennis. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 2 1 1

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♂

a b d o me n

u n d e rsi d e a b d o me n

♂ ste rni te 4 w i de

so m eti mes wi th red ma rki ngs

ge ni ta l i a sm a l l

surstyl us sm a l l pa ra m e re sm a l l

abdome n us ually all black

♂

♂

♂

g e n i ta l i a

u n d e rsi d e a b d o me n

ste rni te 4 sl e nde r

ge ni ta l i a l a rge

pa ra m e re l a rge curv e d

♂

g e n i ta l i a

w i th ke e l stra i ght

♂ pa ra m e re l a rge

♂

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Common Grass Skimmer Paragus haemorrhous IDENTIFICATION 4–6 mm. A diminutive black hoverfly. Eyes with uniform hairs, not with vertical stripes of hairs. Scutellum black. Abdomen usually black, sometimes with small amount of red in centre of posterior tergites; tergites without grey bands of hairs; hairs on posterior part of tergites 2–4 black and semi-erect. Male: sternite 4 approximately rectangular with straight posterior margin, similar to sternite 3; genitalia: small, paramere and surstylus relatively small. SIMILAR SPECIES Differs from all other Paragus except P. tibialis and P. constrictus by uniform hairs on eyes and black scutellum; in other Paragus species, hairs on eyes arranged in vertical stripes and usually scutellum with yellow posterior margin. Male: readily distinguished from P. tibialis and P. constrictus by smaller genitalia, and therefore sternite 4 not much narrower than sternite 3 and posterior margin of sternite 4 straight – with a good hand lens this can be assessed in the field. Female: like P. tibialis and P. constrictus but posterior part of tergites 2–4 with black instead of white hairs, in the other two

at least tergite 4 with all hairs white. OCCURRENCE Widespread in the whole of Europe in open dry habitats. ECOLOGY Dry environments such as dry and sparse grasslands, heaths, dunes, often at the edges of scrubland, often in the vicinity of brambles. Flies low above vegetation and sits on the ground or on low vegetation. Visits small low-growing flowers such as those of stitchwort, Mouse-ear chickweed or Common tormentil. Larva feeds on aphids.

Heathland Grass Skimmer Paragus tibialis IDENTIFICATION 4–6 mm. A very small, mainly black hoverfly. Eyes with uniform hairs. Scutellum black. Tergites without grey bands of hairs; abdomen black, but often with little red markings on posterior tergites; tergites 2–4 with erect white hairs, only a few semi-erect hairs on posterior margin. Male: genitalia large; sternite 4 with posterior margin curved inwards, causing sternite to be much narrower than sternite 3; paramere very large, about twice as long as surstylus, boomerang-shaped; inner margin of paramere curved, without keel. SIMILAR SPECIES Shares uniform hairs on eyes and black scutellum with P. haemorrhous and P. constrictus. Male: unlike P. haemorrhous, with large genitalia and narrow sternite 4, paramere so large that tip is visible without dissecting genitalia; much like P. constrictus, identification possible only after studying genitalia: paramere larger, with curved inner margin and without a keel. Female: unlike P. haemorrhous has tergites 2–4 with white hairs; much like P. constrictus but hairs on tergites 2–4 erect, only a few semi-erect hairs on posterior margin, whereas in P. constrictus hairs on posterior part adpressed. OCCURRENCE In region covered by this book, very localised and

restricted to specific warm habitats. Further south, increasingly common and in many types of open vegetation. ECOLOGY A species of dry and warm heathlands and dune grasslands. Also in sparse vegetation with open ground, such as around railway stations. COMMENT Although genitalia relatively large, in absolute terms they are still very small, so some skills are needed to mount the genitalia correctly; try to pull away the epandrium with surstylus so the paramere is well visible.

Constricted Grass Skimmer Paragus constrictus IDENTIFICATION 4–6 mm. A small mainly black hoverfly. Eyes with uniform hairs. Scutellum black. Tergites without grey bands of hairs; abdomen sometimes black, but usually with little red markings on posterior tergites; tergites 2–4 with adpressed white hairs, although frequently with some black hairs on posterior margin of tergites 2 and 3. Male: genitalia large; sternite 4 with posterior margin curved inwards, causing sternite 4 to be narrower than sternite 3; paramere large, about 1.5 times as long as surstylus; inner margin of paramere straight, with keel. SIMILAR SPECIES Shares uniform hairs on eyes and black scutellum with P. haemorrhous and P. tibialis. Male: unlike P. haemorrhous, with large genitalia and narrow sternite 4; very similar to P. tibialis, only distinguishable after studying genitalia: paramere smaller, with straight inner margin and with keel – a reference collection will help understanding these differences. Female like P. haemorrhous and P. tibialis, differs from former by having white instead of black hairs on tergite 4, from latter by having hairs on posterior part of tergites 2–4 adpressed instead

of erect. OCCURRENCE A coastal species in region covered by this book, but also inland and montane elsewhere. A very localised species, more so than P. tibialis. ECOLOGY Open habitats such as limestone pavements and dune grasslands with ample bare ground. Sits on ground or low vegetation. Larva undescribed, but probably preys on aphids.

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a b d o me n

stri pe s o f si l v e r dusti ng di sti nct

w i tho ut re d m a rk i ngs

pa ra m e re w i de

tw o te e th o f e qua l si ze

♂

g e n i ta l i a

♀

♂

a b d o me n

w i th re d m a rk i ngs

stri pe s o f si l v e r dusti ng i ndi sti nct

pa ra m e re na rro w l o w e r to o th tw i ce a s l a rge

♂

g e n i ta l i a

♀

a b d o me n

♀

ti p o f a b d o me n

tra nsv e rse sw e l l i ng

♂

hypa ndri um w i th po i nte d pro trusi o n

o ne to o th

♂

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Grey-banded Grass Skimmer Paragus pecchiolii IDENTIFICATION 5–7 mm. A dark Paragus with silvery bands on abdomen. Eyes with vertical stripes of hairs. Posterior margin of scutellum usually narrowly yellow, sometimes hardly visible. Abdomen black, tergites 2–4 with pair of distinct stripes of silver dusting, sometimes with yellow markings below stripes. Male genitalia: basolateral lobe of aedeagus with two teeth of equal size; paramere wide. SIMILAR SPECIES Abdomen can be all black, as often in the trio P. haemorrhous, P. tibialis and P. constrictus, but distinguished by eyes with vertical stripes of hairs and posterior margin of scutellum usually yellow. Very similar to P. albifrons but without red markings on abdomen and with more distinctive silver stripes of dust on abdomen; male genitalia different, parameres wider and basolateral lobe of aedeagus with two teeth of equal size. Differs from P. finitimus and P. testaceus by black abdomen. Specimens with yellow markings under silver stripes can resemble P. quadrifasciatus, but yellow markings on tergite 2 absent, as are dust spots on tergite 5 and female without distinctive tubercle on

tergite 7. OCCURRENCE A rather common species in large forests in continental North-west Europe. Not known from Great Britain. ECOLOGY Less xerophylic than other Paragus in the region covered by this book, in and around forests with open canopy, in forest glades, woodland rides, often also in yards. Flies low through vegetation and settles on sunlit leaves and visits flowers at the forest edge. Larva feeds on aphids.

Red-dotted Grass Skimmer Paragus albifrons IDENTIFICATION 5–7 mm. A blackish Paragus, usually with red

spots on abdomen. Eyes with vertical stripes of hairs. Posterior margin of scutellum yellow. Tergites 3 and 4 without stripes of silver dusting, but instead with stripes of long adpressed silver hairs that reflect at certain angles; typical specimens with round or triangular red spot on tergite 2 and with anterior half of tergite 3 red, these spots can be connected, but never reach side margin of tergites. Male genitalia: lower tooth on basolateral lobe of aedeagus twice as large as upper tooth; paramere narrow. SIMILAR SPECIES Differs from P. testaceus, P. finitimus and P. flammeus by red spots on abdomen being less extensive, not reaching side margin of tergites. Female: most similar to P. pecchiolii but typical specimens identified by extensive red markings on centre of tergites 2 and 3; in very dark specimens, red markings reduced to a small red dot in middle of tergite 2, but still distinguished from P. pecchiolii by absence of bands of silver dusting; do not mistake rows of adpressed silvery hairs on abdomen for dust stripes! Male has same differences with P. pecchiolii as female, although often with less extensive red on

abdomen and genitalia different: lower tooth on basolateral lobe of aedeagus twice as large as upper tooth and paramere narrow. OCCURRENCE A local species in the range covered by this book but expanding over the last decade on the continent. ECOLOGY Welldrained sparsely vegetated river dykes, warm ruderal vegetation along railways, quarries, well-drained short-cropped warm grasslands on sand, chalk or limestone. Sits on or flies low through vegetation and visits small flowers low to the ground. Larva feeds on aphids.

Red Grass Skimmer Paragus testaceus IDENTIFICATION 5–7 mm. Quite a robust Paragus with largely red

abdomen. Eyes with vertical stripes of hairs. Posterior margin of scutellum yellow. Amount of red on abdomen variable, ranging from entirely red to only a few tergites partly red, but red markings reaching side margin of tergites. Male genitalia: epandrium swollen, therefore much larger than surstylus; hypandrium ends with outer upper corner in a pointed protrusion; basolateral lobe of aedeagus about as long as wide and with only one tooth; no conspicuous tooth between hypandrium and lingula. Female: tergite 7 with transverse swelling. SIMILAR SPECIES Differs from P. pecchiolii and P. albifrons by more extensive red markings on tergites that reach side margin of tergites 3 and 4, and female with narrower black medial stripe on face. Like P. flammeus and P. finitimus; see those species for how to identify females; males best identified by genitalia: epandrium swollen, hypandrium ending at outer upper corner in a pointed protrusion and basolateral lobe of aedeagus with only one tooth. OCCURRENCE Very rare along the southern margin of the

range covered by this book. Clearly increasing northwards in Belgium over recent years. Still very local but often present in large numbers. Not known from Great Britain. ECOLOGY Dune grasslands, heathlands, along railways, on spoil tips. Prefers lowcropped and very sparse vegetation with much open ground. Flies low through open vegetation and visits low flowers. Larva feeds on aphids.

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♀

abdo me n

♂ sha l l o w de pre ssi o n

♀

ti p o f a b d o me n

l o ng pro trusi o n

♂

♀

g e n i ta l i a

a b d o me n

♂

no de pre ssi o n

♀

ti p o f a b d o me n

l o be tw i ce a s w i de a s l o ng

tw o te e th sl i ghtl y bul gi ng

♂

♀

g e n i ta l i a

a b d o me n

♂

♀

t ip o f ab d o m en

our o nl y Paragus w i th yel l o w m a rk i ngs on a bdo m e n

disti n cti ve tu bercl e

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♂

g e n i ta l i a

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Spiny Grass Skimmer Paragus finitimus IDENTIFICATION 5–7 mm. A fairly robust Paragus with mostly

red abdomen. Eyes with vertical stripes of hairs. Posterior margin of scutellum yellow. Male genitalia: with a conspicuous long pointed protrusion between hypandrium and lingula. Female: wide black medial stripe on face narrower below antennae than on facial tubercle; middle of tergite 7 with a shallow depression. SIMILAR SPECIES Shares mostly red abdomen with P. testaceus and P. flammeus; however, male genitalia distinctive: the only species with a conspicuous long pointed protrusion on transition from hypandrium to lingula; female differs from similar species by shallow depression on tergite 7, but there is some uncertainty as to whether this character is diagnostic. OCCURRENCE A very localised and scarce species. In Denmark and Scandinavia, mostly coastal, further south more inland and montane. Not known from Great Britain. ECOLOGY Well-drained chalk grasslands, grey dunes and unimproved heathy grasslands. Flies low, sits on low vegetation or visits flowers. Larval biology unknown.

Flaming Grass Skimmer Paragus flammeus IDENTIFICATION 5–7 mm. A fairly robust Paragus with mostly red abdomen. Eyes with vertical stripes of hairs. Posterior margin of scutellum yellow. Amount of red on abdomen variable but in male anterior part of abdomen usually black, remainder red; in female abdomen only red on central part; abdomen without conspicuous bands of silver hairs. Male: genitalia slightly bulging between hypandrium and lingula; basolateral lobe of aedeagus about twice as wide as long and with two teeth of equal size; hypandrium in outer upper corner not ending in a pointed protrusion. Female: face with parallel black medial stripe, sometimes narrowing above facial knob; tergite 7 normal shape, without depression or swelling. SIMILAR SPECIES Differs from P. pecchiolii and P. albifrons by more extensive red markings on tergites reaching side margin of tergites 3 and 4. Much like P. testaceus and P. finitimus; for differences in male genitalia, see those species; female distinguished from P. finitimus in having tergite 7 normal shape, and from P. testaceus by having wider dark band on face, occupying one-third instead of one-quarter of face, and dusty markings on forehead near eyes more developed.

OCCURRENCE A very local and scarce species throughout its whole range. Not known from Great Britain. ECOLOGY Well-

drained unimproved chalk grasslands. Flies low above vegetation and visits flowers. Larval biology unknown, but likely comparable to other Paragus.

Yellow-banded Grass Skimmer Paragus quadrifasciatus IDENTIFICATION 5–8 mm. A distinctive Paragus with yellow abdominal markings. Eyes with vertical stripes of hairs. Scutum anteriorly with two longitudinal dust stripes; posterior margin of scutellum yellow. Abdomen with yellow markings, ranging from pairs of small spots on tergites 2 and 3 to abdomen largely orange–yellow; tergites 3 and 4 usually with yellow interrupted grey-dusted stripes; tergite 5 with pair of greydusted spots. Male: lingula short and very broad. Female: unique among Paragus in possessing a distinctive tubercle on tergite 7. SIMILAR SPECIES Typical specimens easily recognised by extensive yellow markings on abdomen, all other Paragus in the range covered by this book have either red or no markings on abdomen. P. albifrons and P. pecchiolii sometimes have yellowish or orange markings under stripes of silver dusting; however, P. quadrifasciatus distinctive owing to more extensive yellow markings on tergite 3, tergite 2 always with yellow markings in centre and with pair of grey dust spots on tergite 5. Genitalia of male very different from that of all other Paragus and in female

distinctive tubercle on tergite 7 unique. OCCURRENCE One of the fastest expanding hoverflies on the continent, has colonised the whole of Belgium in just a few years. Not known from Great Britain. ECOLOGY Well-drained, open ground with ruderal vegetation of Prickly lettuce or sow-thistles, on gravel, rubble or pavements, brownfield land, in urbanised areas up to the city centre, quarries. Most Paragus fly just above the ground, but P. quadrifasciatus often flies higher through the inflorescences of, for example, Prickly lettuce, 0.5–1.5 metres above the ground. Larva feeds on aphids on plants such as Prickly lettuce and sow-thistle.

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♂

♀

onl y outer two ta rs o m e re s bl a ck

antenna

1 s t a nten na l seg m ent tw i ce a s l o ng a s 2 n d se gm e nt

♀

oute r thre e tars omeres black , fe mora partly bl a ck

a b d o me n l a te ra l

♂ terg i te 4 w i th bl a ck ha i rs

sc u te l l u m

ant enna

h a i rs scute l l um l o ng

3 r d s e gme nt twice as long a s 1 s t a n d 2 nd co m bi ned

♀

a b d o me n l a te ra l

♂

tergi te 4 w i th pa l e ha i rs

sc u te l l u m

ha i rs scute l l um sho rt

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Pine Longhorn Callicera rufa IDENTIFICATION 10–12 mm. A hoverfly with ginger-coloured hairs and long antennae. First antennal segment twice as long as second antennal segment; third antennal segment twice as long as first and second antennal segments combined; antennae fairly short in male. Scutum shiny. Wing: large parts of cell cua, cell br and cell bm bare. Legs pale, usually entirely pale except tarsomeres 4 and 5 of tarsi, although femora sometimes largely black in males; hind femur cylindrical, without kink or excavation. Abdomen shiny black; scutum and abdomen with ginger-coloured hairs but tip of abdomen to a variable extent with black hairs, especially in male. SIMILAR SPECIES Differs from C. aurata, C. aenea and C. spinolae by different length ratio of antennae but usually also by colour of hairs on body: ginger instead of goldenyellow. Like C. fagesii and C. macquarti but differs by normally shaped hind femur, pale tarsomere 3, shiny scutum and largely bare cell cua, cell br and cell bm. OCCURRENCE Can be common at hill-tops in areas with pinewoods. Flight period April–June on the

continent, but British records are mainly from June–August with occasional records into October. ECOLOGY Old coniferous forests, especially ancient pine forest but in southern England it has suddenly started to appear widely in mature pine plantations of species such as Corsican pine, having previously been known only from Scots pine areas of the Scottish Highlands. Females often visit broom, males sit on the trunk of pines, often on hill-tops. Larva lives in wet cavities in coniferous trees. COMMENT Callicera species are probably, to a large extent, arboreal and therefore rarely seen.

Dark Longhorn Callicera fagesii IDENTIFICATION 11–12 mm. A hoverfly with yellow–brown hairs and long antennae. First antennal segment twice as long as second antennal segment; third antennal segment twice as long as first and second antennal segments combined. Scutum black with dull longitudinal stripes; hairs on scutellum longer than first antennal segment; hairs on scutum and abdomen yellow–brown to grey–brown. Wing: almost entirely covered with microtrichia. Femora predominantly black; tibiae yellow but hind tibia usually dark at tip; tarsomeres 3–5 of tarsi black; underside of hind femur with a kink, followed by an excavation in which hind tibia fits. Ground colour of abdomen black with green metallic sheen, in females sometimes more golden; in males usually at least tergite 4 largely covered with black hairs. SIMILAR SPECIES Shares length ratio of antennae with C. rufa, but hind femur with excavation, legs darker, scutum dull and wing less bare. Much like C. macquarti and distinguished from it with difficulty; most important difference is longer hairs on scutellum; moreover, on average hairs on body browner, more often with black hairs on tergite 4, and hind tibia often with dark markings. Summer

specimens of C. fagesii have golden ground colour on abdomen and have paler and slightly shorter hairs, making distinguishing it from C. macquarti almost impossible. OCCURRENCE Rather widespread, but observations in the range covered by this book are erratic, likely owing to its rarity and elusive behaviour. Not known from Great Britain. ECOLOGY Broad-leaved forests with overmature trees, open landscapes and historical parkland with overmature trees; the availability of old trees with wet cavities is a prerequisite. An elusive arboreal species, often encountered when it comes down to drink. Larva lives in tree cavities in poplar, but likely also other broad-leaved trees.

Macquart’s Longhorn Callicera macquarti IDENTIFICATION 11–12 mm. A C. fagesii lookalike. First antennal segment twice as long as second antennal segment; third antennal segment twice as long as first and second antennal segments combined. Scutum black with dull longitudinal stripes; most hairs on scutellum not longer than first antennal segment; hairs on scutum and abdomen orange to white–yellow; tergites usually without black hairs. Wing: almost entirely covered with microtrichia. Underside of hind femur with a kink, followed by an excavation in which hind tibia fits; femora mostly black; tibiae yellow; tarsomeres 3–5 of tarsi black. Ground colour of abdomen shiny gold. SIMILAR SPECIES Like C. fagesii and C. rufa due to similar length ratio of antennae; differs from latter by hind femur with excavation, darker legs, dull scutum and wings more extensively covered with microtrichia; distinguished from C. fagesii with difficulty but scutellum with shorter hairs, also more often abdomen without black hairs and hind tibia always entirely yellow; females sometimes impossible to identify. OCCURRENCE A species of the Mediterranean Basin, occurs as far north as the south of

Germany, but considerable confusion exists over the difference with C. fagesii. Not known from Great Britain. ECOLOGY A strict autumn species (September–October) whereas C. fagesii flies mainly in spring, but with some individuals in summer as late as the beginning of September. Old broad-leaved forests including beech and oak. Larva has been found in cavities of old oaks. Probably lives high up in trees and comes down sporadically to drink but frequently visits flowers of ivy.

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a b d o me n

♂

a n te n n a

1 st a nd 2 n d se gm e nts co m bi ne d a s l o ng a s 3 r d

♀

mi d l e g

♂ e x te nsi v e l y bl a ck

a n te n n a

1 st a nd 2 n d se gm e nts co m bi ne d a s l o ng a s 3 r d

♂

f ro ns ha i re d

f ro n s

♂

♀

a n te n n a

hind margin dull

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mi d l e g

e x te nsi v e l y ye l l o w

1 s t a nd 2 n d se gm e nts co m bi ne d a s l o ng a s 3 r d

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Yellow Longhorn Callicera aenea IDENTIFICATION 11–13 mm. A large hoverfly with long antennae and shiny golden abdomen. First antennal segment as long as second antennal segment; third antennal segment as long as first and second antennal segment combined. Scutum thinly but distinctly dusted greyish over almost entire surface, with or without two or four distinct longitudinal dust stripes covering entire length of scutum; scutellum with long hairs, hairs on posterior margin of scutellum as long as scutellum itself, hairs on top of scutellum two-thirds or more scutellum length. Tarsi yellow or tarsomeres 3–5 dark, but not as black as base of femora; trochanters with pale hairs. Male: frons bare. Female: femora with extensive black markings. SIMILAR SPECIES Shares length ratio of antennae with C. aurata and C. spinolae. Differs from C. aurata by dusted scutum, longer hairs on scutellum and paler tarsi. Males differ from C. spinolae by bare frons, females by partly black femora, and both sexes by lack of distinctive dull bands near posterior end of tergites 2 and 3. OCCURRENCE A rare and very

elusive spring species for which the vast majority of observations are of hill-topping males. A spring species that usually flies well before C. aurata and C. spinolae. Not known from Great Britain. ECOLOGY Broad-leaved forests and other habitats with overmature trees. Seldom visits flowers. The only species of the ‘golden’ Callicera in area covered by this book in which the male shows distinctive, hovering behaviour near hill-tops, usually above forest tracks a few metres above the ground. Larva unknown, but probably lives in cavities of old trees.

Golden Longhorn Callicera aurata IDENTIFICATION 11–13 mm. A large shiny golden hoverfly with long antennae. Length ratio of antennae like in C. aenea and C. spinolae: third antennal segment about as long as first and second antennal segments combined; first antennal segment about as long as second antennal segment. Scutum shiny, except anteriorly two longitudinal grey stripes of dusting that stop abruptly between wing bases; scutellum with short hairs, hairs on posterior margin shorter than scutellum, hairs on top of scutellum not longer than half scutellum length; fore and hind trochanter partly covered with black hairs; tarsomere 1 and sometimes also tarsomere 2 yellow, contrasting with remaining tarsomeres, which are distinctly black. Male: frons bare. Female: femora with extensive black markings. SIMILAR SPECIES Shares length ratio of antennae with C. aenea and C. spinolae; however, in latter clear dull black bands are present near posterior end of tergites 2 and 3, male has long hairs on frons and female has femora more extensively yellow. Differs from C. aenea by having largely shiny scutum, short hairs on scutellum and black outer tarsomeres. OCCURRENCE Possibly the commonest Callicera in

Europe, or maybe less elusive because of its frequent flower visits. ECOLOGY Mature broad-leaved forest, historical parklands, open habitats with veteran trees or trees with tree holes. Seen relatively often on flowers compared to other Callicera, preferring conspicuous flowers of Devil’s-bit scabious, Field scabious, Teasel, Meadowsweet, blackberry and Dog rose. Very occasionally on ivy where it could be mistaken for C. spinolae. Larva has been found in cavities of various species of broad-leaved tree.

Ivy Longhorn Callicera spinolae IDENTIFICATION 11–13 mm. A large shiny golden hoverfly with dull bands on abdomen and with long antennae. Third antennal segment about as long as first and second antennal segments combined; first antennal segment about as long as second antennal segment. Tergites 2 and 3 near posterior margin with dull band over full width. Male: hairs on frons along eyes above antennae long, as long as hairs on eyes. Female: femora entirely yellow or at most black at very base. SIMILAR SPECIES Length ratio of antennae like in C. aenea and C. aurata, but tergites 2 and 3 posteriorly with dull band, male with long hairs on frons near eyes and female with femora entirely yellow or only narrowly black at base. OCCURRENCE A species of the Mediterranean Basin that has its northern range limit through Belgium and southern England, but expanding northwards on the continent. An autumn species: flight period September and October. ECOLOGY Broadleaved forests and historical parklands with overmature trees with cavities. Adults mostly found visiting ivy. Larva has been found in cavities of various broad-leaved trees. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 2 2 1

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a n te n n a e

♂

a n te nna e pl a ce d o n a f ro nta l pro m i ne nce

a b d o me n

1 st a nte nna l se gm e nt

sc u te l l u m

with a V- s hape d notch

po ste ri o r ha l f o f scute l l um bl a ck

♀

a b d o me n

♂

sc u te l l u m

scute l l um e nti re l y ye l l o w

♀

a b d o me n

♂

a n te n n a e

R 4 + 5 s traight

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Common Wasp Fly Ceriana conopsoides IDENTIFICATION 11–14 mm. Handsome wasp mimic. Antennae longer than head and on a frontal prominence; prominence about twice as long as first antennal segment; arista attached at tip of third antennal segment. Posterior half of scutellum black; metasternum with hairs. Wing: anterior margin dark; vein R4+5 with a V-shaped notch with a small appendage projecting from notch tip into cell r4+5. Usually top half of hind femur black for over half its length. Base of tergite 1 yellow; tergite 2 not or only slightly constricted. SIMILAR SPECIES Looks like a thick-headed fly (Conopidae), but antennae on a prominence and venation on wing different. Differs from Sphiximorpha subsessilis by presence of frontal prominence. Like C. vespiformis but larger, posterior half of scutellum black and metasternum with hairs. OCCURRENCE A widespread species over much of Europe, but scarce. Not known from Great Britain. ECOLOGY Forest glades and thickets in mixed and broad-leaved forest. Visits white umbellifers, Alder buckthorn, Spindle and hawthorn. Larva lives

in sap runs and wet cavities of broad-leaved trees, in particular poplar, oak and elm.

Southern Wasp Fly Ceriana vespiformis IDENTIFICATION 10–11 mm. A compact Ceriana, similar to a wasp

but also a thick-headed fly (Conopidae). Long antennae on a long frontal prominence, itself longer than first antennal segment; arista attached at tip of third antennal segment. Scutellum entirely yellow, rarely with a small black spot at tip; metasternum bare. Wing: anterior margin dark; vein R4+5 with a V-shaped notch with a small appendage projecting from notch tip into cell r4+5. Usually hind femur black in top half for less than half its length. Base of tergite 1 yellow; tergite 2 not constricted. SIMILAR SPECIES Like a thick-headed fly (Conopidae) but antennae on a prominence and venation on wing different. Like Sphiximorpha subsessilis but smaller, abdomen not constricted, scutellum yellow and with frontal prominence. Like C. conopsoides but smaller and more compact with proportionally bigger head and scutellum all yellow or with only a small black spot, whereas with clear black posterior margin in C. conopsoides; moreover, hind femur less extensively black and metasternum bare. OCCURRENCE A Mediterranean species with very few observations north of the Alps, recently seen in the Moselle Valley in Germany. Not known from Great Britain.

ECOLOGY Mediterranean oak forest, both tall forest and maquis.

Often seen visiting yellow umbellifers. Larva lives in sap runs, rotting roots and cavities of broad-leaved trees.

Northern Saprun Wasp Fly Sphiximorpha subsessilis IDENTIFICATION 12–14 mm. Spectacular wasp mimic with long antennae. Antennae much longer than head, not on a frontal prominence; arista attached at tip of third antennal segment. Wing: anterior margin dark; R4+5 with long appendage projecting into cell r4+5. Hind femur swollen. Base of tergite 1 black; tergite 2 distinctly constricted. SIMILAR SPECIES Very much resembling certain thick-headed flies (Conopidae) but venation on wing different, including false vein characteristic of hoverflies. Differs from Ceriana species by antennae attaching directly onto head, thus lacking frontal prominence; moreover, R4+5 at appendage almost straight and not V-shaped. OCCURRENCE Widespread in most of Europe, often rare but has sharply increased over North-west Europe owing to bleeding canker in Horse chestnut, amongst other factors. Not known from Great Britain. ECOLOGY Well-developed broad-leaved forests, historical parklands, tree lanes with poplars or Horse chestnut, with (over)mature or diseased trees with sap runs. Males do not hover but guard territories around tree trunks with

distinctive sap runs. Larva lives in sap runs of mainly broadleaved trees.

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e ye ba re

3 r d a nte nna l se gm e nt o ra nge f a ci a l tube rcl e ha rdl y di sce rni bl e

sp o ts

♂

head

♂

head

ha i rs o n e ye pa l e

♂

3 r d a nte nna l se gm e nt da rk

♀

head

spo ts

♀

a b d o me n

♂ spo ts

ha i rs o n e ye bl a ck

spo ts

♂

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head

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Spotted Garlic Eater Portevinia maculata IDENTIFICATION 8–9 mm. Medium-sized robust brown–grey hoverfly. Face protruding; facial tubercle poorly developed and hardly discernible; eyes bare; face bare; face with wide orbital strip; third antennal segment bright orange. Posterior margin of scutellum with bristles. Legs black but usually knees slightly paler. Abdomen with pairs of distinct grey-dusted spots on tergites 1–4. Male: eyes barely touch. Female: spots on tergite 3 often fused and spots on tergite 4 indistinct or absent. SIMILAR SPECIES Much like a Cheilosia, but lunule larger, eyes almost separated in male, facial knob indistinct and male genitalia very different. Specifically, similar to C. fasciata and C. semifasciata owing to predominantly black legs and grey dust spots on abdomen; however, eyes bare, third antennal segment bright orange and face strongly protruding, obscuring facial tubercle. OCCURRENCE Widespread but very localised. Can be very abundant at large patches of Ramsons, but generally a very local fly as is the case with the foodplant. ECOLOGY Broad-leaved forests with undergrowth of

Ramsons. Along streams, forest tracks and forest glades. Moves with a sluggish flight low near Ramsons and settles on leaves of the plant. Feeds on Ramsons flowers. Larva mines first the stem and later the corms of Ramsons.

Leafmining Blacklet Cheilosia semifasciata IDENTIFICATION 6–8 mm. Small elongated matt-bronze Cheilosia.

Eyes with pale hairs; face bare; third antennal segment brown– black or black; facial tubercle relatively low on face and, together with mouth edge, protruding forwards and downwards. Male: legs usually entirely black; abdomen with grey dust spots, best appreciated when viewed obliquely from front; abdomen short, sides parallel. Female: legs black, but tibiae pale at base; body with golden hairs; abdomen without dust spots, shiny bronze; sternites shiny or with thin dusting. SIMILAR SPECIES Male: shares combination of largely black legs, eyes with hairs and distinctive dust spots on abdomen only with C. fasciata, but is smaller, abdomen shorter and stockier and less hairy, hairs on eyes pale and legs darker (at most, knees a little pale, but tibiae not distinctly pale at base). Female: lacks yellow wing base of C. impressa; like C. cynocephala and C. carbonaria, but smaller, more elongated, third antennal segment not orange below, with golden abdominal hairs and bronze–green sheen instead of black or blue sheen; more elongated compared to C. morio, face narrower, third antennal segment black, and body with

bronze–green instead of black sheen; like C. bergenstammi, C. urbana and C. psilophthalma but third antennal segment black and legs darker, tarsi entirely dark, middle tarsomeres pale in other species; like C. mutabilis, but abdomen covered entirely with golden hairs instead of with large proportion covered with black hairs. OCCURRENCE On the North-west European continent, this is an anthropophilic species, locally abundant in such situations. ECOLOGY Forests in which the host plant Orpine occurs, but especially in parks and gardens. Mainly in habitats with Navelwort in Great Britain. Males hover along forest tracks and forest edges or settle on low leaves in sunlit places in forest, usually in groups. Larva mines the leaves of Orpine (on the continent) and mainly Navelwort in Great Britain.

Garlic Blacklet Cheilosia fasciata IDENTIFICATION 8–10 mm. A fairly large black Cheilosia with

distinct grey dust spots on abdomen. Eyes with dark hairs; face bare; orbital strip wide; face distinctly protruding downwards; third antennal segment brown–black or black. Legs largely black; however, basal third of tibiae pale, sometimes extreme tip as well. Both male and female with grey dust spots on abdomen; sternites with thick grey dusting, central area of scutum shiny. SIMILAR SPECIES Combination of distinctive grey dust spots on abdomen, relatively dark legs and eyes with hairs makes it quite easily identified, but male C. semifasciata shares these characters; male of that species, however, has pale hairs on eyes, is clearly smaller, has less thick or no dusting on sternites, has less distinctive grey dust spots on abdomen and has darker tibiae. In female, distinct dust spots on abdomen are shared only with Portevinia maculata but C. fasciata female eyes with hairs and third antennal segment black instead of bright orange. OCCURRENCE A fairly regular species at large stands of Ramsons on the continent, has been able to colonise some

isolated introduced urban populations of Ramsons over the last decades. Adults easily missed owing to very early flight season, but the conspicuous mines are easily detected and last until late spring. Not known from Great Britain. ECOLOGY Wet broadleaved forests with Ramsons. Flies low through vegetation, often near Ramsons, and settles on the leaves of this plant. Larva is a leafminer of Ramsons.

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a b d o me n

♂

ba se ti bi a e pa l e

♀

head

♂

♀

head

head

3 r d a n ten na l seg m ent o ra n ge f a ce w i de a nd ba re

♀

a b d o me n

♂

♀

head

♂

head

♀

head

f a ce ha i re d

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Spruce Blacklet Cheilosia luteicornis IDENTIFICATION 9–12 mm. A distinctive broad-faced Cheilosia.

Eyes with hairs; face bare; face very wide; orbital strip not narrow; third antennal segment dark or orange–brown and paler below, but in female often entirely orange or with only upper margin black. Usually, posterior margin of scutellum without bristles in male, with bristles in female; scutum anteriorly with indistinct dusted longitudinal stripes. Calypter pale yellowish, fringe in male partly dark. Legs black except orange base of tibiae; all tarsi black. Male: frons swollen; scutum with black hairs; tergites 2 and 3 with pale hairs at least partly in middle, tergite 3 usually largely covered with pale hairs; tergites with white–grey dusting visible only when viewed obliquely from front. Female: third antennal segment large and round; scutum with short pale hairs of unequal length, intermixed with sparse, somewhat longer black hairs. SIMILAR SPECIES A somewhat odd Cheilosia, therefore not too difficult to identify. Most distinctive character is wide face: below eyes clearly wider than an eye; this, in combination with black legs except orange base of tibiae, distinguishes it from all other Cheilosia except very similar C. morio; for differences with C. morio, see that species. OCCURRENCE A northern and eastern species that recently colonised spruce plantations in the continental range covered by this book. Not known from Great Britain. ECOLOGY Mature spruce plantations. Often to be found on flowering willow. With C. morio, larval biology differs from other Cheilosia: larva inhabits resin outflows on the trunk of spruce, caused by damage or the activities of scolytid beetles. COMMENT Until recently, this species was known as C. morio, but soon-to-be-published research will show that this name actually

belongs to the hairy-faced sister species which until now lacked a widely accepted name. Cheilosia luteicornis is the correct name for the here-described bare-faced species.

Bearded Spruce Blacklet Cheilosia morio IDENTIFICATION 7–10 mm. A slightly smaller relative of

C. luteicornis. Eyes with hairs; face wide; face with hairs, long black hairs in male and less conspicuous pale hairs in female; orbital strip narrow; third antennal segment dark or orange– brown and paler below, but in female often entirely orange or with only upper margin black. Usually, posterior margin of scutellum without bristles in male, with bristles in female; scutum anteriorly with indistinct dusted longitudinal stripes. Legs black except orange base of tibiae, although in male base of fore and hind tibiae usually blackish or obscured reddish; all tarsi black. Male: frons swollen; face with a slight, but distinct dusted bulge on each side, just above facial tubercle; scutum with black hairs; calypter brownish-grey to blackish; abdomen entirely covered with black hairs; tergites with white–grey dusting visible only when viewed obliquely from front. Female: third antennal segment large and round; scutum with short pale hairs of equal length, with only individual black hairs intermixed. SIMILAR SPECIES For differences with Cheilosia other than C. luteicornis, see that species. Very similar to C. luteicornis, main difference being hairs on face in C. morio, but note that hairs can be indistinct and thus easily missed in female. C. luteicornis also differs from C. morio in having face and frons slightly wider, orbital strip narrower; males with abdomen hairs only black instead of with some pale hairs, face with bulges above facial tubercle and base of fore and hind tibiae usually darker; females with shorter equally long pale hairs on scutum with only a few individual black hairs intermixed. OCCURRENCE Distribution not well known because of confusion with C. luteicornis, but in range covered by this book, confirmed from northern Germany. Not known from Great Britain. ECOLOGY Mature spruce plantations. Often found on flowering

willow. COMMENT Until recently this species was mainly referred to as C. morio B or C. scanica, but soon-to-be-published research will show that it actually is the true C. morio.

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da rk spo t

♀

a b d o me n

♂

♀

a b d o me n

b o dy wi th g i nger-red ha i rs

♂

head

♂ l o ng w hi te ha i rs

♀

whi te b ri stl es

♀

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head

3 r d a nte nna l se gm e nt l a rge a nd o ra nge

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Bumblebee Blacklet Cheilosia illustrata IDENTIFICATION 9–11 mm. A handsome hairy bumblebee-like

Cheilosia. Eyes with hairs; face with hairs. Scutum and scutellum with yellow and white hairs and with broad field of black hairs on posterior part of scutum. Wing: with distinct spot in middle. Legs largely black, but with pale parts on tibiae and tarsi. Tergites 1 and 2 with white and yellow hairs, tergite 3 mostly covered with black hairs and tergite 4 with orange–red hairs. SIMILAR SPECIES Owing to unique colour distribution of the long hairs on thorax and abdomen not readily confused with other Cheilosia. Could be mistaken for other bumblebee mimics; hairs on abdomen roughly like in Eriozona syrphoides and Eristalis oestracea, but differs from former by black face and scutellum, and from latter by black scutellum, smaller size and vein R4+5 almost straight, without a dip into cell r4+5. OCCURRENCE Widespread and locally common. ECOLOGY Tallherb grasslands, at the edge of moist broad-leaved forests, road verges but also gardens. Commonly found on umbellifers, seems

to have a strong preference for hogweed. Larva has been found in roots of Parsnip and Common hogweed.

Foxy Blacklet Cheilosia chrysocoma IDENTIFICATION 9–11 mm. A furry Cheilosia mimicking the bee

Andrena fulva. Eyes with hairs; face bare; third antennal segment orange and angled in upper outer corner. Posterior margin of scutellum without bristles. Wing: brownish, with darker centre and dark crossveins r-m and bm-m, although indistinct in fresh specimens. Legs partly pale: femora mostly black but tibiae yellow with at most a black smudge in middle. Body with ginger–red hairs. SIMILAR SPECIES The best discriminating character is the ginger–red ‘fur’ on scutum and abdomen, other Cheilosia with dense body hairs like C. albipila and C. grossa have yellow or orange–yellow hairs; if still in doubt, unlike C. albipila wings dark, third antennal segment with angled upper outer corner, hairs on sides of scutum straight and female with largely black femora; moreover, third antennal segment black in C. grossa. Larger and hairs much denser compared to C. nebulosa. OCCURRENCE Widely recorded but generally rare. ECOLOGY Near damp forests, lush, wet tall-herb grasslands, marshes. Sits low near the ground and regularly visits flowers of, for example, willow, hawthorn and Marsh marigold. Males settle in sunlit places in forest edge or

other sheltered spots, and keep returning to the same spot. Larva probably mines Wild angelica.

Large-horned Blacklet Cheilosia laticornis IDENTIFICATION 8–10 mm. Medium-sized relatively robust species. Upper half of orbital strip and adjacent corners of face with long white hairs; eyes bare; face bare; face wide. Legs partly pale. Sternites dull. Male: third antennal segment blackish above, dark red–orange below; sides of face not parallel, diverging; posterior margin of scutellum without or with thin black bristles. Female: third antennal segment strikingly large, orange with blackish upper margin; posterior margin of scutellum with white bristles; abdomen with silver–grey bands of hairs. SIMILAR SPECIES Unique among Cheilosia covered in this book by possessing long white hairs on upper half of orbital strip, extending onto nearby corners of face. Other notable field characters are wide face and, in female, very large third antennal segment, which is orange below. Like C. proxima and allies, sternites dusted and female abdomen also with silver–grey bands of hairs; however, eyes bare. Differs from other Cheilosia species with bare eyes and partly pale legs by having dusted sternites. OCCURRENCE A handful of strays in the area covered by this book. Not known from Great Britain.

ECOLOGY Tall-herb open areas and tracksides in montane,

southern European broad-leaved forest. Mainly seen on white umbellifers. Larval biology unknown.

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♀

a b d o me n

sc u te l l u m

fore tars us dark

♂

hi nd m a rgi n ye l l o w

♂

♀

head

a b d o me n

♀

hi nd ma rgi n scutel l u m yel l ow

head

♂

ge na so m e ti m e s ye l l o w f a ci a l tube rcl e v e ry w i de

♂

head

♂

thorax lateral

head

♂

upper hi nd corne r o f a nte ri o r a nepi ste rnum ha i re d

♂

head

f a ci a l tube rcl e v e ry w i de

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Heath Blacklet Cheilosia longula IDENTIFICATION 6–9 mm. A slender and dark Cheilosia. Eyes

bare; face bare; facial tubercle not widened, cone-shaped when viewed from above; third antennal segment usually dark, never bright orange; arista with hairs longer than width of arista at base, best assessed with a microscope; posterior margin of scutellum with bristles. Legs partly pale; fore tarsus dark, black in male and at least dark in female. Male: facial tubercle nose-shaped when viewed in profile; scutum with black hairs. Female: third antennal segment dark and not distinctively large; postpronotum dark yellow; posterior part of scutellum and mouth edge usually with yellow markings. SIMILAR SPECIES Owing to bare eyes and partly pale legs, mainly confused with C. pagana, C. scutellata and C. ruffipes. Unlike in C. pagana, fore tarsus and third antennal segment darker and arista with longer hairs. Unlike in C. scutellata and C. ruffipes, facial tubercle less wide and fore tarsus dark. Female like C. mutabilis but that species has frons with longitudinal groove, usually eyes with sparse hairs, tibia darker

but central tarsomeres of fore leg paler and no yellow markings on postpronotum, face and scutellum. OCCURRENCE Widespread but localised, can be common in heathland near forest. ECOLOGY Forests on base-poor soil, particularly in adjacent heathland and moorland. Visits Common heather or yellow composites. Males can be found hovering above mushrooms, usually boletes. One of the three Cheilosia covered in this book in which the larva lives in mushrooms, here, boletes.

Bolete Blacklet Cheilosia scutellata IDENTIFICATION 7–10 mm. Slender medium-sized Cheilosia. Eyes

bare; face bare; facial tubercle very wide, reaching eye margins, semicircular when viewed from above; arista with hairs, hairs longer than width of arista at base, although difficult to assess with a hand lens; third antennal segment usually dark, ranging from dark orange to brown–black. Scutum finely punctate; upper posterior corner of anterior anepisternum bare; posterior margin of scutellum with bristles. Legs partly pale; fore tarsus with basal tarsomeres pale. Female: postpronotum and posterior margin of scutellum almost always yellow. SIMILAR SPECIES Shares bare eyes and partly pale legs with C. longula, C. pagana and C. ruffipes; partly pale fore tarsus and wide facial tubercle distinguishes it from C. longula; longer hairs on arista and wide facial tubercle from C. pagana. With only C. ruffipes, also shares combination of bare eyes and wide facial tubercle but orange third antennal segment distinctive of C. ruffipes, and usually brown, seldom dark orange in C. scutellata. For certain identification also check anterior anepisternum: upper posterior corner bare in C. scutellata, with hairs in C. ruffipes, best judged by using a microscope and

viewing from head towards thorax. OCCURRENCE A widespread species across the whole of Europe, usually common in forests. ECOLOGY In both broad-leaved and coniferous forests and forest edges, and in more open habitats, such as flowery meadows, heathlands, dunes, that are associated with Boletus. Males hover 1–2 metres above the ground at forest edges or in open forest, often in dappled light. Often seen on tall white or yellow umbellifers such as hogweed, Wild angelica and Parsnip. Larva lives in mushrooms, mainly boletes.

Truffle Blacklet Cheilosia ruffipes IDENTIFICATION 7–10 mm. Fairly large and slender Cheilosia. Eyes

bare; face bare; facial tubercle very wide, reaching eye margins, semicircular when viewed from above; arista with hairs, hairs longer than width of arista at base, although difficult to assess with a hand lens; third antennal segment bright orange. Upper posterior corner of anterior anepisternum with hairs; scutum punctate, moderately coarse; posterior margin of scutellum with bristles. Legs partly pale. Female: usually postpronotum and posterior margin of scutellum yellow. SIMILAR SPECIES Shares bare eyes and partly pale legs with C. longula, C. pagana and C. scutellata; partly pale fore tarsus and wide facial tubercle distinguishes it from C. longula; longer hairs on arista and wide facial tubercle from C. pagana; most similar to C. scutellata, sharing very wide facial tubercle, but third antennal segment entirely bright orange (never more than dark orange in C. scutellata) and punctation on scutum coarser; most reliable character hard to judge in the field: anterior anepisternum with hairs in upper posterior corner, bare in C. scutellata.

OCCURRENCE Widespread but localised, often abundant in suitable habitat, a southern species in Europe that appears to be expanding northwards. ECOLOGY Near broad-leaved forests on base-rich soil, calcareous grassland, scrub and woodland rides. Favours tall white and yellow umbellifers especially hogweed, Wild angelica and Parsnip. Larva undescribed, but probably lives in mushrooms, possibly truffles. COMMENT Until recently, mainly known under the name Cheilosia soror.

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ste rni te s 2 – 5 shi ny

♂ ♀

a b d o me n u n d e rsi d e

s c ut um d et ail

♀

♂

head

head

co a rse punctu a ti on

ste rni te s 2 – 5 shi ny

♂

♀

♂

s c ut um d et ail

♂

head

head

fi ne punctu a ti on

f ro ns shi ny

♀

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e re ct ye l l o w ha i rs

sc u tu m

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Black-legged Blacklet Cheilosia nigripes IDENTIFICATION 7–10 mm. Compact blackish Cheilosia with bare

eyes and all-black legs. Facial tubercle pronounced, its upper side sloping; third antennal segment black; orbital strip not widened; eyes bare. Scutum coarsely punctate: space between dots 2–3 times dot diameter; posterior anepisternum shiny; posterior margin of scutellum with black bristles. Wing: black at base. Legs black. Sternite 1 densely dusted, sternites 2–4 shiny. Male: frons shiny; scutum in middle with short and long black hairs; tergite 4 predominantly with black hairs. Female: scutum with short, mainly dark, recumbent to adpressed hairs; wing darkish and with dark-brown veins. SIMILAR SPECIES C. ahenea, C. grisella, C. pubera and C. sahlbergi also have eyes bare and legs black, but they have sternites 2–4 dusted. Most similar to C. antiqua and C. vicina. Not the most stable character, but often facial tubercle less strongly developed than in the those two, upper side not horizontal but sloping. Male: like C. vicina, but frons shiny and posterior anepisternum shiny; like C. antiqua but scutum coarsely punctate and tergite 4 largely covered with black hairs. Female: like C. vicina but posterior anepisternum shiny; like C. antiqua but scutum in middle with adpressed short black hairs, not with erect pale hairs. OCCURRENCE A widespread species over Europe but rather localised in the range covered by this book. When present, often in good numbers. ECOLOGY Glades in forest on base-rich soils, in the forest edge and on adjacent chalk grasslands, in both dry and wet conditions. Visits low flowers such as buttercups. Larval biology unknown.

Primrose Blacklet Cheilosia antiqua IDENTIFICATION 6–9 mm. Compact black Cheilosia with bare

eyes and black legs. Upper side of facial tubercle more or less horizontal when viewed from side; third antennal segment black; eyes bare. Scutum finely punctate: space between dots 5–10 times dot diameter; posterior anepisternum shiny; posterior margin of scutellum with black bristles. Legs black. Sternite 1 thickly dusted, sternites 2–4 shiny. Male: frons shiny; scutum in middle with mainly black hairs of equal length; tergite 4 sometimes widely covered with white hairs. Female: scutum with erect pale hairs. SIMILAR SPECIES C. ahenea, C. grisella, C. pubera and C. sahlbergi also with eyes bare and legs black, but they have sternites 2–4 dusted. Very similar to C. nigripes and C. vicina; female relatively easily distinguished by yellowish erect hairs on scutum, adpressed hairs in other two; male like C. vicina but frons and posterior anepisternum shiny; male like C. nigripes but scutum finely punctate, facial tubercle more pronounced and sometimes large part of tergite 4 with pale hairs. OCCURRENCE Widespread in region covered by this book but very localised. ECOLOGY Old moist broad-leaved forests with abundant primrose. Often settles on low plants in sunny forest clearings and beside tracks in woodland. Often found on Marsh marigold. Larva mines roots of several primrose species, mostly native primrose in the British Isles.

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♂

head

♂

l a rge f a ci a l tube rcl e

sho rt m a i nl y ye l l o w a dpre sse d ha i rs

♂

head

♀

scut u m

sho rt pa l e a nd bl a ck ha i rs a nd l o ng bl a ck ha i rs

fro ns d usted

♂

scutu m

♂

head

♀

head

♂

♂

ab d o men und ers id e

♂

head

w i th sho rt pa l e a nd l o ng bl a ck ha i rs fro ns sh i ny s te rnite s dus te d

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sc u tu m

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Lady’s-mantle Blacklet Cheilosia vicina IDENTIFICATION 6–8 mm. A fairly small black Cheilosia with bare

eyes and entirely black legs. Upper side of facial tubercle more or less horizontal; third antennal segment black. Scutum coarsely punctate: space between dots 2–3 times dot diameter; posterior anepisternum slightly dusted; posterior margin of scutellum with black bristles. Legs black. Sternite 1 thickly dusted, sternites 2–4 shiny. Male: frons dusted; scutum with short pale and dark hairs and long black hairs. Female: scutum with short, pale and dark, adpressed hairs; wing base with brown tint, veins pale brown. SIMILAR SPECIES C. ahenea, C. grisella, C. pubera and C. sahlbergi also with eyes bare and legs black, but they have sternites 2–4 dusted. Part of hard-to-identify trio with C. nigripes and C. antiqua: males differ from other two by more slender build and dusted frons; in both sexes, dusted posterior anepisternum distinguishes them from C. nigripes and C. antiqua; female also differs from C. antiqua in having hairs on scutum of mixed colour and adpressed, instead of pale and erect. OCCURRENCE Largely restricted to northern and upland areas in region covered by this book. ECOLOGY Flowery meadows at the edge of broad-leaved forest, wide forest tracks or forest glades in broad-leaved forest. Flies close to ground; males often settle in sunny open spots on low bushes or herbs. Often visits buttercups. Males seem to defend small territories from low perches. Larva has been found in Lady’s-mantle.

Bistort Blacklet Cheilosia sahlbergi IDENTIFICATION 7–8 mm. A dark Cheilosia with entirely black

legs and bare eyes. Face bare; orbital strip very wide, wider than half the width of third antennal segment; third antennal segment entirely black or dark red below. Posterior margin of scutellum with black bristles; scutum shiny and finely punctate; scutum with dense short yellow hairs, with longer black hairs intermixed. Legs black. All sternites dusted, dull. Male: frons shiny or only slightly dusted. Female: frons above antennae slightly dusted; face around facial tubercle shiny. SIMILAR SPECIES Shares bare eyes and black legs with C. antiqua, C. nigripes and C. vicina, but these species with sternites 2–4 shiny. Much like C. ahenea, C. grisella and C. pubera; both sexes distinguished from them by hairs on scutum: dense, yellow, with longer black hairs intermixed; moreover, orbital strip wide, clearly wider than in C. ahenea and C. pubera. OCCURRENCE A northern species that is largely restricted to mountain areas in Central Europe, in region covered by this book restricted to the Scottish Highlands. ECOLOGY Near streams in unimproved, thinly vegetated, non-calcareous subalpine grassland. Often visits flowers of buttercup and sometimes Common tormentil. Larva undescribed, but found on Alpine bistort.

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head

f ro ns duste d

f a ce duste d

♀

♂

s c ut um

head

d ense yel l ow h a i rs dusted

♂

abdomen unde rsi d e

♀

♂

a b d o me n

head

♂

f ro ns a nd f a ci a l tube rcl e shi ny

uppe r hi nd co rne r o f a nte ri o r a ne pi ste rnum ha i re d

th o ra x l a te ra l

♀

a b d o me n

♂ ♂

bo th pa l e a nd da rk ha i rs

♂

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f ro ns a nd f a ce duste d

scutum

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Water Avens Blacklet Cheilosia pubera IDENTIFICATION 6–7 mm. A fairly small brown–green Cheilosia. Eyes bare; face bare; face around facial tubercle lightly dusted: dusting above facial tubercle fades gradually into dusted band below antennae. Anterior anepisternum bare in upper posterior corner; posterior margin of scutellum with black bristles; scutum lightly dusted and finely punctate; scutum with dense erect yellow hairs. Legs black. All sternites dusted, dull. Male: frons dusted. Female: third antennal segment usually slightly reddish brown below; frons behind lunule shiny or lightly dusted; posterior margin of scutellum with 4–6 black bristles. SIMILAR SPECIES Shares bare eyes and black legs with C. antiqua, C. nigripes and C. vicina, but these species with sternites 2–4 shiny. Much like C. ahenea, C. grisella and C. sahlbergi, but male with exclusively erect yellow hairs on scutum, only shared with C. ahenea, but frons and face more dusted, anterior anepisternum bare in upper posterior corner and body more bronze coloured. Female distinguished from the other three species with difficulty,

but orbital strip narrower and face more dusted compared to C. sahlbergi; face more dusted than in C. ahenea and compared to C. grisella scutellum with fewer bristles on posterior margin, third antennal segment often slightly paler below and orbital strip slightly narrower; females cannot always be distinguished from C. grisella with certainty. OCCURRENCE A widespread but very localised species, can be abundant in suitable habitat. ECOLOGY A species of peaty wetlands, stream margins, mire and open carr where the foodplant occurs, usually near rather base-rich water. Usually flies low and sits on leaves of plants near water. Visits flowers of, for example, buttercups and Marsh marigold. Larva mines Water avens.

Brassy Blacklet Cheilosia ahenea IDENTIFICATION 6–9 mm. A shiny black species. Eyes bare; face bare; face around facial tubercle shiny, distinctly contrasting with grey band of dusting directly below antennae; frons shiny. Anterior anepisternum with hairs in upper posterior corner; posterior margin of scutellum usually with but sometimes without bristles; scutum with erect yellow hairs; scutum shiny and coarsely punctate. Legs entirely black. All sternites dusted, dull. SIMILAR SPECIES Shares bare eyes and black legs with C. antiqua, C. nigripes and C. vicina, but that trio has sternites 2–4 shiny. Much like C. pubera, C. grisella and C. sahlbergi, but scutum coarsely punctate, thus space between dots equals 2–3 times instead of 5–10 times dot diameter. Male: shares scutum covered entirely with yellow hairs with C. pubera, but frons and face shinier, anterior anepisternum with hairs in upper posterior corner and body with black rather than bronze sheen. Female: unlike C. sahlbergi scutum hairs entirely yellow and unlike C. pubera and C. grisella, face shiny around facial tubercle. OCCURRENCE A disjunct European population in Ireland and off Scotland and some isolated populations in Central Europe are the only ones in

region covered by this book. ECOLOGY Permanent, unimproved grassland, both calcareous and non-calcareous subalpine pasture in Central European mountains. In Ireland and Scotland, at sea level in calcareous machair grassland. Flies low near the ground and suns on bare ground or on stones, male hovers up to several metres above the ground. Larval biology unknown.

Dusted Blacklet Cheilosia grisella IDENTIFICATION 6–8 mm. A dark brown–grey species. Eyes bare;

face bare; third antennal segment black. Posterior margin of scutellum either with or without bristles. Scutum finely punctate and distinctly dusted. Legs entirely black. Sternites dusted. Male: frons clearly dusted; hairs on scutum long and erect with a mix of dark and pale hairs. Female: frons above lunule with dust spots along eye margin, often connected to form a dusted band; face around facial tubercle lightly dusted; hairs on scutum erect and yellow; posterior margin of scutellum with two bristles or bristles absent. SIMILAR SPECIES Shares bare eyes and black legs with C. antiqua, C. nigripes and C. vicina, but that trio has sternites 2–4 shiny. Most similar to C. pubera, C. ahenea and C. sahlbergi. Male: mix of pale and dark hairs on scutum, like C. sahlbergi, but scutum dusted and frons thickly dusted. Female: like C. sahlbergi, but orbital strip narrower and face duller; like C. ahenea but face thinly dusted and scutum finely punctate; much like C. pubera but posterior margin of scutellum without or with only two bristles instead of 4–6, moreover third antennal

segment usually blacker and orbital strip slightly wider; females are so similar to C. pubera that distinguishing single females is problematic; it is better try to collect males as well, which are easier to identify. OCCURRENCE A species of Central European mountains that occurs very locally at the eastern range covered by this book (east Belgium, western Germany). Not known from Great Britain. ECOLOGY Flight period May–July. Unimproved montane/subalpine grassland on calcareous and non-calcareous sites. Larval biology unknown.

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a b d o me n

♂

♂

head

dark s pot

f a ce pro trudi ng do w nwa rds

♀

sc u te l l u m

w i th sho rt ha i rs

♂

♀

head

l i ghtl y duste d

3 r d ante nna l segm e nt pa l e

h a i rs o n fa ce som eti mes d i ffi cul t to see o rb i ta l stri p wi d e

fa ce and fro ns n a rro w

♂

o rbi ta l stri p w i de

face

♀

sc u te l l u m

w i th l o ng ha i rs

♂

abdome n e longate d f a ce a nd f ro ns w i de

♂

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Houseleek Blacklet Cheilosia caerulescens IDENTIFICATION 7–11 mm. Medium-sized Cheilosia with white body hairs and spot on wing. Eyes bare; face bare; face distinctively protruding downwards; third antennal segment almost round, red–brown to black; arista almost bare. Scutum and abdomen with blue–grey metallic sheen; body hairs strikingly light grey to white, sometimes with a yellowish tinge. Wing: with dark spot in middle, sometimes indistinct. Legs partly pale. SIMILAR SPECIES Quite easily recognised, even in the field: dark spot on wing and white body hairs stand out; in combination with elongated face, bare eyes and partly pale legs, diagnostic. OCCURRENCE Colonisation of North-west Europe started in the second half of the 1990s and species is still spreading, including in Great Britain where it was first found in 2006. Now widespread in most of the range covered in this book, but in low numbers. ECOLOGY In its native range, a species of alpine grassland and rocky slopes at high altitudes, but now also at low altitudes in ornamental gardens, green roofs or graveyards with houseleeks. Larva mines leaves of houseleeks.

Hawkbit Blacklet Cheilosia latifrons IDENTIFICATION 7–9 mm. A fairly small to medium-sized brownish

Cheilosia. Eyes with hairs in male, bare or with sparse hairs in female; face with hairs but hairs may be absent in female; orbital strip very wide; third antennal segment usually orange–brown with dark upper margin, sometimes entirely brown–black. Posterior margin of scutellum without bristles. Legs brownish but tibiae and tarsi with extensive yellow parts. Sternites with thin dusting. Male: frons moderately shiny with thin dusting, dusting less dense than on face; eyes meeting for a length longer than length of ocellar triangle; tergites 2 and 3 about twice as wide as long; tergite 3 with pair of approximately square grey spots. Female: hairs on scutellum short, adpressed, about half as long as the width of hind tibia; base of hind femur black or with minimum amount of orange. SIMILAR SPECIES A distinctive species: combination of face with hairs (may be absent in females), partly pale legs, posterior margin of scutellum without bristles and very wide orbital strip shared only with very similar C. griseiventris. Distinguished with difficulty from C. griseiventris but is smaller, a bit stockier, with wider abdomen and third antennal segment

paler; male with face and frons narrower, eyes meeting over a longer distance and frons less dusted; female sometimes not identified with certainty but scutellum with short adpressed hairs and base of hind femur black or nearly so. OCCURRENCE A widespread species in Europe but usually in low numbers. ECOLOGY A variety of open habitats, including pasture and grassy flood banks, dune grasslands, at the edge of heathlands, calcareous grasslands, brownfield lands and along forest tracks with lots of hawkbit, the host plants of C. latifrons.

Sow-thistle Blacklet Cheilosia griseiventris IDENTIFICATION 8–10 mm. A medium-sized, fairly elongated

Cheilosia. Eyes with hairs in male, bare or with sparse hairs in female; face with hairs; orbital strip very wide; third antennal segment dark. Posterior margin of scutellum without bristles. Legs partly pale, tibiae pale at both ends. Male: both frons and face densely dusted, without contrast between them; face and frons wide; eyes meeting for a length equal to or less than length of ocellar triangle; tergites 2 and 3 less than twice as wide as long; grey dust spots on tergite 3 triangular. Female: face dusted; hairs on scutellum long, at least as long as width of hind tibia; base of hind femur yellow for one-tenth to a quarter its length. SIMILAR SPECIES Rather similar to C. latifrons, for differences with other Cheilosia see C. latifrons. Like C. latifrons but larger, abdomen more elongated, hairs on scutum and abdomen longer, third antennal segment darker and face and frons with denser dusting; male with both frons and face densely dusted without contrast between the two, frons and face wider, therefore eyes meeting over a shorter distance, tergites 2 and 3 narrower and

grey spots on side margin of tergite 3 more triangular; females distinguished from C. latifrons with difficulty, but have hairs on scutellum longer and base of hind femur yellow. OCCURRENCE A southern species that appears to be expanding northwards in Belgium. ECOLOGY More in ruderal terrains and more on base-rich soils compared to C. latifrons: arable margins, roadsides, old quarries, trampled grasslands and dykes. Adults are mostly seen feeding on low flowers such as dandelions, autumn generation often on ivy. Males keep territories from a low perch. Host plant unknown but possibly sow-thistles.

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fa ci a l tubercle no t wi de

♂

♂

head

♂

head

♀

head

ce ntral tars ome re s pal e

3 r d a nte nna l se gm e nt o ra nge a nd v e ry bi g

♂

head

♂ large, all black s pe cie s

s c ut ellum

♀

bri stl es l ong

head

♂

sc u te l l u m

♀

sc u te l l u m

bri stl e s sho rt bas e ti bi a p a l e

♂

♀

bri stl e s v e ry sho rt

head a ri sta sho rt

fa ce h a i red

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a n te n n a

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Parsley Blacklet Cheilosia pagana IDENTIFICATION 5–9 mm. A small slender Cheilosia with orange

antennae. Eyes bare; face bare; facial tubercle not widened, coneshaped when viewed from above; third antennal segment orange; arista with very short hairs, hairs shorter than width of arista at base. Posterior margin of scutellum with bristles; scutellum and postpronotum black. Wing: transparent. Legs extensively pale; middle segments of fore tarsus pale. Sternites shiny. Spring generation tends to be a little larger and hairier than summer generation, with scutum hairs often entirely pale. Female: third antennal segment very large. SIMILAR SPECIES Females stand out in the field owing to very large bright-orange third antennal segment. Shares bare eyes and partly pale legs with C. longula, C. scutellata and C. ruffipes; differs from first by having orange antennae, partly pale fore tarsus and short hairs on arista; from latter two by facial tubercle not being widened, arista with short hairs; females differ from all three species by having scutellum and postpronotum black. OCCURRENCE A very common and often

abundant Cheilosia in North-west Europe. ECOLOGY In various habitats where the host plants occur: forest edges, flower-rich meadows, hedges and gardens. Sits on leaves of plants and bushes and visits low flowers of various plant species, spring generation common on willows, dandelions and Lesser celandine. Spring males often bask on tree trunks. Males hover up to several metres above the ground in sunlit, sheltered spots. Larva mines umbellifers such as Cow parsley, Wild angelica and hogweed. When held in the hand, produces a characteristic ‘stuttering’ buzz.

Figwort Blacklet Cheilosia variabilis IDENTIFICATION 9–12 mm. A large, elongated and long-winged

Cheilosia recognised fairly easily. Eyes with hairs; face with hairs; arista long: over twice as long as length of third antennal segment. Posterior margin of scutellum with long bristles, bristles at least as long as scutellum itself. Wing: long and elongated, when closed protruding far beyond abdomen; wings slightly dark, brown–black, especially in female. Legs black. Black body sometimes with blue sheen in sunlight. SIMILAR SPECIES Stands out in the field by combination of large size, long wings and elongated appearance, black legs and hairs on face. Only Cheilosia in area covered by this book with combination of entirely black legs and face with hairs. Most resembles C. lasiopa but that species is more compact, has shorter wings, has base of tibiae yellow and has shorter arista and bristles on posterior margin of scutellum. OCCURRENCE Widespread over the range covered in this book, frequent near forest. ECOLOGY Woodland that is not too dry and where host plants occur. Males hold territories in characteristic posture, with half-opened wings, from a low perch on sunlit leaves in the forest edge. Females sit on

leaves and visit white umbellifers. Larva mines roots of Common Figwort and Water figwort.

Plantain Blacklet Cheilosia lasiopa IDENTIFICATION 9–10 mm. Dark, fairly broad Cheilosia with hairs

on face. Eyes with hairs; face with hairs; third antennal segment dark; arista short: about twice as long as length of third antennal segment. Posterior margin of scutellum with black bristles; especially in female these bristles very short, much shorter than length of scutellum, in male usually just shorter than scutellum. Tip of tibia black; base of fore and mid tibiae yellow; base of hind tibia narrowly yellow or black. Sternites dusted, sometimes only weakly so. Female: abdomen with quite indistinct oblique patches of longer silver–grey hairs. SIMILAR SPECIES Hairs on face distinguish this species from many other Cheilosia. Differs from Cheilosia with facial hairs by having short bristles on posterior margin of scutellum and fore and mid tibiae usually with only base yellow, in other species either base and tip yellow or tibia entirely black. Similar to C. variabilis; for additional differences, see that species. OCCURRENCE Rather scarce and local on the North-west European continent, but widespread and locally frequent in Great Britain. ECOLOGY Meadows with scrub, woodland rides, heathland

edge, coastal dunes. Often found on Cow parsley and other white umbellifers. Larva mines Ribwort plantain but there is also a sighting of egg-laying on Greater plantain.

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♀ ♂

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upperp a rt occi p ut shi ny

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a b d o me n

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Parsnip Blacklet Cheilosia barbata IDENTIFICATION 7–9 mm. A hairy, quite slender Cheilosia. Eyes

with hairs; face with hairs; third antennal segment orange–red below, upper margin usually dark; arista with hairs, hairs longer than width of arista; arista over three times longer than third antennal segment; face quite flat with poorly developed facial tubercle. Posterior margin of scutellum with bristles as long as or longer than scutellum; upper and lower hair patches on katepisternum connected. Tibiae pale at base and tip. Male: frons not swollen; tergites without dust spots; sternites weakly to quite thickly dusted; central part of tergite 4 with semi-adpressed hairs; genitalia: surstylus almost twice as long as wide, with large distinct field of microtrichia on apical outer part. Female: third antennal segment large, rounded; upperpart occiput shiny; scutum with short golden-yellow semi-adpressed hairs; sternites shiny or very lightly dusted. SIMILAR SPECIES Shares combination of hairs on face, partly pale legs and posterior margin of scutellum with bristles with C. lasiopa, C. frontalis and C. vulpina. C. lasiopa

has darker legs, only base of tibiae yellow and has shorter bristles on posterior margin of scutellum. Like C. frontalis but larger, flies later in the season, arista with longer hairs, hair patches on katepisternum connected, male frons not inflated and abdomen without dust spots. For differences with C. vulpina, see that species. OCCURRENCE This is a common summer species in woodlands in the southern part of the region covered by this book, yet comparatively little is known about its ecology. ECOLOGY Forest edge, road verges, tall-herb forest glades. In Great Britain, chalk and limestone tall grasslands and associated woodland rides or clearings. Males hover above forest tracks and along forest edges. Both sexes visit flowers, mainly those of Common hogweed and Wild parsnip. Larval biology unknown but probably associated with Wild parsnip.

Stocky Blacklet Cheilosia vulpina IDENTIFICATION 8–11 mm. Quite large stocky black or somewhatbrownish species. Eyes with hairs; face with hairs; third antennal segment brown to black. Posterior margin of scutellum with bristles longer than scutellum. Legs partly pale, tibiae pale at base and tip. Sternites thickly dusted. Spring generation larger and with longer hairs than summer generation. Male: facial tubercle well developed; tergite 4 with erect hairs; genitalia: surstylus only a little longer than wide, almost squarish, without large distinct field of microtrichia on apical outer part. Female: occiput dusted; tergites 2–4 with oblique patches of longer silver–grey hairs, resembling a large, strongly marked C. proxima. SIMILAR SPECIES Shares combination of face with hairs, partly pale legs and posterior margin of scutellum with bristles with C. lasiopa, C. frontalis and C. barbata. Bristles on posterior margin of scutellum longer and legs more extensively yellow than in C. lasiopa. Compared to C. frontalis and C. barbata, larger, facial tubercle more developed and antennae darker; in female, most unambiguous difference is in occiput: entirely dusted in C. vulpina, upper part shiny in C. frontalis and C. barbata; moreover, in

female, oblique patches of longer silver–grey hairs on tergites 2–4 more distinct (useful feature in the field) and male lacks dust spots on abdomen and inflated frons of C. frontalis, and compared to C. barbata hairs on tergite 4 erect and surstylus wider, without field of microtrichia on apical outer part. OCCURRENCE Chiefly a southern species in region covered by this book, but expanding northwards on the continent. ECOLOGY Forest glades and edges and tall-herb grasslands, especially on base-rich soils. Frequents tall and white umbellifers. Larva mines thistles, but in region covered by this book probably mainly burdock species.

Kingcup Blacklet Cheilosia frontalis IDENTIFICATION 5–9 mm. A small grey–black Cheilosia. Eyes

with hairs; face with hairs, although often sparse in female; third antennal segment largely orange; arista almost bare; arista over three times longer than third antennal segment. Upper and lower hair patches on katepisternum separated; posterior margin of scutellum with bristles as long as or longer than scutellum. Tibiae extensively pale at base, only narrowly pale at tip. Sternites dusted. Male: frons swollen; tergites with distinct dust spots, especially striking when viewed from above at an oblique angle; hairs on abdomen pale grey. Female: third antennal segment small and round; upper part of occiput shiny; scutum with erect pale hairs. SIMILAR SPECIES Owing to hairs on face, bristles on posterior margin of scutellum and partly pale legs, like C. lasiopa, C. vulpina and C. barbata. Upper and lower hair patches on katepisternum separated, connected in other three species; moreover, smaller and slenderer. Bristles on posterior margin of scutellum longer and legs more extensively yellow than in C. lasiopa. Much smaller, upper part of occiput shiny and third antennal segment paler compared

to C. vulpina. Like C. barbata, but arista with shorter hairs, in female scutum with erect hairs and in male frons more swollen and abdomen with dust spots. OCCURRENCE Mountainous parts of Central and North-west Europe including Belgium, but in northern Netherlands and Denmark at sea level. Not known from Great Britain. ECOLOGY Marshy wet areas with Marsh marigold along brooks and small streams. For some reason absent in lowland alluvial areas of large rivers with extensive stands of Marsh marigold, at least in region covered by this book. Frequents willow catkins. Larval biology unknown, but female has been observed egg-laying on Marsh marigold.

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w i ng ba se ye l l o w

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♂

fo re t ars us

♂

ta rso m ere 5 recta ngul a r

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g e n i ta l i a

a b d o me n

♂ w i ng ba se ye l l o w

ta rsom ere 5 na rro wi ng

♂

surstyl us na rro w, ke e l l o w e r, w i tho ut m i cro tri chi a

♂

fo re t ars us

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g e n i ta l i a

♀

l egs b l a ck

w i ng ba se ye l l o w

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p roj ecti on

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Buttercup Blacklet Cheilosia albitarsis IDENTIFICATION 7–10 mm. A familiar, dark blackish Cheilosia with mainly black legs. Eyes with hairs in male, bare in female; face bare. Wing: base dark brown in male, yellow in female. Legs black, except middle tarsomeres of fore and mid tarsi, usually less obvious on mid tarsus; this is distinct in male, but in females colour difference can be minimal. Male: tarsomere 5 of fore tarsus rectangular; all hairs on tergite 4 erect; genitalia: surstylus c. 1.5 times longer than wide and with distinctive keel covered with microtrichia. SIMILAR SPECIES Very similar to much rarer C. ranunculi; females cannot be distinguished; for differences, see that species. Like C. impressa but larger and middle segments of fore tarsus pale. Male: easily distinguished from all other Cheilosia species except C. ranunculi by combination of all-black legs except pale middle tarsomeres of fore tarsus, eyes with hairs and face bare. Female: can be confused with several other Cheilosia with black legs and bare eyes; pale middle tarsomeres of fore tarsus is best distinguishing character, but contrast with

remaining tarsomeres can be minimal or even absent, if so, yellow wing base is useful character. OCCURRENCE A widespread, frequent and abundant Cheilosia. ECOLOGY Damp pastures, woodland rides and gardens with Creeping buttercup. Males usually sit with several other individuals on leaves in the forest edge, and keep returning to them after short flights. Larva mines the roots of Creeping buttercup.

Bulbous Buttercup Blacklet Cheilosia ranunculi IDENTIFICATION 7–10 mm. A lookalike of C. albitarsis. Eyes

with hairs in male, bare in female; face bare. Wing: base yellow. Legs black, except middle tarsomeres of fore and mid tarsi, usually less obvious on mid tarsus; this is distinct in male, but in females colour difference can be minimal. Male: tarsomere 5 of fore tarsus wider at base and narrowing towards tip; posterior margin of tergite 4 with adpressed hairs; genitalia: surstylus about twice as long as wide and with weak keel without microtrichia. SIMILAR SPECIES For differences with other Cheilosia species except C. albitarsis, see that species. Very similar to C. albitarsis, female cannot be distinguished. In male, wing base is a useful first indication in the field: yellow in C. ranunculi, brownish in C. albitarsis. However, certain identification is possible only after checking the following microscopic characters: tarsomere 5 of fore tarsus wider at base and narrowing towards tip, versus rectangular at C. albitarsis; posterior margin of tergite 4 with adpressed hairs instead of erect hairs; genitalia: surstylus about twice as long as wide instead of 1.5 times longer than wide, and with indistinct keel without microtrichia instead of distinctive keel

covered with microtrichia. OCCURRENCE Shows a strong affinity to grasslands with Bulbous buttercup and can be locally abundant there. ECOLOGY Well-drained permanent pasture and grasslands on neutral to base-rich soils but the decisive condition is the presence of Bulbous buttercup. Adults mainly found on Bulbous buttercup. Larva probably mines Bulbous buttercup.

Yellow-winged Blacklet Cheilosia impressa IDENTIFICATION 6–8 mm. Small black Cheilosia with short

abdomen. Eyes with hairs, sometimes only sparse in female; face bare; third antennal segment entirely black or dark red below. Posterior margin of scutellum with bristles. Body black with bluish sheen. Wing: base distinctly yellow; wings long relative to abdomen. Legs entirely black; unique among Cheilosia covered in this book in possessing a projection at base of outer sides of fore coxae. Male: scutum with erect, short and long black hairs. Female: scutum with short adpressed black and yellow hairs. SIMILAR SPECIES Identification quite straightforward for a Cheilosia. Combination of small size, eyes with hairs, all-black legs and yellow base of wing diagnostic. In the field, could be mistaken for a Psilota, but distinguished by face with orbital strip and facial tubercle, wings with false vein and usually flies later in the season. C. albitarsis and C. ranunculi can have yellow wing base as well (especially females) but they are bigger, have central tarsomeres of fore tarsus pale and females with bare eyes. OCCURRENCE A widespread and fairly abundant species in suitable

habitat, it shows intriguing spatial variation in number of broods: one (summer) in northern Belgium and the Netherlands, but two in many other areas. ECOLOGY Wet broad-leaved forests, riparian forests, wet lush tall-herb grasslands in the vicinity of woodland. Frequently visits white umbellifers such as hogweed and angelica. Males hover usually 2–5 metres above the ground. Host plants of the larva are Greater burdock and Hemp-agrimony.

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centra l ta rso m eres pa l e

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ant enna

3 r d ante n na l seg m ent brown- bla ck

♂

♀

head

head

♀

a b d o me n

♂

w i de b l a ck ri ng

♂

ye llow bri stl es

h i n d f e mu r

bri stl e -l i ke ha i rs ha i rs o n eye l o ng

ha i rs o n e ye l o ng

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Fragile Blacklet Cheilosia mutabilis IDENTIFICATION 5–8 mm. A small slender inconspicuous black

Cheilosia. Face bare; facial tubercle not widened; third antennal segment brown–black, sometimes a little dark orange below, but never bright orange; third antennal segment 1.5 times as long as wide; arista with hairs, hairs as long as or longer than diameter of arista at base. Posterior margin of scutellum with bristles. Wing: slightly dark, caused by dense covering of microtrichia. Legs black with only little orange: hind leg often entirely black, but fore and mid tibiae with (sometimes very narrow) orange base and tip, and fore tarsus with central three tarsomeres paler; claws dark, basal half slightly paler than apical half. Sternites shiny. Male: eyes with hairs; hairs largely pale. Female: eyes with hairs, hairs sparse or absent; postpronotum and scutellum black. SIMILAR SPECIES Dark legs with above-described colour distribution very useful in identification: legs paler than species with black legs, but darker than most species with partly pale legs. Like C. urbana and C. psilophthalma, but hind leg darker, arista with longer hairs and female with less shiny abdomen, with black instead of golden shine and hairs on eyes sparser and slightly shorter. Male: relatively dark legs reminiscent of C. carbonaria and C. cynocephala, but smaller, more elongated, arista with longer hairs, third antennal segment 1.5 times longer than wide instead of round, wing usually more transparent, facial tubercle and face less distinctly protruding and hind tibia usually entirely dark. Female: can be confused with C. pagana when eyes bare but legs are darker and third antennal segment smaller, not bright orange; more like C. longula but postpronotum and scutellum black, tibiae more extensively black and fore tarsus with central tarsomeres

pale; when eyes have hairs, like C. semifasciata, but hairs on eyes sparser and shorter, and central tarsomeres of fore leg pale instead of black. OCCURRENCE A species that flies mainly during the June dip of syrphid diversity and therefore may be overlooked. ECOLOGY Forest glades and edges of well-drained forests, mainly on base-poor soils; also coastal dunes in western Great Britain. Males sit on leaves in forest edge with wings half-open, like a small version of C. variabilis. Visits flowers of, for example, umbellifers. Larva has been found in the above-ground parts of Mouse-ear hawkweed but possibly also mines other hawkweeds.

Wood Blacklet Cheilosia lenis IDENTIFICATION 9–12 mm. A fairly large and elongated Cheilosia.

Eyes with strikingly long hairs, hairs dark in male, pale in female; face bare; facial tubercle in profile often somewhat angular, not smoothly rounded; third antennal segment orange. Posterior margin of scutellum with bristles that are often yellow; upper and lower hair patches on katepisternum connected. Legs partly pale; hind tibia with distinct wide black ring. Sternites shiny. Male: frons slightly swollen, shiny; hind tibia below with black bristle-like hairs. Female: hind tibia below without or with only a few black bristle-like hairs; abdomen with bronze sheen. SIMILAR SPECIES Easily recognisable by long hairs on eyes, even longer than hairs on orbital strip; in all similar Cheilosia species, hairs on eyes shorter (compare per sex, hairs in females shorter). Unlike in, for example, C. bergenstammi, C. fraterna, C. urbana and C. psilophthalma, upper and lower hair patches on katepisternum connected. Bristles on posterior margin of scutellum often yellow or sometimes absent, but differs from species without bristles on scutellum posterior margin by combination of long hairs on eyes, orange third antennal segment, frons undusted and black ring on hind tibia. Like C. chloris but arista black, frons more inflated, hairs on eyes longer and hair patches on katepisternum connected. Black ring on hind tibia covers over half of tibia length, differentiating it from several other similar Cheilosia. OCCURRENCE A species of Central European low mountain ranges, occurring in the south and east of the range covered by this book. Not known from Great Britain. ECOLOGY Damp forests, clearings, forest edges, with Wood ragwort. Often rests low on vegetation. Males hover in forest glades or at forest edge, often in groups, up to 3 metres above the ground. Larva mines Wood ragwort. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 2 4 7

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a b d o me n

♂

ant enna

♂

3 r d a n ten na l seg m ent bl a ck

♂

head

head

♂ 3 r d a nte nna l se gm e nt o ra nge

♀ f e m o ra o ra nge

♀

a b d o me n

♂

tibia yel l ow

f ro ns w i th ye l l o w ha i rs

♂

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Greater Spring Blacklet Cheilosia grossa IDENTIFICATION 11–12 mm. A large and furry spring Cheilosia.

Eyes with hairs; face bare; third antennal segment black. Posterior margin of scutellum without bristles. Legs partly pale; femora largely black, tibiae yellow with dark smudges or a small dark ring. Abdomen with ginger–brown hairs, but tip of abdomen usually with black hairs. SIMILAR SPECIES Several other Cheilosia share the combination of partly pale legs, eyes with hairs and posterior scutellum margin without bristles but C. grossa is only one with a black third antennal segment. Often flies with C. albipila but C. grossa is slightly larger, has third antennal segment black, no blue sheen on abdomen, tip of abdomen usually with black hairs and female with largely black instead of entirely orange femora. Rather big, could be mistaken for C. himantopus but distinguished by having hairs on lower part of eyes and third antennal segment black. OCCURRENCE Overlapping with C. albipila in habitat and distribution, but abundance highly variable among sites for reasons not fully understood. An early-spring species that has

usually stopped flying by mid spring. ECOLOGY Forest edge, along forest tracks or forest glades in wet forests, near willows in pastures and rough abandoned grassland and revegetating brownfield lands. Males hover 2–4 metres above the ground. Frequently visits flowering willows and Blackthorn. Larva mines thistles, mostly Spear thistle but perhaps other species including Marsh thistle to a lesser extent.

Lesser Spring Blacklet Cheilosia albipila IDENTIFICATION 8–12 mm. A large and hairy spring Cheilosia.

Eyes with hairs; face bare; third antennal segment orange; arista black. Posterior margin of scutellum without bristles; hairs on anterior anepisternum with wavy tip. Legs extensively pale; hind femur mostly black in male, entirely orange in female, tibiae yellow. Abdomen with orange–yellow or sometimes yellow–grey hairs. Especially male gives a bicoloured impression: scutum bronze–green, abdomen with blue–purple sheen. Male: frons shiny; hind femur below with several hairs longer than diameter of femur. SIMILAR SPECIES Female: easily distinguished from all other Cheilosia except C. flavipes by having entirely orange femora; female differs from C. flavipes by eyes with dense hairs, scutum and abdomen with long hairs and third antennal segment wider than orbital strip. Male: like C. grossa but slightly smaller, without black hairs on abdomen and third antennal segment orange instead of black; like C. himantopus but smaller and eyes with hairs on lower half; like C. chrysocoma but body hairs not fox-red but yellow–orange, wing transparent and upper outer corner of third antennal segment not angled; like C. nebulosa but larger,

without dark wings, arista black, face narrower and frons shiny.

OCCURRENCE A widespread and frequent early-spring Cheilosia. ECOLOGY At forest edge, forest glades and along wide forest

tracks in wet forests, over wet pastures and marshes. Frequently visits early-flowering bushes such as Blackthorn and willow. Males often hover, from 1.5 to several metres above the ground, in sunny sheltered spots along forest edge, hedges or bushes. Larva mines thistles, especially Marsh thistle.

Yellow-legged Blacklet Cheilosia flavipes IDENTIFICATION 7–13 mm. Fairly large and slender Cheilosia

with short hairs. Face bare; eyes bare in female, with white hairs in male; third antennal segment orange; orbital strip distinctly wide. Hair patches on upper and lower part of katepisternum not connected; posterior margin of scutellum without bristles. Legs largely orange; hind femur below without black bristle-like hairs. Abdomen elongated; sternites with thin dusting. Male: frons with yellow hairs; tibiae yellow, femora with at least dark base and black smudge but sometimes largely dark with orange tip. Female: wings yellowish with yellow–brown veins; legs almost entirely yellow, only apical tarsomeres black and femora sometimes with black smudge; abdomen usually as long as or longer than wings. SIMILAR SPECIES Male: stands out owing to short yellow hairs and narrow elongated abdomen, further distinguished by combination of eyes with hairs, wide orbital strips, dusted sternites, yellow hind tibia, hind femur without black bristle-like hairs and posterior margin of scutellum without bristles; like C. nebulosa and C. albipila, but sternites dusted; like C. canicularis,

C. himantopus and C. orthotricha, but smaller; like C. chloris but hind femur without black bristle-like hairs, abdomen more narrow and elongated, and frons with yellow hairs. Female: shares entirely yellow femora only with C. albipila, but that species has eyes with dense hairs. OCCURRENCE At latitudes covered in this book, a species of low mountain ranges on the continent, scarce. Not known from Great Britain. ECOLOGY Woodland rides, along forest edge, forest glades. Visits mainly low-growing flowers. Egg-laying has been observed on dandelions and Creeping thistle; larva has been found in dandelions.

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♂

a b d o me n

thi n w hi te ha i rs

ha i rs w i th wa v y ti p

th o ra x l a te ra l

ant enna

a ri sta a l most ba re

♂

head

♀

♂

a b d o me n

de nse go l de n ha i rs

ant enna

scutellum

♂

di sti n ctl y ha i red wi th o ut bri stl e s

♀

head

a b d o me n

♂

th o ra x l a te ra l ant enna ye l l o w

ha i rs w i tho ut wa v y ti p

hind ti b i a a ri sta a l most ba re

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Spring Butterbur Blacklet Cheilosia himantopus IDENTIFICATION 13–15 mm. A very large Cheilosia, forming a trio

with equally large C. canicularis and C. orthotricha. Upper half of eyes with hairs, lower half bare; face bare and lightly dusted; third antennal segment orange; hairs on arista about half as long as diameter of arista. Hairs on sides of thorax with wavy tip; posterior margin of scutellum without bristles. Legs partly pale but femora largely black; hind tibia usually with distinct dark ring. Male: fore tarsus with tarsomere 5 sometimes dark. Female: posterior margin of tergite 3 with incomplete band of thinly distributed adpressed hairs; posterior third of tergite 4 with scattered, semi-adpressed hairs; ground colour of abdomen blue– black. SIMILAR SPECIES Large size distinctive in the field. Shares combination of large size, posterior margin of scutellum without bristles and only upper part of eyes with hairs with C. canicularis and some C. orthotricha; very similar to C. canicularis, but flies in spring instead of summer, overlapping very little; for morphological differences, see that species; like C. orthotricha, but that species

has tip of hairs on posterior anepisternum straight, face shiny, outer tarsomere of fore leg black and usually only lower third instead of lower half of eyes bare. OCCURRENCE Widespread but localised. C. canicularis and C. himantopus often share the same stand of Butterbur, but alternate throughout the year. Not known from Great Britain. ECOLOGY Riparian habitats, roadsides, floodplains intermixed with some forest or scrub, in the presence of Butterbur. A fairly mobile species, can be found far away from the host plant. Visits flowers of, in particular, yellow composites. Larva mines the stem of Butterbur.

Summer Butterbur Blacklet Cheilosia canicularis IDENTIFICATION 13–15 mm. A very large Cheilosia. Upper half

of eyes with hairs, lower half bare; face bare and slightly dusted; third antennal segment orange; hairs on arista at least as long as diameter of arista. Hairs on sides of thorax with wavy tip; posterior margin of scutellum without bristles. Legs partly pale but femora largely black; hind tibia yellow or with indistinct dark smudge. Male: fore tarsus usually entirely pale. Female: posterior margin of tergite 3 with complete band of dense adpressed hairs; posterior third of tergite 4 with dense adpressed hairs; ground colour of abdomen shiny bronze. SIMILAR SPECIES For differences with Cheilosia species other than C. himantopus, see that species. Very similar to C. himantopus but flies in summer instead of spring, hardly or not overlapping; morphologically distinguished by having arista with longer hairs, hind tibia never with dark ring and male more frequently with fore tarsus entirely yellow (variable character though); female gives a more golden impression owing to denser and more golden hairs and by more bronzey sheen of body; hairs on posterior margin of tergites 3 and 4 denser and hairs on posterior part of tergite 4 more adpressed.

OCCURRENCE Widespread. C. canicularis and C. himantopus often share the same stand of Butterbur, but alternate throughout the year. Not known from Great Britain. ECOLOGY Habitats associated with rivers, roadsides or brooks that support Butterbur, but very mobile and often miles away from its larval habitat in drier habitats with large stands of hawkweeds. Visits yellow composites, particularly attracted to Canadian hawkweed. Larva mines the stem of Butterbur.

Early Butterbur Blacklet Cheilosia orthotricha IDENTIFICATION 12–15 mm. A very large Cheilosia. Eyes

with hairs, lower third to half bare; face bare and shiny; third antennal segment orange; arista almost bare, hairs at most half as long as diameter of arista. Hairs on posterior anepisternum straight, without wavy tip; posterior margin of scutellum without bristles. Femora largely black; tibiae yellow, at most with small, brown smudge on apical half but never with black ring; outer tarsomere distinctively black. SIMILAR SPECIES Very similar to C. canicularis and C. himantopus although flight season of C. canicularis very different, for differences with C. himantopus, see that species. Could be mistaken for C. albipila but larger, posterior anepisternum with straight hairs and females with largely black femora. Male like in C. flavipes but with frons largely covered with black hairs. Like C. chloris but lower third of eyes bare, hind tibia yellow (feature less helpful for females), fore tarsus of male with central tarsomeres pale and female has scutum with long erect yellow hairs. Like C. fraterna but much larger, scutum of male always without field of black hairs

between wings and central tarsomeres of fore tarsus pale, and female scutum with long erect yellow hairs. OCCURRENCE By far the rarest of the large Butterbur Cheilosia, local. Not known from Great Britain. ECOLOGY Small river valleys in forest, with Butterbur growing in the riverbed. A species with a very short flight period, largely preceding C. himantopus where the species co-occur. Adults are found on or near the host plant, males settle on the leaves and females fly among the plants. Unlike C. canicularis and C. himantopus, seemingly has no preference for yellow composites, but found on, for example, flowering Cow parsley and willow. Larva mines in Butterbur, in the lower half of the flowering stalks.

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Smudge-winged Blacklet Cheilosia nebulosa IDENTIFICATION 6–9 mm. A fairly small, broad-headed brownish

Cheilosia. Eyes with hairs; third antennal segment orange but usually slightly dark at tip and upper margin; arista dark orange; face bare; face wide, at level of antennae as wide as an eye; therefore, head appears large compared to rest of body. Posterior margin of scutellum without bristles. Wing: with faint dark smudges in centre and on outer half, although smudges can be indistinct and hardly discernible, crossvein r-m blackish. Legs extensively orange; hind tibia orange, sometimes with indistinct black ring; longest hairs on underside of hind femur equal width of hind femur. Male: frons dusted, swollen and largely covered with yellow hairs, with incomplete groove not reaching lunule but ending in a central pit, or only a central pit. SIMILAR SPECIES In the field, appears like a small C. albipila with remarkably wide head. Female differs from that species by having largely black femora, male by smudges on wing, wider face, frons dusted, more inflated and largely covered with yellow hairs, dark orange arista

and shorter hairs on underside of hind femur. Like C. uviformis, but posterior margin of scutellum without bristles; in male frons largely covered with yellow hairs and face wider; in female frons wider. Very similar to C. clama, and dark specimens of C. nebulosa may key out to that species when they have a black ring on tibia; for differences, see that species. OCCURRENCE A very rare species in areas where application of fertilisers and herbicides and land conversion have taken a heavy toll on permanent grasslands; elsewhere widespread but often very local and in low numbers. ECOLOGY Well-drained permanent grasslands, dykes, chalk and dune grasslands with Knapweed, near forest or scrubs. The adults have a preference for Blackthorn blossoms and willow catkins. Males hover 2–5 metres above the ground near bushes and along forest edge. Larval biology unknown, but egg-laying seen on Common knapweed.

Hidden Blacklet Cheilosia clama IDENTIFICATION 6–9 mm. A fairly small Cheilosia with a wide face. Eyes with pale hairs in male, bare in female; face wide, bare, shiny or with very thin dusting; third antennal segment completely bright orange; arista black, with very short hairs. Scutum and abdomen with pale hairs; upper and lower hair patches on katepisternum widely separated; posterior margin of scutellum without bristles, but sometimes with some black bristle-like hairs. Femora black except tip narrowly yellow; tibiae with wide black ring; at least upper side of all tarsomeres dark. Wing: transparent, crossvein r-m not dark, is same colour as other veins. Male: eyes meeting at an obtuse angle of 100–110°; frons strongly swollen, with black hairs, with longitudinal groove until lunule, with thin grey dusting, dusting thicker along eye margin; sternites with thin grey dusting. Female: scutum and abdomen with very short hairs; sternite 1 with thin grey dusting, remaining sternites shiny or very weakly dusted. SIMILAR SPECIES Much like C. nebulosa but legs more extensively black (however, dark-legged C. nebulosa exist and would key out to C. clama, so check additional characters), crossvein r-m not black, male with

distinct frontal groove reaching lunule, third antennal segment bright orange to tip and arista black. Male: wide face and large angle at which eyes meet distinguish it from all similar species; like C. chloris but smaller and arista black; like C. flavipes but tarsi black and frons with black hairs. Female: like other Cheilosia with bare eyes and partly pale legs, but combination of bare face, facial tubercle not widened and black tarsi distinguish it from all other species. OCCURRENCE Enigmatic species with dispersed records of singletons from Belgium to the Balkans. Not known from Great Britain. Visits flowers of willow and Marsh marigold. Larval biology unknown.

Cabbage Thistle Blacklet Cheilosia chloris IDENTIFICATION 8–11 mm. Medium-sized robust Cheilosia. Eyes

entirely covered with hairs; face bare; base of arista orange for at least twice arista width; arista almost bare. Posterior margin of scutellum without bristles, but in female sometimes with robust yellow hairs. Legs partly pale; hind tibia with a (sometimes faint) black ring. Male: frons largely covered with black hairs; hairs on eyes conspicuously long; scutum mostly with erect pale hairs. Female: scutum with pale adpressed hairs; hind femur below without black bristle-like hairs; abdomen in dorsal view convex, strongly widened halfway. SIMILAR SPECIES Much like C. fraterna but larger, arista pale at base, eyes entirely covered with hairs, hind tibia with black ring (although not always obvious) and male with exclusively pale hairs on scutum and female with wider frons. Like C. bergenstammi but posterior margin of scutellum without bristles, eyes entirely covered with hairs and arista with orange base. Differs from C. canicularis and C. himantopus by eyes being entirely covered with hairs, posterior anepisternum with straight hairs and hind tibia with black ring; moreover,

male differs by dark central tarsomeres of fore leg and female by adpressed hairs on scutum. Male differs from C. flavipes by black instead of yellow hairs on much of frons and by narrower orbital strip. OCCURRENCE A frequent species in the native North-west European range of its foodplant. Not known from Great Britain. ECOLOGY Wet grassland habitats on base-rich soil in and near forest, in the presence of Cabbage thistle. Flight period starts early, in March, but is long, lasting until June. Frequently visits Marsh marigold. Males hover about 1 metre above the ground at the forest edge. Larva mines Cabbage thistle.

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Orange-shinned Blacklet Cheilosia fraterna IDENTIFICATION 8–10 mm. A robust medium-sized Cheilosia.

Eyes with short, pale or dark hairs; lower half or quarter of eyes bare; face bare; third antennal segment largely orange. Posterior margin of scutellum with short yellow or black bristles, although sometimes absent; scutum with field of black hairs between wings, especially distinct in male, seldomly all hairs on scutum pale. Legs partly pale; hind tibia entirely yellow or at most with black smudge, but never with complete black ring. Sternites shiny. Male: if bristles on posterior margin of scutellum present, then bristles not longer than other hairs on scutellum; hind tibia below with row of black bristle-like hairs; fore tarsus usually black or very dark. Female: scutum covered with adpressed mostly golden hairs; wing often dark brownish; hind tibia below without row of black bristle-like hairs; abdomen in dorsal view convex, strongly widened halfway. SIMILAR SPECIES A common species that can be confused with wide array of other Cheilosia species, especially since bristles on posterior margin of scutellum can be present or absent. Hind tibia is either orange or has a black smudge, but never a black ring, excluding some quite similar species. Like C. bergenstammi, lower part of eyes bare, but C. fraterna flies in wetter habitats, has hind tibia without complete black ring, never has long bristles on posterior margin of scutellum, male has fore tarsus usually entirely dark (C. bergenstammi has basal three tarsomeres orange) and female lacks row of black bristle-like hairs on underside of hind femur and has wider abdomen. Especially females are much like C. chloris; for differences, see that species. Bare lower part of eyes shared only with C. bergenstammi, C. canicularis, C. himantopus and sometimes C. orthotricha; differs

from last three in being much smaller, amongst other differences. OCCURRENCE Widespread and fairly abundant in marshy habitats. ECOLOGY In wet open habitats such as marshes and wet grasslands. In Great Britain, the most frequent Cheilosia of upland grasslands where sheep and cattle grazing is not too heavy and thistles are frequent. Often found on buttercup. Larva mines in thistles, especially Marsh thistle.

Ragwort Blacklet Cheilosia bergenstammi IDENTIFICATION 8–10 mm. Medium-sized Cheilosia with yellow–

brown hairs. Eyes with hairs; however, lower half or quarter of eye bare; hairs on eye pale or dark; face bare; third antennal segment round and predominantly orange. Posterior margin of scutellum with bristles, in male almost always black, in female often with a few yellow ones. Legs partly pale; hind tibia with black ring; hind tibia below with row of black bristle-like hairs. Sternites shiny. Male: frons not swollen, thinly dusted; scutum with long erect grey–yellow to golden hairs. Female: facial tubercle and mouth edge protruding and tubercle set rather low when viewed from the side; scutum with very short semi-adpressed mostly golden hairs. SIMILAR SPECIES Unlike C. proxima and allies, sternites shiny and female tergites 2–4 without oblique patches of longer silver–grey hairs. Like C. fraterna, but hind tibia with black ring and posterior margin of scutellum always with bristles, which in male are longer than other hairs on scutellum; also, fore tarsus of male usually with basal tarsomeres bright orange and female with less wide abdomen and hind tibia below with row of black bristle-like hairs. Unlike male C. mutabilis, third antennal segment orange, legs paler, individuals distinctly larger and less elongated. Like C. carbonaria and C. cynocephala, but more shiny bronze instead of black or blue–black, legs paler with less than half of hind tibia black and hind tarsus with middle tarsomeres dark but not black, eyes bare on lower part and elsewhere eyes with paler hairs. Not unlike C. urbana and C. psilophthalma but much larger and less elongated, third antennal segment rounder, lower part of eyes bare, hind tibia below with row of black bristle-like hairs and scutum in females with shorter, adpressed instead of erect hairs. Like C. lenis, but that species has eyes entirely covered with very long and in male black hairs, and male has frons slightly

swollen and shiny. Unlike C. vernalis, hairs on eyes pale and absent on lower half. Like C. uviformis but sternites shiny, male with frons shinier and in female hind tibia below with row of black bristle-like hairs, eyes with denser hairs and facial tubercle and mouth edge more protruding. Smaller than C. canicularis and C. himantopus and posterior margin of scutellum with bristles. OCCURRENCE A widespread species especially in grazed pasture, where the foodplant thrives. ECOLOGY Mainly found on dry pasture, brownfield lands and other open habitats with Ragwort. Visits the flowers of yellow composites, including the foodplant but also dandelions and similar composites. Larva mines the stem and roots of ragworts, mainly Common ragwort.

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c laws

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Pale-clawed Blacklet Cheilosia urbana IDENTIFICATION 6–8 mm. A small slender brownish Cheilosia.

Eyes with hairs; hairs on eyes pale; face bare; arista almost bare, hairs much shorter than diameter of arista; third antennal segment 1.5 times as long as wide, variable in colour, ranging from orange–red to blackish, but usually dark brownish. Scutum with pale and erect hairs; posterior margin of scutellum with bristles. Femora black except tip; tibiae in male orange with black ring, in female usually entirely orange or with indistinct black smudge only; hind tarsus with central tarsomeres pale; tarsomere 1 of hind tarsus in side view slightly thicker than tip of hind tibia; underside of hind femur without (females) or with sparse black bristle-like hairs restricted to tip; claws (sometimes dark) orange on basal half, apical half black, best assessed with a microscope. Sternites shiny. Male: frons not swollen; eyes meeting over a distance of 1.5 times the length of frons; eyes meeting at a right angle; genitalia: gonostylus with long dorsal projection not strongly curved inwards. SIMILAR SPECIES For differences with Cheilosia other than C. psilophthalma, see that species. Very similar to C. psilophthalma; colour of claws is a reliable character, basal half orange in C. urbana, claws entirely black or base at least blackish in C. psilophthalma; in male, gonostylus longer and not strongly curved inwards; other supportive, not always reliable, characters include: swollen tarsomere 1 of hind leg, male with less swollen frons, eyes meeting over a longer distance and at a right angle and female with narrower frons and tip of hind femur more extensively orange. OCCURRENCE A very widespread species in Europe, occurring from sea level to high mountains; can be locally abundant. ECOLOGY A variety of short grasslands,

mainly on well-drained soil, along forest edge, forest tracks, parks, along hedges. Males hover in groups in sheltered spots and near flowering bushes 2–5 metres above the ground. Visits flowering bushes such as willow and Blackthorn. Larva mines in roots of Mouse-ear hawkweed, but egg-laying has been observed on other hawkweeds as well.

Dark-clawed Blacklet Cheilosia psilophthalma IDENTIFICATION 6–8 mm. A close relative of C. urbana. Eyes

with pale hairs; face bare; third antennal segment 1.5 times longer than wide, variable in colour, ranging from orange–red to blackish, but usually quite orangish; arista almost bare, hairs much shorter than diameter of arista. Scutum with pale and erect hairs; posterior margin of scutellum with bristles. Femora largely black, except tip; tibiae in male yellow with black ring, in female usually entirely orange or with indistinct black smudge; underside of hind femur without (females) or with sparse black bristle-like hairs restricted to tip; hind tarsus with central tarsomeres pale; tarsomere 1 of hind tarsus in side view not thickened, thus as wide as tip of hind tibia; claws entirely dark, basal half barely paler than apical half, best assessed with a microscope. Sternites shiny. Male: frons slightly swollen; eyes meeting over a distance similar to length of frons between eyes and lunule; eyes meeting at angle of 90–100°; genitalia: gonostylus with short strongly inward-curved dorsal projection. SIMILAR SPECIES Very similar to C. urbana; for differences, see that species. Shares small and slender appearance with C. mutabilis, but that species has hind tarsus black, arista with longer hairs, male with black hairs on scutum and female with no hairs on eyes or hairs shorter and sparser. Like C. uviformis but that species has sternites lightly dusted, is larger, has round and brighter orange third antennal segment, male has frons with thicker dusting and female has eyes nearly bare. Differs from C. bergenstammi by combination of being smaller and slenderer, black bristle-like hairs on underside of hind femur being sparse or absent and third antennal segment 1.5 times longer than wide instead of round. OCCURRENCE Widespread, found over most of the range of the common C. urbana, but nearly always much rarer. ECOLOGY A variety of short grasslands, mainly on well-drained soil,

along forest edge, forest tracks, parks, along hedges. Often occurs in smaller numbers with C. urbana. Males hover along forest edge 1–3 metres above the ground. Visits yellow composites and flowering bushes such as willow and Blackthorn. Larva mines the stem and leaves of Mouse-ear hawkweed, but possibly also other hawkweeds.

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Yarrow Blacklet Cheilosia vernalis IDENTIFICATION 5–8 mm. A variable small compact Cheilosia.

Eyes with dark hairs; face bare; facial tubercle and mouth edge moderately protruding; colour of third antennal segment variable, ranging from red to black. Hairs on scutum variable, from yellow to mostly black; posterior margin of scutellum with bristles; scutum and abdomen shiny black. Wing: transparent. Legs partly pale; tibiae pale at both ends; amount of orange on legs very variable, but pale parts always bright orange; hind tibia below with black bristle-like hairs. Abdomen short and rounded, widest at posterior corner of tergite 2, whereafter decreasing again; sternites shiny. SIMILAR SPECIES Appears darker and blacker than, for example, C. bergenstammi and C. urbana. Smaller than C. bergenstammi and C. fraterna and eyes with hairs all over and hairs longer and darker. Having dark hairs on eyes distinguishes it from all similar species except C. carbonaria and C. cynocephala; like C. carbonaria but smaller, clearer wings, face less protruding downwards, hind tibia with pale tip, sides of abdomen in male

not parallel, in female abdomen widest at posterior corner of tergite 2 and frons wider. Can be very similar to C. cynocephala; for differences, see that species. OCCURRENCE Widespread and frequent, found in many different habitats and has several generations a year. ECOLOGY Various habitats such as forest clearings, forest edge, road verges, brownfield lands and open pastures. Males hover up to 3 metres above the ground in sheltered places. Visits low flowers including white umbellifers and yellow composites. Larva mines different plants, including Smooth sow-thistle, Yarrow and Scentless mayweed. COMMENT Owing to the large morphological variation in this species, several species were initially described, including C. rotundiventris and C. ruficollis, but these are currently seen as variations in C. vernalis.

Blue Blacklet Cheilosia cynocephala IDENTIFICATION 7–9 mm. A medium-sized dark blue–black

Cheilosia. Eyes with dark hairs; face bare; orbital strip fairly wide; face moderately protruding. Posterior margin of scutellum with bristles; scutum in living specimens with blue sheen. Wing: tip dark, in female more distinct than in male. Legs partly pale, pale parts often dirty orange. Abdomen slightly elongated, widest at posterior corner of tergite 3; sternites shiny. Male: scutum mostly covered with black hairs, hairs of different lengths; abdomen with dense erect somewhat bristle-like strong black hairs. Female: frons coarsely punctate between eyes and longitudinal grooves, side margin of tergite 4 with black hairs. SIMILAR SPECIES Like C. carbonaria; for differences, see that species. Much like darkest examples of C. vernalis with black hairs, especially in collected specimens difference is subtle and these species are often confused. C. cynocephala on average larger, has abdomen longer, legs on average darker, with blue sheen on scutum (only in living specimens), with dark patch in wing-tip, male with hairs on abdomen more bristle-like. OCCURRENCE Widespread but localised. Its foodplants may increase exponentially in response

to disturbance (floods, human interventions) causing a surge in C. cynocephala; however, both plants and the fly may quickly disappear again. ECOLOGY River floodplains, riparian vegetation, chalk grasslands, arable margins, flood banks and brownfield lands on base-rich soils, as long as large stands of its foodplants Musk thistle or Welted thistle are present. Flies low through the vegetation. Larva mines the stem of Musk thistle and to a lesser extent Welted thistle.

Sooty Blacklet Cheilosia carbonaria IDENTIFICATION 9–10 mm. Medium-sized black slender Cheilosia with long wings. Eyes with dark hairs; face bare; facial tubercle and mouth edge well developed and protruding downwards; frons narrow, so head small; third antennal segment round and orange–red, sometimes dark but not black. Posterior margin of scutellum with bristles; scutum and abdomen shiny black. Wing: apical half dark, wing relatively long. Legs dark, sometimes almost black, sometimes tibiae pale at base or at base and tip; underside of hind femur with short black bristles. Sternites shiny. Female: abdomen with typical shape, widest point at posterior corner of tergite 3. SIMILAR SPECIES Like C. bergenstammi and C. urbana, but hairs on eyes darker and legs darker. For differences with C. vernalis, see that species. Like C. cynocephala, but slenderer, legs darker, larger, face more protruding downwards, less dark wing-tip, wing longer and slimmer, never with blue sheen on scutum and female with more trapezoidal abdomen, and frons narrower and more finely punctate. OCCURRENCE Very scarce and sporadic in Great Britain.

In years when it is more abundant, can be seen well away from the usual habitats. ECOLOGY Forest glades and in grasslands around forests on wet, base-rich soil, floodplains, locally common in moist unimproved grasslands with base-rich seepages. In Great Britain, usually found in older woodlands not necessarily on baserich soils. Larval biology unknown.

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Silver-fronted Blacklet Cheilosia uviformis IDENTIFICATION 7–9 mm. Small to medium-sized, fairly elongated

Cheilosia resembling a largish C. pagana. Eyes with hairs in male, eyes with only sparse hairs or bare in female; hairs on eyes pale; face bare; third antennal segment about a long as wide, bright orange with narrowly dark upper outer corner; arista almost bare. Scutum with erect white–yellow hairs; posterior margin of scutellum with bristles. Hind tibia yellow, usually with indistinct black ring or smudge; basal tarsomeres of fore and mid tarsi pale, tarsomere 5 black; underside of hind femur without black bristle-like hairs. Sternites with thin dusting. Male: frons dusted, with distinct longitudinal groove. Female: third antennal segment rather large, frons dusted anteriorly; abdomen bronze without oblique patches of longer silver–grey hairs. SIMILAR SPECIES Not exactly the easiest Cheilosia to identify owing to few distinctive, but many variable, characters. Sternites are only thinly dusted, making confusion possible with species with and without dusted sternites. If female has eyes bare, could be mistaken for C. pagana, but can be distinguished by sternites thinly dusted, third antennal segment smaller and always with dark upper outer corner (entirely orange and very large in C. pagana). Similar to C. bergenstammi and C. urbana, but sternites thinly dusted and male frons is thickly dusted; in female, dusting on sternites can be almost absent, so useful distinguishing features are: hind femur without black bristle-like hairs, third antennal segment rounded and orange and with dark tip and eyes with sparse hairs. Like C. proxima and allies, but sternites only thinly dusted and third antennal segment orange, male with dusted frons and female without oblique patches of longer silver–grey hairs on abdomen. Like C. rufimana,

but usually smaller, sternites less heavily dusted, upper and lower hair patches on katepisternum distinctly separated and hind femur usually without black ring. OCCURRENCE Widespread but localised and in low numbers. A rather inconspicuous and rare species that is easily overlooked. ECOLOGY Forest glades along rivers or seepages, willow or alder carr, wet tall-herb grasslands near forest. Males hover 2–10 metres above the ground, for example at forest edges. Mainly visits flowers of willow and Blackthorn, also white umbellifers. Larval biology unknown, but Meadowsweet or especially Valerian are suspected foodplants.

Mullein Blacklet Cheilosia aerea IDENTIFICATION 7–9 mm. Medium-sized compact brown–black

Cheilosia. Eyes with hairs; face bare; third antennal segment ranging from brown–black to orange, in male on average darker than in female; facial tubercle and mouth edge moderately developed. Scutum coarsely punctate: space between dots 2–3 times dot diameter; anterior anepisternum with hairs in upper posterior corner; posterior margin of scutellum with bristles. Legs partly pale. Sternites dusted. Male: scutum with long pale hairs and a field of very short black hairs just before scutellum. Female: hairs on scutum pale, semi-erect; tergites 2–4 with oblique patches of longer silver–grey hairs. SIMILAR SPECIES Much like C. proxima and C. velutina; differs from these and all other similar Cheilosia by anterior anepisternum with hairs in upper posterior corner, bare in other species; unfortunately, this character is hard to judge in the field or from photos, so collecting is usually necessary to confirm identification. Other differences with similar C. proxima are scutum coarsely punctate and in male the field of short black hairs on scutum between wing bases. Compared to C. velutina, facial tubercle and mouth edge better developed. C. aerea is, unlike C. rufimana and C. uviformis, a black shiny species. OCCURRENCE A common and widespread species in southern Europe, reaches its northern range limit in Belgium and the south of the Netherlands and is confined there to the warmest habitats. Not known from Great Britain. ECOLOGY On warm, well-drained, south-exposed chalk grassland, old quarries, along south-faced forest edges on chalk. Frequently visits white umbellifers, including Wild carrot. Larva has been found in several species of mullein.

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♂

head

♀ ♂

head

s t er nit es

♂

hind f emur

a nte ro do rsa l ha i r f ri nge l o nge r tha n a nte ro v e ntra l ha i r f ri nge

stern i tes dusted

stra i ght wi th b ri stl es ho o k

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s c ut ellum

♂

gonosty lus

♂ g e n i ta l i a ve n tra l vi e w

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head

♀

head

♂

♂

hind femur

a ntero do rsa l ha i r fri n ge n o t l o nger th a n a n tero ventra l ha i r fri n ge do rsa l l o be si m pl e

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gonosty lus

co nca v e

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Dull-bellied Blacklet Cheilosia proxima IDENTIFICATION 7–9 mm. A medium-sized compact Cheilosia.

Eyes with pale hairs; face bare; face with broad, distinct facial tubercle and mouth edge, distinctly concave between; lunule dark orange to black; third antennal segment brown–black, but sometimes dark orange below, especially in female. Posterior margin of scutellum with bristles, bristles longer than scutellum; anterior anepisternum bare; scutum finely punctate: space between dots c. 5 times dot diameter. Fore and mid tibiae pale at both ends. Sternites dusted. Fairly well-developed seasonal dimorphism, with spring individuals on average larger, hairier with more extensive yellow hairs. Male: frons shiny; hind femur with anterodorsal hair fringe longer than anteroventral hair fringe; abdomen partly covered with black hairs, at least pregenital segments with few black hairs; centre of tergites 2 and 3 usually without field of black hairs just before posterior margin; genitalia: dorsal lobe of gonostylus with a more or less distinct hook on its dorsal margin; inner side of surstylus in ventral view straight. Female: dust spots on frons very small or absent; hind femur without anteroventral hair fringe, occasionally with single longer hairs which are shorter than, or rarely as long as, diameter of hind femur; tip of hind femur below usually without black bristles; tergites 2–4 with oblique patches of longer silver–grey hairs. SIMILAR SPECIES Very similar to C. gigantea; for differences, see that species. Dusted sternites distinguish it from C. bergenstammi and allies. Seldomly female with third antennal segment distinctly orange below, if so, can be confused with C. uviformis, C. rufimana and (sometimes) C. velutina; facial tubercle better developed compared to C. velutina, for more

differences, see that species. Unlike C. uviformis and C. rufimana, a black shiny, less shiny-bronze species and in male, abdomen partly covered with black hairs and frons shiny. Much like C. aerea but anterior anepisternum bare; for more differences, see that species. OCCURRENCE A widespread and frequent Cheilosia in North-west Europe. ECOLOGY In and near forest and scrub but also in unimproved grassland and rough grasslands, possibly with a preference for base-poor soil. Males hover up to several metres above the ground or sit on leaves in sunny spots at the forest edge. Often visits umbellifers including hogweed and Wild carrot. Larva mines thistles such as Marsh thistle and Cabbage thistle.

Greater Dull-bellied Blacklet Cheilosia gigantea IDENTIFICATION 7–12 mm. Like a large version of the common

C. proxima. Eyes with pale hairs; face bare; face with distinct facial tubercle and mouth edge, distinctly concave between; lunule dark orange to black; third antennal segment brown–black, sometimes dark orange below, especially in female. Posterior margin of scutellum with bristles, bristles longer than scutellum; anterior anepisternum bare. Fore and mid tibiae pale at both ends, although pale parts quite dark orange in male. Sternites dusted. Male: frons shiny; hind femur with anteroventral hair fringe as long as or longer than anterodorsal hair fringe; abdomen partly covered with black hairs, at least pregenital segments with few black hairs; genitalia: dorsal lobe of gonostylus simple; inner side of surstylus in ventral view concave. Female: dust spots on frons very small or absent; hind femur on anteroventral side with long hair fringe, hairs often obviously longer than diameter of hind femur; tergites 2–4 with oblique patches of longer silver–grey hairs. SIMILAR SPECIES For differences with species other than C. proxima, see that species. Very similar to C. proxima; usually distinctly larger but occasionally can be small; C. proxima, however, never large, so large specimens are always C. gigantea and small specimens are usually but not always C. proxima. Most reliable field character is long hair fringe on anteroventral side of hind femur: as long as or longer than anterodorsal hair fringe in male, obviously longer than diameter of hind femur in female, in C. proxima hair fringe is much shorter in male and absent or with only a few long hairs in female. Male differs in genitalia: surstylus seen from front has concave instead of straight inner side and dorsal lobe of gonostylus simple instead of with a more-or-less distinct hook on its dorsal margin. Female always has tip of hind femur below with black bristles, which are usually but not always

absent in female C. proxima. OCCURRENCE A northern species occurring at sea level south to Denmark and northern Germany, but restricted to mountain ranges in Central Europe and further south. Not known from Great Britain. ECOLOGY Open ground, unimproved damp grassland, often near forest and water. Larva known from several large dock species including Western dock.

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head

♂ f ro ns duste d l unul e ye l l o w

wide black ri ng

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head

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wi de b l a ck ri ng

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head

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head

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f a ci a l tube rcl e i ndi sti nct

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head

s t er nit es

f a ci a l tube rcl e i ndi sti nct sterni tes dusted l o ng a nd pa l e ha i rs

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Knotweed Blacklet Cheilosia rufimana IDENTIFICATION 7–12 mm. Quite large, shiny bronze species. Eyes with pale hairs; face bare; facial tubercle broad, well developed; third antennal segment largely bright orange; lunule orange or yellow (often darkens in dead specimens). Anterior anepisternum bare; posterior margin of scutellum with bristles, sometimes yellow. Wing: yellow–brown and dark along anterior margin. Legs partly pale; hind femur with wide black ring. Sternites densely dusted. Male: frons thinly dusted; scutum and abdomen with golden-yellow hairs. Female: abdomen with oblique goldenyellow hair patches on tergites 2–4. SIMILAR SPECIES Brownish appearance similar to that of C. bergenstammi and allies, but sternites densely dusted. Much like C. proxima and C. gigantea but with bronze sheen, third antennal segment at least below bright orange, lunule paler and in male frons lightly dusted. Lunule distinctly pale, yellowish or orange, but this occurs to some extent in other species as well. Like C. uviformis, owing to orange third antennal segment, dusted sternites and bronzy sheen, but dusting on sternites denser, upper and lower hair patches on katepisternum connected and always with wide black ring on hind tibia. OCCURRENCE A rather rare, localised mainly Central European spring species, but widespread in Denmark and the east of Belgium. Not known from Great Britain. ECOLOGY Wet tall-herb grasslands in and near forest and often near rivers. Visits mainly flowers of Cow parsley and other umbellifers. Males hover in groups in the forest edge or woodland rides 2–5 metres above the ground. Larval biology unknown but probably lives in knotweeds.

Chinless Blacklet Cheilosia velutina IDENTIFICATION 7–9 mm. Medium-sized compact brown–black

Cheilosia. Eyes with pale hairs; face bare; facial tubercle and mouth edge indistinct, face between facial tubercle and mouth edge almost vertical or retreating; third antennal segment orange–red to brown, usually dark in upper part and apical half. Scutum coarsely punctate; anterior anepisternum bare; posterior margin of scutellum with bristles. Hind tibia with black ring. Sternites dusted. Male: scutum with pale hairs of equal length; centre of tergites 2 and 3 with field of black hairs just before posterior margin. Female: triangular dust spots on frons along eyes quite distinct and large, sometimes connected; tergites 2–4 with oblique patches of longer silver–grey hairs; fine dusting on tergite 3 narrowly interrupted in middle, leaving a narrow dark longitudinal stripe (best viewed from an oblique angle). SIMILAR SPECIES Useful feature is the poorly developed facial tubercle and vertical-to-retreating mouth edge, distinguishing it from all similar species. Compared to C. proxima, scutum more coarsely punctate, third antennal segment more often orange; male has hairs on scutum of uniform length and abdomen with field of black hairs on tergites 2 and 3 just before posterior margin; female with shiny longitudinal stripe on centre of tergite 3 and larger dust spots on frons. Posterior margin of posterior anepisternum without black bristle, usually present at C. proxima and allies. Like C. aerea; for differences, see that species. OCCURRENCE Widespread but its presence is erratic and unpredictable. Generally scarce and infrequent. ECOLOGY Habitat affinity is still poorly understood, can be abundant at well-drained brownfield lands, railway embankments, but also on chalk grassland and forest clearings, often in habitats with Wild carrot. Males hover up to several metres above the ground near trees

and bushes. Visits flowers, including Wild carrot, hogweed and other umbellifers. Larva undescribed, but possibly mines Marsh thistle and figworts.

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a b d o me n

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b l a ck b ri stl e s

a ri sta bl a ck k nob ha l tere d a rk crossvei ns da rke ne d

a n te n n a

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a b d o me n

bl a ck b ri stl es

a ri sta o ra nge

k nob halte re ora n ge

co l d b ra ssy-shi ni ng a n te n n a

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head

ante nnae l o nger than he a d

♂

a nte nna e l o nge r tha n he a d

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a b d o me n

unm i sta k a bl e !

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Eurasian Copperback Ferdinandea cuprea IDENTIFICATION 7–12 mm. An attractive, shiny-brassy hoverfly. Face yellow; frons protruding conically forwards at level of antenna attachment; arista black. Scutellum orange–brown; scutum with grey-dusted longitudinal stripes; sides of scutum besides normal hairs also with long black bristles. Wing: with dark crossveins; haltere knob dark red to black, darker than stalk of haltere. Legs entirely yellow except outer tarsomeres; fore and mid leg with some scattered black bristles. Abdomen with golden-yellow hairs and strong brassy sheen; posterior margin of tergites dull, but even under perfect conditions this character can be very hard to assess. Female scutum with olive-green ground colour. SIMILAR SPECIES Owing to appearance (black bristles on scutum rarely found in hoverflies, but common in other flies) and behaviour, sometimes not immediately recognised as a hoverfly, but venation of wing distinctive. Much like F. ruficornis; for differences, see that species. Vaguely resembles Caliprobola speciosa but that species much larger and more elongated,

lacks black bristles on scutum and has crossveins in wing not dark. OCCURRENCE A widespread species, found in a variety of habitats where mature trees are present. ECOLOGY Most common in broad-leaved forests and parks, but also in open land with scattered trees and hedge trees. Often seen in numbers on scabiouses, thistles, ivy, Greater celandine, Common chicory or yellow composites such as Wall lettuce, usually in the morning or in partial shade. Often sits on trunks in the sun or on the ground along tracks and sunny forest glades. Larva lives in sap wounds, decaying tree trunks but also recorded from the roots of artichoke.

Orange-horned Copperback Ferdinandea ruficornis IDENTIFICATION 8–12 mm. A smaller less brassy version of

F. cuprea. Face yellow; frons protruding conically forwards at level of antenna attachment; arista orange, but males very often have arista almost completely dark brown to blackish, especially early in year. Scutellum orange–brown; scutum with grey-dusted longitudinal stripes; sides of scutum besides normal hairs also with long black bristles. Wing: with dark crossveins; both stalk and knob of haltere orange, but knob darkens somewhat in dead specimens. Legs without or with very few black bristles. Abdomen cold shiny-brassy colour with golden-yellow hairs in female, and blue–black to cold shiny-brassy colour with white–yellow hairs in male; dull bands on tergites separated from posterior margin by a narrow shiny strip, but this subtle character is often difficult to assess. Female scutum largely with blue–black ground colour. SIMILAR SPECIES For differences with species other than F. cuprea, see that species. Much like F. cuprea but arista orange – a feature always useful in identifying female, but male can have almost completely dark arista. Therefore, check for paler haltere knob, and fore and mid legs without or almost without black bristles; general

body colouration different: male has body hairs often shorter, paler, more whitish and has a more silver–blue rather than brassy sheen. OCCURRENCE Widespread but scarce, probably underrecorded as it does not often visit flowers. A strong hill-topper; can be abundant on hills. ECOLOGY Broad-leaved forests, often in oak forest. Probably highly arboreal, seldomly observed on flowers, most often near sap runs. Sits on sunlit trunks. Larva lives in cavities and sap runs of trees.

Vermillion Fly Psarus abdominalis IDENTIFICATION 8–9 mm. Enigmatic hoverfly with red abdomen and long antennae. Face black; frons at level of antennae conically protruding forward; antennae long, arista white; in side view, antennae longer than head. Scutum and scutellum black. Abdomen largely red but base and tip black, red marking sometimes with incision in anterior and posterior margin. Femora black, tibiae and tarsi brown. Wing: dark and with dark spots in middle and on crossvein r-m. Male: eyes nearly meeting. SIMILAR SPECIES None. Combination of predominantly red abdomen and long antennae distinguishes it from all other hoverflies. Wing: venation differs from similar-looking flies in other families. OCCURRENCE This single representative of a European endemic genus has strongly declined and has disappeared from North-west Europe, with the abandonment of coppice management. Not known from Great Britain. ECOLOGY Oak forests, mainly forest with coppice or coppice with standards management to maintain open freshly-cut plots at regular times. Forages at ground level early in the day on, for example, Bloody

crane’s-bill along forest edges and tracks. Males sit on twigs and leaves of oaks in the forest edge and keep returning to these spots. Larval biology unknown.

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a b d o me n o f te n w i th bl a ck m e di a n stri pe

sno ut v e ry l o ng

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head

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head

ant enna b l a ck ri ng

sh o rt h a i rs

♂

hind ti b i a

♀

a b d o me n

♂

♂

head

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head

ant enna enti re l y o ra n ge pa l e sh o rt h a i rs or ba re

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hind tarsus

♂

h i n d ti b i a

♀

a b d o me n

♂

sno ut re l a ti v e l y sho rt

♂

ant enna b l a ck

l ong h a i rs

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hind tarsus

♂

head

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head

h i n d ti b i a

exte nsi v e l y bl a ck

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Common Snout Fly Rhingia campestris IDENTIFICATION 8–11 mm. One of three hoverfly species with a short orange–red abdomen and very long snout. Face very long, greatly elongated; arista with hairs shorter than width of arista at base. Femora extensively black at base; hind tibia with dark ring in middle. Tergites 2–4 with black side margins and usually black central longitudinal stripe on tergite 2–3, usually also with black posterior margin. Male: scutellum with orange hue (rarely, almost black and of same colour as scutum); scutum with grey-dusted longitudinal stripes on green–black background. SIMILAR SPECIES The combination of long snout and convex red abdomen also in some Brachyopa species, but their snout never this long nor pointed. Male: differs from R. rostrata by tergites having black edges and dark medial stripe, longer snout and black ring on hind tibia; differs from R. borealis by longer snout, shorter hairs on arista and dark orange scutellum. Female: can be identified from R. borealis and R. rostrata by black base of femora instead of almost or entirely orange in the other two.

OCCURRENCE One of the commonest hoverflies in pasture, but can be rare in pristine or dry environments. ECOLOGY Pasturerich landscapes, but will wander into surrounding habitats such as woodland, parks and gardens, also marshes and herb-rich grasslands. Flies among low vegetation and frequently settles on leaves. Often visits flowers with deep nectaries in the sage family, for example, Ground ivy and Bugle, also brambles, raspberry, scabiouses, bluebell. Males hover in groups at hill-tops. Larva semi-aquatic, living in cow pats and possibly other dung, likely also in silage or other forms of wet decaying organic matter.

Orange Snout Fly Rhingia rostrata IDENTIFICATION 8–10 mm. An extensively orange Rhingia. Arista

almost bare, in female sometimes with very short hairs. Male: scutellum orange, contrasting with darker scutum; scutum with grey-dusted longitudinal stripes on blue–black background; hind tibia entirely orange; tergites 2–4 entirely orange, at most posterior margin narrowly black, dark central longitudinal stripe absent or restricted to tergite 2. Female: legs almost entirely orange; femora entirely orange, sometimes narrowly black at very base; upper side hind tarsus partly dark, underside paler. SIMILAR SPECIES Male: unlike R. borealis, with pale scutellum and dusted scutum; like R. campestris but hind tibia orange and abdomen without dark edges and medial stripe not beyond tergite 2. Female: like R. campestris, but femora largely or entirely orange; like R. borealis but arista bare and hind tarsus on at least underside extensively orange. OCCURRENCE Arguably the most spectacular come-back of a hoverfly in recent history in Europe, after a continental-wide dramatic decline, now again widespread and locally fairly common and much expanded in Britain but still less common than R. campestris. The reason is largely unknown.

ECOLOGY More strongly associated with woodland than

R. campestris but will be present in other habitats nearby. Visits flowers at forest edges, in forest glades and settles on leaves. Often visits flowers with deep nectaries, for example Ground ivy, also brambles, scabiouses and thistles. Larval biology insufficiently known, but possibly associated with dung of large wild mammals.

Forest Snout Fly Rhingia borealis IDENTIFICATION 6–8 mm. A small dark-orange to yellow–orange

Rhingia. Arista with hairs longer than width of arista at base; snout relatively short. Male: snout short and curved; scutellum black; scutum shiny black without grey longitudinal stripes; femora largely black, only tip sometimes paler; tergites almost entirely orange or yellowish but darker individuals sometimes extensively black along edges. Female: femora predominantly orange; tip of hind tibia dark; hind tarsus completely dark, blackish. SIMILAR SPECIES Male: compared to R. campestris and R. rostrata, smaller, snout shorter, scutellum black instead of reddish, scutum shinier, hind femur blacker and arista with longer hairs. Female: differs from R. campestris by largely or entirely orange femora and arista with hairs; much like R. rostrata but arista with hairs, other indicative character is black hind tarsus, versus at least underside extensively orange in R. rostrata, seen by looking through black bristles. OCCURRENCE A local species in low mountain ranges in Central Europe, easily overlooked because it flies in full shade, whereas other hoverflies are found in open sunny spots.

Not known from Great Britain. ECOLOGY Marshy ground near seepages or brooks in the forest interior. Visits low flowers such as those of Water avens and bugles in shade and partial shade in the forest. Larval biology unknown.

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a b d o me n

ta rs i pa rtl y da rk

♂

th o ra x l a te ra l

a n teri o r a ne pi ste rnum ha i re d

♀

fo re a nd mi d ta rsi yel l ow

a b d o me n

♂ l a rge unduste d spo ts

th o ra x l a te ra l

♂

head a nte ri o r a ne pi ste rnum ba re

a nteri o r pa rt l unul e d usted l o ng pa l e ha i r fa ce dusted

♀

a b d o me n

tars i partl y d a rk sm a l l duste d spo ts

♂

♂

th o ra x l a te ra l

head

l u nul e sh i ny

a nteri o r a ne pi ste rnum ba re

b l a ck med i a n stri p e

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Dune Bighorn Fly Pelecocera lugubris IDENTIFICATION 5–8 mm. A slender small unobtrusive greyish fly. Lower half of face protruding forwards; third antennal segment very large; arista attached just after middle of third antennal segment; posterior margin of lunule shiny but triangular part between antennae dusted. Anterior anepisternum with white hairs (not to be confused with dense microscopic hairs); posterior margin of posterior anepisternum without long pale hair. Wing: entirely covered with microtrichia. Fore and mid tarsi with tarsomeres 3 and 4 brown, darker than tibiae. Abdomen with three or four pairs of small yellow or orange spots with variable grey dusting. Male: eyes widely separated; face dusted except black medial stripe. SIMILAR SPECIES Like P. tricincta, but arista not attached on top outer corner of third antennal segment. Like P. scaevoides and P. caledonica, but anterior anepisternum with white hairs, instead of bare; differs from P. caledonica by partly dusted lunule and wing entirely covered with microtrichia, and from P. scaevoides by darker tarsi and male by black medial

stripe on face. Differs from Platycheirus and Melanostoma species by shape of face and large third antennal segment. OCCURRENCE Widely scattered populations over the range covered by this book, but very localised, can be abundant in suitable habitat. ECOLOGY Sand dunes and heathland partly covered by pine wood, often near the transition from woodland or scrub to open sand. Mainly visits flowering Common heather. Females have been observed egg-laying in the sand near pine trees, possibly the larva lives in false truffles. COMMENT Until recently, mainly known under the name P. lusitanica.

Orange-spotted Bighorn Fly Pelecocera scaevoides IDENTIFICATION 4–8 mm. A Pelecocera with large orange spots on abdomen. Lower half of face protruding forwards; posterior margin of lunule shiny but triangular part between antennae dusted; third antennal segment very large; arista attached just after middle of third antennal segment. Anterior anepisternum bare; posterior margin of posterior anepisternum with a long pale hair. Wing: entirely covered with microtrichia. Tarsomeres 3 and 4 of fore and mid tarsi pale, same colour as tibiae. Spots on abdomen without grey dusting, spots on over half the length of tergites, and sometimes connected. Male: eyes widely separated; face entirely dusted. SIMILAR SPECIES Similar to P. tricincta owing to large orange abdominal spots that are sometimes fused to bands; however, arista not attached on top outer corner of third antennal segment. Like P. lugubris and P. caledonica, but tarsi paler and male with face entirely dusted; differs from P. lugubris by bare anterior anepisternum and from P. caledonica by larger abdominal spots that are less dusted, wing entirely covered with microtrichia and lunule partly dusted. Differs from Platycheirus and Melanostoma species by shape of face and large third

antennal segment. OCCURRENCE Very rare in the range covered by this book, restricted to upland areas: a large population in the Scottish Highlands and some isolated, often non-persistent small populations in low mountain areas on the continent. ECOLOGY Pine woodland and pine plantations. Larval biology unknown, but possibly associated with false truffles or other (underground) fungi linked to pines.

Silver-spotted Bighorn Fly Pelecocera caledonica IDENTIFICATION 4–7 mm. Unobtrusive small hoverfly with pairs of small grey-dusted spots on abdomen. Lower half of face protruding forwards; third antennal segment very large; arista attached just after middle of third antennal segment; lunule entirely shiny. Anterior anepisternum bare; posterior margin of posterior anepisternum without long pale hair. Wing: cell bm and cell br largely bare, without microtrichia. Fore and mid tarsi with tarsomeres 3 and 4 brown, darker than tibiae. Abdomen of male with three, female with four, pairs of small grey-dusted spots that occupy less than half the length of tergites. Male: eyes widely separated; face dusted except black medial stripe. SIMILAR SPECIES Could be mistaken for P. tricincta, but arista not attached on top outer corner of third antennal segment. Differs from P. lugubris and P. scaevoides by having lunule entirely shiny and base of wing extensively bare, without microtrichia; also, tarsi darker and abdominal spots smaller and more dusted compared to in P. scaevoides, and anterior anepisternum bare, while with hairs in P. lugubris. Differs from Platycheirus and Melanostoma

species by shape of face and large third antennal segment. OCCURRENCE Much rarer than other Pelecocera; in the range covered by this book, only very localised in Scotland, a recent record in Belgium and some old observations in the Netherlands (now extinct). ECOLOGY In or near pine forest and plantations. Larval biology unknown, but possibly associated with false truffles or other (underground) fungi linked to pines. COMMENT P. lugubris, P. scaevoides and P. caledonica were, until recently, mainly known under the genus name Chamaesyrphus, but genetic evidence suggests they are all Pelecocera.

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a b d o me n

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a ri sta o n outer to p corne r

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3 r d a nten na l seg m e nt v e ry l a rge

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head

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♀

head

abdome n s e e mingl y consi sti n g of only two s e gments

a bdo m e n se e m i ngl y co nsi sti ng o f o nl y tw o se gm e nts

♂

head

♂

3 r d a nte nna l se gm e nt >2 × a s l o ng a s w i de surstyl us sm a l l

e pa ndri um a t to p be ndi ng i nwa rds a nd na rro w i ng

♂

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Common Bighorn Fly Pelecocera tricincta IDENTIFICATION 4–7 mm. Small hoverfly with orange bands or spots on abdomen. Facial tubercle and especially mouth edge protruding forwards; antennae unique among hoverflies covered in this book: arista very short and thickened, attached on outer top corner of very large third antennal segment, pointing forwards. Abdomen with orange undusted bands, which are sometimes reduced to pairs of spots. Male: eyes widely separated. SIMILAR SPECIES Reminiscent of Platycheirus and Melanostoma species but is distinguished by combination of small size, special antennae and strikingly different shape of face. Easily differentiated from other Pelecocera by arista being attached in outer top corner of third antennal segment; furthermore, sometimes with bands on abdomen, instead of pairs of spots usually found in other Pelecocera. OCCURRENCE Locally often in large numbers, with many flies on the same flowerhead. ECOLOGY Dry pine forest and in the transition zone of dry pine forest to heath or unimproved grassland, although in Great Britain

more associated with wetter habitats such as wet heath and mire. Mainly found on yellow composites including Catsear and Canadian hawkweed, sometimes also on flowering Common heather. Larval biology unknown, but clearly linked to pine forest as are other Pelecocera, and possibly with pine-associated fungi. COMMENT Like other Pelecocera, easily missed owing to very small size. Often detected by sweeping in sparse grassy vegetation at the edge of pine forest.

Mugwort Galleater Triglyphus primus IDENTIFICATION 5–6 mm. A small shiny black fly with flat face. Face entirely covered in dense long drooping white hairs; face flat and mouth edge weakly protruding; third antennal segment ovate, brown–black in male, red–brown in female. Legs black, but extreme tip of femora, base of tibiae and tarsomere 1 of mid and sometimes fore tarsus orange. Abdomen unique: seemingly consisting of only two segments because tergite 4 strongly reduced, when viewed from above, only tergites 2 and 3 well visible; especially striking in male, in female tergite 4 can be up to half the length of tergite 3. Male: without long spine on mid coxa or hind trochanter; sometimes outer half of wing dark. Female: frons convex, without indentation. SIMILAR SPECIES Always easily separated from all other species of key 3A (tribe Pipizini) by short abdomen with strongly reduced tergite 4, resulting in only two readily visible tergites; if this character is missed, can be confused with Neocnemodon, but males without long spine on mid coxa and hind trochanter, and females have frons without indentation. OCCURRENCE Widespread and scarce, but recognising its

habitat helps greatly to find it. ECOLOGY Mugwort-rich habitats including brownfield land, rough grassland, along railways, embankments and rivers. Has erratic flight and flies low through vegetation. Favours white flowers such as Wild carrot and hogweed. Larva lives in galls of the aphid Cryptosiphum artemisiae on Common mugwort.

Broad Flatface Pipizella divicoi IDENTIFICATION 6–7 mm. Fairly large, wide Pipizella; males can

be identified with certainty only by examining genitalia. Face flat, without facial tubercle; third antennal segment long, at least twice as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Sternites 3 and 4 flat. Male genitalia: teeth at tip of aedeagus cockscomb-shaped (not illustrated); epandrium large and more or less square, widening up to twothirds of length, whereafter bending inwards and narrowing, on top of each shoulder with a small surstylus; genitalia large, therefore sternites 3 and 4 small. SIMILAR SPECIES Differs from Trichopsomyia species by bare anterior anepisternum; from Neocnemodon and Pipiza by longer third antennal segment. Like many other Pipizella, male can be identified only by examining genitalia. Genitalia striking due to very large epandrium with wide flattened shoulders bending inwards including small surstylus on top. Females cannot be differentiated from congeners. OCCURRENCE A rather widespread species in Central Europe but in region covered in this book confined to warm (chalk) grasslands

in the south. Not known from Great Britain. ECOLOGY Chalk grasslands, grassy old quarries. Flies low and quickly above the ground and visits low flowers including Spring cinquefoil and Cypress spurge. COMMENT Genitalia remarkably hard to dissect.

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♀

♀

hi n d ti b i a

head

w i th sho rt ha i rs

♂

3 r d a nte nna l se gm e nt 1 . 5 – 2 × a s l o ng a s w i de

e pa ndri um a rm s l o ng

g ra d ua l l y wi d eni ng

♂

♂

surstylus lateral

♀

g e n i ta l i a

♀

h i n d ti b i a

head

w i th l o ng ha i rs

♂

3 r d a nte nna l se gm e nt >2 × a s l o ng a s w i de

♂ ba se wi d e, ti p n a rro w

♂

g e n i ta l i a

e pa ndri um a rm s a bse nt

surstylus lateral

♀

ta rsu s

♀

head

♂ ye l l o w

le gs e xte ns ive ly ye llow 3 r d a nte nna l se gm e nt 3 × a s l o ng a s w i de surstyl us v e ry l a rge

♂

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Common Flatface Pipizella viduata IDENTIFICATION 5–7 mm. A small Pipizella. Face flat, without

facial tubercle; third antennal segment long, at least 1.5 times as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Hairs on hind tibia about 1.3–1.5 times as long as width of hind tibia. Sternites 3 and 4 flat. Male genitalia: epandrium elongated, convex, with flattened epandrium arms clearly present; surstylus convex curved, pointed at tip; surstylus in profile gradually widening. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Male: can be identified only by examining the genitalia; like P. virens but smaller, epandrium more elongated, with more distinct epandrium arms, surstylus without keel and in profile gradually widening from base to tip. Female: identification very difficult; for differences with P. annulata, see that species; differs from usually larger P. virens and P. maculipennis by having shorter third antennal segment and anterior surface of hind tibia with hairs not or barely longer than

width of hind tibia. OCCURRENCE Widespread and the commonest of the Pipizella in large parts of Europe. ECOLOGY Variety of habitats such as brownfield lands, unimproved grasslands, dunes, heath, forest edge and herb-rich open broad-leaved forests both on base-poor and base-rich soil. Flies low through vegetation. Visits a wide variety of flowers. Larva feeds on root aphids.

Hairy-legged Flatface Pipizella virens IDENTIFICATION 6–9 mm. A large Pipizella with elongated abdomen. Face flat, without facial tubercle; third antennal segment long, at least twice as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Hairs on hind tibia long, c. 1.8–2.2 times as long as width of hind tibia. Sternites 3 and 4 flat. Male genitalia: epandrium roughly square and not very convex; epandrium arms almost missing; tip of surstylus blunt, strongly thickened at base and with keel anteriorly; surstylus in profile much wider at base than tip. Female: usually with indistinct dark spot in wing and strongly elongated third antennal segment. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Male: can be identified only by examining genitalia; much like P. viduata but epandrium squarer, without distinct epandrium arms, surstylus larger, with keel, in profile with wide base and narrow tip. Like P. zeneggenensis; for differences, see that species. Female: identification very difficult. For differences with P. annulata, see that species; differs from P. viduata by longer third antennal segment and anterior

surface of hind tibia with hairs distinctly longer than width of hind tibia; very similar to P. maculipennis but third antennal segment slightly shorter and tergite 3 with pale hairs on axis. OCCURRENCE Restricted to the southern part of the range covered by this book. Two broods per year, with spring generation peaking somewhat later than P. viduata. ECOLOGY Well-drained broadleaved forests, unimproved meadows, brownfield sites and chalk grassland, especially where hogweed is abundant. More bound to forest compared to P. viduata. Males sit in the forest edge and females fly low and inconspicuously through the undergrowth along forest edges and tracks. Often visits white umbellifers. Larva probably feeds on root aphids.

Pale-legged Flatface Pipizella annulata IDENTIFICATION 6–8 mm. A somewhat shiny-bronze Pipizella

with golden hairs. Face flat, without facial tubercle; third antennal segment long, at least twice as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Hind tibia largely yellow at base and narrowly yellow at tip; tarsomeres 1 and 2 of fore and mid tarsi yellow. Sternites 3 and 4 flat. Male genitalia: epandrium convex and rounded, surstylus very large, wide and rounded at base and more or less translucent. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Male genitalia are bast way to identify it from other Pipizella: size and shape of surstylus differs from that of all other Pipizella. The largely yellow legs are a useful feature and can help to identify females: base of tibiae extensively yellow, tip of tibiae yellow as well; tarsomeres 1 and 2 of fore and mid tarsi yellow, brighter yellow and more contrasting with black parts compared to other Pipizella; also, female has very long and thin third antennal segment. OCCURRENCE Restricted to the southern

continental part of range covered by this book, but expanding northwards over the last two decades. Not known from Great Britain. ECOLOGY Forest clearings with tall herbs, embankments, warm tall-herb grasslands with hogweed, chalk grasslands. Sits on sunlit herbs and visits white umbellifers, often Wild carrot and Common hogweed. Larva probably feeds on root aphids.

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surstyl us a s l o ng a s e pa ndri um

♂

e pa ndri um sm a l l

g e n i ta l i a

♂

ste rn i te 4

♂

tw o tube rcl e s

♂

g e n i ta l i a

♂

ste rn i te s

tra nsv e rse e l e va ti o n

♂

w i ng da rke ne d

♂

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Dry Flatface Pipizella zeneggenensis IDENTIFICATION 6–7 mm. Face flat, without facial tubercle; third antennal segment relatively short, 1.5–2 times as long as wide. Wing: vein M1 perpendicular to R4+5. Male: eyes meeting over a small distance; abdomen mostly covered with pale hairs, tergites 2 and 3 with pale yellow hairs and a few black hairs on posterior margin, tergite 4 with yellow hairs, although in some specimens anterior margin with black hairs, in most other Pipizella abdomen more extensively covered with black hairs; sternites 3 and 4 flat; genitalia: surstylus large and epandrium strikingly small, so surstylus longer than epandrium; epandrium roughly square. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Male: easily identified by genitalia, with surstylus being as long as or longer than epandrium; only P. virens can approach this, but surstylus smaller and with keel and swelling at base, and abdomen more extensively covered with black hairs. Female: often cannot be identified with certainty, but

third antennal segment on average shorter compared to other Pipizella. OCCURRENCE Mainly Central European montane and submontane areas; locally abundant. In the area covered by this book, very localised in the south. Not known from Great Britain. ECOLOGY Well-drained chalk grasslands, old quarries, outside North-west Europe also in heathlands and forest clearings on well-drained soil. Flies fast and very low through sparse vegetation and visits both low and high grassland flowers, including Cypress spurge and Common hogweed. Larval biology unknown.

Tubercled Flatface Pipizella pennina IDENTIFICATION 6–7 mm. Face flat, without facial tubercle; third antennal segment long, at least twice as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Male: sternite 4 with two tubercles; genitalia: large, epandrium widest near top, creating wide shoulders, shoulders not flattened or bent inwards; surstylus relatively small. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Males can be identified without examining genitalia: the only Pipizella with two tubercles on sternite 4; genitalia characteristic as well, with epandrium having wide shoulders with small surstyli on them, similar to P. divicoi but shoulders not flattened and bent inwards as in that species. Females cannot be distinguished from other Pipizella. OCCURRENCE A rare and localised species in area covered by this book. Not known from Great Britain. ECOLOGY Forest clearings, forest edges and forest with open canopy on chalk. Flies low along forest edges and bushes and visits mainly white umbellifers. Larval biology unknown.

Smudge-winged Flatface Pipizella maculipennis IDENTIFICATION 6–7 mm. A slender Pipizella with distinct dark spot on wing. Face flat, without facial tubercle; third antennal segment long, often three times as long as wide. Anterior anepisternum bare. Wing: vein M1 perpendicular to R4+5. Male: sternite 3 with transverse elevation; genitalia: epandrium small and rounded, surstylus bent inwards and anteriorly with distinct keel on basal part. SIMILAR SPECIES Identified as a Pipizella by elongated third antennal segment, bare anterior anepisternum and vein M1 perpendicular to R4+5. Male: relatively easily identified given transverse elevation on sternite 3; in combination with dark wing, this species can thus be identified in the field. A dark wing cloud can also be present in other Pipizella, especially in P. virens, and is not sufficient for identification. Genitalia reminiscent of P. virens or P. zeneggenensis, but epandrium more rounded. Female: identification very difficult. For differences with P. annulata and P. viduata, see those species. Very similar to P. virens but third antennal segment slightly longer and tergite 3 usually with black hairs on axis. OCCURRENCE In the range covered

by this book, confirmed only in Great Britain. ECOLOGY Lowgrowing vegetation in warm situations: warm grasslands, grass heaths and dry open spots in forest. Visits flowers, including umbellifers and thistles. Larva is probably a predator of rootdwelling aphids.

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♀

a b d o me n

♂

a bdo m e n sho rt a nd w i de

a nte nna e i nse rte d l o w o n he a d

und ers id e hind fe mur

wi th o ut groo ve and ri dge s

♂

head

♂

face

♂ f a ce w i de

♀

♂

face

g enit alia f a ce w i de

p rotrusi o n p resen t

da rk

♀

f o re ta rsu s

abdomen

♂

face

♂

♀

♂

g enit alia

♀

♂

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a b d o me n

no t swo l l en

protrusi o n a bsent

hind f emur

face

ye l l o w

te rgi te 5 l o ng

f o re ta rsu s

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Four-spotted Pithead Pipiza quadrimaculata IDENTIFICATION 5–8 mm. A short wide Pipiza. Face flat, without

facial tubercle; frons protrudes conically forward at level of antenna attachment. Antennae attached relatively low, halfway down head in side view. Third antennal segment wider than long, pale brown below. Anterior anepisternum bare. Wing: transparent, sometimes slightly evenly dark. All tarsomeres of fore tarsus dark; tip of hind femur below without groove and ridges; hind femur not swollen. Abdomen short and wide, almost always with pairs of spots on tergites 2 and 3. Male: tergite 4 more than twice as wide as long; genitalia: surstylus with protrusion at the base. Female: dust spots on frons indistinct or absent; scutum with short yellow hairs. SIMILAR SPECIES Short wide abdomen with usually two pairs of spots is a useful first feature in the field. The low-attached antennae distinguish it from all other Pipiza species. Third antennal segment pale below, hind femur not thickened and without groove and ridges below at tip, characters shared only with P. accola and P. luteitarsis; differs from these species,

besides low-inserted antennae, by presence of pair of spots on tergite 3, males have tergite 4 more instead of less than twice as wide as long and females have dust spots on frons indistinct or absent instead of clearly present. OCCURRENCE Has drastically decreased in Belgium and the Netherlands, possibly as a result of the changing climate and droughts. Not known from Great Britain. ECOLOGY Wet coniferous and mixed forests. Along forest tracks and in forest glades, often in partial shade and near water. Strong affiliation with buttercup. Larva possibly preys on aphids.

Broad-faced Pithead Pipiza accola IDENTIFICATION 7–9 mm. A Pipiza with strikingly wide face. In both sexes, face at level of antennae wider than an eye; frons protrudes conically forward at level of antenna attachment; third antennal segment oval, wider than long and usually pale below. Scutum usually with yellow hairs; anterior anepisternum bare. Tip of hind femur below without groove and ridges; hind femur not swollen; usually all tarsomeres of fore tarsus dark. Abdomen with pair of spots on tergite 2. Male: frons swollen; eyes meeting at obtuse angle, 100–110°; sides of face below antenna attachment parallel; genitalia: surstylus with protrusion at base and base at inner side covered with sturdy pale bristles. Female: tergite 5 approximately twice as wide as long. SIMILAR SPECIES With P. quadrimaculata and P. luteitarsis, only Pipiza in region covered by this book that has hind femur not swollen and tip below without groove and ridges. For differences with P. quadrimaculata, see that species. Much like P. luteitarsis, but usually tarsi darker, sides of face parallel in male and genitalia with protrusion at base of surstylus, this base at inner side covered with sturdy pale bristles; female has tergite 5 about two times as wide as long

instead of roughly as long as wide. OCCURRENCE A species of north-eastern Europe, but steadily spreading over North-west Europe. Not known from Great Britain. ECOLOGY Alluvial forest and alder carr or any other forest with an abundance of Bird cherry. Visits flowers of Bird cherry, Blackthorn and willow. Larval ecology not known, but very likely associated with Bird cherry. COMMENT The recently described Pipiza luteibarba is known from a historical record in northern France; much like P. accola and P. luteitarsis but third antennal segment 1.5 times longer than wide; males have fore tarsus yellow and pale hairs on face, and females have tergite 5 wider than long.

Pale-footed Pithead Pipiza luteitarsis IDENTIFICATION 7–9 mm. A rather slender, pale-haired Pipiza

with pale middle and fore feet. Frons protrudes conically forward at level of antenna attachment; third antennal segment slightly longer than wide or as long as wide and usually pale below. Anterior anepisternum bare. Wing: transparent or with light brown tint, no central spot. Hind femur not swollen; tip of hind femur below without groove and ridges; fore tarsus almost always entirely yellow. Abdomen with or without (mostly males) pair of spots on tergite 2; scutum and abdomen largely covered with yellow hairs. Male: face mostly covered with black hairs; eyes meeting at a right angle; sides of face below antenna attachment diverging; genitalia: protrusion at base of surstylus absent. Female: tergite 5 about as long as wide. SIMILAR SPECIES Combination of hind femur not swollen, yellow body hairs and yellow fore tarsus is diagnostic. With P. quadrimaculata and P. accola, the only Pipiza in region covered by this book that has hind femur not swollen and tip below without groove and ridges; for differences with P. quadrimaculata, see that species; usually differs from P. accola

by having tarsi yellow, but this character can be variable; for other characters, see P. accola. Males differ from similar species by lacking protrusion at base of surstylus. P. festiva has fore tarsus yellow as well; however, that species has hind femur swollen and tip below with groove and ridges, and wing with dark spot. OCCURRENCE Widespread, in low numbers but rather frequent in suitable habitat. ECOLOGY Near broad-leaved forests, half-open habitats with hedgerows, parks, probably needs elm nearby. The only Pipiza in which males hover in groups, 1.5–3 metres above the ground. Often sits on leaves and visits blossoms. Larva feeds on leaf-curl aphids on elm.

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♀

♂

a b d o me n

spo ts o f te n co nne cte d

da rk spo t

♂

f o re ta rsu s hind fem ur

ye l l o w

swol l en

♀ ♂

♂

a b d o me n

a bdo m e n w i de st be tw e e n te rgi te s 2 a nd 3

g enit alia

♀

sm a l l sp o ts

ste rn i te s

ste rni te 3 ye l l o w

1.0–1.2mm

♀

a b d o me n

♂ da rk spo t a bdo m e n usua l l y w i tho ut spo ts

♀

w ing di sti n ct da rk spo t

♀

♂

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Poplar Pithead Pipiza festiva IDENTIFICATION 8–10 mm. A Pipiza with yellow hairs, and female

with large yellow connected spots on tergite 2. Frons protrudes conically forward at level of antenna attachment; third antennal segment almost 1.5 times longer than wide, and black. Anterior anepisternum bare. Wing: with dark spot in middle. Hind femur swollen and below at tip with groove and ridges; fore tarsus yellow. Abdomen with golden-yellow hairs; tergite 2 with pair of spots, connected in female and often absent in male. Male: face narrow, with parallel sides. Female: spots on tergite 2 large, often fused to a band; tergite 3 often with pair of small round spots near posterior corner of tergite; sternite 3 dark or only upper half yellow. SIMILAR SPECIES Not too difficult to identify: combination of yellow fore tarsus and swollen hind femur is diagnostic. Shares yellow fore tarsus with P. luteitarsis but that species lacks dark spot on wing, hind femur not swollen and third antennal segment usually pale below. Like P. fasciata, but fore tarsus entirely yellow, wing with distinct dark spot, third

antennal segment longer and face in male with parallel sides. OCCURRENCE Essentially a southern species in Europe, occurs as far north as the lowland areas in Belgium and the Netherlands. ECOLOGY Poplar plantations, broad-leaved alluvial forest, city parks with Black poplar, half-open habitats with rows of poplar. Flies quickly around trees and bushes. Visits flowers such as Cow parsley and hogweed and settles on the leaves. Larva feeds on gall-making aphids on poplars.

Square-spot Pithead Pipiza fasciata IDENTIFICATION 9–10.5 mm. A rather large, variable, often four-spotted Pipiza. Frons protrudes conically forward at level of antenna attachment; third antennal segment roughly as long as wide or slightly longer than wide. Anterior anepisternum bare. Wing: transparent or in female with indistinct dark spot. Fore tarsus usually with basal three tarsomeres pale, but always apical tarsomere dark; hind femur swollen and below at tip with groove and ridges. Tergite 2 always with pairs of large yellow rectangular spots; tergite 3 with distinct or indistinct stripe-shaped pair of spots on posterior half. Male: face with pale hairs, sometimes black hairs intermixed; sides of face divergent; eyes meeting at an angle of c. 90–95°; fore tibia usually partly yellow; sides of tergites with white–yellow hairs; genitalia: large and slender, epandrium 1.0–1.2 mm long. Female: abdomen widest between tergites 2 and 3; usually tergite 4 without black hairs anteriorly, seldom with a single row of black hairs; pale hairs on abdomen white; sternite 3 predominantly yellow. SIMILAR SPECIES Like P. festiva but outer tarsomere of fore tarsus dark, body hairs white not golden, spot in wing absent or

indistinct, third antennal segment shorter and male with sides of face divergent. Like P. noctiluca and P. notata, but usually with pair of spots on tergite 3, male with larger and slenderer genitalia and face more extensively covered with white hairs and female with yellow sternite 3, wide abdomen and tergite 4 predominantly with white hairs. OCCURRENCE Distribution poorly known because of frequent misidentifications, but likely widespread and scarce. ECOLOGY Alluvial broad-leaved forests, old poplar plantations. Often sits on leaves of bushes. Larval biology unknown. COMMENT Until recently, mainly known under the name P. fenestrata; now confirmed as a valid species by genetic research but with different name.

Big-thighed Pithead Pipiza austriaca IDENTIFICATION 8–10 mm. A dark robust Pipiza. Frons protrudes

conically forward at level of antenna attachment; third antennal segment about as long as wide, black. Anterior anepisternum bare; scutum with white hairs. Wing: with dark spot in middle, better developed in female than in male, outer boundary diffuse, inner boundary sharp, in living specimens with blue sheen. Hind femur swollen and tip below with groove surrounded by two ridges and additional swelling; knees of fore and mid legs pale; fore tarsus dark. Abdomen usually entirely black, seldom with pair of narrow spots on tergite 2. Male: eyes meeting at an obtuse angle, 100–115°; side margin of tergite 1 with white hairs. SIMILAR SPECIES Often, Pipiza species with conspicuously swollen hind femur are misidentified as P. austriaca. However, P. austriaca has a diagnostic extra swelling below, at tip. Combination of extra swelling on hind femur, abdomen usually entirely black and wing with distinct dark spot characteristic. In male, white hairs on side margin of tergite 1 distinguishes it from P. noctiluca and P. notata. Combination of dark spot on wing and black

abdomen reminiscent of P. lugubris but hind femur with extra swelling at tip and third antennal segment shorter and darker. OCCURRENCE Widespread but local and in low numbers, recently decreasing on the continent. ECOLOGY Lush meadows (especially where buttercups are abundant), woodland rides and clearings. Flies through tall-herb vegetation and around bushes, and visits buttercups and white umbellifers. Larva feeds on aphids on, for example, hogweed.

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♂

♂

head

d i sti nct da rk spo t

ha i rs pa rtl y pa l e

♀

♂

♀

abdome n

head

hind fem ur

3 r d a nte nna l se gm e nt 1 . 5 × a s l o ng a s w i de

♀

a b d o me n

♂

head

♂

ha i rs m a i nl y bl a ck with or without s pots

♀

head

0.5–0.65mm

♂

genitalia 3 r d a nte nna l se gm e nt sho rt

♀

a b d o me n

♂

with or without s pots

♂

hind fem ur 0.7–0.9mm

♂

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g e n i ta l i a

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Smudge-winged Pithead Pipiza lugubris IDENTIFICATION 7.5–9 mm. A dark fairly small Pipiza. Frons

protrudes conically forward at level of antenna attachment; third antennal segment about 1.5 times longer than wide; third antennal segment brown–black. Anterior anepisternum bare. Wing: with dark, sharply defined spot, usually better developed in female than in male. Hind femur swollen and below at tip with groove and ridges; fore tarsus usually with inner 2–3 tarsomeres pale, outer tarsomeres always black. Abdomen black, sometimes with pair of indistinct yellow spots on tergite 2. Male: hairs on face partly pale; scutum, scutellum and abdomen largely covered with white hairs; sides of tergite 1 with white hairs. Female: tergite 4 largely covered with white hairs. SIMILAR SPECIES Hind femur swollen, wing with distinct dark patch, apical tarsomeres of fore tarsus black and abdomen dark with, at most, pair of small spots on tergite 2, a combination of characters that can also be found in P. austriaca and rarely in P. noctiluca and P. notata. Third antennal segment is c. 1.5 times longer than wide and

usually brownish, instead of shorter and black in other three; lacks extra swelling on hind femur of P. austriaca. Male has sides of tergite 1 with white hairs, versus black in P. noctiluca and P. notata; female has tergite 4 largely covered with white hairs, versus anteriorly with a band of black hairs in P. noctiluca and P. notata. OCCURRENCE Widely distributed over the range covered by this book but absent from northern Great Britain; occurs in low numbers. ECOLOGY Damp broad-leaved forests, mozaic landscapes with scrub, hedgerows and grasslands, and tall-herb vegetation. Flies up to several metres above the ground around trees and settles on leaves. The only Pipiza in region covered by this book in which the males hill-top. Visits flowers, mainly white umbellifers. Larval biology unknown.

Little Pithead Pipiza notata IDENTIFICATION 5–10 mm. An as-yet poorly understood Pipiza,

similar to P. noctiluca. Frons protrudes conically forward at level of antenna attachment; third antennal segment about as long as wide, black. Anterior anepisternum bare. Wing: transparent or with indistinct black spot, darkness of spot depending on sex and age (increases with ageing). Hind femur swollen and below at tip with groove and ridges; outer tarsomeres of fore tarsus black, inner tarsomeres yellow or black. Abdomen black or with pair of spots on tergite 2. Male: hairs on face black; side margin of tergite 1 mostly or entirely with black hairs. Female: tergite 4 anteriorly with band of black hairs, occupying about one-quarter of tergite length. SIMILAR SPECIES Extremely similar to P. noctiluca; for differences, see that species. Like P. austriaca, but without extra swelling at tip of hind femur, patch on wing less distinct or absent, and in male sides of tergite 1 with black hairs. Like P. lugubris (which has somewhat different phenology), but third antennal segment shorter and darker, sides of tergite 1 with black hairs in male, and female has tergite 4 anteriorly with band of black hairs. Like P. fasciata but tergite 3 black, male with smaller genitalia and

face with black hairs and female with sternite 3 black and with black band of hairs at anterior of tergite 4. OCCURRENCE Owing to extreme difficulty in identifying, and recent redefinition, it is still unknown whether there are ecological differences with P. noctiluca. Possibly with slightly earlier flight season and found more in vicinity of forests. ECOLOGY Forests and forest edges. Sits on leaves 1–3 metres above the ground and visits flowering bushes and herbs. Larva feeds on leaf-rolling aphids. COMMENT Until recently, known under the name P. bimaculata.

Common Pithead Pipiza noctiluca IDENTIFICATION 5–10 mm. An as-yet poorly understood and seemingly very variable Pipiza, similar to P. notata. Frons protrudes conically forward at level of antenna attachment. Third antennal segment about as long as wide. Wing: usually with black spot, vaguely delimited. Hind femur swollen and below at tip with groove and ridges; outer tarsomeres of fore tarsus black, inner tarsomeres yellow or black. Abdomen black or with pair of spots on tergite 2. Male: sides of tergite 1 largely or entirely with black hairs. Female: tergite 4 anteriorly with band of black hairs, occupying about one-quarter of tergite length. SIMILAR SPECIES For differences with Pipiza other than P. notata, see that species. Extremely similar to P. notata. Recent research shows that previously reported differences between these species like punctation on abdomen, colour of tarsi and spot on wing are unreliable. Unfortunately, with current knowledge certain identification seems to be possible only by using DNA or complex wing formulas. Tentative characteristics are: on average, P. noctiluca dark wing spot more distinct and male genitalia larger.

It remains unclear how these differences should be interpreted in region covered by this book; in the meantime, identification of the two species remains problematic if not impossible. OCCURRENCE See P. notata. ECOLOGY See P. notata. COMMENT For all Pipiza species, spots on the wing become more obvious with age: spot barely discernable in recently emerged specimens, in older specimens, the spot becomes darker.

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Pale-footed Psyllid-killer Trichopsomyia flavitarsis IDENTIFICATION 5–6 mm. A small black Trichopsomyia usually

found at ground level. Face flat, not inflated; face at level of antennae not wider than an eye; third antennal segment about three times longer than wide. Anterior anepisternum with hairs. Wing: vein M1 perpendicular to R4+5. Mid tarsus with basal two tarsomeres yellow. Male: scutum with black and white hairs; genitalia with surstylus very narrow, inner side with a small protrusion halfway. Female: frons without dust spots; occiput dusted pale grey below; hind tibia black and with some hairs being longer than width of hind tibia; tarsomere 2 of hind tarsus yellow; tergite 2 with two small round yellow or orange spots, sometimes hardly visible, diameter of the markings smaller than distance between inner extremities of markings. SIMILAR SPECIES Compared to similar genera of the Pipizini (the species in key 3A), only Trichopsomyia has hairs on anterior anepisternum, although these black hairs can be very hard to detect on the black background. Male: among species

of Trichopsomyia, recognised by combination of long third antennal segment and vein M1 perpendicular to R4+5. Female: in Trichopsomyia, easily recognised by small round spots on tergite 2, spots absent in T. joratensis and spots larger in T. lucida; Pipiza can have pair of spots on tergite 2 as well, but they have third antennal segment much shorter, frons protruding conically forward and usually spots less round. OCCURRENCE Very localised, rarely seen away from habitat. ECOLOGY Wet heathlands, humid unimproved grasslands with flushes, base-poor mires and wet meadows, but can also occur in base-rich meadows with large stands of smaller rushes. Flies low through low vegetation. Males hover 1–2 metres above the ground near bushes or sit on leaves. Visits flowers, often of Common tormentil. Larva found in the galls of the psyllid bug Livia juncorum on several rush species.

Large-spotted Psyllid-killer Trichopsomyia lucida IDENTIFICATION 5–6 mm. A small black Trichopsomyia. Face

flat, not swollen and at level of antennae not wider than an eye; third antennal segment about twice as long as wide. Anterior anepisternum with hairs. Wing: vein M1 ends at a sharp angle to R4+5. Mid tarsus with basal two tarsomeres yellow. Male: scutum entirely covered with black hairs; surstylus of genitalia narrow and hollowed out on inner side. Female: frons with pair of triangular dust spots; occiput dusted pale grey below; hind tibia with silver–white hairs, some hairs longer than width of hind tibia; tergite 2 with pair of trapezoid to triangular spots with rounded corners, diameter of markings larger than distance between inner extremities of markings. SIMILAR SPECIES Always recognised as Trichopsomyia by hairs on anterior anepisternum. Male: like Heringia heringi but mid tarsus with basal two tarsomeres bright yellow; like T. joratensis but face narrower and third antennal segment longer; like T. flavitarsis but vein M1 ends at a sharp angle to R4+5 and third antennal segment shorter. Female: stands out by pair of spots on tergite 2, spots larger than in T. flavitarsis; spots like in Pipiza, but usually smaller, hind femur not thickened,

frons not protruding conically forward and anterior anepisternum with hairs. OCCURRENCE An elusive species, possibly to a large extent arboreal. Found in England in 2006. ECOLOGY Alluvial broad-leaved forest, forest glades, forest tracks, forest edges. Usually in forests with poplar or elm. Visits, among others, white umbellifers including Cow parsley and hogweed. Larval biology unknown, but possibly feeds on psyllid bugs on poplar.

Obscure Psyllid-killer Trichopsomyia joratensis IDENTIFICATION 7–8 mm. A fairly large black Trichopsomyia. Most notable character is inflated frons and wide face: at level of antennae about 1.5 times wider than an eye; third antennal segment slightly longer than wide, red–brown and pale below. Anterior anepisternum with hairs. Wing: vein M1 ends almost perpendicular to R4+5. Mid tarsus with basal one or two tarsomeres yellow; hind leg black except for yellow knee. Male: scutum entirely covered with black hairs; wings dark brown; genitalia with surstylus very wide, not constricted on apical half. Female: occiput shiny black, without pale grey dusting; frons without dust spots; hairs on hind femur mostly black and shorter than width of hind tibia. SIMILAR SPECIES Could be mistaken for a Neocnemodon or Pipiza owing to short third antennal segment but anterior anepisternum with hairs; hind femur not swollen and frons not protruding conically forward like Pipiza. Moreover, differs from Neocnemodon by vein M1 ending almost perpendicular to R4+5 and male lacks long spine on mid coxa and hind trochanter. Identified in Trichopsomyia by short third

antennal segment; wide, inflated face; and female by all-black abdomen and shiny occiput. OCCURRENCE In region covered by this book, mostly in mountain ranges. Not known from Great Britain. ECOLOGY Coniferous and mixed forests, mainly spruce plantations. Often visits the flowers of hawthorn and white umbellifers. Flies low through vegetation and drinks at wet tracks. Larval biology unknown, but pupa found on spruce.

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g enit alia surstyl us sh o rt a nd wi d e

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hind trochanter

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g enit alia s urstyl u s l ong and sl en der

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sternites tu bercl e

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Dark Spikeleg Neocnemodon pubescens IDENTIFICATION 5–7 mm. A deep black Neocnemodon. Frons not

conically protruding forwards; third antennal segment pale below and, at most, 1.5 times longer than wide. Anterior anepisternum bare. Wing: vein M1 ends at a sharp angle to R4+5; cell bm and cell br entirely covered with microtrichia. Male: face mostly covered with black hairs; sides of thorax, scutellum and usually also scutum largely covered with black hairs; mid coxa and hind trochanter with long spine; underside of tarsomere 1 of fore tarsus with depression, which is easily missed since it is same yellow colour as rest of tarsomere; mid tibia swollen; wings often slightly dark; sternites flat; genitalia: surstylus short and wide. Female: frons usually entirely shiny. SIMILAR SPECIES Recognised as a Neocnemodon by combination of bare anterior anepisternum, short third antennal segment, frons not conically protruding forwards and male by mid coxa and hind trochanter with long spine. Male: modifications on legs not unlike in N. vitripennis, but scutum largely with black hairs and cell bm and cell br entirely covered with microtrichia. Female identified with difficulty, mainly confused with N. verrucula owing to cells bm and br entirely covered with microtrichia, but hairs on eyes supposedly denser and darker. OCCURRENCE Widespread and frequent where coniferous forests are found, can be very abundant near large spruce plantations. ECOLOGY Coniferous forests, both pine, spruce and larch. Sits on leaves of trees and bushes at forest edge. Visits flowers of several species. Presumably largely arboreal but comes down to drink on moist forest tracks. Larval biology unknown, but probably related to coniferous trees.

Warted Spikeleg Neocnemodon verrucula IDENTIFICATION 5–6 mm. Small and slender Neocnemodon.

Frons not conically protruding forwards; third antennal segment short, at most 1.5 times longer than wide; third antennal segment pale below. Anterior anepisternum bare. Wing: vein M1 ends at a sharp angle to R4+5; cell bm and cell br entirely covered with microtrichia. Male: frons slightly swollen, face relatively wide, head proportionally large compared to body; scutum and scutellum usually largely with white hairs; mid coxa and hind trochanter with long spine; tarsomere 1 of fore leg normal shape; lower half of mid tibia slightly distorted but not clearly swollen; tergites 2–4 mostly with white hairs; sternite 4 with distinct tubercle in middle; genitalia: surstylus long and narrow. Female: hairs on eyes pale, sparse and indistinct; frons entirely shiny, at most with dust spots not larger than an ocellus; posterior hairs of hind tibia shorter than width of hind tibia. SIMILAR SPECIES To identify this species as a Neocnemodon, see N. pubescens. Males identified in Neocnemodon by tubercle on sternite 4; moreover, differs from N. vitripennis by normally shaped tarsomere 1 of fore tarsus, smaller and slenderer body, wing base entirely covered with microtrichia and tergites 2–4 largely with white hairs. Female: identified with difficulty, but only N. pubescens also with cell bm and cell br entirely covered with microtrichia, but that species should have denser and darker hairs on eyes. OCCURRENCE England and Belgium are on the southern limit of its distribution. A widespread but rare Neocnemodon, typically found in low numbers. ECOLOGY Coniferous and mixed forests. Like other Neocnemodon, regularly drinks along wet forest tracks. In spring, mainly on late flowering willows such as Eared willow and Creeping willow, but also on Field maple. Larval biology unknown. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 2 8 7

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wing detail

ha i rs pa l e

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Pale-haired Spikeleg Neocnemodon vitripennis IDENTIFICATION 6–7 mm. Frons not conically protruding forwards; third antennal segment short, at most 1.5 times longer than wide; third antennal segment pale below; face mainly covered with black hairs. Scutum largely covered with pale hairs; anterior anepisternum bare. Wing: vein M1 ends at a sharp angle to R4+5; at least half of cell bm and cell br without microtrichia. Sternites flat, without tubercles, shiny. Male: mid coxa and hind trochanter with long spine; underside of tarsomere 1 of fore tarsus with depression; lower half of mid tibia distorted; genitalia: surstylus long and with strong incision. Female: frons entirely shiny, at most with dust spots not larger than an ocellus; frons with black hairs, at most with a narrow band of white hairs before ocellar triangle; eyes with dense white hairs; occiput relatively narrow when viewed from above; posterior hairs of hind tibia as long as or longer than width of hind tibia. SIMILAR SPECIES For identification as a Neocnemodon, see N. pubescens. Male: modifications on fore and mid legs quite similar to N. pubescens, also sternites without tubercles; however, that species has scutum largely covered with black hairs and cell bm and cell br entirely covered with microtrichia. Female: bare patches on wing and long hairs on hind tibia distinguish it from N. pubescens and N. verrucula; supposedly with less wide occiput than N. latitarsis and frons more extensively covered with black hairs than N. brevidens, but unclear how reliable these characters are. OCCURRENCE Widespread, except in coniferous forests; generally the commonest Neocnemodon species in North-west Europe. ECOLOGY Broad-leaved and mixed forests, but also open habitats with hedgerows, parks and gardens. Males hover and sit on

leaves. Visits flowers, including white umbellifers. Neocnemodon species are often seen when they come down to drink in sheltered, partly shaded areas in the forest with low vegetation. Larva feeds on adelgids and coccids.

Big-ankled Spikeleg Neocnemodon latitarsis IDENTIFICATION 6–8 mm. A medium to large-sized jet-black

Neocnemodon. Frons not conically protruding forwards; third antennal segment short, at most 1.5 times longer than wide, pale below. Anterior anepisternum bare. Wing: vein M1 ends at a sharp angle to R4+5; at least half of cell bm and cell br without microtrichia. Male: hairs on scutum variable, ranging from largely black to white, ground colour jet black, often with purple undertones; mid coxa and hind trochanter with long spine; tarsomere 1 of fore tarsus swollen; mid tibia anteriorly with distinctive swelling; sternite 3 with distinct keeled tubercle in middle; genitalia: surstylus long and slender. Female: frons shiny, at most with dust spots not larger than an ocellus; frons largely with white hairs, only some scattered black hairs anteriorly and posteriorly; eyes with dense white hairs; occiput wide when viewed from above; posterior hairs of hind tibia as long as or longer than width of hind tibia. SIMILAR SPECIES For identification as a Neocnemodon, see N. pubescens. Male: in Neocnemodon, easily identified by tubercle on sternite 3 and swelling on mid tibia. Female: difficult or impossible to identify; bare patches in wing and long hairs on hind tibia distinguish it from N. pubescens and N. verrucula; supposed to have wider occiput compared to other Neocnemodon, but usefulness of this character unclear. OCCURRENCE Widespread but scarce. ECOLOGY Both broad-leaved and coniferous forests. Habitat association unclear, possibly associated with many different tree species, both broad-leaved and coniferous but more in coniferous forests. Flies low above the ground to drink and visits flowers or sits on sunlit leaves. Often visits brambles. Larva feeds on aphids on trees.

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a t l ea st ha l f of cel l bm a n d b r wi th o ut m i crotri chi a

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head

♂ 3 r d a nte nna l se gm e nt l o ng we ak cloud

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s harp angle

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♂ post- anal lamella heringi

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Poplar Spikeleg Neocnemodon brevidens IDENTIFICATION 7–8 mm. A rather large Neocnemodon with

white hairs. Frons not conically protruding forwards; third antennal segment short, at most 1.5 times longer than wide, pale below. Anterior anepisternum bare. Wing: vein M1 ends at a sharp angle to R4+5; at least half of cell bm and cell br without microtrichia. Male: scutum and face largely covered with white hairs; mid coxa and hind trochanter with long spine; tarsomere 1 of fore tarsus posteriorly with distinct tubercle with black top; tarsomere 1 of mid tarsus with deep incision with dark edge; outer side fore tibia with shiny black spot; mid tibia with swelling, covered with black setae; sternites flat. Female: frons entirely shiny, at most with dust spots not larger than an ocellus; frons largely with white hairs, at most with a narrow band of black hairs anteriorly and near ocellar triangle; eyes with dense white hairs; occiput relatively narrow when viewed from above; posterior hairs of hind tibia as long as or longer than width of hind tibia. SIMILAR SPECIES For identification as a Neocnemodon, see N. pubescens. Male identified in Neocnemodon by modifications on legs: tarsomere 1 of fore tarsus posteriorly with tubercle, tarsomere 1 of mid tarsus with deep incision with dark edge and mid tibia with swelling. Female: hard to identify; bare patches in wing and long hairs on hind tibia distinguish it from N. pubescens and N. verrucula; supposedly occiput less wide than in N. latitarsis and frons more extensively covered with white hairs than N. vitripennis, but unclear how reliable last two characters are. OCCURRENCE A scarce species, knowledge of its close association with poplar helps to find it. ECOLOGY Alluvial broad-leaved forests, poplar plantations, but also parks. Sometimes abundant in the

undergrowth of poplar plantations. Comes down to drink and visits white umbellifers, amongst others. Larva presumably preys on adelgids and coccids on poplar.

Dark-haired Smoothleg Heringia heringi IDENTIFICATION 5–9 mm. Medium-sized, jet-black species.

Frons not conically protruding forwards; third antennal segment 1.5–2 times as long as wide. Anterior anepisternum bare. Mid coxa and hind trochanter without long spine. Wing: usually with medial dark patch; vein M1 ends at a sharp angle to R4+5. Male: frons swollen; sternites normal shape, flat; all tarsi dark above, but often tarsomere 1 somewhat yellowish; genitalia: epandrium long and slender. Female: frons with wedge-shaped dust spots occupying over half its width. SIMILAR SPECIES Like Trichopsomyia species, especially T. lucida, but anterior anepisternum bare and in male epandrium much longer; moreover, mid tarsus dark or only tarsomere 1 dirty yellow. Like Pipiza and Neocnemodon, but third antennal segment longer, frons not conically protruding forwards like in Pipiza and male mid coxa and hind trochanter without long spine like in Neocnemodon. Like Pipizella, but gives a black rather than bronze impression, and vein M1 ends at a sharp angle to R4+5. OCCURRENCE Widespread in lowland areas, but in low numbers. ECOLOGY Alluvial broad-leaved forests, poplar plantations, alder and willow carr, often with willow and poplar. Flies low above or through vegetation along tracks, often in partial shade. Visits flowers such as hogweed and sits on leaves. Larva preys on gall-making or leaf-curling aphids or psyllids on various trees, including poplar, apple and elm. COMMENT Sometimes Longhorned Smoothleg H. senilis is recognised. Females difficult to identify, but males have scutum and legs with exclusively white hairs instead of some black hairs also, third antennal segment 2–2.5 times instead of 1.5–2 times longer than wide, and slight differences in genitalia. In the range covered by this book, these differences appear rather stable but elsewhere intermediates

occur. As H. senilis was described from the former Yugoslavia, it is unclear if this is the same taxon as H. senilis from North-west Europe, and whether it is a valid species at all. Further research is needed.

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head

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a bdo m en wi th da rk m a rg i ns

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se nso ry pi t sm a l l a nd ro und wi n g d e ta i l

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a b d o me n

a bdo m e n w i th da rk m a rgi ns fa ce sl i g htl y protrudi ng

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Aspen Logsitter Hammerschmidtia ferruginea IDENTIFICATION 10–12 mm. Large enigmatic orange–red hoverfly. Lower part of face protruding forwards; arista with long hairs; inner side third antennal segment with small oval sensory pit. Sides of scutum with large black bristles; both scutum and abdomen dark red–brown, but fresh specimens are paler. Wing: vein M1 ends perpendicular to R4+5. All femora thickened. Abdomen elongated. Male: face with facial tubercle. SIMILAR SPECIES Easy to be mistaken for something else than a hoverfly, looks like dung flies (Scathophagidae), Dryomyzidae or house fly relatives (Muscidae). Readily identifiable as a hoverfly by, for example, wing venation. Similar to Brachyopa species but larger, with more elongated abdomen and vein M1 ends perpendicular to R4+5; other differences with Brachyopa include black bristles on outer sides of hind tibia, part of vein R4+5 beyond vein M1 being longer than crossvein r-m and male with facial tubercle. OCCURRENCE In the range covered by this book, restricted to Scotland, but critically endangered. ECOLOGY Forests

with large Aspen stands. Adults visit assorted flowers including Rowan, Bird cherry, hawthorn, pear, buttercup and willow. Larva lives in sappy decay beneath the bark of recently fallen Aspen.

Greater Sapeater Brachyopa vittata IDENTIFICATION 8–11 mm. A large Brachyopa with red–brown thorax with pale longitudinal stripes. Lower part of face strongly protruding; arista with very long hairs, more than three times longer than width of arista at base; sensory pit small and round. Upper part of katepisternum with some pale long hairs; posterior margin of posterior anepisternum with 4–10 strong black bristles; posterior margin of scutellum with black bristles. Wing: long in proportion to body. SIMILAR SPECIES The only Brachyopa that can approach the size of Hammerschmidtia ferruginea; for differences, see that species. Similar to B. testacea, B. obscura, B. panzeri and B. dorsata owing to red–brown thorax, but larger and face protruding further forwards; moreover, differs from B. panzeri and B. dorsata by much longer hairs on arista; other differences with B. testacea and B. obscura include larger size, proportionally longer wings, upper part of katepisternum with some pale long hairs and anepisternum with 4–10 instead of, at most, 3–5 black bristles. OCCURRENCE Now common in large spruce plantations in the east and south of range covered by this book, but colonised since the end of last century. Not known from Great Britain. ECOLOGY Old

spruce plantations. Often to be found near felled trunks, but also regularly found on white umbellifers and flowering bushes. Larva has been found under the bark of several spruce species and larch.

Conifer Sapeater Brachyopa testacea IDENTIFICATION 6–8 mm. A small orange–red Brachyopa. Lower

part of face moderately protruding; arista with long hairs, three times longer than width of basal part of arista; sensory pit small and round. Thorax red–brown with pale dusted longitudinal stripes on scutum; lower part katepisternum with hairs, upper part bare; posterior margin of posterior anepisternum with, at most, 3–5 black bristles. Wing: cell dm in lower corner with extension one-tenth length of crossvein dm-m. Abdomen with a dark longitudinal stripe over middle of tergites; posterior margins of the tergites dark. SIMILAR SPECIES Similar to B. vittata, B. obscura, B. panzeri and B. dorsata owing to red– brown thorax; for differences with B. vittata, see that species; like B. panzeri and B. dorsata but slightly smaller, arista with longer hairs, upper part of katepisternum bare and scutum less grey on top; very similar to B. obscura but tergites 2–4 with darker markings, including dark margins and dark longitudinal stripe, although very pale specimens occur; other differences include hairs on arista being three instead of two times longer

than width of basal part of arista, further protruding face, on average slightly larger and extension in lower corner of cell dm shorter. OCCURRENCE Widespread on the continent. Can be abundant in spruce plantations. Not known from Great Britain. ECOLOGY Coniferous forests, including pine, larch but mainly spruce. Males hover near the base of trees and sit on or around freshly felled conifers. Visits white umbellifers and flowering bushes. Larva found exclusively in sap runs of coniferous trees.

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a bdo m e n pa l e head a bdo m e n pa l e

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wing detail

a b d o me n

a n te n n a

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se nso ry pi t l a rge

da rke ne d l i ngul a l o ng a nd na rro w

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head

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abdo me n

g e n i ta l i a

a n te n n a

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se nso ry pi t sm a l l tra nspa re nt

l i ngul a sho rt a nd w i de

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head

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g e n i ta l i a

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Pale Sapeater Brachyopa obscura IDENTIFICATION 5–7 mm. Small, quite slender and pale yellowbrown Brachyopa. Lower part of face slightly protruding; arista with long hairs, twice as long as width of base of arista; sensory pit small and round. Lower part katepisternum with hairs, upper part bare; posterior anepisternum in the upper posterior corner without or with, at most, 3–5 black bristles; scutum orange– brown. Wing: cell dm in lower corner with extension one-quarter length of crossvein dm-m. Abdomen entirely yellow–brown or orange–brown, sometimes with slightly dark posterior margins of tergites and without or at most with indistinct dark markings in middle of tergites. SIMILAR SPECIES Similar to B. vittata, B. testacea, B. panzeri and B. dorsata owing to red–brown thorax, but stands out in the field by combination of small size, orange scutum and pale, weakly marked abdomen. For differences with the much larger B. vittata, see that species. Unlike B. panzeri and B. dorsata, small, arista with longer hairs, upper part of katepisternum bare and scutum less grey

on top. Much like B. testacea; for differences, see that species.

OCCURRENCE Widespread but localised in Scandinavia, further

south in Europe only a handful small isolated populations. Not known from Great Britain. ECOLOGY Mixed or broad-leaved forests with Aspen or Black poplar. Males sit on herbs around sunlit tree bases of alder, poplar or Aspen in the forest or fly low around stems of Aspen. Visits flowers of hawthorn. Larva has been found under bark of a pear tree, but more likely is associated with Aspen or other poplars.

Beech Sapeater Brachyopa panzeri IDENTIFICATION 6–9 mm. A medium-sized, predominantly red–brown Brachyopa. Lower part of face distinctly protruding; arista with short hairs, hairs not much longer than width of arista at base; sensory pit large, especially in female, distance between lower margin of third antennal segment and sensory pit smaller than diameter of sensory pit itself. Thorax largely red–brown, usually scutum almost entirely or only in the centre dark grey–black, but at least side margins and area before scutellum red–brown; upper part of katepisternum with long pale hairs; scutellum without robust black bristles. Wing: wing-tip and false vein mostly dark. Abdomen with dark longitudinal stripe and dark posterior margins of tergites. Male genitalia: lingula long and narrow. SIMILAR SPECIES For differences with species other than B. dorsata, see that species. Much like B. dorsata but sensory pit larger, distance between lower margin of third antennal segment and sensory pit smaller than diameter of sensory pit itself, the other way around in B. dorsata; but note that, especially in males, size of sensory pit is variable and overlap exists; other characters include lack of black bristles on posterior

margin of scutellum, dark wing-tip and false vein and, in male, genitalia with lingula long and narrow instead of short and wide. OCCURRENCE Widespread in the east and south of the range covered by this book, but localised and in low numbers. Not known from Great Britain. ECOLOGY Typical species of large, old broad-leaved forests with veteran trees, often with beech. Males sit low near the ground or on twigs and herbs around felled trees, near stumps or at the base of trees. Visits white umbellifers but most often flowering bushes, such as Blackthorn, hawthorn and willow. Larva undescribed.

Smallpit Sapeater Brachyopa dorsata IDENTIFICATION 6–9 mm. A medium-sized, red–brown hoverfly. Lower part of face distinctly protruding; arista with short hairs, hairs not much longer than width of arista at base; sensory pit small, distance between lower margin of third antennal segment and sensory pit larger than diameter of sensory pit itself. Thorax largely red–brown, scutum especially in male usually extensively dark grey–black, with thick golden-brown or grey–brown dusting; upper part of katepisternum with long pale hairs; scutellum with robust black bristles. Wing: transparent, sometimes wing-tip slightly dark. Abdomen with dark longitudinal stripe and dark posterior margins of tergites. Male genitalia: lingula short and wide. SIMILAR SPECIES Keys out in the group of species with red–brown thorax, but be aware that in this species and B. panzeri, upper part of scutum can be quite grey, but sides of thorax and on scutum, at least side margins and area before scutellum, red–brown. In the group of species with red–brown thorax with B. panzeri, easily distinguished by short hairs on arista, much longer in especially B. vittata; furthermore, distinguished

from B. testacea and B. obscura by having hairs on upper part of katepisternum. Very similar to B. panzeri; for differences, see that species. OCCURRENCE Now fairly common in the eastern part of the range covered by this book, but did not arrive before the beginning of this century. Not known from Great Britain. ECOLOGY Old broad-leaved and coniferous forests. Flies around tree trunks or sap runs, or sits low on leaves or on the ground. Larva has been found in sap runs under bark or in tunnels of beetles in broad-leaved and coniferous trees.

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head

a b d o me n

a n te n n a

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Pale-shouldered Sapeater Brachyopa scutellaris IDENTIFICATION 6–8 mm. Brachyopa with a grey thorax and orange abdomen. Lower part of face moderately protruding; third antennal segment with large kidney-shaped sensory pit reaching lower margin of third antennal segment; arista with hairs, hairs about as long as width of arista at base. Thorax largely grey, scutum grey, contrasting with red–brown postpronotum and sides of anepisternum, contrast especially distinctive in female; scutellum entirely pale. Abdomen red–brown; posterior corners of tergite 2 with black hairs. SIMILAR SPECIES The red–brown postpronotum is a character for distinguishing this species from all other species with a grey scutum in the field; if this character is indistinct: combination of hairs on arista, large kidney-shaped sensory pit and black hairs on posterior corners of tergite 2 differentiates it from all other Brachyopa with a grey scutum. OCCURRENCE Often the most common Brachyopa in North-west European lowland broad-leaved forest, with B. pilosa. May occur in large numbers. ECOLOGY Broad-leaved forests, especially

common in alluvial forests with poplars in Low Countries but in Great Britain can occur in a variety of broad-leaved woodland types. Often flies in groups around the trunks of sunlit trees and sits on low vegetation nearby. Visits flowers of plants such as Cow parsley, Blackthorn, Cherry laurel, willow and hawthorn. Larva lives in sap runs under the bark of various broad-leaved trees.

Dark-shouldered Sapeater Brachyopa pilosa IDENTIFICATION 6–8 mm. Brachyopa with grey thorax and orange abdomen. Lower part of face moderately protruding; third antennal segment with small round sensory pit; arista with hairs, hairs about as long as width of arista at base. Scutum, including postpronotum, grey, also remainder of thorax grey; scutellum entirely pale. Abdomen red–brown; posterior corners of tergite 2 entirely or almost entirely with pale hairs. SIMILAR SPECIES Shares hairs on arista and grey scutum with B. scutellaris, but postpronotum grey, sensory pit much smaller and round. Like B. bicolor, but arista with long hairs and scutellum without transverse groove and without dusting in anterior part. Differs from B. insensilis, B. grunewaldensis and B. silviae by arista distinctly having hairs and distinct sensory pit. OCCURRENCE A widespread species on the continent, frequent and in large numbers. Often the most common Brachyopa in broad-leaved woodland. In Great Britain scarcer, and more strongly associated with either beech or Aspen woodland. ECOLOGY Favours broadleaved forests, both wet and dry, also in city parks and spruce forest. In Great Britain, seemingly associated with decaying

cambian layer beneath bark of recently fallen or felled trees such as beech and Aspen (can occur alongside Hammerschmidtia ferruginea in Scotland). Adults often congregate on fallen trunks. Usually hovers with several males around the trunk of sunlit trees and sits on nearby leaves. Visits flowers of, for example, Cow parsley, Blackthorn, willow and hawthorn. Larva lives in sap runs or decaying sap under the bark of broad-leaved trees.

Dark-saddled Sapeater Brachyopa bicolor IDENTIFICATION 6–9 mm. Brachyopa with grey thorax and orange abdomen. Lower part of face moderately protruding; arista almost bare, if hairs present they are much shorter than width of arista at base; sensory pit small, round or oval. Scutum including postpronotum grey, also remainder of thorax grey; notopleuron with dark hairs; anterior part of scutellum grey-dusted; scutellum with transverse groove, although not always distinct. Fore tarsus black; femora quite swollen. Abdomen red–brown, in female often with dark markings on posterior margins of tergites. SIMILAR SPECIES Robust species in Brachyopa with grey thorax with conspicuously swollen hind femur. Arista bare, but with hairs in B. pilosa and B. scutellaris; moreover, these two species lack the transverse groove and grey dusting on anterior part of scutellum, but be aware: transverse groove can be very indistinct. Like the trio B. insensilis, B. grunewaldensis and B. silviae, but third antennal segment with more distinct and larger sensory pit, fore tarsus black, notopleuron entirely covered with black hairs instead of mostly pale hairs, transverse suture shallower, scutellum

with transverse groove and vein M1 with deeper curve just before meeting crossvein dm-m. Indicative difference in the field with B. insensilis is that species with white and smooth dusting on scutum. OCCURRENCE Widespread but localised; one of the rarer species of the Brachyopa with grey thorax. ECOLOGY Mature broad-leaved forests and historical parklands, often with mature oak or beech, or else chestnut or elm. The flies usually congregate on trunks near sap runs and not on nearby low herbs, often at open sap runs and at 1–2 metres above the ground. Larva lives in sap runs of broad-leaved trees.

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se nso ry pi t a bse nt

a nte ri o r pa rt o f scute l l um gre y duste d

ve in M 1 wi th we ak be nd

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na rro w shi ny stri pe

head

v e rte x duste d hea d

thorax lateral

m e di o te rgi te duste d proepi m eron ba re

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a n te n n a

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a l m o st ba re ante rior part of s cute llum gre y du sted

se nso ry pi t a bse nt

w i de shi ny stri pe

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thorax lateral

head

b a c k sc u te l l u m

p roepi m eron h a i red

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Mealy Sapeater Brachyopa insensilis IDENTIFICATION 6–9 mm. Brachyopa with grey thorax and orange abdomen. Lower part of face moderately protruding; vertex dusted, space between ocelli dusted; sensory pit on third antennal segment absent or rudimentary if present; sensory pit can be visible in transmitted light, but is closed at the surface; arista bare, if hairs present, much shorter than width of arista at base; thorax grey, hairs on notopleuron pale; proepimeron bare; scutellum semicircular, anteriorly dark and with dense grey dusting; mediotergite dusted; abdomen red–brown. Fore tarsus almost entirely dark-brown to black. Female: frons with shiny undusted longitudinal stripe, at level of front ocellus not wider than ocellus itself; tergite 2 entirely covered with pale hairs. SIMILAR SPECIES For differences with Brachyopa other than B. grunewaldensis, see that species. Much like B. grunewaldensis; reliable differences are dusted mediotergite and bare proepimeron; other differences include ocellar triangle and vertex dusted versus partly shiny in B. grunewaldensis, scutellum semicircular instead of trapezoidal, fore tarsus darker and lower part of face rather strongly protruding. OCCURRENCE Has strongly benefited from the spread of bleeding canker among Horse chestnut over the past decades. Now widespread and often in urban areas. ECOLOGY Mature broad-leaved forests but nowadays often in city parks and near lane trees. Often associated with elm and Horse chestnut. Flies around and sits on tree trunks near sunlit sap runs, usually at several metres above the ground. Often at fairly isolated and exposed trees, so not necessarily in forests. Visits flowering bushes and white umbellifers. Larva is easily found in sap runs of broad-leaved and coniferous trees.

Forest Sapeater Brachyopa grunewaldensis IDENTIFICATION 6–9 mm. Brachyopa with grey thorax and orange abdomen. Lower part of face only slightly protruding; vertex obliquely behind ocelli partly shiny, space between ocelli shiny also; inner side of third antennal segment without sensory pit or with rudimentary sensory pit only; arista bare. Thorax grey, hairs on notopleuron pale; proepimeron anteriorly with some long pale hairs; scutellum trapezoidal, anteriorly dark and with dense grey dusting; lower part of mediotergite shiny. Fore tarsus with tarsomeres bicoloured, basal part yellow, apical part dark-brownish. Abdomen red–brown; sternites 2–4 entirely dusted. Female: frons with shiny undusted longitudinal stripe, at level of front ocellus twice as wide as ocellus itself; tergite 2 entirely covered with pale hairs. SIMILAR SPECIES Most similar to B. insensilis; for differences, see that species. Like B. pilosa and B. scutellaris, but arista bare and third antennal segment without or with only rudimentary sensory pit. Like B. bicolor but sensory pit smaller and more indistinct, fore tarsus yellow and black, notopleuron entirely covered with pale hairs, transverse suture deeper, scutellum without transverse groove and vein M1 with shallower curve just before meeting crossvein dm-m. Like B. silviae and B. bimaculosa, but scutum without shiny black pair of markings at transverse suture. OCCURRENCE A growing number of observations in the south of Belgium since its discovery in 2017 may indicate ongoing spread over North-west Europe. Not known from Great Britain. ECOLOGY Both mixed and broad-leaved forests, mainly with oak. Visits flowers of Cow parsley, willow catkins and Blackthorn. Larva lives in tree holes and possibly also in sap runs.

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♂ pa i r o f sh i ny bl a ck sp o ts

a l m o st ba re

ante rior part of s cute llum gre y dus te d

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head

v e rte x duste d

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head

face

bl a ck m e di a n stri pe na rro w gro o v e w i de

ora n ge u sua l l y re achi n g h i nd ma rgi n

bl a ck ma rk i n sh a pe of p a wn chess p i ece

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head

face

♂

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gro o v e na rro w

orange not re aching hind margin m edi a n stri p e connects to b l a ck h i nd ma rgi n

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Broadleaf Twinspot Sapeater Brachyopa silviae IDENTIFICATION 6–9 mm. Brachyopa with conspicuous pair

of shiny black spots on scutum. Lower part of face moderately protruding; vertex dusted; at least centre of ocellar triangle without microtrichia, shiny black; inner side of third antennal segment without sensory pit or with rudimentary sensory pit only; arista bare. Thorax dusted grey, scutum at level of transverse suture with shiny triangular pair of black spots; proepimeron with some long pale hairs anteriorly; hairs on notopleuron pale; hair fringe under scutellum present; scutellum trapezoidal; lower quarter to half of mediotergite shiny. Abdomen red–brown; tergites 2–4 with pale hairs only; over half of sternites 3 and 4 shiny. Female: frons with shiny longitudinal stripe not reaching ocellar triangle. SIMILAR SPECIES Stands out in the field by distinct pair of shiny black spots on scutum. For other differences with B. bicolor, see that species. Very similar to B. insensilis and B. grunewaldensis, besides shiny spots on scutum, differs from former by hairs on anterior part of proepimeron and female

by differently shaped longitudinal stripe on frons, and from B. grunewaldensis by slightly more protruding face, entirely dusted vertex and more extensively dusted mediotergite. OCCURRENCE A very rare European endemic, with some populations just east of the range covered by this book. Not known from Great Britain. ECOLOGY Mixed and broad-leaved forests, often with beech and hornbeam. Visits hawthorn and other blossoming bushes. A male has been observed near a sap flux on hornbeam. Larval biology unknown. COMMENT From south-west Germany, Conifer Twinspot Sapeater Brachyopa bimaculosa is known. Very similar to B. silviae but face further protruding, ocellar triangle dusted, hair fringe under scutellum absent and sternites 3 and 4 to a large extent shiny.

Orange-belted Spineleg Myolepta dubia IDENTIFICATION 8–11 mm. A Myolepta with orange–red markings on abdomen. Face in male with, in female without, facial tubercle; third antennal segment orange. Wing: with indistinct dark spot in middle; vein M1 meets vein R4+5 only just before wing-tip at a sharp angle. All femora black, swollen and below with black spines; tibiae black; basal three tarsomeres of mid and hind tarsi (less often also fore tarsus) yellowish brown. Tergites 1 and 2 with extensive orange–red markings and wide black medial stripe, orange–red markings in male more extensive and usually reaching posterior margin of tergite 2. Male: face with narrow undusted black medial stripe from mouth edge up to facial tubercle. Female: central longitudinal groove on frons wide and reaching front ocellus; tergite 2 with black mark in shape of a pawn chess piece, which is at its widest close to posterior margin, before it slightly narrows again leaving the posterior margin of tergite 3 broadly yellow at the sides. SIMILAR SPECIES Superficially resembles Tropidia scita, but legs darker, third antennal segment paler, hind femur below without triangular tooth at tip and wing with dark spot. Much like M. potens; for differences, see that species.

OCCURRENCE Widespread but localised, seems to be increasing in Belgium. ECOLOGY Broad-leaved woodland, historical parkland and avenues with mature trees, especially with European beech; along forest edges and forest glades. Visits flowers such as white umbellifers and bramble, usually in partial shade. Females often found near tree cavities. Larva lives in water-filled tree cavities with decaying wood debris.

Small-spotted Spineleg Myolepta potens IDENTIFICATION 8–11 mm. A Myolepta with orange–red markings on abdomen. Face in male with, in female without, facial tubercle; third antennal segment orange. Tergites 1 and 2 with orange–red markings and wide black medial stripe, orange–red markings in male usually more extensive, reaching tergite 3 but not its posterior margin. Male: face with strongly widening, shiny black medial stripe from mouth edge to well over facial tubercle. Female: longitudinal central groove on frons narrow, ending just before front ocellus; tergite 2 with a black medial stripe connecting to (nearly) fully black posterior margin of tergite. SIMILAR SPECIES Much like M. dubia but male with strongly widening black medial stripe above facial tubercle and orange– red markings on tergite 3 not reaching posterior margin; female harder to identify, but black medial stripe on tergite 2 ending at posterior margin on a thin transverse black line, versus in M. dubia black medial stripe narrows at posterior margin which is largely yellow; groove on frons narrower and not reaching front ocellus; these characters do not always work, leaving some females best

unidentified. OCCURRENCE In the range covered by this book, only a small (meta)population in south-west Britain. This is the most northern population of its European range. ECOLOGY Broad-leaved forests and historical parkland with veteran trees and sufficient tree cavities; in Britain, Horse chestnut seems to be important. Visits umbellifers and sap runs of old trees. Larva lives in waterfilled tree cavities with decaying wood debris.

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♀ spo ts

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vei ns meet a t wi ngti p

fac e

a bdo m e n bl a ck

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wi n g

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head

a bdo m e n e nti re l y shi ny

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genitalia

surstyl us sho rt a nd bl unt

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sc u tu m

ti p o f a b d o me n a l m o st ba re

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Dark Spineleg Myolepta vara IDENTIFICATION 9–12 mm. A bee-mimicking brown Myolepta.

Face in male with, in female without, facial tubercle; third antennal segment red–brown. Sides of thorax shiny except proepimeron dusted and parts of anepisternum with faint dust; katepisternum with hairs. Wing: vein M1 meets vein R4+5 only just before wingtip, at a sharp angle; crossvein r-m located before middle of cell dm; wing with two dark spots, inner one most distinctive. Tip of mid and hind femora below with black spines. Abdomen black with golden-yellow to yellow-white hairs; tergite 1 and anterior half of tergite 2 grey-dusted. Male: face with strongly widening shiny medial stripe from mouth edge to well over facial tubercle. SIMILAR SPECIES An effective bee mimic, just like Brachypalpus and some Criorhina, but crossvein r-m located before middle of cell dm and vein M1 meets vein R4+5 only just before wing-tip. OCCURRENCE A rare and localised species, restricted to the southwest of the range covered by this book, but increasing in Belgium over the last decade and now locally present in good number. Not known from Great Britain. ECOLOGY Forest glades or along forest edges of large broad-leaved forests, mainly oak forests with old trees. Sits in sunlit spots on the forest floor or on low herbs. Visits flowers, including Cow parsley, but mainly bushes including hawthorn, Guelder-rose and Common dogwood. Larva lives in tree cavities with decaying organic matter. COMMENT Obscure Spineleg Myolepta obscura is a closely similar species of alluvial forest with observations just east of region covered by this book; like M. vara but hairs longer, third antennal segment black, frons with erect yellow hairs, sides of thorax dusted, and male with short narrow black longitudinal stripe on face.

Naked Wrinklehead Melanogaster nuda IDENTIFICATION 5–7 mm. Small black Melanogaster with sparse

hairs. Face without orbital strip; flagellum black. Wing: usually with dark spot in middle, although only distinct in female; apical part of vein M1 not recurrent; vein M1 perpendicular to vein R4+5. Male: mouth edge protruding further than facial tubercle; scutum with scattered long black hairs, mainly on anterior part; abdomen with dull area on tergites, margins shiny; tergite 8 with short hairs; genitalia with surstylus short, wide and with blunt tip. Female: scutum almost bare; abdomen entirely shiny, not dull in centre. SIMILAR SPECIES For differences with Chrysogaster, Orthonevra and Lejogaster, see account of M. hirtella overleaf. Female could be mistaken for a Cheilosia species owing to shiny abdomen, but orbital strip and facial tubercle absent and frons with transverse grooves. In Melanogaster, easy to recognise: male with hairs less dense on scutum, tergite 8 with shorter hairs and surstylus much shorter; female is the only Melanogaster with shiny abdomen and bare scutum, and with spot on wing, often missing in M. hirtella. OCCURRENCE Widespread and locally common on the continent but missing in Great Britain. ECOLOGY Wet open areas such as marshes and wet grasslands, generally on base-rich soil. Found low on vegetation, often on buttercup. Larva lives in water or mud near plant roots, in seepages or in the riparian zone of ponds and ditches.

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w i ng hya l i ne

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head

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a b d o me n

o nl y e dge s shi ny

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genitalia

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head

ti p o f a b d o me n ha i rs pa l e a nd e re ct

3 r d a nten na l segm ent bl a ck

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sc u tu m

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a b d o me n

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fa ci a l tu bercl e wel l devel o ped

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head

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g e n i ta l i a

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Common Wrinklehead Melanogaster hirtella IDENTIFICATION 6–8 mm. Small black and compact hoverfly. Face without orbital strip; flagellum black. Wing: apical part of vein M1 not recurrent; vein M1 perpendicular to vein R4+5. Posterior side of hind tibia with yellow hairs. Abdomen with dull area on tergites, margins shiny; tergite 1 and sternite 1 completely dull. Male: facial tubercle slightly less protruding than mouth edge; scutum with dense long erect hairs, hairs usually partly pale, at least in anterior half, although specimens with only black hairs occur rarely; tergite 8 with long hairs; genitalia with surstylus constricted near tip, appearing in side view as if there is a droplet hanging from tip. Female: frons with some transverse grooves; face without facial tubercle; mouth edge more or less angled compared to face; scutum with dense white–yellow almosterect hairs. SIMILAR SPECIES Could be mistaken for a Cheilosia but abdomen with dull centre and shiny margins, face without orbital strip, and in female frons with some transverse grooves and face without facial tubercle. Differs from Chrysogaster by black flagellum; from Orthonevra by not recurrent vein M1, dusted sides of tergite 1 and dusted sternite 1. Often confused with Lejogaster metallina, but males easily identified by having eyes meeting and flagellum smaller; female M. hirtella has black or sometimes slightly bronze instead of green shiny body, and abdomen centrally dull instead of shiny. Male differs from M. nuda by long hairs on tergite 8, denser hairs on scutum and larger, slenderer surstylus; female distinguished by scutum with much longer and denser hairs, wing without distinct spot in middle and abdomen with dull area on top. Much like M. aerosa, but hind tibia with more pale hairs; male usually with pale hairs on

scutum, facial tubercle less protruding and surstylus narrower at tip; female has erect instead of semi-adpressed hairs on scutum. Like M. parumplicata and M. curvistylus; for differences, see those species. OCCURRENCE Widespread and often abundant in moist grasslands. ECOLOGY In assorted wet open habitats such as fens, marshes, near ditches and wet unimproved grasslands but it will travel some distance from breeding habitat. Avoids more acidic peatlands. Adults are especially attracted to buttercup. Larva is aquatic amongst emergent vegetation.

Dark Wrinklehead Melanogaster aerosa IDENTIFICATION 7–8 mm. A fairly large, black Melanogaster. Face

without orbital strip; flagellum black. Wing: sometimes slightly dark in middle. Except near tip, posterior side of hind tibia with black hairs. Abdomen with dull area on top, margins entirely shiny. Male: facial tubercle well developed, protruding as far as or slightly further than mouth edge; scutum with dense, long and exclusively black hairs; tergite 8 with long hairs; genitalia with tip of surstylus bent inwards, pointing sideways. Female: transition from upper part of face to mouth edge angled; scutum and tergite 5 with short, semi-adpressed golden-yellow hairs. SIMILAR SPECIES For differences with Chrysogaster, Orthonevra and Lejogaster, see M. hirtella. Much like M. hirtella but posterior side of hind tibia with black hairs; males further distinguished by only black hairs on scutum, facial tubercle protruding further and surstylus less narrow, female distinguished by shorter and more adpressed hairs on scutum; sometimes, male M. hirtella can also have a completely black-haired scutum, so check additional characters before reporting a M. aerosa. Much like M. parumplicata; for differences, see that species. Male like M. curvistylus, but scutum with long black instead of very short predominantly pale hairs, hind tibia largely covered with black hairs instead of largely pale ones and genitalia different. OCCURRENCE A rare Melanogaster, that has declined over much of North-west Europe. ECOLOGY In Belgium and the Netherlands, the spring generation (April–June) is found in base-rich floodplain areas, around ditches and ponds whereas the summer generation (August–September) is found in base-poor bogs and moorland in heathland areas, indicating some ecological and possibly taxonomic differentiation. Most British records are from basepoor mire and boggy pools but a few are from coastal grazing

marshes. In spring, often to be found on buttercup and hawthorn; in summer, especially on Common heather. Flies low through the vegetation. Larva lives in shallow stagnant water or peaty pools near plant roots.

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head

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g e n i ta l i a

sho rt se m i -a dpre sse d ha i rs

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g ra d ua l b end

head

♂

be ndi ng a t v e ry ti p a nd na rro w i ng i n a sm a l l to o th

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fac e

♂

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v e ry sho rt, pre do m i na ntl y pa l e ha i rs

scutum

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Chalk Wrinklehead Melanogaster parumplicata IDENTIFICATION 7–9 mm. A fairly large, black Melanogaster. Face

without orbital strip; flagellum black. Posterior side of hind tibia predominantly covered with black hairs. Abdomen with dull area on tergites, margins shiny. Male: facial tubercle weakly developed, protruding less or barely as far as mouth edge; scutum with black hairs; tergite 8 with long hairs; genitalia: tip of surstylus much less bent, more or less pointing forward. Female: transition from upper part of face to mouth edge gradual, not angled; scutum and tergite 5 with short erect to slightly semi-adpressed yellow hairs. SIMILAR SPECIES For differences with Chrysogaster, Orthonevra and Lejogaster, see M. hirtella. Much like M. hirtella but hind tibia more extensively covered with black hairs; scutum of male with black hairs and surstylus less slender at tip; female hard to identify, but supposedly, besides darker hairs on hind tibia, hairs on scutum on average slightly shorter and more adpressed. Male differs from M. aerosa by less developed facial tubercle and in genitalia, surstylus wider and sides parallel for more of their length, strongly tapering near tip, versus in M. aerosa more gradually tapering over whole length; female differs by slightly longer, greyer and more erect hairs on scutum and by less angled transition from face to mouth edge, but difference is subtle and certain identification not always possible. For differences with M. curvistylus, see that species. OCCURRENCE Very localised in the south of the region covered by this book. Not known from Great Britain but records from Warwickshire in prime M. parumplicata habitat require further investigation. ECOLOGY Mainly wet calcareous forest with seepages, grasslands with seepages, on calcareous soil. Larval biology unknown.

Hidden Wrinklehead Melanogaster curvistylus IDENTIFICATION 7 mm. A rare species of which the female is

still unknown. Male: face narrow, without orbital strip; flagellum black. Scutum with short erect pale hairs, sometimes hairs dark in centre; scutum shiny. Wing: transparent; apical part of vein M1 not recurrent; vein M1 perpendicular to vein R4+5. Hind tibia largely with yellow hairs. Abdomen with dull area on tergites, margins shiny; tergite 1 and sternite 1 entirely dull; tergite 8 with long hairs; genitalia with surstylus seen from side relatively wide and parallel sided for most of its length, bending at very tip and narrowing in a small tooth. Female: unknown. SIMILAR SPECIES For differences with Chrysogaster, Orthonevra and Lejogaster, see M. hirtella. Female unknown, so following text applies to males only. Males can always be identified by shape of surstylus: when seen from side, wide and parallel sided for most of its length whereas in M. hirtella it gradually tapers towards tip before bending and narrowing into a tooth. However, one very helpful character can also be assessed in the field: the scutum is covered with very short, predominantly pale hairs; in other Melanogaster species, hairs are much longer and, except in M. hirtella, black. Moreover, scutum is mainly shiny, while at least the centre it is dull in other Melanogaster species. Face should be narrower compared to other Melanogaster, but not always obvious. OCCURRENCE Very rare, described only in 1998 from Germany and Serbia, subsequently also found in Austria and Poland. Not known from Great Britain. ECOLOGY All finds are from wet meadows and floodplain forest near streams or small rivers, but little is known about its exact requirements. Larva undescribed.

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f ace

face

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abdomen

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face

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head

face

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f a ce w i de

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a l m o st ba re

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f a ci a l tube rcl e w e l l de v e l o pe d

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♂

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f ac e

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face

f a ce v e ry w i de

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d i sti n ctl y ha i re d

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Dark-winged Wrinklehead Chrysogaster solstitialis IDENTIFICATION 6–8 mm. A distinctive Chrysogaster with red eyes, purple sheen on scutum and dark wings. Face without orbital strip; third antennal segment predominantly orange. Proepimeron shiny. Wing: dark, brown to brown–black; wing base not distinctly yellow; apical part of vein M1 not recurrent, vein M1 perpendicular to vein R4+5. Abdomen with dull area on tergites, margins shiny; tergite 1 and sternite 1 entirely dull. Male: face at level of antennae about as wide as an eye; eyes meeting at a right or sharp angle; scutum dull in middle, contrasting with shiny posterior margin and scutellum; scutellum seemingly bare due to very short hairs, much shorter than hairs on scutum, only posterior margin of scutellum distinctly with hairs. Female: face at level of antennae narrower than an eye. SIMILAR SPECIES Like Cheilosia but abdomen with dull centre and shiny margins, face without orbital strip and in female frons with some transverse grooves. Differs from Melanogaster species by orange third antennal segment. Differs from Orthonevra species by vein M1

not recurrent, dusted sides of tergite 1 and dusted sternite 1. Differs from Lejogaster metallina by purple instead of green sheen on scutum, orange third antennal segment and male with eyes meeting. Like C. cemiteriorum and C. basalis, but wing base not yellow, proepimeron shiny and in the male face less inflated, therefore facial tubercle more distinct. Like C. virescens and C. rondanii, but face narrower, with purple instead of green sheen on scutum, male with much shorter hairs on scutellum and scutum dull in centre. OCCURRENCE Widespread in Northwest Europe, a common Chrysogaster except in treeless areas. ECOLOGY In or near damp forests, often in nearby tall-herb vegetation with umbellifers. Mainly found on white umbellifers such as hogweed and angelica. Also active in the shade or even during light rains. Larva lives in shallow water or mud with much organic matter such as leaves and twigs.

Green Wrinklehead Chrysogaster virescens IDENTIFICATION 7–8 mm. A bronze to green shiny Chrysogaster.

Third antennal segment largely orange. Scutum weakly shiny bronze-green in male, distinct shiny green in female; proepimeron shiny. Wing: slightly dark, without yellow base. Abdomen with dull area on tergites, abdominal margins shiny. Male: facial tubercle relatively distinct; eyes meeting at an angle of c. 100°; face at level of antennae about twice as wide as an eye; frons shiny; frons not densely punctate; scutum with brown–black hairs, slightly adpressed; scutellum with hairs, hairs about as long as scutum. Female: frons bare; face at level of antennae about 1.1–1.3 times wider than an eye; scutum almost bare or with only minute hairs; sternite 1 with short hairs, hairs shorter than width of hind femur. SIMILAR SPECIES For differences with Melanogaster and Orthonevra, see C. solstitialis. Like Riponnensia splendens but smaller, less elongated and without white longitudinal stripes on scutum. Both sexes differ from C. solstitialis by less dark wings and wider face; male by shiny centre of scutum, scutellum with much longer hairs; female by green instead of purple sheen on scutum. Very similar to C. rondanii but face less wide, proepimeron shiny;

male facial tubercle better developed and frons shinier and more finely punctate; female with bare or almost bare scutum and frons and sternite 1 with shorter hairs. OCCURRENCE Widespread and locally common in flower-rich places in moorlands. ECOLOGY Both in neutral seepages in broad-leaved forest and valley bogs and in acid Sphagnum bogs. Sits on leaves of bushes or trees and visits white umbellifers and blossoms. Females fly low above Sphagnum beds. Larval biology unknown.

Broad-faced Wrinklehead Chrysogaster rondanii IDENTIFICATION 7–8 mm. A bronzy Chrysogaster. Third antennal

segment predominantly orange–red. Scutum shiny bronze–green; proepimeron weakly dusted. Wing: slightly dark, without yellow base. Abdomen with dull area on tergites, abdominal margins shiny. Male: facial tubercle wide and indistinct; eyes meeting at an obtuse angle, clearly more than 100°; face very wide, face at level of antennae over twice as wide as an eye; scutum with brown–black hairs, slightly adpressed; scutellum with distinct hairs, about as long as on scutum. Female: frons with distinct short white hairs; frons lightly dusted and densely punctate; face at level of antennae about 1.3–1.5 times wider than an eye; scutum with short but distinct semi-adpressed white hairs; sternite 1 with long hairs, length equal to width of hind femur. SIMILAR SPECIES For differences with Melanogaster and Orthonevra, see C. solstitialis. Could be mistaken for C. solstitialis but face much wider; for more differences see C. virescens. Very similar to C. virescens, but face even wider (although there is some overlap), proepimeron slightly dusted and male with less distinct facial tubercle, eyes

meeting at a larger angle and frons slightly dusted and more coarsely punctate; female with longer and more distinct hairs on scutum, frons and sternite 1. Compared to C. virescens, has a slightly more bronze instead of green sheen, but difference subtle. OCCURRENCE A localised species in the south of range covered by this book. An early species, flies a few weeks before the very similar C. virescens. Not known from Great Britain. ECOLOGY Forest glades in broad-leaved forest with seepages, springs or brooks on neutral to base-rich soil. Visits flowering trees and bushes, mainly Blackthorn and willow but also broom, hawthorn, Rowan and Bird cherry. Larval biology unknown.

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face

face

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th o ra x l a te ra l

pro e pi m e ro n duste d

3 rd antennal segment

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o ra nge

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f ace

face

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th o ra x l a te ra l

pro e pi m e ro n shi ny

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face

two longitudi na l dus t stri pes tra nsv e rse gro o v e s

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Yellow-winged Wrinklehead Chrysogaster cemiteriorum IDENTIFICATION 6–8 mm. A shiny black species with distinctive

yellow wing base. Third antennal segment reddish below. Proepimeron densely dusted. Wing: base yellow; wing usually with dark spot in middle. Abdomen with dull area on tergites, abdominal margins shiny. Male: face wide, at level of antennae almost 1.5 times wider than an eye; face swollen, facial tubercle weakly developed; length of hairs on posterior margin of scutellum about a third of length of scutellum itself; lower part mediotergite shiny; scutum dusted anteriorly. Female: face wide, at height of antennae distinctly wider than an eye. SIMILAR SPECIES For differences with Melanogaster and Orthonevra, see C. solstitialis. Yellow wing base is a helpful first clue in the field. Differs from other Chrysogaster species by combination of yellow wing base, shiny black appearance and densely dusted proepimeron. Can be confused with C. solstitialis if yellow wing base is less distinctive but besides dusted proepimeron, wing is less dark and face wider. C. basalis has

wing base yellow as well, but that species has face narrower, proepimeron shiny, is usually a bit smaller, male with posterior margin of scutellum with shorter hairs and scutum shinier, and especially female with blue instead of black sheen. Distinguished from all Cheilosia, including C. impressa, by absence of orbital strip. OCCURRENCE Widespread and frequent in Great Britain, but rather local over most of North-west Europe. Has declined over the last decades. ECOLOGY Wetlands, valley bogs, wet meadows, near rivulets and springs along woodland margins, on base-rich soil. May move to nearby drier ground to feed. Regularly visits white umbellifers. Active both in full sun and partial shade. Larval biology unknown.

Blue Wrinklehead Chrysogaster basalis IDENTIFICATION 5–7 mm. Dark blue to black, shiny species,

blue sheen especially distinct in female. Third antennal segment reddish below. Proepimeron shiny. Wing: with yellow base and dark spot in middle. Abdomen with dull area on tergites, abdominal margins shiny. Male: face at level of antennae about as wide as an eye; length of hairs on posterior margin of scutellum exceeding no more than a quarter of length of scutellum itself; entire scutum shiny. Female: face at level of antennae about as wide as an eye. SIMILAR SPECIES For differences with Melanogaster and Orthonevra, see C. solstitialis. Shares yellow wing base with C. cemiteriorum but proepimeron shiny; moreover, usually a little smaller, face narrower, posterior margin of scutellum in male with shorter hairs and scutum shinier, and especially in female with blue, instead of black, sheen. OCCURRENCE A south European species, with some strays in the southern range covered by this book. Not known from Great Britain. ECOLOGY Along springs and streams and on flower-rich meadows in and near broad-leaved forest. Visits white umbellifers. Larval biology unknown. COMMENT A second species

C. coerulea morphologically close to C. basalis was recently promoted to species level on the basis of material from Spain, but it may occur further north as well. It is not yet clear which species occurs in the area covered by this book. C. coerulea has a more distinctive blue shine and males have a distinct facial tubercle and some differences in the genitalia.

Stripe-backed Glimmer Riponnensia splendens IDENTIFICATION 8–9 mm. An elongated, shiny green hoverfly. Face without facial tubercle; mouth edge slightly (male) to distinctly (female) protruding; face between antenna attachment and mouth edge grey-dusted; third antennal segment orange below; eyes in living specimens brown–green. Scutum with short hairs; anterior half of scutum with two longitudinal dust stripes. Wing: apical part of vein M1 not recurrent, vein M1 perpendicular to vein R4+5. Abdomen with dull area on tergites, margins shiny. Sternite 1 shiny. Legs entirely dark, with green sheen. Male: eyes meeting. SIMILAR SPECIES Similar to Melanogaster, Chrysogaster, Lejogaster and Orthonevra, but more elongated, scutum with dusted longitudinal stripes and face with wide grey dust band. Moreover, Orthonevra has vein M1 different, Chrysogaster and Melanogaster have sternite 1 dusted and Lejogaster has entire abdomen shiny and males have eyes widely separated. OCCURRENCE Widespread and frequent in Great Britain, but localised and rare over much of the continental range covered by this book. ECOLOGY Springs and seepages in broad-leaved forests,

near streams and ditches in grasslands, on base-rich soil. Flies low in partial shade and rests on leaves. Mainly visits umbellifers. Larva lives in stagnant water with decaying organic matter.

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eyes wi del y sep a ra te d

♂

e ntire ly s hiny gre e n

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head

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head

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protarsus

3 r d a nte nna l se gm e nt bl a ck

bl a ck

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head

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wi ng ba se ye l l o w

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o ra n ge

protarsus

3 r d a nte nna l se gm e nt o ra nge be l o w

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head

tra nsv e rse gro o v e s stri pe v e ry cha ra cte ri sti c

♂ ce ll r 4 + 5 re ctangular

ho ri zo nta l stri pe

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abdomen

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Green Shimmer Lejogaster metallina IDENTIFICATION 6–8 mm. Metallic green hoverfly. Face without

facial tubercle; mouth edge protruding; third antennal segment black, although sometimes a little brownish red below in female. Scutum and abdomen entirely shiny green with very short, mainly white hairs; anterior anepisternum bare. Wing: apical part of vein M1 not recurrent, vein M1 perpendicular to vein R4+5; wing base yellow. Legs including tarsi entirely shiny green–black. Male: eyes widely separated; third antennal segment strikingly large, distinctly wider than long. SIMILAR SPECIES Males (check tip of abdomen for genitalia) easily recognised as Lejogaster by widely separated eyes; moreover, third antennal segment wider than long and very large. Female like Chrysogaster but third antennal segment black or brownish, abdomen entirely shiny and sternite 1 shiny; like Orthonevra species but vein M1 not recurrent; like Melanogaster species but with green instead of black sheen and abdomen also shiny on top; be aware, top of abdomen of L. metallina is often glossy blue with green shiny

edges and this contrast can be misinterpreted as a dull area on top of abdomen. Like L. tarsata but differs by having black tarsi, usually black third antennal segment and bare anterior anepisternum, in L. tarsata anterior anepisternum with hairs in upper posterior corner. L. tarsata usually is a more colourful and slightly smaller species than L. metallina (female with stronger blue, male with stronger green and copper). OCCURRENCE A widespread and common species in North-west European marshes. ECOLOGY Various wet habitats: marshes, banks of ditches and pools, wet grasslands, often on peaty ground and not in acid conditions. Flies low and often visits buttercup. Larva lives in wet environments with decaying organic matter.

Splendid Shimmer Lejogaster tarsata IDENTIFICATION 5–7 mm. Handsome shiny golden-green hoverfly. Face without facial tubercle; mouth edge protruding; third antennal segment orange below, sometimes only at very base. Anterior anepisternum with hairs in upper posterior corner. Wing: apical part of vein M1 not recurrent, vein M1 perpendicular to vein R4+5; wing base yellow. Legs dark but middle segments of fore tarsus, and also often to a lesser extent of mid tarsus, orange. Entire abdomen shiny. Male: eyes widely separated; third antennal segment strikingly large. Female: top of abdomen shiny blue, sides with green, red and golden sheen. SIMILAR SPECIES Male easily recognised as Lejogaster: eyes widely separated, face without facial tubercle and third antennal segment very large. Female recognised as Lejogaster by combination of golden shiny green appearance, apical part of vein M1 not recurrent and entire abdomen shiny; similar to Chrysogaster virescens and C. basalis, but third antennal segment never entirely orange, abdomen shiny blue on top, wing base yellow and middle segments of fore and mid tarsi orange. Typical specimens readily distinguished from L. metallina by orange middle segments of fore and mid tarsi

and third antennal segment orange below; sometimes these characters are less distinct, but always recognisable by hairs on upper posterior corner of anterior anepisternum, bare in L. metallina. OCCURRENCE Mainly a coastal species in North-west Europe. ECOLOGY Marshes, coastal wetlands, often on peat, to some extent indicative of base-rich environments either with salts or chalk. Found at the edge of marshes on flowers of plants such as Yellow flag, buttercups or white umbellifers. Larva lives in decaying organic matter in the riparian zone or in water-filled hoof indentations in waterlogged peaty soil.

Stripe-eyed Mucksucker Orthonevra elegans IDENTIFICATION 5–6 mm. Enigmatic Orthonevra with purple

stripe on eye. Face without facial tubercle; mouth edge hardly protruding; third antennal segment very long, about four times longer than wide. Wing: apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. Legs partly orange: extreme tip, basal part of tibiae and basal tarsomeres orange. Shiny green species, abdomen with dull area on top, but entire margins shiny. SIMILAR SPECIES Instantly recognisable by purple stripe over eyes; in collected specimens this character can fade slightly over time, but still identifiable by long third antennal segment: four times longer than wide, shorter in all similar species. OCCURRENCE Used to be very rare but widespread in Central and Eastern Europe, but has gone extinct over most of its range. A few populations remain in northern Denmark. Not known from Great Britain. ECOLOGY Transition mire, where base-rich and base-poor water meet in marshes, in flushes in meadows or along pond margins. Larval biology unknown. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 3 1 3

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head

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head

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le gs black

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abdomen

3 r d a nte nna l se gm e nt sl i ghtl y l o nge r tha n w i de

♂

head

♂

3 r d a nte nna l se gm e nt 2 × l o nge r tha n w i de

♀

ti p a b d o me n

tube rcl e

l eg s a l l bl a ck

♀

fo re le g

abdomen

tube rcl e

♂

V -sha pe d i nci si o n

♂

head

kn ees p a l e 3 r d a nte nna l se gm e nt 2 × l o nge r tha n w i de

f ore leg kne e s pa l e

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a b d o me n

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Atlantic Mucksucker Orthonevra brevicornis IDENTIFICATION 5–7 mm. Face without facial tubercle; third antennal segment hardly longer than wide, extensively orange below. Wing: pterostigma pale yellow to pale brown; apical part of vein M1 perpendicular or slightly recurrent to vein R4+5. Legs entirely shiny black–green. Body blackish with green and bronze sheen; abdomen dull on top with shiny edges; sternite 1 and sides of tergite 1 shiny. Male: eyes meeting over a distance equal to length of ocellar triangle. Female: posterior margin of tergites 4 and 5 smooth without tubercle or incision. SIMILAR SPECIES Quite a dark and dull Orthonevra, so could be mistaken for a Chrysogaster or Melanogaster, but shape of vein M1 different, sternite 1 shiny, male with face concave, without facial tubercle, and female has combination of partly orange third antennal segment and quite dense and long, erect pale hairs on scutum. Owing to black legs may be confused with O. nobilis, but third antennal segment shorter and rounder, pterostigma slightly paler, male has eyes meeting over a longer distance and female

tergites 4 and 5 of normal shape. OCCURRENCE Widespread but generally scarce. ECOLOGY Wet broad-leaved forests, alder carr, near seepages or ponds. Visits flowers on forest edge, often willow, Blackthorn and umbellifers. Larva inhabits wet decaying material near seepages and pools. COMMENT Two species very similar to O. brevicornis were recently found in North-west Europe. O. arcana is present in Belgium while an as-yet undescribed species very similar to O. brevicornis was found in the Netherlands and is common further east. This eastern taxon is the true O. brevicornis and our western species will get a new name. All three species differ subtly in external characters and we advise routinely collecting some males and checking male genitalia for a positive identification. Male O. arcana may be easily recognised by the slender surstyli, while the new species similar to O. brevicornis has a differently shaped aedeagus and pale scutum hairs.

Slim-horned Mucksucker Orthonevra nobilis IDENTIFICATION 4–6 mm. A small Orthonevra with black legs.

Face without facial tubercle; third antennal segment about twice as long as wide, with pointed tip, orange below. Wing with weak dark patch in middle and some yellow at base; pterostigma dark brown; apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. Legs entirely dark, shiny green. Abdomen dull on top with shiny edges; sternite 1 and sides of tergite 1 shiny. Male: eyes meeting over a very short distance. Female: posterior margin of tergite 4 with a tubercle in middle; posterior margin of tergite 5 with a small V-shaped incision in middle. SIMILAR SPECIES Best identified from Melanogaster, Chrysogaster and Lejogaster by typical Orthonevra wing venation: vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. In Orthonevra, shares entirely dark legs only with O. brevicornis but third antennal segment longer, males with eyes meeting over shorter distance and female with tubercle on posterior margin of tergite 4 and incision on posterior margin of tergite 5. OCCURRENCE Widespread but in low numbers. The only Orthonevra with two broods a year

treated in this book, commonly seen in summer. ECOLOGY Mainly near ponds, seepages or streams but also often in dry flower-rich meadows near forests. Visits umbellifers such as Cow parsley, Wild carrot and hogweed. Larva lives in organic matter at the edge of streams and pools.

Nordic Mucksucker Orthonevra erythrogona IDENTIFICATION 5–6 mm. A small Orthonevra with shiny

metallic-green body. Face without facial tubercle; third antennal segment about twice as long as wide. Wing: apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. Legs entirely dark except knees: only extreme tip of femora and base of tibiae orange; sometimes also base of tarsomere 1 pale. Abdomen dull on top with shiny edges; sternite 1 and sides of tergite 1 shiny. SIMILAR SPECIES Differs from other Orthonevra by black legs with orange knees; other species have legs either entirely black or orange parts more extensive. O. geniculata sometimes also has knees orange, but orange at base of tibiae much more extensive and third antennal segment longer. OCCURRENCE A very rare Orthonevra in the range covered by this book, restricted to its northern edge. Not known from Great Britain. ECOLOGY Marshes, banks of pools, fens. Larva has been found in mud with lots of organic matter.

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face

tra nsv e rse gro o v e s

p tero sti gm a ye l l o w w i th d a rk bro w n spo t a t ba se

cros s ve in r-m infus cate d da rk brown

f a ce w i de

♂

3 r d a nte nna l se gm e nt 3 × l o nge r tha n w i de

head

fo re leg

exten si vel y ora n ge

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abdome n

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face

g e n i ta l i a

tra n sve rse groo v e s

co nv e x

f a ce na rro w ba re

♂ surstyl us wi th i n ci si o n

fo re leg

head

3 × l o nge r tha n w i de

su rstyl us wi d e

♂

geni ta l i a

♀ ♂

g e n i ta l i a

a ngl e d

ha i re d

3 × l o nge r tha n w i de

surstyl us na rro w

♂

head

fo re leg a ed ea gus wi th l o ng p roj ecti on

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Willow Mucksucker Orthonevra geniculata IDENTIFICATION 5–6 mm. Small shiny black–green to green

Orthonevra. Face without facial tubercle; third antennal segment about 2.5–3 times as long as wide; face below antennae about as wide as an eye. Wing: apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance; crossvein r-m infuscated dark brown; pterostigma yellow with dark-brown spot at base. Legs partly pale, basal tarsomeres orange and base of tibiae extensively orange. Abdomen dull on top with shiny edges; sternite 1 shiny. SIMILAR SPECIES Identified as an Orthonevra species by typical wing venation: vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. In Orthonevra, readily identified by combination of partly pale legs, dark-brown crossvein r-m and bicoloured pterostigma. Dark-brown crossvein r-m sometimes indistinct, rendering it like O. intermedia but that species has face narrower, pterostigma without dark base, has a more blue–green sheen and flies

later in the season. OCCURRENCE An early Orthonevra of boggy environments. ECOLOGY Valley mire, carr, bogs and fens, usually on peat and where wet willow or birch woodland is present. Often sits on reed stems or on branches of willows. Males fly quickly through flowering bushes and regularly sit lengthwise on twigs looking for females. Visits flowers, including those of willow, Blackthorn and umbellifers. Larval biology unknown, but probably lives in peaty mud.

Mire Mucksucker Orthonevra intermedia IDENTIFICATION 6–7 mm. Fairly large Orthonevra with partly pale

legs and shiny green body. Face without facial tubercle; narrow, below antennae clearly less wide than an eye; third antennal segment about three times longer than wide. Wing: apical part of vein M1 perpendicular or slightly recurrent to vein R4+5, giving cell r4+5 a rectangular appearance. At least base of tibiae extensively orange, basal tarsomeres orange. Abdomen dull on top with brightly shiny edges. For description of genitalia, see at O. stackelbergi. SIMILAR SPECIES The typical shape of vein M1 is the bast way to distinguish it from Melanogaster, Chrysogaster and Lejogaster. Legs more extensively yellow compared to O. erythrogona. Like O. geniculata, but slightly larger, lacks infuscated crossvein r-m, lacks bicoloured pterostigma and has narrower face. Very similar to O. stackelbergi; for differences, see that species. OCCURRENCE A north European species that does not occur south of Belgium. Locally common in the Netherlands, otherwise very rare. ECOLOGY A typical species of quagmire, valley mires, lowland fen and transition fen with Marsh cinquefoil, often in the succession to forest. Often to be found on flowers of

Alder buckthorn, Yellow flag or Marsh spurge. Males fly very low and fast with erratic flights over waterlogged Sphagnum beds of quaking bogs, and regularly sit, presumably waiting for females to arrive. Larval biology unknown.

Stackelberg’s Mucksucker Orthonevra stackelbergi IDENTIFICATION 6–7 mm. Extremely similar to O. intermedia; the characters described there also apply to this species. For a description of the genitalia, see below. SIMILAR SPECIES For differences with species other than O. intermedia, see that species. Certain separation from O. intermedia is possible only after checking genitalia, so it is necessary to collect the specimen, dissect the genitalia and study it under the microscope. Genitalia of freshly collected females can be removed by flattening abdomen with tweezers and then pushing it a bit backwards, which is significantly more difficult with relaxed specimens from collections. Male: aedeagus with long projection, short in O. intermedia; surstylus narrow and without incision, wide and with an incision halfway in O. intermedia. Female: side margins of sternite 8 angled, anterior part quite straight and widening towards posterior part, tapering again at posterior part, while in O. intermedia side margins not angled but convex; sternite 8 with hairs in middle, while bare in O. intermedia. OCCURRENCE Scandinavia, Poland and the Baltic states, but

isolated (relic) populations in eastern Denmark and Belgium. A rare species over its whole range. Not known from Great Britain. ECOLOGY Flushes in forest, marshes, near temporary streams. Favouring forest more than open marshes compared to O. intermedia. Rests on leaves of bushes, up to 3 metres above the ground, and quickly flies back and forth. Visits flowers, in Belgium collected on Common tormentil and Guelder-rose. Larval biology unknown.

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ste rn i te 1

a b d o me n

♂ outer two ta rsom eres bl a ck ste rni te 1 a bse nt

rounde d a ngl e

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genitalia

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mo rp h flavescens

ste rn i te 1

abdo me n

ste rni te 1 pre se nt, w i de r tha n l o ng

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head

po stpro no tum bl a ck

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genitalia

m o uth e dge bl a ck

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a b d o me n

po stp rono tu m yel lo w

surstyl us sho rt a nd w i de

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Variable Pufftail Sphegina sibirica IDENTIFICATION 7–8 mm. A large and slender Sphegina.

Face without facial tubercle and entirely black; mouth edge protruding; frons with short white hairs. Scutum with short white adpressed hairs; katepisternum shiny, dusted only along belly suture between fore and mid coxa. Wing: vein M1 with rounded angle. Hind femur strongly swollen; fore and mid legs entirely yellow except outer two tarsomeres black. Abdomen constricted; sternite 1 absent or reduced to narrow strip, instead there is a whitish membrane, compare with illustration of S. clunipes where sternite 1 is present; abdomen largely black, but partly or almost entirely yellow specimens occur, colour morph flavescens. Male: eyes widely separated; genitalia with surstylus short, tapered and slightly curved. SIMILAR SPECIES A large Sphegina, could be mistaken for Baccha elongata, but that species is even slenderer, has hind femur not strongly swollen and males have eyes meeting. Like S. montana, both differ from other Sphegina in having katepisternum shiny and fore and mid tarsi with outer

two tarsomeres black, strongly contrasting with three yellow basal tarsomeres; S. sibirica differs from S. montana and all other Sphegina by reduced sternite 1. OCCURRENCE This slender fly has achieved a remarkable colonisation of North-west Europe including crossing the North Sea to Great Britain in less than 20 years. Now common in suitable habitat over the whole range. ECOLOGY Damp mixed and coniferous forest, mainly spruce plantations, but wanders widely. Visits flowers of umbellifers and flowering bushes. Males patrol constantly over and through the flowers. Larva seems to develop primarily in sappy decay under the bark of fallen trunks or branches of conifers such as spruces in damp, shady places.

Common Pufftail Sphegina clunipes IDENTIFICATION 6–7 mm. A typical Sphegina with constricted

abdomen and strongly swollen hind femur. Face without facial tubercle; lower half of face white–yellow, although usually mouth edge largely black; mouth edge protruding; third antennal segment not very large. Scutum and postpronotum black; katepisternum dusted. Wing: vein M1 with rounded angle. Fore and mid tarsi entirely yellow; hind coxa yellow. Abdomen either with pale transverse band on tergite 3 or entirely black; sternite 1 well developed, shiny. Male: surstylus long and slender with a row of hairs on inner side. SIMILAR SPECIES Larger than Neoascia and with rounded instead of sharp-angled vein M1. Compared to N. sibirica has sternite 1 well developed and uniformly coloured fore and mid tarsi. Shares white–yellow lower part of face with S. elegans, but distinguished by postpronotum black, third antennal segment smaller and mouth edge usually black, and male with longer and slenderer surstylus. OCCURRENCE The commonest and most widespread of the Sphegina in the range covered by this book. ECOLOGY Damp forests, both broad-leaved and coniferous forests, often near streams or ditches but also in

the wider environment. Flies low through vegetation in the shade and visits umbellifers such as Fool’s-watercress. Larva lives in waterlogged dead wood, or under rotting bark and sap runs of broad-leaved (and possibly coniferous) trees.

Elegant Pufftail Sphegina elegans IDENTIFICATION 6–7 mm. A Sphegina with a large third antennal segment. Face without facial tubercle; lower half of face white– yellow, usually including mouth edge; third antennal segment large. Postpronotum pale, contrasting with otherwise black scutum; katepisternum dusted. Wing: vein M1 with rounded angle. Fore and mid tarsi entirely yellow; hind coxa yellow; hind femur strongly swollen. Abdomen constricted; either with pale transverse band on tergite 3 or entirely black; sternite 1 well developed, shiny. Male: surstylus short and wide. SIMILAR SPECIES Larger than Neoascia and with rounded instead of sharp-angled vein M1. Compared to N. sibirica has sternite 1 well developed and fore and mid tarsi entirely yellow. Shares white–yellow lower part of face with S. clunipes, but distinguished by postpronotum pale, third antennal segment larger, mouth edge usually white–yellow and surstylus of male short and wide. OCCURRENCE Widespread but scarcer than S. clunipes, more confined to small streams in forests. ECOLOGY Wet broad-leaved forest with flushes and streams, almost always close to running water. Usually flies in

partially shaded spots near streams. Visits mainly white umbellifers such as Fool’s-watercress. Larva has been found in sap runs of elm and among twigs and organic matter in the bed of a small stream.

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head

cos ta and s ubcos ta join at the le ve l of cros s ve in r- m

f a ce bl a ck

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wingtip hyaline

hind coxa

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cos ta and s ubcos ta join be fore cros s ve in r- m

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ye l l o w -bro w n

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a b d o me n

head

terg i te 2 l o ng

f a ce bl a ck

surstyl us e l o nga te d w i th po i nte d ti p

wingtip s lightly infus cate d

hind coxa

♂

ye l l o w -bro w n

♂

♀

g e n i ta l i a

♂

a b d o me n

head

f ro ns w i th l o ng ha i rs

terg i te 2 sho rt a nd wi de

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robus t s pe cie s

hind coxa

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Lesser Pufftail Sphegina verecunda IDENTIFICATION 5–7 mm. Fairly short-bodied Sphegina with a dark face. Face without facial tubercle and entirely black; frons with short golden-yellow hairs; antennae brown–black, but third antennal segment sometimes orange–brown. Katepisternum dusted. Wing: vein M1 with rounded angle; costa and subcosta join at level of crossvein r-m. Hind femur strongly swollen; fore and mid tarsi yellow, sometimes upper side of apical two tarsomeres slightly dark; hind coxa yellow–brown. Abdomen constricted; sternite 1 well developed, shiny. Male genitalia: surstylus rather wide and with blunt tip. Female: tergite 2 longer than width of its posterior margin. SIMILAR SPECIES Shares black face with S. sibirica, S. spheginea, S. montana and S. nigra; for differences with first three, see S. nigra. Very similar to S. nigra but antennae usually slightly darker, wing-tip transparent and costa and subcosta join at level of crossvein r-m instead of before crossvein r-m; first two characters not too reliable, last character not always obvious, so some females probably best

left unidentified; males easily identified by genitalia: surstylus wide and with blunt tip instead of narrow with pointed tip. OCCURRENCE Widespread, but a localised species that may be linked to old forest relics. ECOLOGY Old humid broad-leaved forest, often with beech, usually but not always with running water. Often found at white umbellifers in partial shade. Larva lives in decaying sap under the bark of fallen logs or in sap runs of broad-leaved trees.

Red-horned Pufftail Sphegina nigra IDENTIFICATION 6–8 mm. A Sphegina with black face and orange third antennal segment. Face without facial tubercle and entirely black; third antennal segment dark orange; frons with short golden-yellow hairs. Scutum with white adpressed hairs; katepisternum dusted. Wing: vein M1 with rounded angle; costa and subcosta join before crossvein r-m; wing-tip usually slightly dark. Fore and mid tarsi entirely yellow; hind coxa yellow–brown; hind femur strongly swollen. Abdomen constricted; sternite 1 well developed, shiny. Male: surstylus elongated and with pointed tip. Female: tergite 2 longer than width of its posterior margin. SIMILAR SPECIES Shares entirely black face with S. sibirica, S. spheginea, S. montana and S. verecunda. Like S. sibirica but sternite 1 present, fore and mid tarsi with less contrasting tarsomeres and katepisternum dusted. Like S. spheginea but slenderer, hind coxa yellow–brown, frons with shorter hairs, shape of vein M1 different and in female tergite 2 longer. Like S. montana but katepisternum dusted and scutum with white hairs. Most similar to S. verecunda; for differences, see that species. OCCURRENCE Restricted to the south-east of the range

covered by this book and generally much more localised and much scarcer than the other Sphegina. Not known from Great Britain. ECOLOGY Broad-leaved forest with flushes, brooks or streams on base-rich soils. Larval biology unknown. COMMENT This species is also known as Sphegina clavata.

Stocky Pufftail Sphegina spheginea IDENTIFICATION 5–8 mm. A robust black Sphegina. Face without facial tubercle, entirely black; face below antennae not concave; antennae black. Scutum with black hairs; katepisternum dusted. Wing: vein M1 bends early compared to similar species, therefore ending on vein R4+5 at a slightly sharp angle; costa and subcosta join at level of crossvein r-m. Hind coxa brown–black or black; tarsi black. Abdomen relatively short and wide, black; sternite 1 well developed, shiny. Male: frons with long erect black hairs, some hairs longer than width of third antennal segment; surstylus elongated, curved, with slightly wider base. Female: frons with long hairs, at least with a few long erect black hairs near ocellar triangle; tergite 2 short, shorter than width of its posterior margin; anterior margin of tergite 2 wide. SIMILAR SPECIES A dumpy Sphegina, stands out amongst other species. Owing to entirely black face can be confused with S. sibirica, S. montana, S. nigra and S. verecunda. Like S. sibirica, but more compact, sternite 1 present, fore and mid tarsi entirely black and katepisternum dusted. Like S. nigra and S. verecunda, but hind

coxa darker, frons with longer hairs, scutum with black hairs and in female tergite 2 shorter. Like S. montana but katepisternum dusted, face below antennae not concave and surstylus of male with less wide base. OCCURRENCE A rare northern and boreomontane species in Europe. In the region covered by this book restricted to one area in Central Germany. Not known from Great Britain. ECOLOGY Broad-leaved and coniferous forests, near brooks. Larval biology unknown.

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head

f a ce co nca v e

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th o ra x l a te ra l abdomen k a te pi ste rnum shi ny

♂

genitalia

♂

♂

head

3 r d a nte nna l se gm e nt sho rt

brown infus cate d tergi te 4 wi th yel l o w sp o ts

♀

a b d o me n

♂

♂

head

ta rsom eres 4 a nd 5 bl a ck

3 r d a nte nna l se gm e nt sho rt

ti p h i nd femu r yel l o w

wing hyaline

b l a ck ri ng fo re t ib ia

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p l a te s b e h i n d h i n d c o xa

j ust to uchi ng

abdomen

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Shiny Pufftail Sphegina montana IDENTIFICATION 5–8 mm. A dark Sphegina with shiny katepisternum. Face without facial tubercle, usually entirely black, but sometimes with a little yellow; face below antennae concave; antennae black. Katepisternum entirely shiny, except with very narrow dusted strip at belly suture. Wing: sometimes somewhat dark. Tarsi partly dark; male has femora and tibiae of fore and mid legs mostly black or brown, but in female usually yellow; trochanter of hind leg dark. Sternite 1 well developed, shiny. Male: frons with long erect black hairs; scutum with black hairs; abdomen black or with small brown spots; surstylus with very wide base abruptly turning into narrow tip. Female: abdomen black, usually with red–brown spots; hind tibia with pale base and tip but without pale ring in the middle. SIMILAR SPECIES Combination of a shiny katepisternum (with some practice, visible in the field) and sternite 1 present diagnostic. Male stands out, just like S. spheginea, by extensively dark legs, long black hairs on frons and black hairs on scutum,

but compared to S. spheginea less compact, face concave and surstylus very different. Females unlike S. elegans, S. clunipes, S. nigra and S. verecunda, being without pale ring on hind tibia just below middle. OCCURRENCE A very local species of low mountain ranges in Central Europe, very rare at the east of region covered by this book. Mainly flies May–June. Not known from Great Britain. ECOLOGY Broad-leaved and coniferous forests, in the vicinity of streams. Visits flowers of composites and umbellifers in the shade. Larval biology unknown.

Many-spotted Fen Fly Neoascia interrupta IDENTIFICATION 5–6 mm. A relatively large Neoascia with

infuscated crossveins. Face without facial tubercle; mouth edge distinctly protruding; third antennal segment short, slightly longer than wide, at most 1.5 times longer than wide in female. Plates behind hind coxae not meeting, widely separated by a membrane. Wing: crossvein dm-m and apical part of vein M1 infuscated. Tergites 2–4 with pairs of yellow spots, tergite 2 sometimes black, spots on tergite 3 sometimes fused to a band. Male: tergite 8 with black hairs. SIMILAR SPECIES The only Neoascia species with yellow markings on tergite 4. Of four Neoascia with infuscated veins, only species with third antennal segment short, at most 1.5 times longer than wide, at least twice as long as wide in the others. Infuscated veins can be indistinct, but yellow markings on tergite 4 distinguishes it from species with transparent wings. OCCURRENCE A relatively recently discovered species in Britain but now widespread in southern and central areas. Widespread in lowland areas on the continent and locally common. ECOLOGY Swamps, rather nutrient-rich lakes and pools with a well-developed fringe of emergent vegetation (usually where

bulrush is present), coastal lagoons and grazing marsh ditches; not in acid bogs and mires. Flies above water along reed and bulrush vegetation and visits flowers such as those of buttercup. Larva described but biology unknown.

Short-horned Fen Fly Neoascia geniculata IDENTIFICATION 4–6 mm. A small dark Neoascia with contrasting

tarsi. Face without facial tubercle; mouth edge distinctly protruding; third antennal segment short, not much longer than wide. Plates behind hind coxae just meeting or just separated. Wing: transparent. Fore tibia with black ring; fore tarsus with tarsomeres 1, 4 and 5 black, tarsomeres 2 and 3 yellow; extreme tip of hind femur bright yellow. Abdomen of female usually entirely black, male has yellow band on tergite 3 which narrows towards side margin. Male: tergite 8 with pale hairs. Female: tergite 2 evenly widening from base to posterior margin. SIMILAR SPECIES Like N. annexa and N. tenur, but these species have tip of hind femur black, third antennal segment longer, fore tarsus with outer two tarsomeres yellow and plates behind hind coxa meeting over a longer distance. Like N. meticulosa but that species has fore tibia with indistinct brown ring at most, outer two tarsomeres of fore tarsus yellow, third antennal segment longer and plates behind hind coxa widely separated. OCCURRENCE A widespread but rather scarce species, easily overlooked between

other Neoascia. ECOLOGY Different types of wetland habitats, but most abundant along ponds and ditches in the alluvial or coastal plain (especially where Reed sweet-grass is abundant), sometimes also valley mires and base-poor fen. Flies low through vegetation and visits flowers of, for example, water-plantain, buttercup and Cuckooflower. Larva likely lives at the edge of ponds and ditches.

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♂

♂

head

3 r d a nte nna l se gm e nt a t l e a st 1 . 5 × l o nge r tha n w i de wing hyaline

m o uth e dge pro trudi ng ti p h i nd femu r bl a ck p l a te s b e h i n d h i n d c o xa

co nstri cted b etween tergi tes 1 a nd 2

black ring

w i de l y to uchi ng

fo re leg

♀

abdomen

♂

♂

head

3 r d a nte nna l se gm e nt a t l e a st 1 . 5 × l o nge r tha n w i de

m o uth e dge l e ss pro trudi ng ti p h i nd femu r bl a ck

wing hyaline

p l a te s b e h i n d h i n d c o xa

w i de l y to uchi ng

co nstri cted h a l fwa y terg i te 2

♀

abdomen

♂

♂

head

3 r d a nte nna l se gm e nt 2 × l o nge r tha n w i de ti p h i nd femu r yel l o w

wing hyaline

p l a te s b e h i n d h i n d c o xa

ti b i a yel l o w fo re leg

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♀

w i de l y se pa ra te d

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Black-kneed Fen Fly Neoascia tenur IDENTIFICATION 3–5 mm. A very small Neoascia, one of the

smallest hoverflies of the region. Third antennal segment about 1.5 times longer than wide. Plates behind hind coxae meeting widely. Wing: transparent. Tip of hind femur black, at most a little orange–yellow; fore tibia almost always with black ring; fore tarsus with tarsomere 1 blackish, remaining tarsomeres yellow. Male usually with yellow bands on tergites 2 and 3, in female usually reduced to spots or abdomen even entirely black; yellow markings on tergites 2 and 3 narrow towards side margin, at most posterior margins of yellow markings on tergite 3 reach side margin. Male: tergite 8 with pale hairs. Female: abdomen constricted between tergites 1 and 2. SIMILAR SPECIES Like N. meticulosa, N. geniculata and N. annexa with transparent wings; for differences with N. meticulosa, see that species; compared to N. geniculata hind femur usually without brightyellow tip, third antennal segment longer, outer two tarsomeres of fore tarsus not black, plates behind hind coxa meeting over a

longer distance and female more often with yellow markings on abdomen; much like N. annexa but smaller; for more differences, see that species. OCCURRENCE Widespread, frequent and often (very) abundant. ECOLOGY Wide range of wet habitats such as marshes, along banks of lakes, streams and ditches, valley mire, at the edge of raised bog. Flies low through and sits in dense vegetation near water. Visits low flowers as bedstraw, Marsh marigold or buttercup. Larva develops among submerged dead plant material.

Broad-banded Fen Fly Neoascia annexa IDENTIFICATION 6–7 mm. The largest Neoascia treated in this

book. Face without facial tubercle; face only slightly protruding; third antennal segment at least 1.5 times longer than wide. Plates behind hind coxae meeting over considerable length. Wing: transparent. Tip of hind femur black; fore tarsus with tarsomere 1 sometimes blackish, remaining tarsomeres yellow. Abdomen with bands on tergites 2 and 3 that reach the side margin at full width. Male: tergite 8 with black hairs. Female: abdomen constricted halfway, at tergite 2. SIMILAR SPECIES Mouth edge less protruding than in any other Neoascia. Other differences: much like N. tenur but larger, yellow markings on tergites 2 and 3 reaching side margin at full width, in male tergite 8 with black hairs and in female tergite 2 constricted halfway; like N. meticulosa but that species has plates behind hind coxae widely separated, male has tergite 2 black and female has abdomen entirely black. Like N. geniculata but third antennal segment longer, tip of hind femur black, outer two tarsomeres of fore tarsus yellow, plates behind hind coxa meeting over a longer distance and female with yellow markings on abdomen. Could be mistaken for Sphegina species

due to relatively large size but vein M1 and crossvein dm-m bent at a sharp angle. OCCURRENCE A very localised and scarce species in the range covered by this book, mainly in upland areas. Not known from Great Britain. ECOLOGY Usually along brooks and rivers in broad-leaved forests. Flies low along the river edge, often sits on leaves of herbs and visits low flowers close to the river. Larva lives in organic matter along the edge of brooks.

Yellow-kneed Fen Fly Neoascia meticulosa IDENTIFICATION 4–6 mm. Small dark Neoascia. Face without

facial tubercle; mouth edge moderately protruding; third antennal segment 1.5–2 times as long as wide. Plates behind hind coxae not meeting, widely separated by a membrane. Wing: transparent. Tip of hind femur bright yellow; fore tibia yellow, at most with indistinct brown ring; fore tarsus yellow except basal tarsomere. Abdomen of female entirely black, in male with a yellow band on tergite 3 reaching side margin over its full width. Male: tergite 8 with black hairs. Female: abdomen distinctly wide and club-shaped; abdomen constricted halfway, at tergite 2. SIMILAR SPECIES Has wing transparent like N. tenur, N. annexa and N. geniculata. Like N. tenur but fore tibia yellow, plates behind hind coxae widely separated, third antennal segment longer, male with tergite 2 black and tergite 3 with yellow band reaching side margin over its full width, and female with abdomen always black and abdomen constricted halfway at tergite 2. Like N. geniculata but plates behind hind coxae widely separated, third antennal segment longer, outer two tarsomeres of fore leg pale, fore

tibia mainly yellow and male has black hairs on tergite 8. Like N. annexa but plates behind hind coxa widely separated, mouth edge more protruding, male with tergite 2 black and abdomen of female entirely black. OCCURRENCE A widespread and often common Neoascia, together with N. tenur. ECOLOGY A variety of lush swamp conditions, lowland fen, valley mire and pond margins usually in neutral to base-rich wetlands, but also seepages at the edge of raised bog. Flies low through vegetation and visits flowers such as buttercup and Marsh marigold. Larva lives in submerged decaying organic matter.

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♂

abdo me n

ti p o f a b d o me n

♂

bl a ck -ha i re d h i nd ma rgi n ro ughl y stra i g ht

cros s ve ins infus cate d

3 r d a n ten na l segm ent 2 × l o nger th a n wi d e

fo re fem ur indis tinct brow n ri ng

♂

p l a te s b e h i n d h i n d c o xa e

j ust to uchi ng

head

♂

head

♂ 3 r d a nte nna l se gm e nt 2 × l o nge r tha n w i de

cros s ve ins infus cate d yel l ow

♀

fo re femur

♂

h i nd ma rgi n l i ke a n i n verted V

abdomen

ti p o f a b d o me n

bl a ck -ha i re d

♂

head

♂

3 r d a nte nna l se gm e nt 2 × l o nge r tha n w i de

cros s ve ins infus cate d

♂

ti p o f a b d o me n

terg i te 2 bl a ck fo re fem ur black ri ng

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abdomen

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Smudge-veined Fen Fly Neoascia podagrica IDENTIFICATION 5–6 mm. A relatively large Neoascia. Third

antennal segment about twice as long as wide. Plates behind hind coxa just meeting. Wing: crossvein dm-m and apical part of vein M1 infuscated. Fore femur and fore tibia yellow or with indistinct brown ring. Male: tergites 2 and 3 with yellow bands, posterior margin of yellow band on tergite 2 is more or less straight; tergite 8 with black hairs. Female: tergites 2 and 3 with yellow bands, on tergite 2 often interrupted and instead a pair of spots, or markings even absent; posterior margin of marking on tergite 2 straight or slightly oblique. SIMILAR SPECIES Shares infuscated veins with N. interrupta, N. obliqua and N. unifasciata but plates behind hind coxa just meeting instead of being widely separated; for more differences with N. interrupta and N. obliqua, see those species; differs from N. unifasciata by presence of yellow markings on tergite 2, hind femur without black ring; female distinguished by more constricted tergite 2 and male by black hairs on tergite 8. If infuscated veins are indistinct

(often in fresh individuals), like N. tenur but third antennal segment longer and fore femur and fore tibia lack distinct black ring. OCCURRENCE Widespread and common also outside natural habitats, only absent in very dry or acid environments. ECOLOGY Found in many different habitats, including wet grasslands, marshes and ditch sides but also parks and gardens. The only Neoascia that regularly occurs away from wetlands. Flies low through vegetation and visits low and mainly small flowers including those of Common tormentil, buttercups, spurges, umbellifers and Yarrow. Larva lives in organic matter in moist circumstances such as ditch sides but also cow dung or trampled wet mud.

Butterbur Fen Fly Neoascia obliqua IDENTIFICATION 5–6 mm. Medium-sized Neoascia with infuscated

veins. Face without facial tubercle; face distinctly protruding; third antennal segment at least twice as long as wide. Plates behind hind coxae not meeting, widely separated by a membrane. Wing: crossvein dm-m and apical part of vein M1 infuscated. Fore femur and fore tibia yellow or with indistinct brown ring. Yellow marking on tergite 2 resembling an inverted V, but can also be interrupted or even absent. Male: tergite 8 with black hairs. Female: basal one-third of length of tergite 2 with sides roughly parallel, whereafter widening. SIMILAR SPECIES Similar to N. interrupta, N. podagrica and N. unifasciata owing to infuscated veins. Easily distinguished from N. interrupta by black tergite 4 and longer third antennal segment. Like N. podagrica, the inverted V on tergite 2 is a helpful first clue, although this rarely also occurs in female N. podagrica, so check for the widely separated plates behind hind coxae; furthermore, abdomen shorter and at tip more convex. Like N. unifasciata if markings on tergite 2 are absent, but fore femur without distinct black ring, male has tergite 8 with black hairs and female has sides of tergite 2 parallel at base.

OCCURRENCE Strongly associated with Butterbur stands and can be very common there but generally very localised, reflecting the distribution of the plant. ECOLOGY Roadsides, along streams and rivers, wherever larger Butterbur stands are present. Flies low through or rests on vegetation. Males fly amongst or sit on the leaves of Butterbur. Larva probably lives in the leaves or stems of Butterbur.

Single-banded Fen Fly Neoascia unifasciata IDENTIFICATION 5–6 mm. A relatively large Neoascia with infuscated veins. Face without facial tubercle; face distinctly protruding; third antennal segment about twice as long as wide. Plates behind hind coxae not meeting, widely separated by a membrane. Wing: crossvein dm-m and apical part of vein M1 infuscated. Fore femur yellow with wide black ring. Tergites 2 and 4 black but tergite 3 with a yellow band, in female constricted or interrupted in middle. Male: tergite 8 with pale hairs. Female: tergite 2 evenly widening from base to posterior margin. SIMILAR SPECIES Shares infuscated veins with N. interrupta, N. podagrica and N. obliqua; lacks yellow markings on tergite 4 of N. interrupta and has third antennal segment longer; unlike N. podagrica, tergite 2 black, plates behind hind coxae widely separated, fore femur with distinct black ring and male has pale hairs on tergite 8; unlike N. obliqua tergite 2 black (which rarely also occurs in that species), fore femur extensively black, male tergite 8 with pale hairs and female has tergite 2 evenly widening over full length. OCCURRENCE A very rare Neoascia that is easily

overlooked among the much commoner and nearly always cooccurring N. obliqua. It is so far unclear why N. unifasciata can be abundant in one place but is absent from other similar-looking places. Not known from Great Britain. ECOLOGY Along brooks and streams with Butterbur in meadows near or in forest. Often flies with N. obliqua in the vicinity of Butterbur. Larval biology unknown.

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♀

cel l r 1 cl o se d

ti bi a bl a ck

♀

tw o v e rti ca l ba nds o f ha i rs head

♂

♀

ptero stigm a sho rter

ba se ye l l o w

f ore tarsus

en ti rel y pa l e

♂

♀

wi n g pte ro sti gm a pa l e a nd l o ng

pte ros tigma pale and long

ba se ye l l o w

f ore tarsus

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Common Drone Fly Eristalis tenax IDENTIFICATION 14–16 mm. A large robust honeybee mimic; one of our most familiar hoverflies. Face with very wide black medial stripe; arista with short hairs; eyes with two vertical bands of hairs, that are not obvious at every angle and therefore not visible in every photo (see also photo 1 in the introduction). Abdomen black or with orange–red spots, extent of orange variable especially in male, sometimes tergites 2 and 3 predominantly orange, female often only has spots on sides of tergite 2 or is black. Fore tarsus black; hind femur black. Wing: vein R4+5 sinuous; cell r1 closed. SIMILAR SPECIES Eyes with two vertical bands of hairs distinguishes it from all other Eristalis. Owing to large size, can be mistaken for E. pertinax and E. similis when bands of hairs on eyes are missed or not visible on photos; differs from both by short hairs on arista and black hind tibia, hind tibia with yellow base in other two; furthermore, differs from E. similis by shorter pterostigma and from E. pertinax by dark fore tarsus. Differs from all other bee-mimicking hoverflies that

are not Eristalis by combination of sinuous vein R4+5 and closed cell r1. OCCURRENCE Most widespread hoverfly species in the world, summer populations can be significantly boosted by mass migration. ECOLOGY Found almost everywhere, from forests to grasslands to city gardens, but especially abundant in open areas. Males hover near forest edge and on hill-tops and both sexes visit many flowers including those of yellow composites, umbellifers and ivy. Females hibernate and appear on mild winter days. Larva occurs in wet conditions with abundant organic matter, including ditch sides, wet silage or cattle dung.

Tapered Drone Fly Eristalis pertinax IDENTIFICATION 11–17 mm. A large Eristalis with yellow feet.

Face with very thin black medial stripe; arista with long hairs; eyes with an even cover of brownish hairs. Wing: sometimes infuscated in middle; pterostigma elongated and dark brown; vein R4+5 sinuous; cell r1 closed. Fore and mid tarsi yellow. Abdomen conical, especially in male; tergite 2 with orange, triangular pair of spots; spring specimens have fairly long hairs and less conspicuous spots on abdomen. SIMILAR SPECIES Owing to large size, mainly confused with E. tenax and E. similis, but easily distinguished from them and any other Eristalis by yellow fore and mid tarsi, in other Eristalis tarsi either entirely black or at least outer tarsomeres black; differs from E. similis also by shorter and darker pterostigma (but variable, with some overlap) and from E. tenax by yellow base of hind femur, long hairs on arista and eyes without vertical stripes of hairs. OCCURRENCE The commonest Eristalis in spring, especially near forest and wetlands. ECOLOGY All kinds of habitats, broadleaved forests, gardens, grasslands, etc. Less frequent in large open agricultural land (as opposed to E. tenax). Flies around bushes, often settles on the ground near water and visits flowers of many

plants, trees and bushes. The only Eristalis preferring partial shade on hot sunny days. Males frequently hover along forest edges or in forest glades in spring but less so in summer. Larva occurs in water with decaying organic matter including manure.

Glass-winged Drone Fly Eristalis similis IDENTIFICATION 13–16 mm. A large Eristalis. Face with very

thin black medial stripe; arista with long hairs; eyes with even brownish hairs. Wing: pterostigma pale brown and long, 4–6 times longer than wide; wing sometimes with indistinct brown spot, but usually transparent; vein R4+5 sinuous; cell r1 closed. Fore tarsus mainly or entirely black; base of hind tibia yellow. Abdomen not conical. SIMILAR SPECIES On average, pterostigma longer compared to other Eristalis, but some females of E. pertinax can have equally long pterostigma, so use other characters too. Owing to large size, mainly confused with E. pertinax and E. tenax. Like E. tenax, but base of hind tibia largely yellow, arista with long hairs and eyes without vertical stripes of hairs. Easily overlooked in the field among much commoner E. pertinax, but fore tarsus black, while entirely yellow in E. pertinax. OCCURRENCE On the continent (Belgium, the Netherlands), this species has recently evolved from a regular migrant to a well-established and abundant (locally commonest) Eristalis. In Great Britain, still an irregular migrant so far. The

number of migrants varies widely among years. ECOLOGY Near wetlands and forests, parks, gardens, but also in more open habitats with hedges, thickets. Males hover several metres above the ground, often along forest tracks. Frequently visits flowers including those of lime and white umbellifers. Larval biology unknown but possibly comparable to E. pertinax. COMMENT For some time known under its junior synonym E. pratorum.

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a n te n n a

♂

w i th l o ng ha i rs

e ye s to uch o v e r a co nsi de ra bl e di sta nce

ti p b l a ck

mid tibia

♂

head

a n te n n a

♂

w i th sho rt ha i rs

♂

head

e ye s na rro w l y se pa ra te d

ti p yel l ow

mid tibia

♀

♂

a b d o me n

pte ro sti gm a v e ry sho rt

wing hyaline

♀

♂

head

f o re f e mu r

yel l o w-h a i red

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Eurasian Drone Fly Eristalis arbustorum IDENTIFICATION 9–11 mm. A small Eristalis. Face covered entirely

with white hairs, without bare black medial stripe, although very worn individuals can have a narrow black stripe; arista with long hairs, although old specimens can lack many. Wing: transparent; pterostigma 2–4 times longer than wide; vein R4+5 sinuous. One-quarter or one-third of mid tibia tip black. Male: eyes meeting over a considerable distance; large pair of spots on tergite 2 continues on tergite 3. SIMILAR SPECIES With E. abusiva instantly recognisable by absence of black medial stripe on face, although black stripe sometimes indistinct in E. similis, but that species much larger and has longer pterostigma. In worn individuals, a narrow black stripe can occur, and they resemble E. nemorum of similar size, but stripe on face still narrower and more irregular, pterostigma longer and male with more extensive pale markings on tergite 3. Most similar to E. abusiva, but arista with much longer hairs, mid tibia distinctly black at tip and in male eyes meeting over a considerable distance. OCCURRENCE A very

common Eristalis in open habitats. ECOLOGY Various open and half-open habitats, including agricultural areas, parks, gardens and flowery meadows, from the coastal plain to mountain tops. Visits flowers, such as those of Yarrow, mayweed, yellow composites and umbellifers. Larva lives in organically enriched wet conditions, woodland rides and clearings, from the riparian zone of ponds to cow dung.

Levels Drone Fly Eristalis abusiva IDENTIFICATION 8–11 mm. A small Eristalis. Face covered entirely

with white hairs or with very narrow black medial stripe around facial tubercle; arista with short hairs. Wing: transparent or with indistinct brown tint; pterostigma 2–4 times longer than wide; vein R4+5 sinuous. Mid tibia completely yellow, at most tip a little brown–yellow. Male: eyes narrowly separated or just meeting. Female: scutum rather dull with pale stripes and spots. SIMILAR SPECIES Similar to E. arbustorum owing to white face or only a very small black medial stripe, but easily distinguished from it, even with a hand lens: hairs on arista much shorter (be careful with worn individuals), mid tibia at end yellow or with indistinct brown smudge, not black all around, and eyes of male narrowly separated instead of meeting over a considerable distance. All these characters also work to distinguish it from E. nemorum; furthermore, face without black medial stripe, pterostigma longer and male with more extensive yellow markings on tergite 3. OCCURRENCE Has largely disappeared from inland locations over the past decades in Belgium and the Netherlands, and has become mainly coastal. In Great Britain, not rare in coastal

districts with grazing marsh but can occur well inland, especially along floodplains, even at high altitude. ECOLOGY Freshwater to mildly brackish coastal grazing marshes, preferably on peat. Visits flowers, including thistles, Sea aster and mayweed. Larva lives in the riparian zone of ditches, pools and in waterlogged, trampled mud of coastal marshes.

Stripe-faced Drone Fly Eristalis nemorum IDENTIFICATION 10–13 mm. A small to medium-sized Eristalis.

Face with narrow black medial stripe, remainder of face yellow below dusting; arista with long hairs. Wing: transparent in male, in female usually dark brown along veins; pterostigma short, not much longer than wide; vein R4+5 sinuous. Hind tarsus black; upper side of tarsomeres 4 and 5 of all legs with yellow hairs; posterior part of fore femur with yellow hairs. Abdomen: tergite 2 in male with distinct side spots, spots smaller or absent in female; tergite 3 in the male in upper corners sometimes with small yellow spots, black in the female; tergites with white posterior margin. SIMILAR SPECIES Can be confused with several other Eristalis but pterostigma not much longer than wide, versus longer in all other Eristalis. For additional differences with E. arbustorum, E. abusiva and E. horticola, see those species. Like E. picea and E. rupium but, amongst other characters, wing without central dark spot. Male much like that of E. pseudorupium but pterostigma shorter (subtle difference), ground colour of face yellow instead of black, medial stripe on face narrower, posterior part of fore femur with

yellow instead of black hairs and two apical tarsomeres with yellow hairs on upper side; female lacks dark medial spot on wing. OCCURRENCE Not often in very large numbers, as are some other common Eristalis, but a widespread and common species. ECOLOGY A wide variety of open and half-open habitats including gardens and parks. Frequently visits flowers of many sorts but seen especially frequently on ragworts, thistles and umbellifers. Males circulate fast and noisily along forest edges and flowers, attacking similar-sized flies. The only Eristalis in which male, as a courtship behaviour, hovers for a long time just above a female, sometimes with several males at the same time, in a stacked arrangement. Larva lives in streams and pools, but also in cow dung. COMMENT For some time, known under the names E. interruptus or E. interrupta.

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♀

a b d o me n

te rgi te 2 dul l

dark sp o t

te rgi te s 3 a nd 4 ye l l o w -ha i re d

♂

♀

fac e

f ace

♀

a b d o me n

h i n d ta rsu s

fa ce yel l o w e nti re l y bl a ck

bl a ck med i a n stri p e

♀

♂

a b d o me n

te rgi te 2 pa rtl y shi ny dark s pot

f a ce stro ngl y pro trudi ng do w nwa rds

♂

fo re femur

black b ri stl e-l i ke h a i rs

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fa ce strongl y protrudi ng d o wnwa rd s

♂

head

head

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Stripe-winged Drone Fly Eristalis horticola IDENTIFICATION 11–14 mm. A medium-sized, brightly marked

Eristalis with a dark stripe on wing. Face with black medial stripe; face below dusting yellow; face not protruding; arista with long hairs. Wing: pterostigma twice as long as wide; wing with dark brown to black band in middle, sometimes indistinct; vein R4+5 sinuous. Base of hind femur yellow; posterior part of fore femur with yellow hairs, in male tip also with a few black hairs; hind tarsus always black. Tergite 2 with pair of large orange–yellow spots; tergite 2 entirely dull, best assessed by viewing at an oblique angle and comparing dull tergite 2 with partly shiny tergites 3 and 4; tergites 3 and 4 almost entirely covered with yellow hairs. SIMILAR SPECIES Differs from all similar species except E. jugorum by dull tergite 2, in other species at least orange spots at sides shiny. Like E. jugorum but base of hind femur yellow, face not protruding, black medial stripe on face narrower and male has posterior part of fore femur with yellow hairs instead of black bristly hairs. Can be confused with E. nemorum but that species has shorter pterostigma, yellow spots on tergite 2 shiny, black hair bands on tergites 3 and 4 and wing different, in male wing transparent, in female veins often brown infuscated but not with dark spot in middle. Shares dark spot on wing with the trio E. picea, E. rupium and E. pseudorupium, but these species have ground colour of face black (except females E. pseudorupium and E. picea), tergites 3 and 4 extensively covered with black hairs, at least yellow side spots on tergite 2 shiny, hind tarsus often partly yellow, in male posterior part of fore femur with black hairs and females usually with smaller and less-bright orange side spots on tergite 2. E. horticola appears brighter than the above-mentioned

trio due to yellow face and brighter orange spots on abdomen. OCCURRENCE Widespread and relatively common; sensitive to droughts. ECOLOGY Various wetland habitats near forests, parks or gardens, but most common in older peaty marshes, valley mires and wet heath. Visits wide array of flowers. Larva lives in organically enriched water; egg-laying has been observed in a moist ditch and in cattle- or horse-trampled peat of mire and boggy pools.

Snouted Drone Fly Eristalis jugorum IDENTIFICATION 11–15 mm. Medium-sized Eristalis with snout-

like face. Face with very wide black medial stripe, face itself black but at sides below dusting partly yellow; face strongly protruding downwards; arista with long hairs. Wing: with dark-brown to black band across in middle, distinct in female, sometimes indistinct in male; pterostigma short, at most twice as long as wide; vein R4+5 sinuous. Hind femur black, only tip pale; hind tarsus completely black on all sides. Tergite 2 largely dull, but with hardly visible shiny spots at side margin; tergites with white posterior margin. Male: posterior part of fore femur densely covered in black bristlelike hairs. Female: scutum with ginger-coloured hairs; posterior part of fore femur with yellow hairs; tergite 2 with pair of large orange–yellow spots; abdomen entirely covered with white– yellow hairs. SIMILAR SPECIES The only Eristalis with a snout-like face, although to a lesser extent this can also be present in other species. Most resembling E. horticola but, besides elongated face, base of hind femur black, black medial stripe over face wider and in male posterior part of fore femur with dense black bristle-like hairs. Especially in male, dark spot on wing can be indistinct, thus can be confused with E. nemorum, but tergite 2 duller, face with wider black medial stripe and pterostigma slightly longer. Like trio E. picea, E. rupium and E. pseudorupium, but they often have hind tarsus partly pale, males have hairs on posterior part of fore femur not bristly, often (not always) ground colour of face black and females have tergite 3 more extensively covered with black hairs. OCCURRENCE A species of small river valleys in Central European mountains, restricted to the east of region covered by this book, but has strongly decreased over the past decades. Not known from Great Britain. ECOLOGY Flower-rich meadows along valley mires. Along streams, forest tracks. Often visits knapweeds,

Devil’s-bit scabious, Field scabious, and white umbellifers. Larval biology unknown.

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a b d o me n

spo ts a nd bl a ck i n be tw e e n shi ny

dark s pot

e re ct bl a ck ha i rs

pointe d tip

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a b d o me n

h i n d ta rsu s

l o bes strongl y curved

usua l l y pa l e

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p aramere lat era l

paramere f ront view

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face

f a ce be l o w dusti ng bl a ck wing hyaline bl a ck m e di a n stri pe

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a b d o me n

a dpre sse d bl a ck ha i rs

tip wide ning

pa l e l o bes stro ngl y cu rved

bl a ck -ha i re d

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p aram ere lat eral

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h i n d ta rsu s

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Spring Drone Fly Eristalis picea IDENTIFICATION 10–14 mm. Dark medium-sized Eristalis with distinct brown–black band on wing. Face with wide black medial stripe, remainder of face below grey dusting variable, black or dark yellow; face wide; arista with long hairs. Scutum dull; hairs on scutum yellow or orange–yellow; scutellum with yellow hairs, at most with a few black hairs. Wing: with central dark band that can be large and squarish in female; pterostigma 1.5–2 times as long as wide; vein R4+5 sinuous. Base of hind femur yellow; tarsomere 1 of hind leg variable, yellow to black–brown. Tergite 2 with pair of spots, both spots and area between spots shiny, remainder of tergite 2 dull; tergite 3 with long erect hairs; sternites 2 and 3 dull, contrasting with shinier sternite 4. Male: posterior part of fore femur largely covered with black hairs; posterior half of tergites 3 and 4 with black hairs; genitalia: lobes on aedeagus strongly curved, paramere in side view with pointed tip. Female: tergites 3 and 4 largely covered with black hairs and shiny except dull posterior margin. SIMILAR SPECIES Shares dark band on wing with E. horticola, but that species has tergite 2 entirely dull, ground colour of face more yellow, tergites 3 and 4 entirely or mostly with yellow hairs, female anterior and posterior margins of tergites 3 and 4 dull, hind tarsus always black and male has yellow hairs on posterior part of fore femur. Very similar to both E. rupium and E. pseudorupium; for differences with E. rupium, see that species. Unlike E. pseudorupium has scutellum with yellow hairs, scutum dull, face wider, with black shiny strip between spots on tergite 2, male with dark band in wing and tip of paramere pointed and female tergite 3 with erect hairs only. E. alpina usually also has a dark spot in the wing, but in

that species the male has hairs on posterior part of fore femur yellow and hind femur thickened, and the female has a slightly thickened hind femur, a more densely dusted scutum, hair on the body more white–grey and face narrower. OCCURRENCE A widespread and locally common species in North-west Europe, but absent from Great Britain. ECOLOGY Fenland, moorland, valley mire and marshes in the alluvial plain but rather mobile and can appear some distance from these habitats. Often visits blossoming trees, such as willow, Blackthorn and hawthorn. Larval biology unknown, but likely aquatic.

Carr Drone Fly Eristalis pseudorupium IDENTIFICATION 10–13 mm. A medium-sized Eristalis. Face with

wide black medial stripe, remainder of face below dusting usually black in male, in female usually dark yellow; face narrow; arista with long hairs. Scutum shiny and with orange–yellow hairs; scutellum with black band of hairs. Wing: transparent in male, in female with dark band in centre; pterostigma 1.5–2 times as long as wide; vein R4+5 sinuous. Base of hind tibia yellow, more extensively so in female; basal tarsomere in female yellow, in male yellow or dark, but usually not black. Pair of orange spots on tergite 2 shiny, space between spots dull; tergites 3 and 4 largely with black hairs; sternites 2 and 3 dull, contrasting with shiny sternite 4. Male: posterior part of fore femur largely with black hairs; genitalia: lobes on aedeagus strongly curved, paramere in side view club-shaped. Female: tergite 3 on posterior part with short semi-erect hairs; tergites 3 and 4 shiny with dull anterior and posterior margins. SIMILAR SPECIES Male resembles E. nemorum given transparent wing and similar genitalia, but posterior part fore femur largely covered with black hairs, face with more extensive black ground colour and wider black medial stripe, pterostigma slightly longer, basal tarsomere of hind tarsus often yellow or yellowish and outermost two tarsomeres of all tarsi with black hairs on upper part. Amongst other characters, tergites 3 and 4 with largely black hairs distinguish it from E. horticola and E. jugorum. For differences with E. alpina, see that species. Compared to E. rupium and E. picea, with shinier scutum, male with transparent wing and much wider paramere, female with short, semi-adpressed hairs on posterior part of tergite 3; compared with E. picea, face narrower, lacking shiny area between orange spots on tergite 2 and scutellum with band of black hairs; for additional differences with E. rupium,

see that species. OCCURRENCE A northern species in Europe that occurs as far south as Belgium, has recently expanded strongly in Belgium. At least during its current expansion phase, has been capable of long-distance dispersal over tens of kilometres from its current populations. Not known from Great Britain. ECOLOGY A species of valley mires, along brooks and small rivers and fenland. Males hover in sunlit spots above brooks in forest. Larval biology unknown, but likely aquatic. COMMENT Recently synonymised with E. obscura, but this name belongs to the North American population that is genetically (and morphologically) clearly a different species.

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ptero sti g m a l ong

d a rk spo t v e ry l a rge bl a ck spo t a bdo m e n e nti re l y shi ny

tip pointe d ba se ye l l o w

l obes w e a k l y cu rved

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p aramere lateral

h i n d f e mu r

paramere f ront view

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a b d o me n

sm a l l spo ts dark s pot

de nse l y duste d

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fan- s hape d me mb ra n e a t ti p

sc u tu m

sw o l l e n a nd sl i ghtl y curv e d

l obes strongl y cu rved

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p aram ere lat eral

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h i n d f e mu r

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h i n d f e mu r

ba sa l ha l f ye l l o w

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Spot-winged Drone Fly Eristalis rupium IDENTIFICATION 10–13 mm. Dark medium-sized Eristalis with,

especially in female, a large blackish spot on wing. Face with wide black medial stripe, remainder of face below dusting black, in female rarely dark yellow; arista with long hairs. Scutum in male with orange–red hairs, in female hairs yellow–orange; scutum dull; scutellum with band of black hairs. Wing: with dark band or spot in middle, in female spot may be large, squarish; pterostigma 3–3.5 times longer than wide; vein R4+5 sinuous. Sternites 2–4 shiny. Male: posterior part of fore femur largely covered with black hairs; base of hind femur usually black; yellow spots on sides of tergite 2 shiny, black space between spots dull; tergites 3 and 4 at least on posterior half with black hairs; genitalia: lobes on aedeagus weakly curved, paramere in side view with pointed tip. Female: base of hind femur usually narrowly yellow; tarsomere 1 of hind tarsus yellow; pair of spots on tergite 2 small or absent; all tergites shiny; tergite 4 with long erect hairs; tergites 3 and 4 almost entirely or entirely covered with black hairs. SIMILAR SPECIES Always has dark markings on wing, and thus can be confused with E. horticola, E. jugorum, E. alpina, E. picea and E. pseudorupium. For differences with first three, see those species. Forms trio of very similar species with E. picea and E. pseudorupium, but identification not too difficult; indicative characters are more reddish hairs on scutum and larger spot on wing; more reliable characters are longer pterostigma, shiny sternites, shiny tergites in female and weakly curved lobes on aedeagus in male; differs further from E. picea by scutellum more extensively covered with black hairs. OCCURRENCE A northern species that generally occurs in upland areas in region covered

by this book. Its range in Belgium has contracted recently. In Great Britain, local in north and west only. ECOLOGY Fen, marsh, brooks in meadows, valley mires in woodland, especially on peat, and where plants such as Water avens and Marsh cinquefoil are present. Often seen visiting white umbellifers and Devil’s-bit scabious. Larva lives in wet peat, usually near running water.

Dusted Drone Fly Eristalis alpina IDENTIFICATION 11–14 mm. Medium-sized, greyish Eristalis.

Face with black medial stripe, remainder of face with thick silver–white dusting, ground colour under dusting black in male, black or yellow in female; arista with long hairs. Scutum with whitish hairs; anterior half of scutum dusted, contrasting with shinier posterior half, especially distinctive in female; scutellum with long white hairs. Wing: male with sometimes-indistinct dark band in middle, in the female, a much wider and squarish spot; pterostigma about twice as long as wide; vein R4+5 sinuous. Hind femur swollen and slightly curved, especially distinctive in male; about basal half of hind femur yellow in female, in male the yellow part smaller or absent; posterior part of fore femur with pale hairs; basal two tarsomeres yellow, sometimes dark yellow in male. Abdomen quite slender in male, conical; abdomen black except two small pointed side spots on tergite 2, sometimes spots absent in female, side spots shiny but space between spots dull; tergites 3 and 4 with dull anterior and posterior margins in male, with dull posterior margin in female; posterior half of tergites 3 and 4 with black hairs. Male: lobes on aedeagus strongly curved, paramere with fan-shaped membrane at tip. SIMILAR SPECIES The only Eristalis with a swollen and slightly curved hind femur, but this is less distinct in female, so use other characters as well. The combination of more whitish instead of orange–yellow body hairs and dusted scutum gives this species a greyer appearance. Unlike in E. horticola and E. jugorum, tergites 3 and 4 extensively covered with black hairs. Like the trio E. rupium, E. picea and E. pseudorupium, but in male posterior side of fore femur with white hairs and female with hind femur more extensively yellow and scutum (anteriorly) with denser dusting; female furthermore differs from E. picea by dull area between spots on tergite 2 and

from E. pseudorupium by white hairs on scutellum. If spot on wing is indistinct in male, can be confused with E. nemorum but hind femur swollen, pterostigma longer and basal tarsomeres pale. OCCURRENCE A very local species in European mountain ranges. Not known from Great Britain. ECOLOGY Along strongly meandering small streams near forests, valley mire. Visits flowers along water’s edge and forest edge. Larval biology unknown.

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♂ ta rsi b l a ck

d i sti n ct d a rk spo t

ora n ge sp o ts

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bo dy ha i rs e nti re l y ye l l o w -w hi te

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bas e fore and mid tars us us ually ye llow

a b d o me n

a b d o me n

i n di sti nct da rk sp o t

pa l e r ha i re d i ndi v i dua l

ca l yp ter g rey-bl a ck dark - haire d individual

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wing hyaline

a b d o me n

wi n g

da rk spo t

cal ypte r a nd sc ute l l um w hi te

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a b d o me n

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Orange-spotted Drone Fly Eristalis anthophorina IDENTIFICATION 10–12 mm. Medium-sized hairy Eristalis. Known

as a furry bumblebee mimic, but orange spots on abdomen are still easily visible through hairs. Face with wide black medial stripe; arista with short hairs. Scutum and abdomen with long, entirely yellow–white hairs. Wing: vein R4+5 sinuous; cell r1 closed; with distinct dark spot in middle. Legs entirely black except knees and basal third of tibiae. Abdomen with pairs of orange spots on tergites. SIMILAR SPECIES One can easily look through the light body hairs, so could be confused with short-haired Eristalis; combination of long yellow–white body hairs, arista with short hairs, face with black medial stripe, wing with distinct black spot in middle and black legs except pale knees and base of tibiae distinguishes it from all bee-mimicking Eristalis. The bumblebeemimicking Eristalis, that is, E. intricaria and E. oestracea, are much darker: E. oestracea has scutum extensively covered with black hairs and abdomen without pairs of orange spots; E. intricaria can have mostly (dark) orange hairs, not yellow–white, and in

E. intricaria sides of thorax with black hairs, arista with longer hairs and usually base of fore and mid tarsi pale. OCCURRENCE A very local species south of Denmark, declining in the southern part of its range. Not known from Great Britain. ECOLOGY In the Netherlands and northern Germany along ditches and pools in lowland fen areas, in Denmark also along ponds and lakes. Usually flies fast above densely vegetated ditches and visits flowers of, for example, Yellow water-lily, white umbellifers and brambles. Larva probably lives in water among decaying organic matter.

Furry Drone Fly Eristalis intricaria IDENTIFICATION 11–14 mm. A common bumblebee-mimicking

Eristalis. Face with black medial stripe; arista with long hairs. Sides of thorax with black hairs; scutellum orange; colour of hairs on body variable: scutum and abdomen almost entirely with orange–brown hairs, but sometimes hairs largely black and only tip of abdomen with yellow–white hairs (variation furva). Wing: vein R4+5 sinuous; cell r1 closed; usually with dark band in middle; calypter grey–black. Male: tergites 2 and 3 with pairs of orange spots, visible through dense hairs when viewed from behind. SIMILAR SPECIES Recognised as an Eristalis by combination of vein R4+5 sinuous and closed cell r1. In Eristalis can be confused only with other two bumblebee mimics, E. anthophorina and E. oestracea; differs from both in having grey–black instead of white calypter and long hairs on arista; other differences with E. anthophorina include body with darker hairs, at least at sides of thorax with black hairs; other differences with E. oestracea include black hind tarsus and orange scutellum. OCCURRENCE Widespread and locally common. ECOLOGY Swampy wetlands, wet woodland, fen carr, marshes, eutrophic fens and bogs, but mobile so can

appear in a great variety of dry, flowery habitats including gardens. In spring, males often hover 2–8 metres above ground around flowering willows, Blackthorn etc., often with the abdomen tip glowing brightly in the sun. Visits flowers such as thistles, Devil’s-bit scabious, white umbellifers and Common heather, also blossoming scrubs and trees in spring. Larva lives in semi-liquid nutrient-rich organic environments: cow dung on mud, fen peat and slurry.

Orange-tailed Drone Fly Eristalis oestracea IDENTIFICATION 13–16 mm. A large bumblebee mimic. Face with narrow black medial stripe; arista with short hairs. Scutum and middle part of abdomen with black hairs, scutellum and base of abdomen with white hairs, tip of abdomen with orange–yellow hairs; scutellum whitish. Wing: transparent in male, in female with dark central spot; vein R4+5 sinuous; cell r1 closed; calypter pale. Anterior and posterior part of hind tibia feather-like with dense hairs pointing towards tip; hind tarsus orange. SIMILAR SPECIES Could be confused with other bumblebee-mimicking hoverflies like Eriozona syrphoides or Merodon species but combination of vein R4+5 sinuous and closed cell r1 distinguishes it from all except the other two bumblebee-mimicking species of Eristalis, E. anthophorina and E. intricaria; differs from E. anthophorina by scutum and abdomen extensively covered with black hairs and from E. intricaria by shorter hairs on arista, white scutellum and yellow hind tarsus. OCCURRENCE Widespread but very rare in Denmark, very rare in northern Germany but not further south. Not known from Great

Britain. ECOLOGY Nutrient-poor marshes, near lakes and streams. Usually flies low and fast above the water and visits flowers at the water’s edge. Larval biology unknown but likely aquatic.

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a b d o me n

a nte nna o ra nge

a l l ti bi a e ora n ge

♂

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head

a b d o me n

♂

a bdo m e n co nv e x fals e ve in abs e nt

e ye s w i de l y se pa ra te d

e ye s e nti re l y ha i re d

♂

♂

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face

a b d o me n

a bdo m e n pa ra l l e l si de d fals e ve in pre s e nt

e ye s to uchi ng

e ye s ha i re d o nl y o n uppe r pa rt

♂

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Bog-dwelling Drone Fly Eristalis cryptarum IDENTIFICATION 9–13 mm. Small compact dark Eristalis with

red spots on abdomen. Face slightly protruding, with wide black medial stripe; antennae entirely bright orange; arista with short hairs. Scutum with orange–red hairs. Wing: base brown infuscated and with orange veins; indistinct brown spot in middle; vein R4+5 sinuous; cell r1 closed. Base of femora and outer two tarsomeres black, remainder of legs bright orange. Tergite 2 with large darkorange pair of spots, usually tergite 3 black in female, in male with small pair of orange spots; tergites 2–4 with white–yellow posterior margin. SIMILAR SPECIES Easily recognised: the only Eristalis with bright orange tibiae and antennae; in other Eristalis, third antennal segment may be pale below but not entirely bright orange and tibiae with at least tip dark. OCCURRENCE Sharply decreased in North-west Europe, extinct in Belgium and the Netherlands, extremely local in Denmark and rare in Great Britain (now only Dartmoor). ECOLOGY Heath moors, mossy seepages and soakways in moorland and associated mire, often near ponds

or streams, valley mire in heathland and moorland. Flies low and fast above the vegetation and visits low flowers such as those of Common heather, Devil’s-bit scabious, Bogbean and Common tormentil. Larval ecology unknown, but egg-laying was observed on and close to very fresh cow dung along oligotrophic seepages in moorland.

Black Lagoon Fly Eristalinus sepulchralis IDENTIFICATION 7–10 mm. Fairly small black fly with spotted eyes. Face, except facial tubercle, with silver–white dusting; eyes greenish with red–brown spots; eyes entirely covered with hairs. Scutum in female with five grey dull longitudinal stripes, in male less distinct, sometimes hardly discernible or only visible on anterior part. Wing: without false vein; vein R4+5 sinuous. Hind femur and hind tibia slightly curved; hind femur swollen in male; tip of hind femur usually black. Tergites 2 and 3 on top largely dull in male, in female without or with only small dull parts. Male: eyes widely separated. SIMILAR SPECIES Owing to combination of black abdomen and spotted eyes, can be confused only with E. aeneus, but first impression already different: smaller, stockier, with black sheen and abdomen more conical (males) or convex (females); males, furthermore, easily distinguished by widely separated eyes; reliable character for both sexes is hairs covering entire eye, only upper part with hairs in E. aeneus; other differences more subtle: top of tergites 2 and 3 duller, wing lacks false vein, usually tip of hind femur black, hind femur and hind tibia slightly curved and scutum with grey-dusted longitudinal stripes (but see at

E. aeneus). OCCURRENCE A widespread and frequent species in lowland areas. ECOLOGY A wide range of habitats but especially wetlands and farmland with ditches and ponds but clearly very mobile, so adults will appear well away from breeding sites. Flies very actively through vegetation and visits ragworts, thistles, mayweeds and other composites. Larva lives in pools with decaying organic matter but also in wet manure.

Common Lagoon Fly Eristalinus aeneus IDENTIFICATION 10–12 mm. An entirely dark fly with spotted eyes. Face, except facial tubercle, with silver–white dusting; eyes with hairs only on upper part, about lower two-thirds bare; eyes greenish with red–brown spots; third antennal segment usually orange, sometimes upper part dark. Markings on scutum variable: usually entirely shiny, sometimes with dull longitudinal stripes at base. Wing: false vein present, although often indistinct; vein R4+5 sinuous. Tip of hind femur yellow; hind femur and hind tibia not distinctly curved, hind femur slightly swollen. Body black with bronzy sheen; tergites 2 and 3 entirely shiny. Male: eyes meeting. SIMILAR SPECIES Owing to combination of black abdomen and spotted eyes, can be confused only with E. sepulchralis. Male easily distinguished from E. sepulchralis by eyes meeting, moreover, in both sexes only upper third with sparse hairs while fully haired in E. sepulchralis; for more differences, see E. sepulchralis. In the area covered by this book, scutum mainly shiny, but further south in Europe usually with same grey dull longitudinal stripes as female E. sepulchralis, although transverse suture still shiny, versus dusted

in female E. sepulchralis. OCCURRENCE Widespread in coastal areas, but can be common as well at inland locations in the south of the range covered by this book but only occasionally inland in Great Britain. ECOLOGY Saltmarsh edge, saline lagoon, rocky shores, brackish ditches and drains. Occasionally inland along large rivers, spoil tips and old quarries. Flies low and visits a variety of flowers, often sits on the ground. Males defend territories very aggressively and noisily, often from a stone perch. Both sexes hibernate as adult, in cavities or indoors, and can appear on mild winter days. Larva lives in brackish pools with decaying organic matter including seaweed.

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a b d o me n

p a ttern re se m bl e s a skul l o r the Ba tma n l o go

ce ll r 1 ope n

♂

sc u tu m

dusti ng o n scutum so m e ti m e s re duce d

♂

♀

a b d o me n

dark s pot

ce l l r 1 o pe n e ye ba re

stro ngl y sw o l l e n

♂

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dark s pot

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h i n d f e mu r

♂

eyes wi d el y sep a ra te d

head

head

v e i n R 4+ 5 si nuo us

e ye ha i re d

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Common Batman Fly Myathropa florea IDENTIFICATION 10–14 mm. A distinctive robust black-andyellow hoverfly. Eyes with short hairs; arista bare. Scutum with grey–yellow dusting, pattern resembling a skull or the Batman logo; in dark individuals, dusting on scutum restricted to transverse suture and posterior margin. Wing: cell r1 open; vein R4+5 sinuous. Abdomen with pairs of bright-yellow spots. SIMILAR SPECIES Brightly coloured individuals easily recognised by combination of large bright-yellow spots on abdomen and pattern of dusting on scutum; darker individuals have less distinct dusting on scutum and resemble Eristalis species but cell r1 open. OCCURRENCE A widespread and common species, especially near woodland. ECOLOGY In the vicinity of broad-leaved forest, but also abundant in more open habitats such as gardens and parks. Males occupy a territory in the forest edge on leaves or near a flowering bush, chasing other insects. Larva is aquatic and lives in tree cavities but also water-filled car tires and cow dung on waterlogged soil. COMMENT Recent not-yet-published

DNA research reveals that Myathropa florea is in fact a species complex, with two species occurring in North-west Europe. Both species allegedly are common. Details about identification are still lacking, but the strikingly dark specimens with little dusting on scutum appear to be a different species from the specimens with clear dusting on scutum. Hopefully more details will become available in the coming years.

Northern Bee Mimic Mallota cimbiciformis IDENTIFICATION 15–17 mm. Large, convincing bee mimic. Face with fairly wide black medial stripe; eyes bare; third antennal segment short, kidney-shaped and extended downwards; arista bare, orange. Scutum and scutellum with dense yellow hairs; scutellum translucent yellow. Wing: with brownish band in middle; cell r1 open; vein R4+5 sinuous. Hind femur strongly swollen, with a row of long bristly hairs below at tip; legs black and dark yellow. Abdomen with short white–yellow hairs, black ground colour well visible. Male: eyes barely meeting. SIMILAR SPECIES Not at all like M. fuciformis, which has hairs on eyes and is a bumblebee mimic. Similar to other bee-mimicking species like Criorhina asilica, C. pachymera and Brachypalpus, but these species with vein R4+5 not sinuous. Merodon species have vein R4+5 sinuous but are smaller, lack spot on wing and have a triangular process below at tip of hind femur. Perhaps most similar to the much commoner E. tenax owing to similar posture and size, but that species has hairs on eyes, cell r1 closed and lacks strongly swollen hind femur. OCCURRENCE A widespread but very rare species throughout North-west Europe, but seemingly commoner in Great Britain.

Searching for larvae can be more rewarding than looking for adults. ECOLOGY Broad-leaved forests and historical parkland with old trees. Presumably largely arboreal, comes down only to feed. Visits flowering bushes and white umbellifers; males fly very fast in zigzag pattern around the flowers. Males sit next to the entrance of water-filled tree cavities awaiting females. Larva lives in waterfilled tree cavities, usually with a narrow entrance. Most often found in beech and sycamore, possibly because these trees more often have rot holes. COMMENT Mallota are enigmatic hoverflies combining rarity, being indicators of rich old tree habitats, sheer beauty and stunning mimicry.

Bumble Mimic Mallota fuciformis IDENTIFICATION 14–16 mm. Beautiful bumblebee mimic. Head relatively small, face protruding downwards; eyes with long black hairs; face entirely black with long black hairs; frons and vertex with distinctive long yellow hairs; antennae black, arista orange. Hairs on scutum and abdomen black, but hairs on scutellum, tergite 2 and sometimes base of scutum yellow–white; tip of abdomen with reddish hairs. Wing: with dark spots, at base and in middle; cell r1 open; vein R4+5 sinuous. Femora and tibiae black, tarsi brown or black. Male: eyes widely separated. SIMILAR SPECIES Not at all like M. cimbiciformis, which has bare eyes and is a bee mimic. Similar to other bumblebee-mimicking hoverflies, but wing venation distinguishes it from most of them: vein R4+5 sinuous and cell r1 open; only other bumblebee mimic with same wing formula is Merodon equestris but that species with different colour distribution of body hairs and has a triangular process below at tip of hind femur. The only species with very long yellow hairs on frons and vertex, a useful field character. OCCURRENCE This species had disappeared by the second half

of the 20th century from Belgium and the Netherlands, but by the 21st century has returned and spread widely. Not known from Great Britain. ECOLOGY Broad-leaved forests and historical parkland with overmature trees. A significant proportion of observations comes from urban areas and large cities, probably reflecting higher tree age (which correlates strongly with the presence of rot holes) in historical city parkland compared to in most forests. Possibly largely arboreal, but comes down to visit flowering bushes such as Blackthorn, cherry species and willow, usually found high in the bush. Males fly swiftly through the twigs. Larva has been reared from cavities of old broad-leaved trees including beech.

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a b d o me n

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stro ngl y pro trudi ng

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a b d o me n

a nte ri o r m a rgi n o f spo ts cl e a rl y curv e d

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head

no t stro ngl y pro trudi ng a n teri o r m a rg i n of terg i te 4 bl a ck

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a b d o me n

a nte ri o r m a rgi n o f spo ts w e a k l y curv e d

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head

f a ce pro trudi ng a nteri o r m a rg i n of sterni te 4 l a rg el y d usted

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Snouted Duck Fly Eurimyia lineata IDENTIFICATION 8–9 mm. A fly with a remarkable pointed face. Face long and strongly protruding into a point; third antennal segment largely or entirely orange. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. Hind tibia orange with black rings at base and tip; central third of hind femur black on upper part. Abdomen narrower than or as wide as thorax. Male: eyes widely separated; hind femur below without extra swelling at base; tergites 2 and 3 with pair of yellow, roughly triangular spots. Female: tergites 2–4 with slightly curved, yellow or grey stripes. SIMILAR SPECIES The long, strongly protruding pointed face distinguishes it from all similar species. Anasimyia lunulata has a protruding face too, but face is shorter and with a blunt end; when in doubt, E. lineata differs from all Anasimyia by having upper part of central third of hind femur black instead of orange. OCCURRENCE A widespread and often common species in wetlands. ECOLOGY A variety of swampy wetlands, including eutrophic lowland ponds, fens, boggy pools in valley mire and

the edges of raised bogs, though it avoids the more acidic parts of bogs and tends to occur where plants such as Yellow flag and Water mint are present. Frequently visits flowers as buttercups, Bogbean or Water mint. Larva lives in submerged decaying plant material near emergent vegetation.

Ditch Swamp Fly Anasimyia interpuncta IDENTIFICATION 8–11 mm. Face not distinctly protruding, with yellow dusting, without bare black or yellow medial stripe; third antennal segment orange. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. At least basal three-quarters of upper side of hind femur orange; hind tibia yellow with, sometimes indistinct, black rings at base and tip. Abdomen narrower than or as wide as thorax; pairs of spots on tergites 2–4 angled, not hook-shaped, not pointing forwards. Male: eyes widely separated; hind femur below without extra swelling at base; anterior margin of tergite 4 black and undusted for most of its width. Female: anterior margin of grey pair of spots on tergite 4 clearly curved; tergite 5 entirely covered with yellow hairs. SIMILAR SPECIES Like Helophilus species, but third antennal segment orange and face without bare medial stripe. Differs from Parhelophilus by narrower abdomen and two dark rings on hind tibia. Lacks pointed snout of Eurimyia lineata. Pairs of spots on tergites 2 and 3 not pointing forwards and not stalked like in A. transfuga and A. contracta; moreover, in male hind femur below without distinct bulge near base. It mainly resembles

the much rarer A. lunulata; for differences, see that species.

OCCURRENCE Northern Europe south to northern France, but

widespread in wetlands in northern Belgium and the Netherlands. ECOLOGY Pools and ditches in the alluvial plain, freshwater to mildly brackish ditches in the coastal plain, with lush emergent vegetation, especially where Reed sweet-grass swamp is present. Males fly fast and low above the water. Frequently visits flowers at the water’s edge. Larva has an aquatic lifestyle.

Bogbean Swamp Fly Anasimyia lunulata IDENTIFICATION 7–10 mm. Face protruding, but not pointed; face with yellow dusting, without bare black or yellow medial stripe; third antennal segment orange. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. At least basal threequarters of upper side of hind femur orange; hind tibia yellow with, sometimes indistinct, black rings at base and tip. Abdomen narrower than or as wide as thorax; pairs of spots on tergites 2–4 angled, not hook-shaped, not pointing forwards. Male: eyes widely separated; hind femur below without extra swelling at base; anterior margin of tergite 4 heavily dusted yellowish grey for almost its entire width, only narrowly black and undusted in middle. Female: anterior margin of grey pair of spots on tergite 4 weakly curved; tergite 5 with some black hairs intermixed in yellow ones. SIMILAR SPECIES For differences with species other than A. interpuncta, see that species. Much like A. interpuncta, but face further protruding, male has anterior margin of tergite 4 heavily dusted for almost its entire width and female has tergite 5 partly covered with black hairs and pair of spots on tergite 4 with

anterior margin less curved. OCCURRENCE Has sharply declined in North-west Europe over the past century. Scarce in Great Britain where it shows a western bias. ECOLOGY Boggy pools, valley mire, quagmire, always in the vicinity of Bogbean. Flies low over the water surface or settles on nearby vegetation, usually Bogbean. Visits the flowers of Bogbean. Larval biology unknown, but larva likely aquatic and associated with Bogbean.

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spo ts f urthe r re m o v e d f ro m e a ch o the r tha n f ro m a nte ri o r m a rgi n te rgi te no t co nstri cte d

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ste rn i te s

shi ny l o ngi tudi na l stri pe

di sta nce o f spo ts to a nte ri o r m a rgi n te rgi te i s l a rge r tha n di sta nce be tw e e n spo ts

co nstri cte d

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a b d o me n

a bdo m e n w i th l o ngi tudi na l stri pe s

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Golf-club Swamp Fly Anasimyia transfuga IDENTIFICATION 9–11 mm. An Anasimyia with hook-shaped

spots on abdomen. Face not much protruding; face with yellow dusting, without bare black or yellow medial stripe; third antennal segment orange. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. At least basal three-quarters of upper side of hind femur orange; hind tibia yellow with, sometimes indistinct, black rings at base and tip. Abdomen narrower than or as wide as thorax; sides of abdomen straight, grey or yellow markings on tergites 2 and 3 hook-shaped: constricted in middle and tip pointed forwards. Male: eyes widely separated; hind femur below with distinct bulge near base; sternites 2 and 3 entirely dull, without shiny medial longitudinal stripe. Female: tergite 2 with gap between anterior edge of pale markings to anterior margin of tergite less than gap between pale markings. SIMILAR SPECIES For differences with Helophilus and Parhelophilus, see A. interpuncta. The hook-shaped spots on abdomen occur in Anasimyia only also in A. contracta. Much like A. contracta but usually larger

and more robust, has tergite 2 not constricted, male without shiny longitudinal stripe on sternites 2 and 3 and female has pattern of spots on tergite 2 subtly different: gap between anterior edge of pale markings to anterior margin of tergite less than gap between pale markings, opposite to A. contracta. OCCURRENCE Widespread. More coastal and more frequent on alluvial plains than A. contracta. ECOLOGY At the edge of rather nutrient-rich ponds and ditches with lush emergent vegetation of bur-reeds and Yellow iris. Flies low above the water surface and frequently visits flowers along the water’s edge. Adults rest on emergent vegetation and males seem to hold small territories. Larva has an aquatic lifestyle.

Waisted Swamp Fly Anasimyia contracta IDENTIFICATION 7–11 mm. An Anasimyia with hook-shaped

spots on abdomen. Face not much protruding; face with yellow dusting, without bare black or yellow medial stripe; third antennal segment orange. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. At least basal three-quarters of upper side of hind femur orange; hind tibia yellow with, sometimes indistinct, black rings at base and tip. Abdomen narrower than or as wide as thorax; grey or yellow markings on tergites 2 and 3 hook-shaped: constricted in middle, tip pointed forwards; tergite 2 constricted, although not always distinct in male. Male: eyes widely separated; hind femur below with distinct bulge near base; sternites 2 and 3 dull with shiny longitudinal stripe in middle. Female: tergite 2 with gap between anterior edge of pale markings to anterior margin of tergite larger than gap between pale markings. SIMILAR SPECIES For differences with Helophilus and Parhelophilus, see A. interpuncta. Unlike A. interpuncta and A. lunulata, the pairs of spots on tergites 2 and 3 are hook-shaped and point forwards at tip, and in male hind femur below with distinct bulge near base. Much like A. transfuga; for differences,

see that species. OCCURRENCE Widespread in wetlands featuring bulrush. On average, less in floodplains and more in base-poor but nutrient-rich environments than A. transfuga. ECOLOGY Fenland, quagmire, marshes, often near bushes or forest. Males keep territory in the vegetation, females fly low above the water or through the vegetation. Visits flowers at the water’s edge. Larva has an aquatic lifestyle and has been found between the leaf sheaths of bulrush.

Clubrush Fly Lejops vittatus IDENTIFICATION 12–13 mm. A dark hoverfly with unique

pattern on abdomen. Face with black medial stripe; antennae black. Scutum dull black with grey longitudinal stripes. Wing: vein R4+5 sinuous. Side margins of tergite 2 yellow; tergites 2–4 with yellowish to greyish longitudinal stripes. Male: eyes widely separated. SIMILAR SPECIES Closely related to Anasimyia, sharing grey longitudinal stripes on scutum, but pattern of yellowish to greyish longitudinal stripes on tergites 2–4 unique. OCCURRENCE Has suffered strongly from the sad fate of estuaries throughout Europe. Now very localised. In Great Britain, mostly associated with coastal grazing marsh of southeast England. ECOLOGY Along brackish ditches, borrow dykes and lagoons in coastal levels and vegetated shingle systems where Sea clubrush is present, often those directly behind a sea wall where some sea water leaches through. Needs permanent standing water, not present in ditches or pools that are prone to drying out. Mainly found resting on flowering Sea clubrush. Also active in adverse weather. Larva aquatic,

presumably living among decaying plant debris from Sea clubrush.

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f o re ti b i a

a b d o me n

a t m o st w i th va gue m a rk , no t bl a ck a l l -a ro und

ye l l o w -ha i re d ye l l o w -ha i re d

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hind fem ur

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he a d

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a b d o me n

fo re ti b i a y e l l o w

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ro w o f bl a ck ha i rs ro w o f bl a ck ha i rs

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tubercl e wi th b l a ck b ri stl es

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he a d

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a b d o me n

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stri pe s no t co nne cte d

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f o re ti b i a

ti p bl a ck a l l -a ro und

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head

f a ce sl i ghtl y pro trudi ng

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Marsh Stripeback Parhelophilus versicolor IDENTIFICATION 9–11 mm. Face with yellow dusting and shiny thin yellow medial stripe; face not much protruding; third antennal segment orange; hairs on upper part of occiput yellow. Scutum dull brown–black with grey–yellow longitudinal stripes; scutellum dull. Wing: vein R4+5 sinuous. Fore tibia entirely yellow or with a black marking on inner side of tip; hind tibia yellow except black tip; hind femur below at tip with a few long pale hairs. Abdomen wider than scutum; tergites with pairs of orange–yellow spots and yellow–grey dust spots, in male usually larger than in female where orange spots occasionally may be absent. Male: eyes widely separated; base of hind femur below without tubercle. Female: black hairs on posterior half of tergite 4 semi-adpressed. SIMILAR SPECIES Can be confused with Helophilus but smaller, furrier, face without wide bare medial stripe and third antennal segment orange. Abdomen yellower and wider than in Anasimyia (but some females have only greyish spots); moreover, base of hind tibia usually without

black ring. Like P. frutetorum and P. consimilis; for differences, see those species. OCCURRENCE A widespread species in lowland wetlands where it can be common. ECOLOGY Swampy wetlands such as marshes, streams and ditches with broad belt of emergent vegetation, usually in the vicinity of bulrushes or bur-reeds. Visits flowers of marsh plants, or nearby blossoms, brambles or umbellifers. Mobile species that can be found far from water. Larva lives in water among decaying plants, for example, bulrush.

Tuberculate Stripeback Parhelophilus frutetorum IDENTIFICATION 8–10 mm. Face not much protruding; face with yellow dusting and shiny thin yellow medial stripe; third antennal segment orange; upper part of occiput with a row of black hairs among yellow hairs. Scutum dull brown–black with grey–yellow longitudinal stripes; scutellum dull. Wing: vein R4+5 sinuous. Fore tibia entirely yellow or with a black marking on inner side at tip; hind tibia yellow except black tip; hind femur below at tip with a few long pale hairs. Abdomen wider than scutum; pairs of orange–yellow spots with yellow–grey dust spots on tergites variable, in male usually larger than in female where orange spots may be greatly reduced. Male: eyes widely separated; base of hind femur below with tubercle with tuft of black bristles. Female: black hairs on posterior half of tergite 4 erect. SIMILAR SPECIES For differences with Helophilus and Anasimyia, see P. versicolor. Like P. consimilis; for differences, see that species. Very similar to P. versicolor but male has base of hind femur below with distinctive tubercle with tuft of black bristles; identification of females less straightforward, but upper part of occiput with a row of black hairs (also present

in males) and black hairs on posterior half of tergite 4 erect. OCCURRENCE A widespread species in North-west European lowlands. ECOLOGY Mainly alluvial forest or forest with pools and ditches, but also wetlands habitats with lush vegetation; the Parhelophilus most likely to be encountered in drier habitats. Visits several flowers such as brambles, Cow parsley or hogweed. Larva lives in mud with decaying organic matter.

Black-ankled Stripeback Parhelophilus consimilis IDENTIFICATION 8–10 mm. A Parhelophilus with relatively

small yellow spots on abdomen. Face distinctly protruding; face with yellow dusting and shiny thin yellow medial stripe; third antennal segment orange. Scutum dull-black with grey– yellow longitudinal stripes; scutellum shiny. Wing: vein R4+5 sinuous. Fore tibia at tip black all around; hind femur below at tip without long pale hairs; hind tibia yellow except black tip. Abdomen wider than scutum; pairs of yellow spots with greyish dust spots on tergites variable, in male usually larger than in female; tergite 1 with a clearly separated pair of grey-dusted, oblique stripes. Male: eyes widely separated. SIMILAR SPECIES For differences with Helophilus and Anasimyia, see P. versicolor. A reliable character to distinguish it from the similar P. frutetorum and P. versicolor is fully black tip of fore tibia, which is entirely yellow or at most with a black mark on inner side in other two; other differences include blacker ground colour of scutum, shiny scutellum, more protruding face, shorter pale hairs on tip of hind femur and pair of interrupted dusted

stripes on tergite 1, versus fused and semicircular stripes in the other two species (especially P. frutetorum). OCCURRENCE A very local species in North-west Europe, has declined sharply in the range covered by this book. In Great Britain, mostly western. ECOLOGY Old peaty wetlands including base-poor fenland, transition mire and valley mire, at the edges of raised bog. Generally close to water. Flies fast through high-water vegetation or sits on sunlit leaves; often in the vicinity of Marsh cinquefoil. Visits flowers such as Yellow flag, thistles or umbellifers. Larval biology unknown, but certainly aquatic.

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tw o -thi rds o ra nge

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bl a ck m e di a n stri pe

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a b d o me n

fore ta rsus bl a ck hi nd m a rgi n ye l l o w hind leg

ba sa l thi rd o ra nge

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l a rg e sp o ts bl a ck m e di a n stri pe

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a b d o me n

hi nd m a rgi n usua l l y ye l l o w hind leg

ba sa l thi rd o ra nge

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Tiger Marsh Fly Helophilus pendulus IDENTIFICATION 11–13 mm. A small to medium-sized and common Helophilus. Face with shiny black medial stripe; antennae dark brown to black. Scutum dull black with grey longitudinal stripes; scutum with yellow hairs. Wing: vein R4+5 sinuous. Fore tarsus dark brown to black; tip of hind femur orange for about a third, basal two-thirds of hind tibia orange. Posterior margin of tergites yellow. Male: eyes widely separated; compared to female, tergite 3 more extensively yellow at anterior margin. Female; spots on tergite 3 gradually narrowing to their inner point. SIMILAR SPECIES Like Parhelophilus and Anasimyia species, but third antennal segment dark brown to black and face with distinct black medial stripe. Differs from other Helophilus by hind leg more extensively pale: tip hind femur orange for about a third, in other species at most a narrow orange band just before tip; basal two-thirds of hind tibia orange, in other species for only one-third. Additional differences: differs from H. trivittatus by black instead of pale medial stripe on face; in male, yellow markings on abdomen

less extensive compared to H. hybridus; unlike in H. affinis and H. groenlandicus, posterior margin of tergites yellow. OCCURRENCE A very widespread and common hoverfly over most of Europe. ECOLOGY Strictly speaking, a wetland species but is able to use a wide range of standing water and sub-aqueous habitats, also very mobile so can fly considerable distances from breeding sites. Forests, marshes, grasslands, parks and gardens. Flies low above vegetation and frequently visits flowers. Males do not defend territories but hover above resting females. Larva lives in wet decaying organic matter.

Woolly-tailed Marsh Fly Helophilus hybridus IDENTIFICATION 13–16 mm. A fairly large dark-yellow Helophilus.

Face with wide shiny black medial stripe; antennae dark brown to black. Scutum dull black with grey longitudinal stripes; scutum with yellow hairs. Wing: vein R4+5 sinuous. Fore tarsus black; hind femur black except for small orange spot or band just before tip; one-quarter to one-third of base of hind tibia orange. Posterior margin of tergites narrowly yellow. Male: eyes widely separated; extensive yellow markings on tergites 2 and 3 connected, without black transverse band on posterior margin of tergite 2. Female: abdominal spots usually dirty yellow, not bright yellow; spots on tergite 3 usually narrowing to inner side only in their last third. SIMILAR SPECIES Like Parhelophilus and Anasimyia species, but third antennal segment dark and face with wide black medial stripe. Like H. trivittatus but face with black medial stripe; like H. pendulus but hind femur and hind tibia less extensively orange, female with fewer pointy spots on tergite 3 and male with more extensive yellow markings on abdomen; like H. affinis but fore tarsus entirely black and posterior margin of tergites 3–5 yellow; like H. groenlandicus but scutum with yellow hairs and posterior

margin of tergites 3–5 yellow. OCCURRENCE Has colonised most of North-west Europe since 1940. ECOLOGY Moist, half-open to open habitats, marshes, forest ditches. More restricted to aquatic habitats compared to other Helophilus. Visits large array of flowers. Larva has an aquatic lifestyle in decaying organic matter.

Lemon Marsh Fly Helophilus trivittatus IDENTIFICATION 14–18 mm. A large Helophilus with lemon-

yellow rather than buff markings on tergites. Face with yellow shiny medial stripe, remainder of face yellow as well but with white dusting and hairs; pale medial stripe sometimes brownish around facial tubercle; antennae black. Scutum dull black with grey longitudinal stripes; scutum with yellow hairs. Wing: vein R4+5 sinuous. Fore tarsus pale or partly dark; hind femur black except for small orange spot or band just before tip; one-quarter to one-third of base of hind tibia orange. Spots on abdomen lemon yellow and relatively large in male, sometimes very small in female; posterior margin tergites 3 and 4 narrowly yellow or sometimes black; pair of stripes on tergite 4 usually connected, forming a W-shaped marking (male) or an undulating band (female). Male: eyes widely separated. SIMILAR SPECIES Like Parhelophilus and Anasimyia species, but third antennal segment dark and black markings on legs different. Most reliable character to distinguish H. trivittatus from the other Helophilus is shiny bare yellow medial stripe on face, at most brownish at facial

tubercle, but never with black medial stripe as in other species; furthermore, stands out by larger size, markings on abdomen lemon yellow and male by W-shaped marking on tergite 4. OCCURRENCE Widespread. Numbers can fluctuate strongly between years, in response to weather events (for example, large-scale flooding) or influxes. ECOLOGY Open habitats, marshes, agricultural fields, grasslands, flowery meadows, but as a migrant can appear everywhere. Flies low and quickly above vegetation. Often to be found on purple thistles. Larva lives in all sorts of wet environments with decaying organic matter.

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a b d o me n

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ba sa l thi rd o ra nge

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fore ta rsus b l a ck

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face

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a b d o me n

♂ hind leg

hi nd m a rgi n bl a ck

ba sa l thi rd o ra nge

cro ssba nd o f bl a ck ha i rs

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sc u tu m

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a b d o me n

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te rgi te 5 ye l l o w

yel l ow ma r k i ngs rea ch si d e m a rgi n

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Migrant Marsh Fly Helophilus affinis IDENTIFICATION 14–16 mm. A large Helophilus. Face with black

medial stripe; dusting on frons stops abruptly well before ocellar triangle; antennae black. Scutum dull black with grey longitudinal stripes; scutum with yellow hairs. Wing: vein R4+5 sinuous. Hind femur all black or with orange spot below just before tip; about one-third of base of hind tibia yellow. Posterior margin of tergites black; markings on tergite 2 with blunt inner side. Male: eyes widely separated; fore tarsus yellow, at most with black tinge. Female: upper part of fore tarsus brown–yellow or blackish with lower part yellow. SIMILAR SPECIES Like Parhelophilus and Anasimyia species, but third antennal segment dark and face with wide black medial stripe. Like H. trivittatus but face with black instead of yellow medial stripe. Is larger than H. pendulus and with larger dark parts on hind femur and hind tibia. Like H. hybridus but posterior margin of tergites black, instead of with narrow yellow posterior margin, moreover, fore tarsus paler. Much like H. groenlandicus, sharing black posterior margins of

tergites but scutum entirely covered with yellow hairs, fore tarsus paler, dusting on frons not reaching ocellar triangle and markings on tergite 2 with blunt inner side. OCCURRENCE An irregular migrant from the north or east, that usually appears during late summer in coastal regions with abundant flowers. May reproduce in Denmark, but only as a vagrant further south. ECOLOGY Tallherb vegetation with abundant flowers, such as stands of thistles but also in dunes with abundant Grass-of-Parnassus. The way to find this species in region covered by this book is to persistently keep checking every Helophilus in summer. Larval biology unknown, but probably similar to that of other Helophilus.

Black-margined Marsh Fly Helophilus groenlandicus IDENTIFICATION 12–15 mm. A large, relatively dark Helophilus.

Face with wide shiny black medial stripe; dusting on frons extends distinctly, though weakly, across ocellar triangle; antennae dark brown to black. Scutum dull black with grey longitudinal stripes; hairs on scutum largely yellow, but with a crossband of black hairs between wings; scutellum with black hairs. Wing: vein R4+5 sinuous. Hind femur black or with small yellow tip, about one-third of base of hind tibia yellow; fore tarsus black. Posterior margin of tergites widely black; tergite 2 and 3 with relatively narrow, pointed yellow spots, giving species a dark appearance; tergite 2 with pair of wedge-shaped markings, inner sides merging in greydusted spots. Male: eyes widely separated. SIMILAR SPECIES Like Parhelophilus and Anasimyia species, but third antennal segment dark brown to black and face with black medial stripe. Owing to relatively small spots on abdomen, darker than other Helophilus. Only Helophilus with mostly black hairs on posterior part of scutum. In Helophilus most similar to H. affinis, sharing black posterior margin on tergites; however, besides distinctive black hairs on scutum, fore tarsus clearly black, spots on tergite 2

sharp-pointed and frons also lightly dusted across ocellar triangle. OCCURRENCE Northern Scandinavia and to the east, but also very rare in coastal districts of north-west Scotland and the Inner Hebrides. ECOLOGY In Scandinavia known from wetlands, bogs, taiga and tundra, where flower visiting has been observed on several plant species. Larval biology unknown, but likely aquatic.

Yellow-barred Pond Fly Sericomyia silentis IDENTIFICATION 14–18 mm. A large robust yellow-and-black hoverfly. Face yellow with black medial stripe; face slightly protruding downwards; arista with very long hairs. Scutellum black, centre sometimes dark red. Wing: crossvein r-m in about middle of cell dm. Tibiae and tarsi yellow, femora black at base. Tergites 2–4 with pairs of yellow stripes, those on tergites 3 and 4 reaching side margin and sometimes fused to a band; posterior margin tergite 4 yellow; tergite 5 largely yellow. Male: tergite 8 yellow; hind trochanter posteriorly with small tubercle. SIMILAR SPECIES Like S. lappona but that species is smaller and appears darker owing to narrower and whiter markings on abdomen; moreover, S. lappona has tergite 5 black, hind femur entirely orange, scutellum redder and spot at tip of wing more distinct. Could be mistaken for Megasyrphus erraticus but is larger, has darker scutellum, arista with longer hairs, tergite 5 yellow and crossvein r-m located in middle instead of before cell dm. OCCURRENCE Widespread; a very mobile species it seems. ECOLOGY Primarily peatlands such as base-poor fens including

valley mire, and bogs, but also in forest with seepages and small brooks and dune slacks. Often sits near the ground on leaves of bushes such as brambles; visits flowering bushes such as hawthorn and Common heather, and attracted to Devil’s-bit scabious. Often turning up some distance form apparently suitable breeding habitat. Males will hill-top in large numbers. Larva lives in pools, ditches, mud or wet decaying wood.

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White-barred Pond Fly Sericomyia lappona IDENTIFICATION 12–14 mm. A handsome, robust hoverfly with pairs of white–yellow stripes on abdomen. Face yellow with wide black medial stripe; arista with very long hairs. Scutellum red–brown. Wing: with dark spot near tip; crossvein r-m in about middle of cell dm. Hind femur entirely orange. Pairs of stripes on tergites 2–4 narrow, white–yellow, not reaching side margin; tergite 5 black; in female sometimes a melanistic form occurs with abdomen entirely black. SIMILAR SPECIES Quite unmistakable, but could be confused with S. silentis; for differences, see that species. OCCURRENCE Much less widespread and frequent than S. silentis, but found at the same sites. ECOLOGY Open boggy woodland, transition mire, base-poor bogs, moorland. Often sits on flowers in low vegetation, for example, on buttercup and Common tormentil, on the transition from peatland to forest and scrub. Larva lives in peaty pools.

Bumblebee Pond Fly Sericomyia bombiformis IDENTIFICATION 16–20 mm. A very large and very convincing mimic of the Buff-tailed bumblebee. Face extended conspicuously downwards; arista with long hairs. Anterior part of scutum and scutellum with yellow hairs, posterior part scutum with black hairs. Wing: with dark spot in middle; crossvein r-m in about middle of cell dm; cell r1 open. Abdomen with white hairs at base and tip, black hairs between. Male: eyes meeting. SIMILAR SPECIES Both in morphology and behaviour very similar to Buff-tailed bumblebee, Bombus terrestris, but bumblebees have much longer antennae and two pairs of wings. Not resembling S. superbiens owing to very different colouration of body hairs. Could be confused with colour morph plumata of Volucella bombylans but that species with shorter and wider abdomen, yellow hairs on sides but not on anterior half of scutum and cell r1 closed. Like Pocota personata but that species with black hairs on scutellum, tergite 3 instead of tergite 2 with pale hairs, arista bare, face not protruding downwards and flies earlier in the season. OCCURRENCE Northern Europe and low mountains and submontane areas in Central Europe. Has sharply declined over the past decades in Belgium.

Not known from Great Britain. ECOLOGY Meadows in and near wet forest with flushes and brooks. Has a preference for blue and purple flowers such as thistles, Devil’s-bit scabious, Field scabious and knapweed. Also, in behaviour, an effective bumblebee mimic: flies in a similar way and crawls into flowers like a bumblebee. Larva undescribed, but egg-laying has been observed in wet mosses along flushes and brooks. COMMENT Until recently, known under the genus name Arctophila, but genetic studies revealed it is best included in Sericomyia.

Furry Pond Fly Sericomyia superbiens IDENTIFICATION 13–16 mm. An excellent bumblebee mimic, with yellow hairs, that flies very late in the year. Face extended conspicuously downwards; arista with long hairs. Scutum with orange hairs. Wing: with dark spot in middle; crossvein r-m in about middle of cell dm; cell r1 open. Legs black. Abdomen with white–yellow hairs. SIMILAR SPECIES Very different from closely related S. bombiformis by different colour of body hairs. Both Matsumyia berberina and Merodon equestris have colour morphs with yellow hairs, but these species, amongst other differences, lack long hairs on arista and lack dark spot on wing; furthermore, Matsumyia berberina smaller and Merodon equestris with vein R4+5 sinuous and tip of hind femur below with a triangular process on outer side. OCCURRENCE Widespread in forested low mountain ranges in Central Europe; locally fairly common. One of a select group of species that flies only in late summer. ECOLOGY Wet peatlands, often those associated with wet forests containing flushes and springs. Favours blue, purple and yellow flowers, for example Devil’s-bit scabious, knapweed,

Spear thistle and yellow composites. Males often sit on leaves of herbs or bushes in forest edge near flowers. Larva undescribed. COMMENT Confusingly also known under the name Arctophila mussitans, but the name A. superbiens was published first and thus has priority; moreover, genetic studies show Arctophila is best included in Sericomyia.

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Pine Haireye Psilota atra IDENTIFICATION 5–8 mm. A small black shiny hoverfly with short convex abdomen. Face without facial tubercle but with protruding mouth edge; eyes in living specimens reddish; eyes with dense long hairs; third antennal segment about twice as long as wide. Base and anterior margin of wing yellow; false vein absent or only rudimentary. Hind femur swollen, in middle 2–3 times wider than mid femur, tip with pronounced ridge covered with spines; hind coxa with white hairs. Male: lower part of katepisternum with white hairs; genitalia with epandrium elongated, almost 1.5 times longer than wide but must be viewed at correct angle to assess, surstylus not distinctly long and narrow. Female: face with white hairs; posterior anepisternum with white hairs; hair fringe under scutellum entirely white. SIMILAR SPECIES Looks a bit atypical for a hoverfly and could be mistaken for a lance fly Lonchaeidae or a fly of the genus Hydrotaea, but these flies have, for example, very different wing venation. Looks like Pipizella and allies, but abdomen shorter and wider and face with distinct mouth edge.

Like Cheilosia, especially C. impressa, but lacks facial tubercle and orbital strip. Like P. anthracina and P. exilistyla; for differences, see those species. OCCURRENCE All three Psilota are expanding on the North-west European continent. Not known from Great Britain. ECOLOGY In and near mature pine woodland (or mixed forest with mature pines), possibly has a preference for Scots pine. Often found on flowering bushes such as hawthorn, Alder buckthorn and willow. Larva lives in decaying sap of pine trees and possibly other coniferous trees.

Anthracine Haireye Psilota anthracina IDENTIFICATION 5–7 mm. A small blue–black shiny hoverfly with short convex abdomen. Face without facial tubercle but with protruding mouth edge; eyes in living specimens reddish; eyes with dense long hairs. Lower part of katepisternum with white hairs. Base and anterior margin of wing yellow; false vein absent or only rudimentary. Hind femur moderately swollen, in middle about 1.5 times wider than mid femur; hind femur at tip with moderately pronounced ridge covered with spines; hind coxa with white hairs. Hairs on posterior margin of tergite 4 two times longer than hairs on anterior part of tergite. Male: epandrium of genitalia not elongated, about as long as wide but must viewed at correct angle to assess, surstylus not strikingly long and narrow. Female: face with black hairs; posterior anepisternum with black hairs; hair fringe under scutellum black, these hairs shorter than hairs on tergite 3. SIMILAR SPECIES For differences with genera other than Psilota, see P. atra. Identification of males without examining genitalia difficult, but width of hind femur intermediate compared to other two species of Psilota, hind coxa and lower part of katepisternum with white hairs, black in P. exilistyla;

surstylus of genitalia not that long and slender like in P. exilistyla and epandrium not longer than wide like in P. atra. Female differs from P. atra by black hairs on face and posterior anepisternum, and slightly narrower hind femur without pronounced ridge; from P. exilistyla by more swollen hind femur and longer hairs on tergite 3 and posterior margin of tergite 4. OCCURRENCE All three Psilota are expanding on the North-west European continent. ECOLOGY In and near mature broad-leaved forests. Often found on flowering bushes such as hawthorn or white umbellifers. Larva lives under bark of trees in sap runs; has several times been found on oak.

Spindly Haireye Psilota exilistyla IDENTIFICATION 5–8 mm. A small blue–black shiny hoverfly with short convex abdomen. Face without facial tubercle but with protruding mouth edge; eyes in living specimens reddish; eyes with dense long hairs. Base and anterior margin of wing yellow; false vein absent or only rudimentary. Hind femur hardly swollen, at most 1.2 times wider than mid femur, tip with rows of spines but with indistinct ridge. Hairs on posterior margin of tergite 4 not much longer than hairs on remainder of tergite 4. Male: hind coxa and lower part of katepisternum with black hairs; epandrium of genitalia not elongated, about as long as wide but must viewed at correct angle to assess, surstylus very long and slender, inner lobe twice as long as epandrium; outer lobe very thin and usually curved backwards. Female: posterior anepisternum with black hairs; hairs on face, underside of scutellum, hind coxa and lower part katepisternum variable, white to black, but usually black; hairs on tergite 3 shorter than hair fringe under scutellum. SIMILAR SPECIES For differences with genera other than Psilota, see P. atra. Much like P. atra and P. anthracina, but hind femur

less swollen, male with black instead of white hairs on hind coxa and lower part of katepisternum, and genitalia with much longer and narrower surstylus. Female best distinguished from P. atra by narrower hind femur and black hairs on posterior anepisternum, and from P. anthracina by relatively shorter hairs on tergite 3 and posterior margin tergite 4. OCCURRENCE All three Psilota are expanding on the North-west European continent. Not known from Great Britain. ECOLOGY Mixed and coniferous forests, historical parkland. Egg-laying has been observed several times at spruce and fir. Larval biology unknown, but likely lives in coniferous trees such as spruce and fir.

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Onion Roundface Eumerus strigatus IDENTIFICATION 6–9 mm. Typical Eumerus with pairs of greydusted stripes on tergites 2–4. Face flat, not very narrow; third antennal segment black, although sometimes dark orange below. Wing: crossvein r-m after middle of cell dm; vein R4+5 straight or nearly so; pterostigma pale brown. Hind femur strongly swollen and with spines below; base of hind femur without tubercle below and entirely covered in long white hairs. Dust stripes on tergites 2–4 of roughly equal width, not narrowing on inner half. Male: sternite 4 with V-shaped posterior margin, with notch at bottom of V; genitalia: surstylus with distinct hook at tip. Female: vertex, posterior to ocelli, with pale grey dust spots against eye margin; tergite 5 largely with pale hairs. SIMILAR SPECIES See E. flavitarsis for identifying it as an Eumerus. Abdomen black with pairs of grey-dusted spots on tergites 2–4, like in E. amoenus, E. ornatus, E. sogdianus and E. funeralis. For differences with E. amoenus, E. ornatus and E. ruficornis, see those species. Like E. funeralis but base of hind femur below without tubercle and underside entirely covered in long white hairs; for additional characters, see that species. Similar to E. sogdianus; female impossible to identify, male has sternite 4 with V-shaped posterior margin and surstylus of genitalia with distinct hook. OCCURRENCE A widespread species in agricultural fields and grasslands. ECOLOGY Unimproved, mainly dry grasslands, grassy embankments, dry grassy fringe along forest edge, but often most abundant along potato and onion fields. Flies low through vegetation, often sits on the ground. Visits variety of flowers. Larva lives in corms, bulbs and roots, including those of agricultural

crops such as onion and potato, but also in hyacinth, iris, daffodil and Parsnip.

Slender Roundface Eumerus sogdianus IDENTIFICATION 6–9 mm. Fairly slender, typical Eumerus with

pairs of grey-dusted stripes on tergites 2–4. Face flat, not very narrow; third antennal segment black, although sometimes dark orange below. Wing: crossvein r-m after middle of cell dm; vein R4+5 straight or nearly so; pterostigma pale brown. Base of hind femur without tubercle below and entirely covered in long white hairs. Dust stripes on tergites 2–4 of roughly equal width, not narrowing on inner half. Male: sternite 4 with drop-shaped notch on posterior margin; genitalia: surstylus without hook at tip. Female: vertex, posterior to ocelli, with pale grey dust spots along eye margin; tergite 5 largely with pale hairs. SIMILAR SPECIES See E. flavitarsis for identifying it as an Eumerus. For differences with E. amoenus, E. ornatus and E. ruficornis, see those species. Like E. funeralis but on average larger, base of hind femur without tubercle below and entirely covered in long white hairs; for more differences, see that species. Much like E. strigatus but slightly slenderer; females cannot be identified, males can: posterior margin of sternite 4 differently shaped and surstylus lacks hook at tip. OCCURRENCE In region covered by this book a very local and scarce species of the coastal plain, where it may go unnoticed among the much commoner E. strigatus. Not known from Great Britain. ECOLOGY Open habitats, dry grasslands with Wild carrot, and agricultural fields, mainly potato and onion fields. Flies low above the ground and rests on vegetation. Has been reared from agricultural crops such as potato and onion but also Wild carrot.

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i nde nta ti o n i n the m i ddl e, te e th a t si de s

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yel l ow h i nd ma rgi n of terg i te 4

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Lesser Roundface Eumerus funeralis IDENTIFICATION 6–7 mm. A small dark Eumerus. Face flat, not

very narrow; third antennal segment black, although sometimes dark orange below. Tergites 2–4 with pairs of grey-dusted spots. Base of hind femur with tubercle below, in female less distinct and sometimes hardly noticeable; basal half of hind femur below with shiny and bare strip, surrounding hairs shorter than hairs on apical half. Male: sternite 4 with V-shaped posterior margin, with deep notch at bottom of V; genitalia: surstylus without hook at tip. Female: anterior part of side margin of tergite 5 with ridge. SIMILAR SPECIES For differences with E. ornatus, see that species. Like E. amoenus, E. strigatus, E. sogdianus and E. ruficornis, but slightly smaller and base of hind femur below with tubercle, can be very indistinct in female; basal half of hind femur below with shiny and bare strip, surrounding hairs shorter than hairs on apical half, entirely covered with white hairs in other four species; male has posterior margin of sternite 4 and surstylus differently shaped than other Eumerus; female has anterior part of side margin of

tergite 5 with ridge, absent in other Eumerus. OCCURRENCE In area covered by this book a largely anthropophilic species associated with ornamental bulb flowers in gardens and parks. ECOLOGY Mainly semi-natural habitats such as parks and gardens; in the eastern part of the range covered by this book, possibly native to small river valleys with wild daffodil. Flies low and fast, sits low near or on the ground, for example, on stones. Regularly visits flowers. Larva mainly lives in bulbs of, for example, daffodil, hyacinth and tulip.

Viper’s-grass Roundface Eumerus ruficornis IDENTIFICATION 6–8 mm. A rare and very local Eumerus threatened at the European scale; with pairs of grey-dusted stripes on tergites 2–4. Face flat, not very narrow; third antennal segment usually bright orange with dorsal margin dark, but sometimes entirely brown; vertex, posterior to ocelli, without pale grey dust spots along eye margin. Base of hind femur without tubercle below and entirely covered in long white hairs. Male: dust stripes on tergites 2–4 narrow progressively towards inner side; tergite 4 with yellowish band across posterior margin, widest in middle; middle of posterior margin of sternite 4 with indentation, sides in shape of shark teeth; posterior corners of sternite 4 with dense black hairs; genitalia: surstylus not globular and without hook at tip. Female: tergite 5 largely with black hairs. SIMILAR SPECIES Male best distinguished from similar species by yellow posterior margin of tergite 4, but this can be indistinct; also check unique shape of posterior margin of sternite 4 and genitalia. Combination of largely black hairs on tergite 5 and vertex without pale grey dust spots along eye margin identifies female from all similar species. OCCURRENCE Has sharply declined

in Europe following the dramatic loss of its habitat and foodplant. Not known from Great Britain, occurs locally in the south of Belgium. ECOLOGY Unimproved meadows with Viper’s-grass. Flies among low-growing vegetation near Viper’s-grass; settles on taller plants. Larval biology unknown, but there are strong indications that Viper’s-grass is the foodplant.

Daffodil Roundface Eumerus narcissi IDENTIFICATION 6–8 mm. Face flat, not very narrow; third antennal segment deep orange to dark brown; distance from posterior ocelli to posterior margin of head more than twice that to front ocellus. Hind femur strongly swollen, its base without a tubercle. Tergites 2–4 with pairs of grey-dusted spots. Male: sternite 4 wider than long, posterior margin deeply concave; pregenital segments largely covered with black hairs; surstylus not prominent, cone-shaped. Female: vertex with pale grey dust spots along eye margin, adjacent to ocelli; tergite 5 covered with black hairs. SIMILAR SPECIES For differences with E. ornatus and E. ruficollis, see those species. Like E. amoenus, E. funeralis, E. sogdianus and E. strigatus, but ocelli more forward on head (see key); male distinguished from these by dark hairs on pregenital segments and different shape of sternite 4 and genitalia; female by black hairs on tergite 5. OCCURRENCE In the region, very recently discovered on the Scillies and in Cornwall, otherwise known from Southern Europe and North America, where introduced. ECOLOGY Flies fast and low through ground

vegetation. The species is associated with Narcissus and its distribution in Southern Europe and observations in cultivated fields suggest it may specifically prefer N. tazzeta. In North America, it apparently also uses other foodplants such as onions and Hippeastrum.

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o ra nge -re d abdome n gra d ua l l y n a rro wi ng

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Orange-horned Roundface Eumerus amoenus IDENTIFICATION 7–10 mm. A slender shiny blue species. Face

flat, not very narrow; third antennal segment usually extensively brightly orange at base; distance between front and posterior ocelli larger than distance from posterior ocelli to eye corners. Hind femur strongly swollen, base without tubercle. Wing: crossvein r-m after middle of cell dm; vein R4+5 straight or nearly so; pterostigma pale brown. Tergites 2–4 with pairs of grey-dusted spots. Male: sternite 4 longer than wide, with deeply concave posterior margin, with central longitudinal dusted groove not reaching front margin; genitalia: tip of surstylus evenly wide, surstylus below with large notch. Female: vertex, posterior to ocelli, with pale grey dust spots along eye margin; tergite 5 with predominantly pale pile. SIMILAR SPECIES See E. flavitarsis for identification as an Eumerus. For differences with E. narcissi, E. ornatus and E. ruficornis, see those species. Like E. funeralis, E. sogdianus and E. strigatus, but third antennal segment extensively brightly orange at base, slenderer, with narrower

abdomen, shorter body hairs and scutum sheen less olive but more blueish; male also easily recognised by shape of sternite 4 being longer than wide, instead of wider than long and typical shape of posterior margin, and by shape of surstylus, including notch below, and evenly wide tip. OCCURRENCE In region covered by this book, a probable recent record from Britain. Otherwise, widespread in Southern Europe, occurring up to the northern half of France. ECOLOGY Prefers open forest, wood pasture and semi-open landscapes with hedges and patches of forest. It flies among low-growing vegetation up to 1 metre above the ground, often in partially shaded conditions. The species has been reared from various crops and plants including potato and onion.

Woodland Roundface Eumerus ornatus IDENTIFICATION 8–10 mm. A rather large, slender shiny black

Eumerus with distinctively large head and eyes. Face very narrow, flat, with thick silver–white dusting; third antennal segment mostly or entirely orange; ocellar triangle placed far forward on head: distance between front and posterior ocelli smaller than distance from posterior ocelli to eye corners. Wing: crossvein r-m after middle of cell dm; vein R4+5 straight or nearly so; pterostigma dark brown. Hind femur moderately swollen. Tergites 2–4 with pairs of grey-dusted spots; abdomen gradually narrowing to tip, sides not parallel. Male: eyes meeting over a long distance, longer than length of ocellar triangle; cerci of genitalia strikingly large, rounded and orange–yellow, also visible in the field. Female: face shiny, hardly dusted. SIMILAR SPECIES For identification as an Eumerus, see E. flavitarsis. Like other Eumerus with pairs of grey-dusted spots on abdomen, but hind femur less swollen and ocellar triangle placed remarkably far forward, making distance between front and posterior ocelli smaller than distance from posterior ocelli to eye corners, distance larger in all similar species; pterostigma darker; in male eyes meeting over a length longer

than length of ocellar triangle, and cerci strikingly large and orange. OCCURRENCE Widespread but localised in broad-leaved forests in the range covered by this book. ECOLOGY At the forest edge or on sunlit places in old broad-leaved forests with rich undergrowth. Often sits on low vegetation or on the ground, males hold territories in the forest edge. Larval biology unknown.

Silver-footed Roundface Eumerus flavitarsis IDENTIFICATION 6–8 mm. A slender shiny blue–black Eumerus.

Face very narrow, flat, with thick silver–white dusting; third antennal segment mostly or entirely orange. Wing: crossvein r-m after middle of cell dm; vein R4+5 straight or nearly so. Tergites 3 and 4 with pairs of grey-dusted oblique spots, tergite 2 without such spots but with pair of small obliquely placed yellow translucent oval spots; abdomen between tergite 2 and 3 slightly constricted. Male: hind tarsus widened and with dense, strongly reflective silvery–white hairs on upper side. SIMILAR SPECIES Identified as an Eumerus species by abdomen with pairs of grey-dusted spots, crossvein r-m after middle of cell dm and vein R4+5 not sinuous. Easily distinguished from other North-west European Eumerus: the only one with a pair of yellow spots on tergite 2 and the male unique in possessing striking white hairs on hind tarsus. OCCURRENCE A rather local species in the south of the range covered by this book, easily overlooked. Not known from Great Britain. ECOLOGY Along forest tracks, at clearings and glades in old mixed and broad-leaved forests on

base-poor soil, often near brooks. Males in courtship flight fly quickly back and forth in small sunlit places in forest, creating a stroboscopic effect with their silvery legs. Males often settle on leaves at these places. Visits low flowers, often those of Common tormentil. Larval biology unknown.

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♂

a b d o me n

e ye s a l m o st m e e t i n a si ngl e po i nt

e nti re l y bl a ck

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f ore tarsus

head

e ye ha i re d

♀

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a b d o me n

f o re ta rsu s

bl a ck bri stl e s

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e ye s m e e t

o c e l l a r tri a n g l e

e qui l a te ra l tri a ngl e

♂

e ye ba re

head

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a b d o me n

♂ fore a nd mi d ta rsi p a rtl y ora n ge

♂

s lightly s malle r tha n two s pe ci es a b o ve

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eyes a l m o st m eet

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head

o c e l l a r tri a n g l e

i so sce l e s tri a ngl e

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Goatsbeard Roundface Eumerus tricolor IDENTIFICATION 8–11 mm. A large Eumerus with predominantly red abdomen. Face flat, almost undusted; eyes with sparse but distinct hairs; third antennal segment dark and outer side at top with a depression. Fore and mid tarsi brown–black; tarsomeres of fore tarsus without black bristle in tip corners. In male tergites 2 and 3, and in female tergites 2–4, predominantly red; tergites 2–4 with pairs of grey-dusted spots. Male: eyes not meeting, but almost do at a single point. SIMILAR SPECIES See E. flavitarsis for identification as an Eumerus species. Resembles E. tarsalis and E. sabulonum owing to red abdomen but distinguished by eyes with hairs and fore and mid tarsi brown– black; moreover, E. sabulonum smaller and male E. tarsalis has eyes meeting over some distance and black bristles on tip of tarsomere corners of fore leg. OCCURRENCE A southern species that has its northern range limit in Belgium and the Netherlands. Not known from Great Britain. ECOLOGY Dry, warm unimproved flower-rich meadows, roadsides, along railways and

dry unimproved grassy fringes along forest. Usually found in the vicinity of Yellow salsify. Flies low above the ground and often sits on ground. Larva has been found in salsify; egg-laying has been observed on Goatsbeard.

Peg-footed Roundface Eumerus tarsalis IDENTIFICATION 9–11 mm. A large Eumerus with predominantly red abdomen. Face flat, almost undusted; eyes almost bare; third antennal segment dark and outer side at top with a depression. Fore and mid tarsi with basal tarsomere orange, tarsomeres 2 and 3 orange with black base and tarsomeres 4 and 5 black; tarsomeres 1–4 of fore tarsus with black bristle in tips of corners. In male tergites 2 and 3, in female tergites 2–4, predominantly red; tergites 2–4 with pairs of grey-dusted spots. Male: eyes meeting over some distance. Female: ocelli in an equilateral triangle, distances between the three ocelli approximately equal. SIMILAR SPECIES See E. flavitarsis for identification as an Eumerus species. Like E. tricolor but eyes (almost) bare, fore and mid tarsi partly pale and in male eyes meeting over some distance. Much like E. sabulonum but larger, with a black bristle on tip of every corner of tarsomeres 1–4 of fore tarsus, in male eyes meeting over some distance (somewhat variable) and in female ocelli in an equilateral instead of isosceles triangle, although difference subtle. OCCURRENCE Very localised populations or stragglers, possibly of imported specimens, were seen in Belgium and the Netherlands

some time ago; currently not present in the range covered by this book. Not known from Great Britain. ECOLOGY Unimproved grasslands, dry forest glades, dry streambeds, often near forests. Flies low and fast, often sits on the ground on stones. Larval biology unknown.

Sheep’s-bit Roundface Eumerus sabulonum IDENTIFICATION 7–9 mm. A fairly small Eumerus with

predominantly red abdomen. Face flat, undusted; eyes bare; third antennal segment dark and outer side at top with a depression. Fore and mid tarsi with basal tarsomere orange, tarsomeres 2 and 3 orange with black base and tarsomeres 4 and 5 black; tarsomeres of fore tarsus without black bristle in tips of corners. In male tergites 2 and 3, in female tergites 2–4, predominantly red; tergites 2–4 with pairs of grey-dusted spots, those on tergite 2 widest. Male: eyes not meeting, but almost do at a single point. Female: ocelli in an isosceles triangle, distance from posterior ocelli to front ocellus shorter than distance between posterior ocelli. SIMILAR SPECIES Differs from Paragus species by larger size, black face and crossvein r-m after middle of cell dm. In Eumerus, shares predominantly red abdomen with E. tricolor and E. tarsalis; E. tricolor larger, has hairs on eyes and fore and mid tarsi entirely dark; for differences with E. tarsalis, see that species. OCCURRENCE On the south and west coast of Great Britain and in coastal areas of Denmark, Germany and the Netherlands,

extinct in Belgium. Seems to have disappeared from its few inland locations over the past decades, possibly following severe droughts. ECOLOGY Scarcely vegetated dunes, open sandy spots in forested dunes, rocky cliffs, coastal heathlands, with stable populations of Sheep’s-bit. Flies fast and low, often sits on the ground. Visits assorted low flowers. Easily missed due to small size and similarity to blood bees, Sphecodes. Mainly active in hot and sunny weather. Usually found near the host plant, Sheep’s-bit.

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a b d o me n

w i de duste d stri pe s

grey dusted stri p es wi tho ut e x tra pro ce sse s

♂

hind leg

♀

♂

♂

a b d o me n

hind leg

sm a l l duste d stri pe s 3 e x tra pro ce sse s i nde nta ti o n

s pots a b sent or indi sti nct

♀

te rg i te 4

♀

a b d o me n

♂ sm a l l o ra nge spo ts

w i tho ut spo ts

♂

wi tho ut spo ts

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wi tho ut extra pro ce sse s

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Tapered Bulb Fly Merodon moenium IDENTIFICATION 10–13 mm. Medium-sized bee-mimicking

Merodon. Face flat, with fine white dusting; antennae red–brown; eyes with dense hairs. Scutum with four dull grey longitudinal stripes. Wing: vein R4+5 sinuous; cell r1 open. Tip of hind femur below with a triangular process. Abdomen decreasing in width, conical; tergite 2 with orange spots, tergites 3 and 4 with pairs of oblique grey dust stripes. Male: hind femur below in middle and hind tibia below near tip without pointed process; hind trochanter without spiny process. SIMILAR SPECIES Recognised as a Merodon by combination of tip of hind femur below with a triangular process, vein R4+5 sinuous and cell r1 open. Like M. ruficornis but male lacks spiny processes on hind trochanter, middle part of hind femur and tip of hind tibia; female differs by having grey-dusted longitudinal stripes on scutum. Unlike M. rufus, owing to its grey dust stripes on scutum and tergites 3 and 4. OCCURRENCE The most northern population of this species in Europe is in Bornholm (Denmark), populations in Belgium and the Netherlands have

perished, but recently found again in Belgium and Luxembourg. Not known from Great Britain. June–August. ECOLOGY Grasslands in the vicinity of forest, forest glades, often near streams. Flies low and fast among herbs and sits in open spots on the ground. Makes a loud buzzing sound in flight. Larval biology unknown, but probably lives in several bulbous plant species, including Grape hyacinth. COMMENT Until recently, mainly known under the name M. avidus, but M. avidus appeared to be a species complex and the species in the complex occurring in region covered by this book is M. moenium, M. avidus itself mainly occurring in the Mediterranean Basin.

Spine-legged Bulb Fly Merodon ruficornis IDENTIFICATION 10–13 mm. A bee-mimicking Merodon. Face flat, finely dusted white; antennae dark brown; eyes with dense hairs. Wing: vein R4+5 sinuous; cell r1 open. Tip of hind femur below with a triangular process on outer side. Tergite 2 with orange side spots. Male: hind trochanter, hind femur below in middle and hind tibia below near tip with pointed process; tergites 2–4 with pairs of grey-dusted stripes that may be absent on tergites 3 and 4. Female: scutum without longitudinal dust stripes; tergites 2–4 with pairs of small grey-dusted stripes; tergite 4 usually with transverse indentation. SIMILAR SPECIES Recognised as a Merodon by combination of tip of hind femur below with a triangular process, vein R4+5 sinuous and cell r1 open. Male is the only Merodon in this book having pointed processes on hind femur below in middle and hind tibia below near tip. Female like M. moenium but scutum without longitudinal stripes and tergite 4 with indentation; like M. aureus but larger and tergite 2 with orange spots. OCCURRENCE Very local in submontane forests, often near rivers. Several old records from Belgium. Not known from Great Britain. ECOLOGY Open flower-rich areas in

broad-leaved forests. Flies low above and among vegetation and suns on leaves of low vegetation. Larval biology unknown. COMMENT Merodon armipes occurs as close as central Germany and could appear in the region. Male differs from M. ruficornis by much longer process on hind trochanter and with a spur on tip of hind tibia. Female differs by possessing a backward-facing posterior process on sternite 4.

Uniform Bulb Fly Merodon rufus IDENTIFICATION 10–12 mm. A small, rather slender Merodon.

Face flat, mouth edge slightly protruding; third antennal segment orange–brown; eyes with hairs. Wing: vein R4+5 sinuous; cell r1 open. Legs black except base of tibiae; tip of hind femur below with a triangular process on outer side. Tergite 2 with small indistinct orange side spots, tergites 3 and 4 without markings. Male: hind trochanter without process; hind tibia without process or spur at tip; hind femur curved. Female: scutum without longitudinal stripes, hairs on abdomen short and in middle partly black, bronze ground colour shines through. SIMILAR SPECIES Recognised as a Merodon by combination of tip of hind femur below with a triangular process, vein R4+5 sinuous and cell r1 open. Male like colour morph flavicans of M. equestris but smaller, body hairs less dense and tibiae with yellow base; male like M. aureus but larger, body with less dense hairs and hind trochanter without pointed process; male like M. ruficornis but without extra processes on hind leg; male like M. moenium but tergites 3 and 4 without pairs of dust stripes. Female differs from

M. aureus, M. ruficornis and M. moenium by abdomen lacking pairs of grey-dusted spots. OCCURRENCE A widespread but very local species in Central European submontane and montane forests. Not known from Great Britain. ECOLOGY In region covered by this book on dry unimproved grasslands and warm southexposed forests on well-drained soil with open canopy; restricted to chalk. Flies low and quickly over sparse vegetation and often sits on the ground. Visits flowers of St Bernard’s lily. Larva lives in bulbs of St Bernard’s lily.

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a b d o me n

3 pa i rs o f duste d stri pe s

e ntire ly cove re d in golde n- ye llow hairs

hi nd trocha nte r wi th spi ne

♂

♂

hind leg

equestris

♂

hind leg

p rocess

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transversalis

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validus

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nobilis

♂

flavicans

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bulborum

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Golden Bulb Fly Merodon aureus IDENTIFICATION 7–10 mm. A tiny Merodon. Face fairly flat, mouth edge slightly protruding; antennae attached very low on the head; third antennal segment red–brown. Wing: vein R4+5 sinuous; cell r1 open. Legs black except base of tibiae; tip of hind femur below with a triangular process on outer side. Ground colour of abdomen bronze, without pairs of spots. Male: entirely covered in golden-yellow hairs; hind trochanter with spine. Female: scutum with dense golden-yellow hairs, contrasting with darker and much less dense hairs on abdomen; abdomen grey–black with pairs of grey-dusted stripes on tergites 2-4. SIMILAR SPECIES Male could maybe be mistaken for Cheilosia chrysocoma but much smaller and recognised as a Merodon by triangular process at tip of hind femur. Female smaller than other Merodon and with different pattern on abdomen: besides tergites 3 and 4, also tergite 2 with pair of grey-dusted stripes, but orange side spots on tergite 2 absent. OCCURRENCE Montane and submontane areas in Central Europe, some records in southern Belgium. Not known from Great Britain. ECOLOGY Flower-rich unimproved meadows, grassy forest clearings and roadsides. Flies very fast and low through vegetation and rests on flowers or on the ground. Visits assorted flowers both in low grassland and tall-herb grassland with umbellifers. Larval biology unknown. Larval foodplant unknown, but suggested candidates are Star-of-Bethlehem, Grape hyacinth or crocus. COMMENT Also known under the name M. aeneus; however, the name aureus was published first and should have priority, although some uncertainty exists surrounding the identity of the type material.

Narcissus Bulb Fly Merodon equestris IDENTIFICATION 12–14 mm. A large bumblebee-mimicking

Merodon. Face slightly concave, mouth edge and base of antennae slightly protruding; antennae black; eyes with hairs. Six genetically determined colour morphs occur (see illustration); morphs equestris and flavicans occur in both sexes, nobilis and validus almost exclusively in females, bulborum and transversalis most often in males. Wing: crossvein r-m just after middle of cell dm; vein R4+5 sinuous; cell r1 open. Legs black. Tip of hind femur below with a triangular process on outer side. Male: hind trochanter with small tubercle and inner side of tip of hind tibia with long curled spine. SIMILAR SPECIES Can be confused with other bumblebee-mimicking hoverflies but only species with tip of hind femur below with a triangular process on outer side. Male flavicans could be confused with M. aureus, but much bigger, legs entirely black and hind tibia with spine at tip. OCCURRENCE Possibly a non-native species in North-west Europe that arrived with imported flower bulbs from southern Europe. Colour morphs bulborum, equestris and flavicans common, validus less common and nobilis and transversalis rare. Regional and possibly ecological differences occur in the prevalence of the different morphs. ECOLOGY Especially in gardens and parks with bulbous plants, rarer in natural habitats. Flies low and noisily (males) above vegetation and visits many flowers. Males seem to hold territories. Larva lives in several bulbous plants, often in daffodils.

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bombylans

head

a ri sta w i th v e ry l o ng ha i rs

da rk spo t

ce ll r 1 clos e d

stro ngl y pro trudi ng do w nwa rds

♂

♂

plumata

haemorrhoidalis

ti p o f a bdo m e n o ra nge

ti p of a b do m en wh i te

♂

scutu m sh i ny

a h uge fl y!

♂

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head

a b d o me n

re d o ra nge ye l l o w

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Bumblebee Plumehorn Volucella bombylans IDENTIFICATION 11–17 mm. The only Volucella in region covered

by this book mimicking a bumblebee. Face strongly protruding downwards; arista with very long hairs. Bristles on posterior margin of scutellum absent. Wing: with dark spot in middle; crossvein r-m before middle of cell dm; cell r1 closed. Abdomen relatively short and wide. Occurs in three genetically determined colour morphs: bombylans has black haired body but with hairs on tip of abdomen orange; in plumata, body with black and yellow hairs, with tip of abdomen with yellow–white hairs; morph haemorrhoidalis like plumata but tip of abdomen with orange hairs. SIMILAR SPECIES Can be confused with other bumblebee mimicking species, mainly with Sericomyia owing to similar elongated face and long hairs on arista but, for example, has shorter and wider abdomen and crossvein r-m located before middle of cell dm. Vein R4+5 not sinuous like in Eristalis and Merodon. OCCURRENCE Widespread and common throughout the whole range covered by this book. Usually colour morphs bombylans and plumata are equally common and haemorrhoidalis is scarce, but ratios can differ among regions. Elsewhere, other colour morphs occur. ECOLOGY Broad-leaved forests, forest edges, near scrub and bushes, sheltered edges of flowery meadows but also in gardens. Visits assorted large flowers. Males hold territories from low perches at the forest edge and will hover at about 1 metre above the ground, usually near a bush. Females lay eggs in bumblebee nests; larva lives in the nest, on waste and dead bumblebee larvae.

Hornet Plumehorn Volucella zonaria IDENTIFICATION 18–22 mm. A very large hoverfly; size and reddish to yellow bands on abdomen make it reminiscent of a hornet, especially when in flight. Face strongly protruding downwards; arista with very long hairs. Scutum shiny and red–brown (female) or black with red–brown sides and area before scutellum (male). Wing: crossvein r-m before middle of cell dm; cell r1 closed. Tergite 2 with pair of large red markings and wide black posterior margin; tergite 3 with orange band, posterior margin can have an incision in middle, especially in male; tergite 4 yellow; sternite 2 black. SIMILAR SPECIES This striking and huge hoverfly can be confused only with V. inanis or maybe Milesia crabroniformis; for differences with the latter, see that species. Like V. inanis but larger, markings on tergite 2 and band on tergite 3 not yellow but red and orange, respectively, scutum shiny instead of dull, tergite 2 with on average a wider black posterior margin, tergite 4 without black posterior margin and sternite 2 black instead of yellow. OCCURRENCE Has strongly increased and shifted northwards over North-west Europe. Because V. zonaria is so large and striking and frequently visits gardens, the species is overrepresented relative to other species on distribution maps. ECOLOGY Especially suburban areas, half-open habitats; often in gardens. Visits many flowers, including those of thistles, Hemp-agrimony, ivy and Summer lilac. Males hover several metres above the ground in sheltered places. Partly migratory. Larva lives in nests of hornets and other Vespulawasps feeding on waste and dead wasp larvae.

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a b d o me n

♂ s cutu m d ul l

a l l ba nds ye l l o w

♂

♀

head

a b d o me n

i v o ry w hi te

♂

a ri sta w i th v e ry l o ng ha i rs

♂

♀

♂

head

a b d o me n

o ra nge -ye l l o w

♂

head

f a ce stro ngl y pro trudi ng do w nwa rds

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Wasp Plumehorn Volucella inanis IDENTIFICATION 14–16 mm. A medium-sized Volucella

with yellow bands on abdomen. Face strongly protruding downwards; arista with very long hairs. Scutum dull black with wide orange–yellow sides and yellow area before scutellum. Wing: crossvein r-m before middle of cell dm; cell r1 closed. Tergites 2–4 with bright-yellow bands, one on tergite 2 usually with black medial line, creating a pair of spots; sternite 2 yellow. SIMILAR SPECIES Mainly can be confused with V. zonaria; for differences, see that species. Vaguely resembling Sericomyia silentis but yellow markings on abdomen wider, wing with spot at tip, cell r1 closed and crossvein r-m before middle of cell dm. OCCURRENCE This species is expanding northwards in recent years both in Great Britain and on the continent. ECOLOGY Near forests, often on chalk, in flower-rich tall-herb grasslands in mosaic landscapes with woodland, urban settlements and open habitats. Frequently visits brambles, Hemp-agrimony and white umbellifers. Larva is carnivorous and lives in nests of hornets

and other Vespula-wasps where its preys on the larvae of the wasps.

Pied Plumehorn Volucella pellucens IDENTIFICATION 13–18 mm. A very large hoverfly with a distinctive pattern on abdomen. Face protruding downwards; arista with very long hairs. Scutum black with dark-yellow to dark-brown sides. Wing: with large dark spot in middle and a small one near tip; wing base orange–yellow; crossvein r-m before middle of cell dm; cell r1 closed. Tergite 2 ivory white, sometimes with black longitudinal incision in middle, remainder of abdomen black. Male: eyes with hairs; scutum and scutellum with erect black hairs. Female: eyes bare; scutum with adpressed hairs, anterior part predominantly with golden-yellow hairs, posterior part predominantly with black hairs; hairs on scutellum adpressed and black. SIMILAR SPECIES Vaguely resembling Leucozona but, amongst other characters, much larger and more robust, with elongated face, cell r1 closed and arista with much longer hairs. Can be confused only with V. inflata but slightly larger; pale marking on tergite 2 whiter, face less protruding downwards, sides of scutum on average darker yellow, scutellum and at least posterior half of scutum with black hairs, in female eyes bare and distance between eyes smaller, and in male eyes meeting

over a longer distance. OCCURRENCE A widespread and rather long-lived common species that flies from late spring to early autumn. ECOLOGY In broad-leaved forests, parks, gardens. Males often hover in loose swarms in forest clearings in partial shade at several metres above the ground. Sunbathes on leaves of trees and bushes and visits flowers such as those of limes, brambles, hogweed, Summer lilac and Devil’s-bit scabious. Females lay eggs in nests of Vespula-wasps; larva lives at the bottom of the nests, eating waste and dead wasp larvae.

Orange-belted Plumehorn Volucella inflata IDENTIFICATION 13–16 mm. A relatively small Volucella. Face

strongly protruding downwards; arista with very long hairs; eyes with hairs in both male and female; sides of scutum orange– red to orange–yellow; scutum and scutellum with long erect golden-yellow hairs. Wing: with a large dark spot in middle and a small one near tip; wing base orange–yellow; crossvein r-m before middle of cell dm; cell r1 closed. Tergite 2 largely orange– yellow with black medial stripe, remainder of abdomen black. SIMILAR SPECIES Can be confused only with V. pellucens, but stands out in the field by smaller size and orange–yellow instead of ivory-white tergite 2. Other differences include face protruding further downwards, paler sides of scutum, scutum and scutellum with yellow instead of partly black hairs, eyes in male meeting over a shorter distance, and in female eyes with hairs and frons between eyes wider. OCCURRENCE Increasing over the past decades both on the continent and in Great Britain. ECOLOGY Broad-leaved woodlands with mature trees, especially with oak. Males hover several metres above the ground. Often

visits flowers of bushes including hawthorn, Raspberry, Wild privet, Common dogwood and brambles. The only Volucella in the region in which the larva does not live in nests of bumblebees or eusocial wasps but in sap runs or insect tunnels in broad-leaved trees.

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a b d o me n

♂

♂

head

unm i sta ka b l e

♀

a b d o me n

♂

w i ngti p da rke ne d

♂

♂

head

♂

head

unm i sta k a bl e, the bi gge st ho v e rf l y i n E uro pe

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Pine Hoverfly Blera fallax IDENTIFICATION 10–12 mm. A medium-sized hoverfly with a unique colour pattern: black with red-tipped abdomen. Face yellow; antennae shorter than head; frons conically protruding forwards. In male tergite 1 and 2 black, in female tergites up to halfway of tergite 4 black, remainder of abdomen red. SIMILAR SPECIES Unmistakable. Psarus abdominalis has abdomen predominantly red too, but that species has longer antennae and black face, amongst other differences. OCCURRENCE Locally common in mature spruce plantations in the Ardennes and Eiffel region; otherwise, local and rare in montane and submontane coniferous forests of Central Europe. Very localised and endangered in Scotland where restricted to native Scots pine woodland at just a few sites. The Scottish population can hopefully benefit from an ongoing species action plan. ECOLOGY Mature coniferous forests with overmature and damaged trees, but sometimes also mixed forest or broad-leaved forest. Males sit on or near stumps and trunks of dead trees. Suns on leaves. Often

visits flowers of flowering bushes and buttercup. Larva lives in cavities in pine and spruce.

Jewel Wood Fly Caliprobola speciosa IDENTIFICATION 13–17 mm. Beautiful large species with

elongated shiny golden-green abdomen. Face yellow, sides of mouth edge black; frons and antennae orange; frons conically protruding forwards. Scutum shiny green–black with indistinct grey-dusted longitudinal stripes. Wing: with wide yellow anterior margin and with dark spot in apical half. Basal three-quarters of femora black, remainder of legs orange. Midline of abdomen and posterior margin of tergites 2–4 with adpressed dense goldenyellow hairs. SIMILAR SPECIES Slightly resembling Ferdinandea species, but much larger and more elongated, scutum without black bristles and wing with wide yellow anterior margin but without dark spots at crossveins. OCCURRENCE Widespread in the southern and eastern part of the range covered by this book. In the past decades, has expanded its continental range, but remains rare and restricted to two small areas in Great Britain. ECOLOGY Mature broad-leaved woodlands with overmature trees, often with beech or oak. Males sit on and fly around trunk bases of old oaks and beech, especially where there is dappled sunlight and exposed heart rot. Visits flowering bushes such as

hawthorn and umbellifers. Larva has been found in decaying roots of beech stumps.

Hornet Giant Milesia crabroniformis IDENTIFICATION 18–27 mm. An enormous hoverfly, mimicking European hornet. Face yellow; antennae predominantly orange; arista with short hairs. Scutum black with angular yellow markings on anterior half and a red–brown marking on posterior half; scutellum red–brown. Abdomen elongated; tergites with pattern of diffuse yellow and orange markings. Femora and ring on hind tibia orange–red, remainder of legs yellowish; hind femur below at tip with protrusion. Wing: cell r1 closed; crossvein r-m well after the middle of cell dm; anterior part of wing with yellow veins, posterior part and tip slightly dark. SIMILAR SPECIES Quite unmistakable. Vaguely resembling Volucella zonaria, the only other hornet-mimicking hoverfly covered in this book, but abdomen much more elongated, colour distribution on abdomen different, arista with much shorter hairs, crossvein r-m well after middle of cell dm, etc. OCCURRENCE The Mediterranean Basin up to northern France. Some uncertain, very old records from southern Belgium. Not known from Great Britain. ECOLOGY Broad-leaved forest with overmature trees. Behaves like a European hornet, with similar

flight and makes similar buzzing sound. Visits tall-herb flowers and flowering bushes, such as umbellifers, Dwarf elder and in autumn ivy. Larva undescribed, but egg-laying has been observed near rot holes of overmature oak and plane.

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♂

a b d o me n

head

ba nds a nd spo ts

♂ i nverted V ye l l o w ba nds uni nte rrupte d

w i th l o ng ha i rs

th o ra x l a te ra l

♀ ♂

a b d o me n

eye wi th b a nds a n d spo ts ye l l o w ba nd i nte rrupte d

w i th sho rt ha i rs

th o ra x l a te ra l

♀

♂

a b d o me n

yel l ow sp o t u ni nterru pted s pots continue ov er the pos talar cal l i

yel l ow sp o t tri a ngul a r

use s bl a ck f o re l e gs to i m i ta te l o ng a nte nna e o f a wa sp

♂

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Hairy Hornet Fly Spilomyia manicata IDENTIFICATION 11–17 mm. A splendid wasp-mimicking species with banded eyes. Face yellow, flat; antennae orange–brown, shorter than head; eyes green with red–brown spots and bands. Scutum with fairly long hairs; yellow markings including an inverted V-shaped mark before scutellum; sides of thorax with five yellow marks. Underside of hind femur at tip with tubercle; over half of fore tibia black, only base yellow; fore tarsus entirely black. Yellow anterior band on tergites 3 and 4 hardly interrupted. Male: yellow posterior band on tergite 4 with undulating anterior margin. SIMILAR SPECIES Immediately recognised as a Spilomyia by combination of banded eyes, yellow bands on abdomen, yellow inverted V-shaped marking on scutum and hind femur below with tubercle at tip. Like S. saltuum but scutum with long hairs, fore tarsus entirely black, fore tibia more extensively black, yellow anterior bands on tergites 3 and 4 hardly interrupted in middle, and male with undulating anterior margin of posterior band of tergite 4. OCCURRENCE In the range covered by this book, widely

scattered records (Belgium, the Netherlands, northern France, Denmark) but records are few and mostly old, which suggests it does not (anymore) reproduce in the area covered by this guide. Not known from Great Britain. ECOLOGY Broad-leaved forests with overmature trees with cavities. Behaves like a wasp, flying very fast through the vegetation. Visits white umbellifers. Larva lives in cavities of broad-leaved trees.

Fivespot Hornet Fly Spilomyia saltuum IDENTIFICATION 11–15 mm. A handsome wasp-mimicking species with banded eyes. Face yellow, flat; antennae orange–brown, shorter than head; eyes green with red–brown spots and bands. Scutum with short hairs and inverted V-shaped mark before scutellum; sides of thorax with five yellow marks. Underside of hind femur at tip with tubercle; fore tarsus with at least tarsomere 4 and 5 yellow; fore tibia yellow, at most extreme tip black. Anterior yellow band on tergites 3 and 4 interrupted in middle. Male: yellow posterior band on tergite 4 with straight anterior margin. SIMILAR SPECIES Immediately recognised as a Spilomyia by combination of banded eyes, yellow bands on abdomen, yellow inverted V-shaped marking on scutum and hind femur below with tubercle at tip. Like S. manicata; for differences, see that species. OCCURRENCE The northern limit of its range is in Central France; some scattered records more northerly (the Netherlands) may be stragglers or imports with wood trade. Not known from Great Britain. ECOLOGY Broad-leaved woodland with overmature trees with rot holes. Flies very fast through vegetation or visits flowers of, for example, umbellifers. Males hover briefly,

up to several metres above the ground or sit on sunlit trunks of old trees from where they chase other insects. Larval biology unknown, but other Spilomyia live in rot holes.

Wasp Falsehorn Temnostoma vespiforme IDENTIFICATION 14–18 mm. A convincing wasp-mimicking species. Face without facial tubercle; face with golden-yellow dusting and shiny black medial stripe; antennae orange. Several parts of scutum with yellow dusted marks: postpronotum, margin before transverse suture with an uninterrupted stripe, triangular spot before scutellum and posterior corners of scutum with wedge-shaped spots that continue over postalar calli. Wing: slightly dark. Mid and hind tibiae and tarsi yellow, fore tibia and tarsus predominantly black. Abdomen elongated, oval, with wide yellow bands halfway and just before posterior margin of tergites, bands connected alongside margin and sometimes also in middle; sternites 3 and 4 dusted on all sides. SIMILAR SPECIES Could be mistaken for a Spilomyia, but eyes without bands and spots. Gives a more yellow impression compared with T. bombylans owing to wide double yellow bands on tergites; furthermore, larger, wing less dark, scutum with more yellow markings and abdomen more oval. Mainly like T. meridionale, T. sericomyiaeforme and T. apiforme, for differences with first two, see those species;

differs from T. apiforme by yellower markings on abdomen and by yellow dusted postalar calli and posterior corners of scutum. OCCURRENCE Has increased over the past decades in Belgium and the Netherlands. Not known from Great Britain. ECOLOGY Wet broad-leaved forests and historical parkland with decaying wood, especially abundant in alluvial forests. Visits flowers, often of bushes, buttercups or white umbellifers. Males fly fast along forest edges, near flowering bushes and sit on leaves waiting for females. Uses black fore legs to imitate long antennae of a wasp by holding and waving them along the head. Larva lives in decaying wood.

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♂ ♀

a b d o me n

♀

a b d o me n

♀

a b d o me n

yel l o w sp o t i nterru pted pos talar callus bla ck

yel l ow sp o t rounde d

♂

hind corne rs an d pos talar calli black

o ra n ge

w hi te -ye l l o w ba nds

b a nds som eti me s more yel l o w

♂

o ne w i de ba nd pe r te rgi te o nl y

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Moon Falsehorn Temnostoma meridionale IDENTIFICATION 14–18 mm. A convincing wasp-mimicking species. Face without facial tubercle, with golden-yellow dusting and shiny black medial stripe; antennae orange. Postpronotum dusted yellow; margin before transverse suture with yellow dusted stripe, interrupted in middle; scutum just before scutellum with semicircular yellow dusted spot; posterior corners of scutum with wedge-shaped yellow spots not reaching postalar calli. Wing: slightly dark. Mid and hind tibiae and tarsi yellow, fore tibia and tarsus largely black. Abdomen with wide yellow bands. SIMILAR SPECIES Could be mistaken for a Spilomyia, but eyes without bands and spots. For differences with T. apiforme, see that species. Much like T. vespiforme and T. sericomyiaeforme, but yellow stripe before transverse suture interrupted, posterior corners of scutum with wedge-shaped yellow spots not reaching postalar calli and scutum just before scutellum with semicircular instead of triangular yellow dusted spot; moreover, tergites with two (connected) bands, versus single bands in T. sericomyiaeforme.

OCCURRENCE Very local along the eastern margin of the region covered by this book, recently expanding. Not known from Great Britain. ECOLOGY Broad-leaved forests with old trees and largesized dead wood, often near streams. Males sit on fallen logs and stumps along flushes in forest. Larva is wood-boring in wet decaying wood, where it lives on micro-organisms.

Bleached Falsehorn Temnostoma apiforme IDENTIFICATION 13–16 mm. A pale version of T. vespiforme. Face

without facial tubercle, with golden-yellow dusting and shiny black medial stripe; antennae orange. Postpronotum dusted yellow; margin before transverse suture with yellow dusted stripe, interrupted in middle; posterior corners of scutum and postalar calli black; scutum before scutellum with an indistinct yellow dusted spot. Wing: slightly dark. Mid and hind tibiae and tarsi orange, fore tibia and tarsus predominantly black. Tergites with narrow double bands on abdomen, especially band on posterior part of tergite 2 narrow and often interrupted in middle; bands on abdomen white–yellow, but sometimes more yellow like in T. vespiforme. SIMILAR SPECIES Much like T. meridionale, T. sericomyiaeforme and T. vespiforme, but stands out in the field by having narrower and usually more white–yellow bands on abdomen; best difference is lack of wedge-shaped spots on posterior corners of scutum; moreover, differs from T. sericomyiaeforme and T. vespiforme by yellow dusted stripe before transverse suture being interrupted in middle, creating two spots, whereas T. sericomyiaeforme with only single bands

on tergites. Pale parts of legs usually more orange–red instead of orange–yellow. OCCURRENCE Very local along the eastern margin of the region covered by this book. Not known from Great Britain. ECOLOGY Wet broad-leaved forests, forest edges, usually in the vicinity of a brook or stream. Flies low above the ground and visits flowers including those of buttercup. Like other Temnostoma, uses fore legs to imitate long wasp-like antennae by holding and moving them along head when in danger. Larva wood-boring in wet decaying wood.

Belted Falsehorn Temnostoma sericomyiaeforme IDENTIFICATION 14–18 mm. A convincing wasp mimic. Face

without facial tubercle; face with golden-yellow dusting and shiny black medial stripe; antennae orange. Several parts of scutum with yellow dusted marks: postpronotum, margin before transverse suture with an uninterrupted stripe, triangular spot before scutellum and posterior corners of scutum with wedge-shaped spots that continue over postalar calli. Wing: slightly dark. Mid and hind tibiae and tarsi yellow, fore tibia and tarsus predominantly black. Abdomen long oval; tergites 2–4 and in female also tergite 5 with a single wide yellow band, posterior margin with at most an indistinct transverse band of grey dusting; sternites 3 and 4 with dusted anterior margin. SIMILAR SPECIES This species has one wide band per tergite only, distinguishing it from all other Temnostoma except T. bombylans, but that species with more elongated abdomen, anterior part of wing much darker and posterior part of scutum without marks. Marks on scutum similar to T. vespiforme but, besides fewer bands on abdomen, sternites 3 and 4 only dusted along anterior

margin. OCCURRENCE A northern species that occurs south to Denmark. Not known from Great Britain. ECOLOGY Alder and willow carr with poplar and birch, including overmature and fallen trees. Flower visiting has been observed on umbellifers and Raspberry. Larva wood-boring, probably develops mainly in birch but also other broad-leaved trees.

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♂

♀

a b d o me n

da rk

4 ba nds 3 ba n ds

♂

a n te n n a

berberina

pa l e

e nti re l y pa l e -ha i re d dark hairs

♂

oxyacanthae

♀

a b d o me n

♂

pa l e tuf t

pale tuft a n te n n a

da rk

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Dusky Falsehorn Temnostoma bombylans IDENTIFICATION 12–16 mm. An elongated black Temnostoma

with narrow yellow bands on abdomen. Face without facial tubercle, with golden-yellow dusting and shiny black medial stripe; antennae short, orange. Postpronotum and margin before transverse suture yellow dusted, posterior half of scutum black. Wing: anterior half strongly darkened. Fore leg predominantly black, mid and hind legs extensively yellow. Abdomen of male with yellow band on anterior part of tergites 2–4, in female also on tergite 5. SIMILAR SPECIES Easily recognised; compared with other Temnostoma, usually smaller, anterior half of wing darker and abdomen more cylindrical. Moreover, combination of single yellow bands on tergites and scutum black in posterior part diagnostic. Gives a darker impression than other Temnostoma. Could maybe be mistaken for a Ceriana or Sphiximorpha species, but larger and antennae shorter than head. OCCURRENCE Northern Belgium and the Netherlands were colonised in the 1930–40s. Now widespread in continental

North-west Europe. Not known from Great Britain. ECOLOGY Wet, mature broad-leaved forests and historical parkland with welldeveloped undergrowth, in forest glades and along forest tracks. Flies 1–2 metres above the ground and sits on vegetation. Visits flowers of bushes and umbellifers. Uses black fore legs to imitate long antennae of wasps. Larva wood-boring in wet decaying wood.

Dimorphic Bumblefly Matsumyia berberina IDENTIFICATION 8–13 mm. A small to medium-sized, stocky, bumblebee mimic. Face extended downwards; face with facial tubercle; arista bare. Two roughly equally common colour morphs occur: oxyacanthae is entirely covered in orange–yellow to yellow–white hairs, berberina has body hairs consecutively orange, black and white–yellow (like in Bombus hypnorum). Tibiae with black hairs. Males: eyes almost meeting. SIMILAR SPECIES Could be mistaken for other bumblebee-mimicking hover-flies but combination of vein R4+5 straight or nearly so, face extended downwards and short hairs on arista distinguishes it from all species except those of Criorhina. Colour morph berberina not like any Criorhina; colour morph oxyacanthae like C. floccosa but smaller and stockier, tibiae with black hairs, hairs in upper corners of tergite 2 not conspicuously longer than surrounding hairs and third antennal segment paler, usually dark orange. OCCURRENCE A widespread and locally common species mostly found in mature woodland. ECOLOGY Damp and dry broad-leaved forest, alluvial forest, but in low numbers also in other drier woodland with ample dead wood and old trees. Flies quickly

through the forest edge. Visits assorted flowers, mainly flowering bushes such as hawthorn, and white umbellifers. Females can be seen investigating dead stumps but also the trunk bases of living trees. Larva lives in decaying wood of different broad-leaved tree species, for example, birch and European beech and possibly also coniferous trees. COMMENT Until recently, included in Criorhina but genetic evidence indicates it belongs to the genus Matsumyia.

Buff-tailed Bumblefly Criorhina floccosa IDENTIFICATION 12–15 mm. Medium-sized Criorhina mimicking

a bumblebee. Face extended downwards; face with facial tubercle; third antennal segment entirely brown–black or with dark-orange base; arista bare. Tibiae with pale hairs. Body with mainly vivid orange and white hairs. Front corners of tergite 2 with conspicuous tufts of long pale hairs, distinctly longer than surrounding hairs; tergites 2 and 3 can show variable amounts of black hairs. Males: eyes almost meeting. Female: abdomen with conspicuous buff-dusted tip when viewed from behind. SIMILAR SPECIES See M. berberina for differences with other Criorhina species. May be confused with colour morph oxyacanthae of M. berberina, but larger and more elongated, with a flatter, less furry abdomen that has conspicuously long and pale tuft of hairs on anterior corners of tergite 2, tibiae with pale hairs and third antennal segment usually darker. OCCURRENCE A widespread species in low numbers. ECOLOGY Prefers old (ancient) broad-leaved woodland and older hedgerows or historical parkland with mature trees; prefers forest with lots of poplar

and maple. Scarce in drier forests on the continent, but in Great Britain often in oak-dominated dry woodland and uses beech and oak there. Males keep territory at the foot of old broad-leaved trees and also patrol blossoms at great speed. Adult visits flowers of bushes and small trees (for example, hawthorn, holly) and sunbathes on leaves of trees. Larva lives in damp decaying wood in the trunk bases and dead roots of mature broad-leaved trees.

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♀

ab d o me n

head

♂

ti p usua l l y w hi te -ye l l o w

e x te nde d do w nwa rds ra re pa l e -ha i re d m o rph

♀ ♂

hind femur ti p som eti mes o ra n ge-red

s wolle n

♀

♂ oute r tars ome re s black

a b d o me n

p o steri o r si de ti bi a sh o rt-h a i red duste d spo ts

♂

head

f a ci a l tube rcl e ha rdl y sw o l l e n

♂

♂ long- haire d

♀

h i n d f e mu r

♀

abd o me n

head

ta rsi p a l e

e x te nde d do w nwa rds

stro ngl y sw o l l e n

♂

h i n d f e mu r

♀

h i n d f e mu r

sw o l l e n

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Large Bumblefly Criorhina ranunculi IDENTIFICATION 14–18 mm. A large dark bumblebee mimic.

Face extended downwards; face with facial tubercle; arista bare. Hind femur swollen, especially in male; hind tibia curved; fore and hind tibia with row of long hairs on outer side. Body mostly covered in black hairs except for tip of abdomen, which varies from reddish orange to white; sometimes scutellum with yellow hairs and rarely body entirely covered in yellowish-grey hairs. Male: eyes almost meeting. Female: frons with large dust spots along eye margin, covering three-quarters of width of frons. SIMILAR SPECIES See M. berberina for differences with bumblebee mimics that are not Criorhina species. In Criorhina easily recognised by the black hairs largely covering the body. The rare morph, with only pale hairs, can be confused with other Criorhina and Matsumyia; differs from M. berberina and C. floccosa by fore and hind tibia with row of long hairs on outer side; female differs from C. pachymera by more extensively dusted frons and male by wider abdomen, with sides not parallel;

differs from C. asilica by lack of pairs of stripes on abdomen, narrower black medial stripe on face and more extensively dusted frons. OCCURRENCE Widespread in the region covered by this book, but in low numbers; often overlooked since it often resides high up in sallow trees and flies early in the year. ECOLOGY Broad-leaved mature forests with ample mature trees. Prefers ancient woodland in Great Britain. Visits flowers of bushes such as Sallow, willow, cherry, Blackthorn or hawthorn. Males can be very aggressive to other insects around blossoms, even queen bumblebees, and patrol blossom at great speed. Females will inspect the trunk base of old trees and males sit or hover there. Larva lives in moist decaying wood at the base of broad-leaved trees.

Bee Bumblefly Criorhina asilica IDENTIFICATION 12–15 mm. A convincing bee-mimicking

Criorhina. Face extended downwards; face with facial tubercle, although indistinct in female; arista bare. Metasternum with hairs. Wing: with dark spots. Hind femur slightly swollen in male, not swollen in female; hind femur below without black spines; posterior side of fore and mid tibiae with short hairs; outer tarsomeres of tarsi black; underside of mid tarsus with black bristly hairs. Abdomen with pairs of grey-dusted spots on tergites 2–4, those on tergite 2 widest and most distinct. Male: posterior margin sternite 4 asymmetrical, with incision away from middle. Female: tergite 5 shiny; shiny black medial stripe on face very wide. SIMILAR SPECIES Owing to bee-like appearance of Criorhina species, mainly confused with C. pachymera; for differences, see that species. Like Brachypalpus but face extended downwards and with facial tubercle, hind femur less swollen and underside of hind femur without spines. Like Myolepta vara and M. obscura, but face extended downwards and with facial tubercle, crossvein r-m after middle of cell dm and vein M1 meets vein R4+5 well before wing-tip. OCCURRENCE Widely distributed over the range covered

by this book but mainly restricted to older woodland or wetlands with mature trees; prefers ancient woodland in Great Britain. ECOLOGY Large broad-leaved forests with overmature trees, often beech and oak forest. Males are hill-toppers. Often sits on leaves or at the trunk base of old broad-leaved trees. Visits flowers of bushes such as hawthorn or white umbellifers. Larva lives in decaying heartwood and roots of broad-leaved trees.

Poplar Bumblefly Criorhina pachymera IDENTIFICATION 13–19 mm. A large bee-mimicking Criorhina.

Face extended downwards and with facial tubercle; arista bare. Scutum with dusted longitudinal stripes; metasternum with hairs. Hind femur strongly swollen, especially distinctive in male; posterior side of fore and mid tibiae with long hairs; hind femur below without black spines; tarsi entirely orange; underside of mid tarsus with yellow bristly hairs. Male: face entirely dusted; abdomen long, slender and cylindrical, with parallel sides. Female: face with narrow medial stripe; frons along eye margin with narrow dust spots, together covering a quarter of width of frons. SIMILAR SPECIES Like Brachypalpus and Myolepta; for differences, see C. asilica. For differences with pale morph of C. ranunculi, see that species. Like C. asilica but tarsi pale, tergite 2 without distinct grey-dusted pair of spots, underside of mid tarsus with yellow bristly hairs, posterior side of fore and mid tibiae with longer hairs, male hind femur much more swollen and posterior margin sternite 4 symmetrical, female with large part of tergite 5 dusted. OCCURRENCE Very localised and in low numbers; often in

mature poplar plantations that are not well investigated so could be overlooked. Not known from Great Britain. ECOLOGY In Northwest Europe, mostly confined to poplar plantations and lanes bordered with old poplars. Also in old broad-leaved forests with beech, often found at the base of overmature poplar and beech. Territorial males make a loud buzzing sound when sitting. Often visits upper part of flowering bushes such as hawthorn. Larval biology unknown, but egg-laying has been observed at the base of broad-leaved trees.

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♂

a b d o me n

hea d rel a ti v e l y sm a l l

ba re co nvi nci ng bum bl ebe e m i m i c

♂

♀

♂

head

a b d o me n si de m a rgi n ye l l o w

d usted

no f a ci a l tube rcl e

♂

usua l l y ye l l o w

head

e ye s to uchi ng a ri sta da rk

♂

hind t ib ia

duste d

without proje ction

♂

♂

head

♀

head

head

♂

gre y duste d bl a ck m e di a n stri pe

♀

a ri sta ye l l o w

head

shi ny

♂

hind ti b i a

p o i nted pro j e cti o n

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Eurasian Pocota Pocota personata IDENTIFICATION 12–13 mm. Very convincing mimic of Whitetailed bumblebee. Face without facial tubercle; face not extended downwards; arista bare. Head appears relatively small due to very long hairs on scutum. Body with dense lemon-yellow, black and white hairs. Wing: dark spot in middle; vein M1 meets vein R4+5 only just before wing-tip; vein R4+5 straight or nearly so. Male: eyes meeting. SIMILAR SPECIES Differs from similar-looking bumblebee-mimicking hoverflies by combination of: vein R4+5 straight or nearly so, crossvein r-m after middle of cell dm, cell r1 open, arista bare and face without facial tubercle. In general, appearance closest to Sericomyia bombiformis but scutellum with black hairs, tergite 3 instead of tergite 2 with pale hairs, arista bare, face not extended downwards and flies earlier in the season. OCCURRENCE Widespread but very scarce, a rarity in most of its range but perhaps prone to being under-recorded because it needs targeted searching. ECOLOGY Broad-leaved forests and historical parkland with veteran trees with cavities, especially

beech and sycamore but sometimes associated with isolated trees in farmland with rot holes. Probably lives high in broad-leaved trees but comes down to visit flowers of, for example, hawthorn, Cherry laurel and Rowan. Can be found resting at the entrance of wet cavities or on and around the base of old broad-leaved trees. Males will hover at 2–3 metres but in a rather laboured manner with the body held at an angle. Larva lives in wet tree cavities.

Thick-thighed Forest Fly Brachypalpus laphriformis IDENTIFICATION 10–12 mm. Face without facial tubercle; arista dark brown, face in middle usually yellowish but sometimes entirely dark. Metasternum bare; transverse suture and notopleuron dusted grey. Wing: with two dark spots. Hind femur strongly swollen and with spines below. Sides of tergites 1 and 2 yellow, if sides black: morph meigeni; tergites 2–4 without grey dust spots. Male: eyes meeting over considerable distance; hind trochanter with small blunt tubercle; hind tibia below without pointed projection; hairs on hind tibia not longer than width of hind tibia. Female: frons dusted; hind trochanter at least yellow below; hind tarsus with tarsomere 2 over twice longer than wide. SIMILAR SPECIES For differences with species other than B. valgus, see that species. Similar to B. valgus but arista dark, smaller, with slightly less denser hairs and hairs slightly paler; transverse suture and notopleuron dusted and face not yellow with black medial stripe; furthermore, male eyes meeting over a longer distance and hind tibia below halfway without pointed projection, and female with dusted frons, hind trochanter partly or entirely yellow and tarsomere 2 of hind tarsus longer. OCCURRENCE Widespread

and relatively frequent in forests on the continent; widespread but scarce in Great Britain. Present disproportionally in Malaise trap catches, indicating it may often go unnoticed flying about on the forest floor. ECOLOGY Broad-leaved forests with overmature trees, forest fragments, wood pasture. Males sit on tree stumps or trunks. Visits flowers of flowering bushes, small trees and umbellifers. Larva develops in the wet, sloppy wood mould found in rot holes and heart-rot of old broad-leaved trees, but also reported from coniferous trees.

Greater Forest Fly Brachypalpus valgus IDENTIFICATION 11–14 mm. A convincing bee mimic. Face without facial tubercle; face dark yellow with black medial stripe, although sometimes indistinct due to grey dusting on face, arista yellow. Metasternum bare; transverse suture and notopleuron shiny. Wing: with dark spots. Hind femur swollen, below with black spines. Male: eyes almost meeting; hind trochanter with a small blunt tubercle; hind tibia strongly curved and below with pointed projection before halfway; hairs on hind tibia longer than width of hind tibia. Female: frons shiny, dusted only along eye margin; hind trochanter black; tarsomere 2 of hind tarsus less than twice longer than wide. SIMILAR SPECIES Much like B. laphriformis; for differences, see that species. Like Chalcosyrphus eunotus but that species has more extensive grey dust spots on scutum and tergite 2, metasternum has hairs and black spines below on hind femur restricted to tip. Like Myolepta vara and M. obscura but, amongst other differences, crossvein r-m after middle of cell dm and vein M1 meets vein R4+5 well before wing-tip. Like Criorhina pachymera but that species lacks black

spines below on hind femur, has face extending downwards and has face with facial tubercle. OCCURRENCE Along the eastern and southern margin of the range covered by this book; unclear why it is largely absent from Belgium and the Netherlands. Not known from Great Britain. A very early species but with relatively long flight period. ECOLOGY Mainly in mature oak and beech forests with overmature trees. Often visits low spring forest flowers such as Wood anemone, Lesser celandine and Coltsfoot. Males often sit on the forest floor near old trees. Larva has been found in decaying wood of Common alder and oak.

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♀

a b d o me n

l a rge gre yduste d spo ts

♂ grey-dusted l o ngi tu di na l stri p es

♂

head

f a ce bl a ck w i th gre y dusti ng

♀

♂

a b d o me n

k nob halte re gre y or black b ro w n-ye l l o w

hind leg

sho rt ho o k

♀

a b d o me n

♂

k nob ha l tere brown– yel l ow

s trongly s wol l en and with long h a i rs

da rk bro w n

hind leg di sti nct ho o k

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Logjammer Chalcosyrphus eunotus IDENTIFICATION 9–11 mm. The only Chalcosyrphus that mimics

a bee. Face black with grey dusting; face without facial tubercle. Scutum with grey-dusted longitudinal stripes; metasternum with long hairs; tergite 2 with pair of wide grey-dusted spots. Hind femur swollen and below with black spines near its tip. Wing: with two dark spots. Male: eyes meeting; hind trochanter without blunt tubercle. SIMILAR SPECIES Does not look like other Chalcosyrphus at all, but similar to bee-mimicking species from other genera. Like Brachypalpus but tergite 2 with pair of grey-dusted spots, scutum with grey-dusted longitudinal stripes, face always black, hind femur below only near tip with black spines and metasternum with hairs. Like Criorhina asilica and C. pachymera, but face not extended downwards and face without facial tubercle. Like Myolepta vara and M. obscura, but these species have crossvein r-m just before middle of cell dm and vein M1 meets vein R4+5 only at wing-tip. OCCURRENCE Localised in the southern part of the range covered by this book both in Great Britain and

on the continent. Scarce. To find this species requires searching its specific habitat: log-jams in small, often steep-sided streams. It is clearly expanding in Belgium and may profit from beaver activity. ECOLOGY A species with strict habitat requirements: streams and brooks in broad-leaved forests with large semi-submerged logs and branches. They fly around the stream and sit on log-jams or nearby sunlit vegetation, males hold territory there. Larva lives in dead wood that lies in flowing water.

Lesser Orange-thighed Leafwalker Chalcosyrphus valgus IDENTIFICATION 12–15 mm. A distinctive species with black elongated abdomen and bright orange legs. Face black, without facial tubercle; antennae orange, arista bright orange. Wing: haltere knob grey or black; pterostigma brown–yellow. Fore and mid legs almost or entirely orange–red, hind leg with hind femur largely orange, but tip and remainder of leg black; hind tibia with short hook at tip. Male: hairs on tibiae much shorter than width of tibiae. SIMILAR SPECIES Once recognised as a hoverfly, confusion with species other than C. femoratus impossible. Like C. femoratus but on average smaller, haltere knob grey or black instead of yellow–brown, pterostigma brown–yellow instead of dark brown, hind tibia with shorter hook at tip, arista orange instead of dark red–brown and male with shorter hairs on tibiae. OCCURRENCE A local species in the range covered by this book, but can be frequent in areas with large spruce plantations. Not known from Great Britain. A strong hill-topper. ECOLOGY In large mixed and coniferous forests with overmature spruce. Often sits on spruce logs or on leaves of bushes. Visits flowering bushes and white umbellifers. Larval biology poorly known,

probably in wood of coniferous trees. COMMENT See comment at C. femoratus.

Greater Orange-thighed Leafwalker Chalcosyrphus femoratus IDENTIFICATION 14–18 mm. Remarkable species: abdomen elongated and black, legs bright orange. Face black, without facial tubercle; antennae orange, arista dark red–brown. Wing: haltere knob brown–yellow; pterostigma dark brown. Fore and mid legs almost or entirely orange–red, hind leg with hind femur predominantly orange, but tip and remainder of leg black; hind tibia with distinct hook at tip. Male: hairs on tibiae longer than width of tibiae. SIMILAR SPECIES Confusable only with C. valgus; for differences, see that species. OCCURRENCE A very rare and local species on the eastern margin of the range covered by this book. Not known from Great Britain. Mostly singletons are seen, but can occur in large number at hill-tops. ECOLOGY Large, old and mature broad-leaved forests with overmature oak or beech. Walks nervously over leaves of bushes in the sun and sits on freshly felled trunks and stumps. Flies very fast through flowering bushes and visits flowers of hawthorn, Guelder-rose, white umbellifers and Raspberry. Larva undescribed, but found in decaying birch wood. COMMENT Nomenclature of C. valgus and C. femoratus

has a turbulent history. Confusingly, earlier C. valgus was called C. femoratus and often C. femoratus was called C. curvipes, but the nomenclature used in this book is correct.

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♂

a b d o me n te rgi te s 2 a nd 3 w i de r tha n l o ng

re cta ngul a r spo ts

♂

stro ngl y sw o l l e n

hind leg

wi tho ut pro j e cti o n

met as t er num

na rro w l y ye l l o w

sho rt e re ct bl a ck ha i rs

l o ng h a i rs

♀

♂

a b d o me n

ti p o f a bdo m e n re d

♂

l e gs bl a ck

head

w e a k l y co nca v e ti p of a b do m en red

♀

a b d o me n

♂ l e gs bl a ck

ti p o f a bdo m e n bl a ck

♂

ti p of a b do m en b l a ck

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stro ngl y co nca v e

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Small Leafwalker Chalcosyrphus nemorum IDENTIFICATION 7–10 mm. A small stocky Chalcosyrphus. Fore

tarsus with tarsomeres 1 and 2 yellow; only very base of hind tibia yellow; hind femur strongly swollen; underside of hind tibia entirely covered with short erect black hairs. Metasternum with long hairs. Abdomen with pairs of orange–yellow rectangular spots on tergites 2 and 3, sometimes reduced in females; tergites 2 and 3 distinctly wider than long. Male: hind trochanter without projection; tergite 8 with golden-yellow hairs. Female: frons before ocellar triangle short and wide, as long as second and third antennal segments combined; frons with wide grey-dusted transverse band above antennae. SIMILAR SPECIES Owing to spots on abdomen, unlike other Chalcosyrphus species but similar to some Xylota. Differs from Xylota by having long hairs on metasternum. Easier field character is narrower yellow base of hind tibia; only X. abiens shares narrowly yellow base of hind tibia, but that species has tergite 2 squarish, hind femur less swollen (compare by sex), hind tibia below not entirely covered with erect

black hairs; male has hind trochanter with tubercle, and female has frons narrower. OCCURRENCE A widespread and frequent woodland species with a long flight period. ECOLOGY Preferentially in wet broad-leaved forests, alder and willow carr, but also small numbers in drier forest, especially that with beech. Sits on leaves of bushes but also frequently visits flowers. Larva lives under bark and in cavities of wet broad-leaved wood.

Red-tailed Leafwalker Chalcosyrphus piger IDENTIFICATION 11–13 mm. A species with predominantly red abdomen and entirely black legs. Face without facial tubercle, black; frons at level of antennae moderately protruding; antennae black. Metasternum with long hairs, but hairs are adpressed and can easily be missed. Wing: apical half dark. Legs black; hind femur strongly swollen. Tergite 1 and anterior margin of tergite 2 black; remainder of abdomen including tip red, but tip may be dark somewhat; anterior margin of red marking on tergite 2 with black incision; tergites 2 and 3 with very short white and black hairs. SIMILAR SPECIES Several Xylota species share predominantly red abdomen, but have legs partly pale. Like Brachypalpoides lentus but tip of abdomen red; if unsure, distinguished by metasternum with long hairs, face at level of antennae not conically protruding forward and tergites 2 and 3 without dense yellow hairs. OCCURRENCE This species had largely disappeared from North-west Europe by the end of the 20th century, but has since made a remarkable comeback. Now widespread and locally common. Recently discovered in England. ECOLOGY Old pine or larch forests, with many tree stumps and logs. Males sit on

sunlit trunks of fallen trees. Visits flowers of flowering bushes and buttercup. Larva lives in moist wood under bark of pine and larch.

Crimson-belted Leafwalker Brachypalpoides lentus IDENTIFICATION 11–14 mm. Fairly large, red and black species with elongated abdomen. Face without facial tubercle, black; face at level of antennae conically protruding forwards; antennae black. Metasternum with very short hairs, almost bare. Wing: apical half slightly dark. Legs black; hind femur moderately swollen. In male tergites 2 and 3, and in female also anterior quarter of tergite 4, red; base and tip of abdomen black; anterior margin of red mark on tergite 2 usually with a small black V-shaped incision in middle; tergites 2 and 3 with golden-yellow hairs, hairs erect and fairly long in male, shorter and more adpressed in female. SIMILAR SPECIES Several Xylota species share largely red abdomen, but have legs partly pale. Like Chalcosyrphus piger but tip of abdomen black; for additional differences, see that species. OCCURRENCE A widespread species of North-west European broad-leaved woodland, especially damp ancient woodland in Britain. ECOLOGY Damp broad-leaved woodland with mature and overmature trees. Restless, runs on leaves, flying nervously from one to the other. Males sit at the trunk base of large trees. Larva

has been found in decaying wood or under bark of broad-leaved trees, but also in spruce.

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♂ firs t two tars ome re s pale

a b d o me n

te rgi te s 2 a nd 3 w i de r tha n l o ng

m et as t er num hind leg ti p of a b do m en wh i te-ha i red a pprox . 2 0 % ye l l o w bare

♂

♀ ♀

a b d o me n

hin d l e g

bas al two tars ome re s pale onl y b a se h a i re d a pprox . 3 0 % ye l l o w

A n e p i ste rn u m po ste ri o r duste d a ne pi ste rnum

te rgite 2 s quare bl a ck-h a i re d

♂ tip of abdomen ♀

♂ ♀

hind leg

a b d o me n

sho rt-ha i re d

bas al thre e tars ome re s pale

a pprox . 3 0 % ye l l o w

A n e p i ste rn u m a nte ri o r shi ny a ne pi ste rnum

te rgite 2 longe r than wide

wh i te-ha i red

♂ tip of abdomen

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Alder Leafwalker Xylota abiens IDENTIFICATION 8–10 mm. A small Xylota with pairs of orange–

yellow spots on abdomen. Face flat and black; antennae dark. Anepisternum dusted. Tergites 2 and 3 with pairs of rectangular to trapezoidal orange–yellow spots that may be strongly reduced in female; tergites 2 and 3 slightly wider than long, or squarish. Fore tarsus with tarsomeres 1 and 2 yellow; about a fifth or a sixth of base of hind tibia dark yellow, transition to dark part indistinct; hind femur moderately swollen. Male: frons almost entirely dusted except a small area behind antenna attachment; scutum with pale hairs; tergite 8 with pale hairs; hind trochanter with small tubercle. Female: dust band on frons with straight posterior margin. SIMILAR SPECIES Much like Chalcosyrphus nemorum; for differences, see that species. Differs from similar-looking Xylota with spots on abdomen by having narrower and darker yellow base of hind tibia, so with less distinct contrast to remaining black tibia, about basal 10–20% instead of 30% yellow. Furthermore, differs from X. meigeniana and X. florum by having basal two,

instead of three, tarsomeres of fore tarsus yellow and male by wider tergite 2. Like X. jakutorum but that species has, besides more extensively yellow base of hind tibia, black hairs on tergite 8 and frons less extensively dusted in male and female has posterior margin of dusting on frons with deep incision. OCCURRENCE A widespread but very local species. ECOLOGY Old wet broadleaved forests with overmature trees such as alder, and flushes or streams, especially forest that is waterlogged or flooded during winter. Sits on fallen trees and trunks, but also on leaves, up to 1.5 metres from the ground. Not frequent on flowers. Larva lives in sap runs and roots of decaying trees.

Spruce-stump Leafwalker Xylota jakutorum IDENTIFICATION 10–12 mm. A Xylota with pairs of orange– yellow spots on abdomen. Face flat and black; antennae dark. Anepisternum entirely covered in thin dusting, weakly shiny. Basal third of hind tibia yellow; basal one-quarter to one-third of outer upper side hind femur with moderately long hairs; tarsomeres 1 and 2 of fore tarsus yellow. Tergites 2 and 3 with pairs of orange–yellow spots; tergite 2 slightly wider than long, or squarish. Male: frons dusted except a wide shiny area behind antenna attachment; pair of spots on tergite 2 roughly rectangular; tergite 8 with black hairs. Female: frons with wide dust band, posterior margin of dust band with deep incision. SIMILAR SPECIES Like Chalcosyrphus nemorum, but larger and more elongated, base of hind tibia more extensively yellow and male has black hairs on tergite 8. Like X. abiens, but base of hind tibia yellow for 30% instead of 10–20%, male with black hairs on tergite 8 and female has posterior margin of dust band on frons with deep incision. Differs from X. meigeniana and X. florum by having basal two, instead of three, tarsomeres of fore tarsus yellow, hairs on hind femur more restricted to basal

part (compare by sex), and male by roughly square tergite 2 with rectangular spots. OCCURRENCE Mainly in low mountain areas on the continent, in Great Britain mainly in the north and west; locally abundant. Much increased in Great Britain as conifer plantations have matured sufficiently to support it. ECOLOGY Wet coniferous forests; in Great Britain often in pine forest and dry spruce plantation, on the continent restricted to spruce plantations. Walks nervously on leaves of bushes along forest glades. The only Xylota that frequently visits flowers including white umbellifers and buttercups. Larva has been found in sap runs of coniferous trees and in borings of Hylobius weevils in spruce stumps.

Smoky-winged Leafwalker Xylota meigeniana IDENTIFICATION 8–12 mm. A slender Xylota with pairs of orange– yellow spots on abdomen. Face flat and black; antennae dark. Anepisternum entirely undusted, shiny. Wing: apical half dark (except in fresh individuals), contrasting with transparent basal half. Basal three tarsomeres of fore tarsus yellow; basal third of hind tibia yellow; basal two-thirds of outer upper side hind femur with white hairs of similar length, hairs not longer than quarter of hind femur width. Tergites 2 and 3 with pairs of orange–yellow spots. Male: pair of spots on tergite 2 oval; tergite 2 much longer than wide; tergite 8 with pale hairs. Female: dust spots on frons not connected, not forming a band. SIMILAR SPECIES Like Chalcosyrphus nemorum, X. abiens and X. jakutorum, but basal three, instead of basal two, tarsomeres of fore tarsus yellow and in male tergite 2 distinctly longer than wide. Like X. florum but smaller, hind femur for a shorter length covered in slightly shorter white hairs, anepisternum entirely shiny (although difference subtle) and male with white hairs on tergite 8. Some females of X. tarda with red markings on abdomen reduced to spots, similar

to in X. meigeniana, but pairs of spots on abdomen still larger, and middle part of hind femur below with dense short black spines instead of with adpressed golden-yellow hairs. OCCURRENCE A rare species, with the southern limit of its range coinciding with that of the range covered by this book. Widely scattered populations along the eastern part of the range covered by this book. Very localised. Has strongly declined in northern Belgium. Not known from Great Britain. ECOLOGY Alluvial forest, alder carr, along streams and brooks in old wet broad-leaved forest, with overmature trees. Often near Aspen stands. Irregularly visits flowers of, for example, white umbellifers. Larva has been reared under bark of rotting wood of Aspen.

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♂

♀

severa l l o ng w hi te ha i rs

a b d o me n

bas al thre e tars ome re s pale

♀

hin d l e g

a pprox . 3 0 % ye l l o w shi ny

te rgite 2 longe r than wide

duste d

bl a ck-h a i red

♂

tip of abdomen A n e p i ste rn u m

♀

♂

a b d o me n

ti p ti bi a e bl a ck

hind leg

bo tto m ha l f o f ti bi a bl a ck

♀

a b d o me n

♂

a l l ti bi a e ye l l o w

hind leg o ften w i th va gue yel l o wi sh spo ts ti bi a e nti re l y ye l l o w

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Slim-tailed Leafwalker Xylota florum IDENTIFICATION 10–13 mm. A large Xylota with pairs of orange– yellow spots on abdomen. Face flat and black; antennae dark. Anterior anepisternum dull, posterior anepisternum shiny; look carefully, this is a difficult and subtle character to assess and anepisternum may seem entirely shiny. Basal three tarsomeres of fore tarsus yellow; basal third of hind tibia yellow; basal 80% of outer upper side hind femur with white hairs, length of hairs a third or a quarter of hind femur width, some hairs longer, about half hind femur width. Tergites 2 and 3 with pairs of orange–yellow spots. Male: frons dusted except a wide shiny area behind antenna attachment; tergite 2 longer than wide; spots on tergite 2 oval; tergite 8 with black hairs. Female: dust spots on frons not connected, not forming a band. SIMILAR SPECIES Slightly larger than similar Xylota. Black hairs on tergite 8 of male shared only with X. jakutorum but that species has basal two, instead of basal three, tarsomeres of fore tarsus yellow and anepisternum thinly dusted. Female has basal three tarsomeres

of fore tarsus yellow and dust spots on frons not connected, a combination also found only in X. meigeniana, but distinguished by being larger, hind femur with larger part with longer hairs, and anterior anepisternum dull (a difficult character though). OCCURRENCE Widespread but local. Has strongly declined in northern Belgium. ECOLOGY Mainly mature damp broad-leaved forest, often with poplar and near streams, but also in damp spruce plantations with overmature trees. Found on fallen trees, log piles and on leaves along forest tracks. Larva has been found repeatedly in cavities of poplar, but also spruce.

Golden-tailed Leafwalker Xylota sylvarum IDENTIFICATION 11–16 mm. A large Xylota with golden hair patches on abdomen. Face black; mouth edge partly yellow; antennae black. Basal half of tibiae yellow, apical half black, but on anterior side pale; black marking not obvious from every angle owing to dense golden-yellow hairs covering tip. Abdomen black, anterior corners of tergite 3 and tergite 4 entirely covered in adpressed golden-yellow hairs; tergite 8 in male, tergite 5 in female, largely with black hairs. SIMILAR SPECIES Can be confused only with X. xanthocnema; best difference is black tip of tibiae, but dense golden hairs on the tibia light up at certain angles, making tibia appear yellow; additional helpful characters of X. sylvarum are usually larger size, absence of yellowish spots on tergite 2 and 3, and male with largely black hairs on tergite 8 and in female tergite 5. OCCURRENCE A widespread and frequent woodland species. ECOLOGY Both damp and drier coniferous, mixed and broad-leaved woodland, city parks. Most abundant in broadleaved woodland with plentiful dead wood and bramble. Walks nervously over leaves and quickly flies to the next leaf. Seldomly visits flowers, males hover at hill-tops. Larva lives under bark, in

decaying wood or in decaying roots of assorted tree species both broad-leaved and coniferous.

Yellow-shinned Leafwalker Xylota xanthocnema IDENTIFICATION 9–13 mm. Resembling X. sylvarum but with

entirely yellow hind tibia. Face black; mouth edge black; antennae black. Tibiae entirely yellow, sometimes hind tibia with small black streak at tip. Anterior corners of tergite 3 and tergite 4 entirely covered in adpressed golden-yellow hairs; tergites 2 and 3 often with vague yellowish pair of spots (thus not only with golden hairs); tergite 8 in male, tergite 5 in female, mostly with golden-yellow hairs. SIMILAR SPECIES Easily recognisable; with X. sylvarum the only Xylota with golden-yellow hairs on tip of abdomen. Like X. sylvarum but usually smaller, tibiae entirely yellow, often with indistinct pair of spots on tergites 2 and 3, and in male mostly golden-yellow hairs on tergite 8 and in female tergite 5. OCCURRENCE Widespread but scarce and local. ECOLOGY Old damp broad-leaved forests, along forest tracks and forest glades. Nervously walks on the leaves of bushes or largeleaved herbs. Also found near stumps and felled wood. Often at more damp and more shaded places compared to X. sylvarum. Larva lives in cavities and sap runs of trees. HOV E R FL I E S OF B R I TAI N AN D N ORT H-WE S T E UR OPE ⁞ 3 9 3

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♂

♀

abdomen

♂

h i n d l e g d e ta i l

sho rt bl a ck spi ne s

♂

hind leg

l ong, sl e nde r spur ro w o f l o ng spi ne s ti p bl a ck

♂

♀

a b d o me n

de e p i nci si o n

♂

hind leg

sho rt, bl unt spur sho rt spi ne s ti p bl a ck

♀

a b d o me n

♂

♂

sho rt spur

hind leg

sho rt spi ne s ti p ye l l o w

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Orange-belted Leafwalker Xylota segnis IDENTIFICATION 10–13 mm. A familiar Xylota with largely

orange–red abdomen. Face without facial tubercle; face black, covered in silverish dusting; mouth edge black; antennae dark. Anepisternum thinly dusted. Legs partly pale, at least base of tibiae and basal tarsomeres yellow; hind femur below at tip with a double row of black spines, outer row reaching basal half of femur, in male almost reaching base; underside of hind tibia at base with a dense row of short black spines, standing out against yellow background. Tergites 2 and 3 extensively orange–red; tip of abdomen black. Male: hind trochanter with long slender spur. SIMILAR SPECIES Owing to combination of largely red abdomen and partly pale legs, can be confused only with X. tarda and X. ignava; for differences with X. ignava, see that species. Like X. tarda but base of hind tibia below with short black spines and outer row of black bristles below at tip of hind femur reaching basal half; moreover, usually slightly larger, with brighter orange abdomen with smaller incisions, with thinly dusted anepisternum

and hind trochanter of male with longer spine. OCCURRENCE Our most widespread Xylota, occurring also away from woodland. ECOLOGY Both dry and wet forests, but also in more open areas such as parks, gardens, agricultural land with hedges. Walks nervously over leaves of scrubs, brambles or on the ground. Seldom visits flowers. Larva lives in decaying wood, in sap runs, under bark, compost heaps, wood dust etc.

Aspen Leafwalker Xylota tarda IDENTIFICATION 9–10 mm. A small Xylota with red markings

on abdomen. Face without facial tubercle; face black with silver dusting; mouth edge black; antennae dark. Anepisternum shiny. Legs partly pale; fore and mid tibiae yellow with black ring, hind tibia yellow at base but otherwise dark up to tip; hind femur below covered with many short black spines; hind tibia below at base without black spines. Tergites 2 and 3 predominantly orange–red or red, anterior margin often with deep incision; in female posterior margin of tergite 2 usually black and red marking has an incision on anterior and posterior margins, making red markings sometimes reduced to pairs of spots. Male: hind trochanter with short, blunt spur. SIMILAR SPECIES Could be confused with X. ignava but much smaller and tibiae with different colour distribution. Especially similar to X. segnis; for differences, see that species. If red markings on abdomen reduced to pairs of spots, keys out to X. meigeniana, but that species has spots on abdomen smaller and hind femur below in middle with adpressed golden yellow hairs instead of short black spines. OCCURRENCE A widespread but localised species that generally occurs in low

numbers. ECOLOGY Damp alluvial forests with poplar and Aspen, forest glades in wet broad-leaved forests. In Great Britain, seems to be almost exclusive to Aspen-rich ancient woods. Restless, flies a lot and quickly walks back and forth on leaves. Larva lives in sap runs and in decaying wood, with a supposed strong preference for Aspen and other poplars.

Red-belted Leafwalker Xylota ignava IDENTIFICATION 11–15 mm. Face without facial tubercle; face black covered with golden-yellow dusting; mouth edge yellow in middle; antennae dark. Scutum with blueish sheen; anepisternum dusted. Legs partly pale; fore and mid tibiae entirely yellow or with indistinct black smudge, but not with distinct black ring; hind tibia yellow with black ring in middle; underside of hind femur with many small black spines and widening before tip, with keel, making underside of hind femur somewhat undulating. Tergites 2 and 3 predominantly orange, tergite 2 anteriorly in middle with an incision. Male: hind trochanter with spur. SIMILAR SPECIES Owing to partly pale legs and largely orange–red abdomen, will mainly be confused with X. segnis and X. tarda, but colour distribution of legs different: fore and mid tibiae entirely yellow or only with black smudge and tip of hind tibia yellow, versus in other two, fore and mid tibiae with black ring and hind tibia with black tip. Hairs and spines below at hind femur and hind tibia like in X. tarda, but that species, besides above-mentioned characters, much smaller, underside of hind femur not undulating, has a black

mouth edge and shiny anepisternum. Unlike X. segnis lacks row of black bristles below at base of hind tibia and lacks large black spines below on basal part of hind femur; furthermore, male with shorter spur on hind trochanter. OCCURRENCE A rare and local species in low mountain ranges, only at the eastern margin of the range covered by this book. Not known from Great Britain. ECOLOGY Spruce plantations or mixed forests with spruce. Walks on leaves in the forest edge, sometimes visits bushes in flower and white umbellifers. Sits on tree stumps or on the ground near felled wood. Larval biology unknown.

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Swamp Thickleg Tropidia scita IDENTIFICATION 7–11 mm. Face profile roof-shaped, tapering towards shiny black medial stripe, therefore medial stripe on a longitudinal keel; third antennal segment brown to black. Scutum shiny black with short golden-yellow hairs; sides of thorax with thick grey dusting. Wing: vein M1 meets vein R4+5 only just before wing-tip; vein R4+5 with a shallow dip into cell r4+5. Hind femur swollen and tip below with a large triangular process; hind femur black with dense, very short, adpressed and therefore difficult to notice black hairs. Tergites 2 and 3 predominantly orange–red, with black medial stripe. SIMILAR SPECIES Somewhat resembling Xylota, but more robust; hind femur below at tip with large triangular process, vein R4+5 with a shallow dip, and vein M1 meets vein R4+5 only just before wing-tip. Like Myolepta dubia and M. potens but crossvein r-m after instead of before middle of cell dm, vein R4+5 with a shallow dip and wings without dark spot. Like much rarer T. fasciata; for differences, see that species. OCCURRENCE Widespread in lowland wetlands. ECOLOGY Wetland

habitats with lush emergent vegetation (reeds, Reed sweet-grass). Marshes, swampy ditches, pool margins, river margins and fens. In Great Britain, most frequent in the ditches of coastal grazing marsh and flood plains inland. Flies low above the ground and sits on low vegetation. Visits flowers including those of buttercups and Yellow flag. Males hover among vegetation. Larva probably lives in decaying plant material at the water’s edge.

Hairy Thickleg Tropidia fasciata IDENTIFICATION 10–12 mm. Rare relative of T. fasciata. Face roof-shaped, tapering towards shiny black medial stripe, therefore medial stripe on a longitudinal keel; at least lower half of third antennal segment orange. Sides of thorax with thick grey dusting; scutum bronze coloured, slightly dusted and with two grey-dusted longitudinal stripes anteriorly; scutum with long erect golden-yellow hairs. Wing: vein M1 meets vein R4+5 only just before wing-tip; vein R4+5 with a deep dip into cell r4+5. Hind femur swollen and below at tip with large triangular process; hind femur dark in male but with wide orange base in female; all femora with long pale hairs. Abdomen with pairs of orange spots. SIMILAR SPECIES For differences with Xylota and Myolepta, see T. scita. Somewhat like Merodon but with keel on face and vein M1 meets vein R4+5 only just before wing-tip. Similar to much commoner T. scita but spots on abdomen less bright red, scutum bronze coloured, duller and with longer hairs, femora with much longer hairs; above-mentioned differences create a very different impression in the field. Furthermore, vein R4+5 with deeper dip into cell r4+5, third antennal segment paler and

female with yellow base of hind femur. OCCURRENCE A very local species restricted to the southern margin of the range covered by this book. Can be abundant in suitable habitat. Not known from Great Britain. ECOLOGY Unimproved meadows and pasture, waterlogged with base-rich groundwater. Often in floristically exceptional grasslands, the so-called Molinia meadows on calcareous, peaty soil. Flies low and fast, and settles on low vegetation. Visits low flowers such as those of buttercups and Common tormentil. Larval biology unknown.

Common Compost Fly Syritta pipiens IDENTIFICATION 5–9 mm. A small, slender species with a strongly swollen hind femur. Face without facial tubercle, with dense silvery dusting; third antennal segment largely orange–red. Sides of thorax with dense grey dusting; anterior corners of scutum up to transverse suture with dense grey dusting; scutum anteriorly with two short grey-dusted longitudinal stripes. Hind femur strongly swollen and below with black spines; hind femur black with a large orange spot halfway. Abdomen with pairs of orange–yellow spots of descending size on tergites 2–4, pairs of spots usually grey-dusted in female, in male only pair on tergite 4 dusted; abdomen especially in male slightly constricted, tergite 3 narrower than tergites 2 and 4. SIMILAR SPECIES Looks a bit like Xylota species owing to elongated abdomen and swollen hind femur, but, amongst other differences, smaller and slenderer and sides of thorax and anterior corners scutum with dense grey dusting; behaviour different, not walking nervously over leaves like Xylota. Somewhat similar to Neoascia, but hind femur halfway with orange spots and anterior corners scutum and sides of thorax

with dense grey dusting, and scutum with dusted longitudinal stripes. OCCURRENCE A widespread and very frequent species, both in natural, urbanised and agricultural land. ECOLOGY Various habitats: marshes, watersides, wet forests, agricultural fields, suburban areas, etc. Flies low over low vegetation and visits a variety of flowers; males constantly fly through the flowers looking for females. Virtuoso flier, male battles and courtship behaviours have a slow-motion vibrating flight. Larva lives in decaying organic matter in moist environments such as compost heaps.

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Index Bold pagination refers to the text page of a species account. Alder Halfband 80, 82, 123 Alder Leafwalker 100, 391 Anasimyia contracta 88, 347 interpuncta 88, 345 lunulata 88, 345 transfuga 88, 347 Anthracine Haireye 34, 357 April Halfband 80, 82, 119 Arctophila bombiformis 355 mussitans 355 Aspen Leafwalker 100, 395 Aspen Logsitter 64, 293 Atlantic Mucksucker 36, 315

Baccha elongata 30, 211 Banded Thintail 80, 115 Bankowska’s Globetail 76, 78, 173 Bare-legged Sedgesitter 58, 62, 189 Barred Dayglower 66, 177 Barred Flower Fly 74, 127 Bear Fly 66, 147 Bearded Spruce Blacklet 48, 50, 227 Bee Bumblefly 94, 383 Beech Sapeater 64, 295 Belted Falsehorn 96, 379 Big-ankled Spikeleg 42, 289 Big-thighed Pithead 40, 281 Bistort Blacklet 46, 235 Black-ankled Stripeback 88, 349 Black-footed Bristleside 72, 131 Black-footed Globetail 76, 78, 169 Black-haired Whitebelt 68, 145 Black Halfband 58, 80, 82, 119 Black-horned Smoothtail 70, 149 Black-kneed Fen Fly 34, 325 Black Lagoon Fly 90, 341 Black-legged Blacklet 46, 233 Black-margined Marsh Fly 88, 353 Black-mouthed Smoothtail 72, 153 Black-spotted Brusheye 74, 141 Black-thighed Flower Fly 72, 129 Blackspine Sedgesitter 58, 62, 191 Blackthorn Sedgesitter 54, 60, 207 Bleached Falsehorn 96, 379 Blera fallax 96, 375 Blotch-winged Whitebelt 68, 145 Blue Blacklet 52, 259 Blue Wrinklehead 38, 311 Bog Ant Fly 26, 28, 107 Bog-dwelling Drone Fly 90, 341 Bog Globetail 76, 78, 171 Bogbean Swamp Fly 88, 345 Bolete Blacklet 44, 231 Bow-veined Aphideater 70, 159 Brachyopa bicolor 66, 297 bimaculosa 301 dorsata 64, 295 grunewaldensis 66, 299 insensilis 66, 299 obscura 64, 295 panzeri 64, 295 pilosa 66, 297 scutellaris 66, 297 silviae 66, 301 testacea 64, 66, 293 vittata 64, 293 Brachypalpoides lentus 100, 389

Brachypalpus laphriformis 94, 385 valgus 94, 385 Brassy Blacklet 46, 237 Broad-banded Aphideater 82, 84, 161 Broad-banded Fen Fly 34, 325 Broad-banded Globetail 76, 78, 167 Broad-barred Brusheye 74, 139 Broad-faced Pithead 40, 279 Broad-faced Smoothtail 72, 153 Broad-faced Wrinklehead 38, 309 Broad Flatface 42, 273 Broad-fronted Sedgesitter 56, 60, 209 Broadleaf Twinspot Sapeater 66, 301 Broken-banded Meadow Fly 26, 113 Buff-tailed Bumblefly 94, 381 Bulbous Buttercup Blacklet 46, 48, 245 Bumble Mimic 86, 343 Bumblebee Blacklet 48, 229 Bumblebee Plumehorn 28, 371 Bumblebee Pond Fly 94, 355 Butterbur Fen Fly 32, 327 Buttercup Blacklet 46, 48, 245 Cabbage Thistle Blacklet 50, 253 Caliprobola speciosa 4, 96, 375 Callicera aenea 28, 221 aurata 28, 221 fagesii 26, 219 macquarti 26, 219 rufa 26, 219 spinolae 28, 221 Carr Drone Fly 92, 335 Ceriana conopsoides 24, 223 vespiformis 24, 223 Chalcosyrphus curvipes 387 eunotus 94, 387 femoratus 100, 387 nemorum 100, 389 piger 100, 389 valgus 100, 387 Chalk Ant Fly 26, 28, 105 Chalk Wrinklehead 38, 307 Chamaesyrphus caledonicus 271 lugubris 271 scaevoides 271 Cheilosia aerea 52, 261 ahenea 46, 237 albipila 50, 249 albitarsis 46, 48, 245 antiqua 46, 233 barbata 48, 243 bergenstammi 52, 255 caerulescens 44, 239 canicularis 50, 251 carbonaria 50, 52, 259 chloris 50, 253 chrysocoma 50, 229 clama 44, 50, 253 cynocephala 52, 259 fasciata 48, 225 flavipes 44, 50, 249 fraterna 50, 52, 255 frontalis 48, 243 gigantea 52, 263 griseiventris 44, 48, 239 grisella 46, 237 grossa 50, 249 himantopus 50, 251

illustrata 48, 229 impressa 48, 245 lasiopa 48, 241 laticornis 44, 229 latifrons 44, 48, 239 lenis 50, 247 longula 44, 231 luteicornis 50, 227 morio 48, 50, 227 mutabilis 44, 52, 247 nebulosa 50, 253 nigripes 46, 233 orthotricha 50, 251 pagana 46, 241 proxima 52, 263 psilophthalma 52, 257 pubera 46, 237 ranunculi 46, 48, 245 rotundiventris 259 ruffipes 44, 231 ruficollis 259 rufimana 52, 265 sahlbergi 46, 235 scanica 227 scutellata 44, 231 semifasciata 48, 52, 225 soror 231 urbana 52, 257 uviformis 46, 52, 261 variabilis 48, 241 velutina 52, 265 vernalis 52, 259 vicina 46, 235 vulpina 48, 243 Chinless Blacklet 52, 265 Chrysogaster basalis 38, 311 cemiteriorum 38, 311 coerulea 311 rondanii 38, 309 solstitialis 38, 309 virescens 38, 309 Chrysotoxum arcuatum 26, 109 bicinctum 24, 111 cautum 24, 109 elegans 26, 113 fasciolatum 26, 109 festivum 24, 111 intermedium 107 lessonae 26, 107 octomaculatum 26, 113 vernale 24, 111 verralli 26, 113 Clubrush Fly 88, 347 Comb-legged Sedgesitter 58, 62, 191 Common Batman Fly 86, 343 Common Bighorn Fly 54, 273 Common Compost Fly 98, 397 Common Dainty 30, 211 Common Drone Fly 90, 329 Common Flatface 42, 44, 275 Common Flower Fly 72, 129 Common Globetail 76, 78, 167 Common Grass Skimmer 30, 213 Common Lagoon Fly 90, 341 Common Pithead 42, 283 Common Pufftail 32, 319 Common Sedgesitter 58, 62, 185 Common Snout Fly 64, 269 Common Spotted Bristleside 74, 133 Common Wasp Fly 24, 223 Common Wrinklehead 38, 305 Conifer Sapeater 64, 66, 293

Conifer Twinspot Sapeater 301 Constricted Grass Skimmer 30, 213 Crimson-belted Leafwalker 100, 389 Criorhina asilica 94, 383 berberina 381 floccosa 4, 94, 381 pachymera 94, 383 ranunculi 94, 383 Crossband Dayglower 66, 177 Curlyhair Sedgesitter 54, 60, 207 Daffodil Roundface 98, 361 Dark-backed Smoothtail 72, 149 Dark-clawed Blacklet 52, 257 Dark Duskyface 56, 60, 183 Dark-haired Smoothleg 42, 291 Dark-knobbed Lucent 68, 143 Dark-legged Bristleside 70, 135 Dark Longhorn 26, 219 Dark-saddled Hoary 30, 68, 147 Dark-saddled Sapeater 66, 297 Dark-shouldered Sapeater 66, 297 Dark Smoothtail 72, 151 Dark Spikeleg 42, 287 Dark Spineleg 34, 303 Dark-winged Wrinklehead 38, 309 Dark Wrinklehead 38, 305 Dasysyrphus albostriatus 72, 137 friuliensis 74, 137 hilaris 74, 139 lenensis 74, 141 neovenustus 74, 139 pauxillus 74, 141 pinastri 74, 141 tricinctus 74, 137 venustus 74, 139 Didea alneti 68, 143 fasciata 68, 143 intermedia 68, 143 Dimorphic Bumblefly 94, 381 Ditch Swamp Fly 88, 345 Doros profuges 66, 177 Dry Flatface 42, 277 Dull-backed Sedgesitter 56, 62, 205 Dull-bellied Blacklet 52, 263 Dune Bighorn Fly 54, 271 Dusky Falsehorn 96, 381 Dusky Sedgesitter 58, 62, 185 Dusted Blacklet 46, 237 Dusted Drone Fly 92, 337 Early Butterbur Blacklet 50, 251 Eastern Globetail 76, 78, 173 Elegant Pufftail 32, 319 Epistrophe cryptica 72, 151 diaphana 70, 151 eligans 74, 155 flava 72, 153 grossulariae 70, 149 leiophthalma 68, 155 melanostoma 72, 153 nitidicollis 72, 149 obscuripes 72, 151 ochrostoma 72, 153 olgae 72, 149 Epistrophella euchroma 80, 155 Episyrphus balteatus 72, 115 Eriozona annulipes 145 syrphoides 66, 147 Eristalinus aeneus 90, 341 sepulchralis 90, 341

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Eristalis abusiva 90, 331 alpina 92, 337 anthophorina 90, 339 arbustorum 90, 331 cryptarum 90, 341 horticola 92, 333 interrupta 331 interruptus 331 intricaria 90, 339 jugorum 92, 333 nemorum 90, 331 obscura 335 oestracea 90, 339 pertinax 90, 329 picea 92, 335 pratorum 329 pseudorupium 92, 335 rupium 92, 337 similis 90, 329 tenax 90, 329 Eumerus amoenus 98, 363 flavitarsis 98, 363 funeralis 98, 361 narcissi 98, 361 ornatus 98, 363 ruficornis 98, 361 sabulonum 98, 365 sogdianus 98, 359 strigatus 98, 359 tarsalis 98, 365 tricolor 96, 365 Eupeodes bucculatus 84, 165 corollae 82, 84, 161 goeldlini 84, 165 lapponicus 159 latifasciatus 82, 84, 161 lundbecki 82, 84, 159 luniger 84, 163 nielseni 84, 163 nitens 84, 161 Eurasian Copperback 96, 267 Eurasian Drone Fly 90, 331 Eurasian Pocota 94, 385 Eurimyia lineata 88, 345 Fagisyrphus cinctus 80, 127 Ferdinandea cuprea 96, 267 ruficornis 96, 267 Figwort Blacklet 48, 241 Fivespot Hornet Fly 96, 377 Flaming Grass Skimmer 30, 217 Forest Sapeater 66, 299 Forest Snout Fly 64, 269 Four-spotted Pithead 40, 279 Fourspot Sedgesitter 54, 209 Foxy Blacklet 50, 229 Fragile Blacklet 44, 52, 247 Fragile Sedgesitter 56, 62, 203 Furry Drone Fly 90, 339 Furry Pond Fly 94, 355 Garlic Blacklet 48, 225 Glass-winged Drone Fly 90, 329 Goatsbeard Roundface 96, 365 Goeldlin’s Aphideater 84, 165 Gold-spotted Smoothtail 80, 155 Golden Bulb Fly 86, 369 Golden Longhorn 28, 221 Golden-tailed Leafwalker 100, 393 Golf-club Swamp Fly 88, 347 Great Banded Gossammer 68, 145 Greater Dull-bellied Blacklet 52, 263 Greater Forest Fly 94, 385 Greater Meadow Fly 26, 109 Greater Orange-thighed Leafwalker 100, 387 Greater Sapeater 64, 293

Greater Spotted Bristleside 74, 133 Greater Spring Blacklet 50, 249 Green Lucent 68, 143 Green Shimmer 36, 313 Green Wrinklehead 38, 309 Grey-banded Grass Skimmer 30, 215 Grey-spotted Sedgesitter 56, 60, 195 Hairy-eyed Flower Fly 72, 127 Hairy Hornet Fly 96, 377 Hairy-legged Flatface 42, 44, 275 Hairy Thickleg 86, 98, 397 Hammerschmidtia ferruginea 64, 293 Hawkbit Blacklet 44, 48, 239 Heath Ant Fly 26, 28, 105 Heath Blacklet 44, 231 Heath Globetail 76, 78, 171 Heathland Grass Skimmer 30, 213 Helophilus affinis 88, 353 groenlandicus 88, 353 hybridus 88, 351 pendulus 88, 351 trivittatus 4, 88, 351 Heringia heringi 42, 291 senilis 291 Hidden Blacklet 44, 50, 253 Hidden Wrinklehead 38, 307 Hook-banded Brusheye 74, 137 Hook-banded Meadow Fly 24, 111 Hornet Giant 96, 375 Hornet Plumehorn 28, 371 Hornhand Sedgesitter 54, 211 Houseleek Blacklet 44, 239 Intermediate Duskyface 56, 60, 183 Interrupted Globetail 76, 171 Ivy Longhorn 28, 221 Jewel Wood Fly 96, 375 Kingcup Blacklet 48, 243 Knotweed Blacklet 52, 265 Lady’s-mantle Blacklet 46, 235 Lapposyrphus lapponicus 70, 159 Large Ant Fly 26, 28, 105 Large Bumblefly 94, 383 Large-horned Blacklet 44, 229 Large Meadow Fly 24, 109 Large-spotted Psyllid-killer 40, 285 Large-spotted Smoothwing 70, 159 Leafmining Blacklet 48, 52, 225 Lejogaster metallina 36, 313 tarsata 36, 313 Lejops vittatus 88, 347 Lemon Marsh Fly 88, 351 Lena’s Brusheye 74, 141 Lesser Brusheye 74, 141 Lesser Orange-thighed Leafwalker 100, 387 Lesser Pufftail 32, 321 Lesser Roundface 98, 361 Lesser Spring Blacklet 50, 249 Leucozona glaucia 4, 68, 147 inopinata 68, 145 laternaria 30, 68, 147 lucorum 68, 145 Levels Drone Fly 90, 331 Limestone Ant Fly 26, 28, 107 Little Meadow Fly 26, 109 Little Pithead 42, 283 Logjammer 94, 387

Long-horned Smoothleg 291 Long Sedgesitter 58, 62, 187 Long-winged Duskyface 56, 60, 181 Lunuled Aphideater 84, 163 Macquart’s Longhorn 26, 219 Mallota cimbiciformis 86, 343 fuciformis 86, 343 Many-spotted Fen Fly 32, 323 Many-tufted Sedgesitter 56, 60, 197 Marmalade Hoverfly 72, 115 Marsh Stripeback 88, 349 Matsumyia berberina 94, 381 Matt-backed Halfband 80, 82, 123 Mealy Sapeater 66, 299 Megasyrphus erraticus 68, 145, 159 Melangyna arctica 80, 82, 123 barbifrons 80, 82, 119 cincta 127 compositarum 80, 82, 123 ericarum 80, 82, 123 labiatarum 123 lasiophthalma 82, 121 lucifera 82, 125 pavlovskyi 80, 82, 125 quadrimaculata 22, 58, 80, 82, 119 umbellatarum 80, 82, 121 Melanogaster aerosa 38, 305 curvistylus 38, 307 hirtella 38, 305 nuda 38, 303 parumplicata 38, 307 Melanostoma certum 56, 60, 183 dubium 183 mellarium 56, 60, 183 mellinum 56, 60, 181 scalare 56, 60, 181 Meligramma cingulata 54, 80, 117 guttata 80, 117 triangulifera 80, 117 Meliscaeva auricollis 80, 115 cinctella 80, 115 Merodon aeneus 369 armipes 367 aureus 86, 369 avidus 367 equestris 86, 369 moenium 86, 367 ruficornis 86, 367 rufus 86, 367 Microdon analis 26, 28, 105 devius 26, 28, 105 major 26, 28, 105 mutabilis 26, 28, 107 myrmicae 4, 26, 28, 107 Migrant Aphideater 82, 84, 161 Migrant Flatbelly 54, 211 Migrant Marsh Fly 88, 353 Milesia crabroniformis 96, 375 Mire Mucksucker 36, 317 Moon Falsehorn 96, 379 Mugwort Galleater 40, 273 Mullein Blacklet 52, 261 Myathropa florea 86, 343 Myolepta dubia 34, 301 obscura 34, 303 potens 34, 301 vara 34, 303 Naked Meadow Fly 26, 107 Naked Wrinklehead 38, 303 Narcissus Bulb Fly 86, 369 Narrow-banded Aphideater 84, 165 Narrow-barred Brusheye 74, 139

Needle Roundtail 54, 80, 117 Needle Sedgesitter 54, 60, 207 Neoascia annexa 34, 325 geniculata 32, 323 interrupta 32, 323 meticulosa 32, 325 obliqua 32, 327 podagrica 32, 327 tenur 34, 325 unifasciata 32, 327 Neocnemodon brevidens 42, 291 latitarsis 42, 289 pubescens 42, 287 verrucula 42, 287 vitripennis 42, 289 Nielsen’s Sedgesitter 58, 62, 201 Nordic Mucksucker 36, 315 Northern Bee Mimic 86, 343 Northern Broadhand Sedgesitter 58, 60, 203 Northern Saprun Wasp Fly 24, 223 Obscure Psyllid-killer 40, 285 Obscure Spineleg 34, 303 Olbiosyrphus laetus 177 Olga’s Smoothtail 72, 149 Onion Roundface 98, 359 Orange-belted Leafwalker 100, 395 Orange-belted Plumehorn 28, 373 Orange-belted Spineleg 34, 301 Orange-horned Copperback 96, 267 Orange-horned Roundface 98, 363 Orange-legged Sedgesitter 58, 62, 193 Orange-shinned Blacklet 50, 52, 255 Orange Snout Fly 64, 269 Orange-spotted Bighorn Fly 54, 271 Orange-spotted Drone Fly 90, 339 Orange-tailed Drone Fly 90, 339 Orthonevra arcana 315 brevicornis 36, 315 elegans 36, 313 erythrogona 36, 315 geniculata 36, 317 intermedia 36, 317 nobilis 36, 315 stackelbergi 36, 317 Pale-clawed Blacklet 52, 257 Pale-footed Pithead 40, 279 Pale-footed Psyllid-killer 40, 285 Pale-haired Spikeleg 42, 289 Pale-knobbed Lucent 68, 143 Pale-legged Flatface 42, 44, 275 Pale-saddled Hoary 68, 147 Pale Sapeater 64, 295 Pale-shouldered Sapeater 66, 297 Pale-sided Smoothtail 70, 151 Paragus albifrons 30, 215 constrictus 30, 213 finitimus 30, 217 flammeus 30, 217 haemorrhous 4, 30, 213 pecchiolii 30, 215 quadrifasciatus 30, 70, 217 testaceus 30, 215 tibialis 30, 213 Parasyrphus annulatus 70, 133 lineola 70, 135 macularis 74, 133 malinellus 70, 131 nigritarsis 72, 131 punctulatus 74, 133 relictus 70, 135 vittiger 135

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Parhelophilus consimilis 88, 349 frutetorum 88, 349 versicolor 88, 349 Parsley Blacklet 46, 241 Parsnip Blacklet 48, 243 Peg-footed Roundface 98, 365 Pelecocera caledonica 54, 271 lugubris 54, 271 lusitanica 271 scaevoides 54, 271 tricincta 54, 273 Phantom Potterfly 66, 177 Pied Plumehorn 28, 373 Pine Bristleside 70, 135 Pine Haireye 34, 357 Pine Hoverfly 96, 375 Pine Longhorn 26, 219 Pinewood Aphideater 84, 163 Pinewood Globetail 76, 78, 169 Pinewood Halfband 80, 82, 123 Pipiza accola 40, 279 austriaca 40, 281 bimaculata 283 fasciata 40, 281 fenestrata 281 festiva 40, 281 lugubris 40, 283 luteibarba 279 luteitarsis 40, 279 noctiluca 42, 283 notata 42, 283 quadrimaculata 40, 279 Pipizella annulata 42, 44, 275 divicoi 42, 273 maculipennis 42, 44, 277 pennina 42, 277 viduata 42, 44, 275 virens 42, 44, 275 zeneggenensis 42, 277 Plantain Blacklet 48, 241 Platycheirus albimanus 56, 60, 195 ambiguus 54, 60, 207 amplus 58, 60, 203 angustatus 58, 62, 187 aurolateralis 56, 60, 199 clypeatus 58, 62, 185 complicatus 56, 62, 203 discimanus 56, 60, 209 europaeus 58, 62, 187 fulviventris 58, 62, 193 granditarsus 211 immaculatus 54, 60, 207 immarginatus 58, 62, 191 manicatus 56, 62, 205 melanopsis 56, 62, 209 nielseni 58, 62, 201 occultus 58, 62, 185 parmatus 58, 60, 199 peltatus 58, 62, 201 perpallidus 58, 62, 193 podagratus 58, 62, 189 ramsarensis 58, 62, 189 scambus 58, 62, 191 scutatus 56, 60, 197 splendidus 56, 60, 197 sticticus 56, 60, 195 tarsalis 56, 62, 205 transfugus 54, 60, 207 Pocota personata 94, 385 Poplar Bumblefly 94, 383 Poplar Pithead 40, 281 Poplar Spikeleg 42, 291 Portevinia maculata 46, 225 Primrose Blacklet 46, 233 Psarus abdominalis 26, 267 Psilota anthracina 34, 357 atra 34, 357

exilistyla 34, 357 Pyrophaena granditarsa 54, 211 rosarum 54, 209 Ragwort Blacklet 52, 255 Red-belted Leafwalker 100, 395 Red-dotted Grass Skimmer 30, 215 Red Grass Skimmer 30, 215 Red-horned Pufftail 32, 321 Red-tailed Leafwalker 100, 389 Rhingia borealis 64, 269 campestris 64, 269 rostrata 64, 269 Ringed Beech Fly 80, 127 Riponnensia splendens 36, 311 Rueppell’s Globetail 76, 175 Sakhalin Halfband 80, 82, 125 Saltmarsh Globetail 76, 175 Scaeva albomaculata 70, 159 dignota 70, 157 mecogramma 159 pyrastri 70, 157 selenitica 70, 157 Sericomyia bombiformis 94, 100, 355 lappona 94, 355 silentis 94, 353 superbiens 94, 355 Sheep’s-bit Roundface 98, 365 Shiny-backed Halfband 80, 82, 121 Shiny-backed Sedgesitter 56, 62, 205 Shiny Pufftail 32, 323 Short-horned Fen Fly 32, 323 Silver-footed Roundface 98, 363 Silver-fronted Blacklet 46, 52, 261 Silver Halfband 82, 125 Silver-spotted Bighorn Fly 54, 271 Single-banded Fen Fly 32, 327 Slender-handed Sedgesitter 56, 60, 195 Slender Roundface 98, 359 Slender Sedgesitter 58, 62, 187 Slim-horned Mucksucker 36, 315 Slim-tailed Leafwalker 100, 393 Small Leafwalker 100, 389 Small-spotted Sedgesitter 56, 60, 199 Small-spotted Spineleg 34, 301 Smallpit Sapeater 64, 295 Smoky-winged Dayglower 68, 179 Smoky-winged Leafwalker 100, 391 Smooth-banded Meadow Fly 24, 111 Smooth-winged Aphideater 82, 84, 159 Smudge-faced Bristleside 70, 131 Smudge-veined Fen Fly 32, 327 Smudge-winged Blacklet 50, 253 Smudge-winged Flatface 42, 44, 277 Smudge-winged Pithead 40, 283 Snouted Drone Fly 92, 333 Snouted Duck Fly 88, 345 Sooty Blacklet 50, 52, 259 Southern Smoothwing 70, 157 Southern Wasp Fly 24, 223 Sow-thistle Blacklet 44, 48, 239 Sphaerophoria bankowskae 76, 78, 173 batava 76, 78, 169 chongjini 76, 78, 173 fatarum 76, 78, 171

interrupta 76, 171 loewi 76, 175 philanthus 76, 78, 169 potentillae 76, 78, 173 rueppelli 76, 175 scripta 4, 76, 78, 167 shirchan 76, 175 taeniata 76, 78, 167 virgata 76, 78, 171 Sphegina clavata 321 clunipes 32, 319 elegans 32, 319 montana 32, 323 nigra 32, 321 sibirica 32, 319 spheginea 32, 321 verecunda 32, 321 Sphiximorpha subsessilis 24, 223 Spilomyia manicata 96, 377 saltuum 96, 377 Spindly Haireye 34, 357 Spine-legged Bulb Fly 86, 367 Spiny Grass Skimmer 30, 217 Splendid Sedgesitter 56, 60, 197 Splendid Shimmer 36, 313 Spot-winged Drone Fly 92, 337 Spotted Garlic Eater 46, 225 Spotted Roundtail 80, 117 Spotted Thintail 80, 115 Spring Butterbur Blacklet 50, 251 Spring Drone Fly 92, 335 Spring Halfband 82, 121 Spring Smoothtail 74, 155 Spruce Blacklet 50, 227 Spruce-stump Leafwalker 100, 391 Square-spot Pithead 40, 281 Stackelberg’s Dayglower 68, 179 Stackelberg’s Mucksucker 36, 317 Stocky Blacklet 48, 243 Stocky Pufftail 32, 321 Stocky Sedgesitter 56, 62, 209 Stripe-backed Brusheye 72, 137 Stripe-backed Glimmer 36, 311 Stripe-eyed Mucksucker 36, 313 Stripe-faced Drone Fly 90, 331 Stripe-faced Globetail 76, 175 Stripe-winged Drone Fly 92, 333 Summer Butterbur Blacklet 50, 251 Superb Dayglower 66, 179 Swamp Thickleg 98, 397 Syritta pipiens 98, 397 Syrphus nitidifrons 74, 127 rectus 129 ribesii 72, 129 torvus 72, 127 vitripennis 72, 129 Tapered Bulb Fly 86, 367 Tapered Drone Fly 90, 329 Temnostoma apiforme 96, 379 bombylans 96, 381 meridionale 96, 379 sericomyiaeforme 96, 379 vespiforme 96, 377 Thick-thighed Forest Fly 94, 385 Tiger Marsh Fly 88, 351 Tormentil Globetail 76, 78, 173 Triangle-spotted Roundtail 80, 117 Trichopsomyia flavitarsis 40, 285 joratensis 40, 285 lucida 40, 285 Triglyphus primus 40, 273 Tropidia fasciata 86, 98, 397 scita 98, 397 Truffle Blacklet 44, 231

Tubercled Flatface 42, 277 Tuberculate Stripeback 88, 349 Two-banded Meadow Fly 24, 111 Uniform Bulb Fly 86, 367 Variable Duskyface 56, 60, 181 Variable Meadow Fly 26, 113 Variable Pufftail 32, 319 Variable Sedgesitter 58, 62, 189 Vermillion Fly 26, 267 Verrall’s Meadow Fly 26, 113 Viper’s-grass Roundface 98, 361 Volucella bombylans 28, 371 inanis 28, 373 inflata 28, 373 pellucens 28, 373 zonaria 28, 371 Waisted Swamp Fly 88, 347 Warted Spikeleg 42, 287 Wasp Falsehorn 96, 377 Wasp Plumehorn 28, 373 Water Avens Blacklet 46, 237 Wavy-banded Aphideater 84, 161 Wavy-banded Smoothtail 72, 151 White-barred Pond Fly 94, 355 White-bowed Smoothwing 70, 157 White-spotted Sedgesitter 58, 62, 201 Whitebelt Smoothtail 68, 155 Willow Mucksucker 36, 317 Wood Blacklet 50, 247 Wood Sedgesitter 58, 60, 199 Woodland Roundface 98, 363 Woolly-tailed Marsh Fly 88, 351

Xanthandrus comtus 54, 211 Xanthogramma citrofasciatum 66, 177 dives 68, 179 laetum 66, 177 pedissequum 4, 66, 179 stackelbergi 68, 179 Xylota abiens 100, 391 florum 100, 393 ignava 100, 395 jakutorum 100, 391 meigeniana 100, 391 segnis 100, 395 sylvarum 100, 393 tarda 100, 395 xanthocnema 100, 393 Yarrow Blacklet 52, 259 Yellow-banded Grass Skimmer 30, 70, 217 Yellow-barred Pond Fly 94, 353 Yellow-bowed Smoothwing 70, 157 Yellow-faced Brusheye 74, 139 Yellow-footed Bristleside 70, 133 Yellow-girdled Brusheye 74, 137 Yellow-kneed Fen Fly 32, 325 Yellow-legged Blacklet 44, 50, 249 Yellow Longhorn 28, 221 Yellow-mouthed Smoothtail 72, 153 Yellow-shinned Leafwalker 100, 393 Yellow-winged Blacklet 48, 245 Yellow-winged Wrinklehead 38, 311 Yellowcomb Sedgesitter 58, 62, 193

4 00 ⁞ HOVERF LI ES O F BR ITAIN AND NORTH-WE ST E U ROPE

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