Monogenetic Trematodes of Hawaiian Fishes 9780824885441

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Monogenetic Trematodes of Hawaiian Fishes

Monogenetic Satyu

Yamaguti

Trematodes of Hawaiian Fishes U N I V E R S I T Y OF HAWAII PRESS

HONOLULU

1968

Copyright iç68 by the University of Hawaii Press Library of Congress Catalog Card Number 67-19986 Hawaii Institute of Marine Biology Contribution No. 262 Designed by James C. Wageman Manufactured in the United States of America

Preface

Of the platyhelminthes from Hawaiian fishes only the digenetic trematodes have been investigated, by Dr. W. E. Martin, Dr. H. W. Manter, and Mrs. M. H. Pritchard. No monogenetic trematodes have been reported so far from fishes in Hawaiian waters, although numerous species are known from West Pacific and Australian waters (Goto, Yamaguti, Johnston and Tiegs, etc.), and a few from Fiji and New Zealand (Manter et al., Robinson, Dillon and Hargis) and the East Pacific (Caballero et al.). Under these circumstances I have attempted to carry out an extensive survey of helminth parasites, especially trematodes, assisted by Mr. Shunya Kamegai and Mrs. S. Yamaguti, with the aid of an extended grant (GB-78, GB-2992 and GB-4480) from the National Science Foundation, under the sponsorship of the University of Hawaii. I offer many thanks to these organizations and individuals. At the termination of the grant, 280 species of fish have been examined, and 30 new genera and 131 new species of Monogenea have been found, in addition to those species reported in Pacific Science (1965, 1966). Many other fishes have escaped our examination, however, and some species have not been described owing to lack of material, so that my survey is by no means complete. I hope my successors will be able to fill the gaps in my survey. SATYU YAMAGUTI

Hawaii Institute of Marine Biology University of Hawaii July 1966

Contents

1 2 3 4 5

Introduction 11 List of Monogenea collected 14 Description and discussion of species Host-parasite list 194 Summary 199 Plates 201 References 281 Index 285

19

Monogenetic Trematodes of Hawaiian Fishes

1 | Introduction

This monograph is based on the collections made by Mr. Shunya Kamegai, my assistant, from marine fishes purchased at the Honolulu fish market and, on occasion, from fishes supplied by the Waikiki Aquarium, University of Hawaii. T h e fishes examined for parasites were identified by Professor W . A. Gosline, Department of Zoology, University of Hawaii. Effort was made to secure as wide a variety of fishes as possible but, because the majority of elasmobranch fishes are not available at the Honolulu fish market, the species of fishes examined by us during a four-year period did not amount to half the total number known to occur in Hawaiian waters (approximately 600 species and 139 families, according to Gosline and Brock, i960). T h e trematodes collected were fixed immediately in acetic Schaudinn's solution under cover-glass pressure, with or without the aid of a wire compressorium. Small monogenetic trematodes found in the washings of the skin and gill lamellae, from which the parasites had been liberated spontaneously, were picked up by a fine pipette; others which were firmly attached to the host were removed with a Japanese hair brush or a dissecting lancet or needle under a low-power binocular microscope. Small worms, such as Ancyrocephalus or Haliotrema, are usually difficult to detect with the naked eye alone. Large Monogenea are easy to detect, of course, and to collect. PREPARATION OF WHOLE MOUNTS

Of the small specimens, if many were available, all were pipetted together on a slide with a small amount of saline solution and were examined for eggs, the natural shape and size of which were checked and measured in life whenever possible. In order to fix small Monogenea, like most ancyrocephaline species, a special technique was employed. If they were fresh enough and available in large numbers, all of them were transferred by a fine pipette to a slide and, after removing excess saline with a very fine pipette or blotting paper, they were left there until they became half dry. (This procedure is necessary in order to keep the specimens firmly attached to the slide during further handling of the slide.) Then the specimens were covered with a cover-glass, the surface of which had been moistened with a few drops of acetic Schaudinn's solution. The size of the cover-glass used varied according to the degree of freshness of the specimens. If the cover-glass is too large or the amount of the fixative is too little for the material, the pressure of the cover-glass alone may damage the worms. If the material is large and fresh or unusually thick,

12

it must be subjected to strong cover-glass pressure by a wire compressorium. Usually it is necessary to drop fresh fixative beneath one end of the cover-glass and to drain the fluid away slowly from the specimen, using a piece of heavy blotting paper at the opposite end of the coverglass. This method permits frequent addition of fresh fixative to come constantly in contact with the specimen. After proper fixation the worm should appear uniformly opaque. Sometimes it is necessary to raise one end of the cover-glass gently from the slide after adding fresh fixative at that end. Material which is not fresh or is already decomposing is of no use, because it cannot be properly stained with any dyes; only the eggs, if they are present, can be used for measurements and observations upon their structure. The slide on which the worm is mounted in the fixative under a coverglass is left overnight in a covered square plastic dish, which is placed under a large glass dish turned upside down on a glass plate, to prevent desiccation. Release of the cover-glass is made on the next morning with utmost care. I have found the best way to do this is to soak the slide gently in water and to wait until the cover-glass is loosened from the slide. Another method is to raise the cover-glass slowly in water by inserting the point of the finest Japanese drawing-brush under one edge of the cover-glass while the opposite edge is held down with a finger tip. Fixation under a cover-glass alone is usually inadequate, so that continued treatment of the specimen in a sufficient quantity of the fixative is recommended after the cover-glass has been released from the slide. When the cover-glass is released from the slide, the worms usually remain entirely or partly attached to either the cover-glass or the slide, or they may be completely detached, especially when the worm is thick. In any event, whether the worm remains attached or detached, it should be subjected to further fixation. If the specimen is only partially adhering to the slide or cover-glass, a thin film of collodion dissolved in alcohol-ether may be used to cover the specimen in order to prevent its detachment during further manipulation. This technique is very useful for worms which are small and delicate. For most specimens of average size further fixation does not require more than three hours, but thicker specimens will need a longer time. After complete fixation the sublimate in the tissue of the worm must be removed by iodine alcohol, as in the routine procedure. To stain such specimens fixed in acetic Schaudinn's solution, only Heidenhain's hematoxylin was used after the worms had been treated with 2.5% ferric ammonium sulfate. If the specimens stained with this hematoxylin cannot be bleached adequately with ferric ammonium sulfate, then they should be treated with 1 % oxalic acid for a few minutes (or longer if necessary) until the whole worm becomes bleached properly. (For further details about techniques of dehydration and mounting in balsam, see my article "Preparation of Stained Whole Mounts of Flatworms," in Transactions of the American Microscopical Society, 84(4): 602-603.)

introduction

DISPOSITION OF T Y P E SPECIMENS

13

The holotypes of all new species are deposited in the Helminthological Collection of the United States National Museum at the Beltsville Parasitological Laboratory, Beltsville, Maryland, and most of the paratypes and most of the specimens of already-named species are in the Yamaguti Collection of the Meguro Parasitological Museum in Tokyo, Japan. The remaining specimens are in the helminthological collection of the University of Hawaii.

2|

Order Superfamily Family Subfamily

Subfamily

Subfamily Family Subfamily Family Subfamily

List of Monogenea collected

M O N O P I S T H O C O T Y L E A Odhner, 1912 CAPSALOIDEA Price, 1936 CAPSALIDAE Baird, 1853 BENEDENIINAE Johnston, 1931 1 Benedenia bodiani n. sp. 2 Benedenia hawaiiensis n. sp. 3 Benedenia lolo n. sp. 4 Benedenia scari n. sp. 5 Pseudobenedenia elongata n. sp. 6 Pseudobenedenia merinthe n. sp. 7 Pseudobenedenia ovalis n. sp. 8 Allobenedenia epinepheli n. sp. 9 Pseudallobenedenia apharei Yamaguti, 1966 10 Pseudallobenedenia opakapaka Yamaguti, 1966 11 Lagenivaginopseudobenedenia etelis Yamaguti, 1966 12 Dioncopseudobenedenia kala Yamaguti, 1965 Dioncopseudobenedenia macracanihd 11. sp. Oligoncobenedenia nasonis Yamaguti, 1965 M CAPSALINAE Johnston, 1929 15 Capsala gotoi n. sp. 16 Capsala neothunni n. sp. *7 Capsala nozawae (Goto, 1894) 18 Capsala ovalis (Goto, 1894) Capsala (Caballerocotyla) biparasitica (Goto, 1894) 20 Capsaloides cristatus n. sp. 21 Capsaloides istiophori n. sp. 22 Capsaloides nairagi n. sp. 23 Capsaloides sinuatus (Goto, 1894) 2 4 Capsaloides tetrapteri n. sp. 2 5 Tristoma adcoccineum n. sp. 26 Tristoma adintegrum n. sp. 2 7 Nasicola klawei (Stunkard, 1962) n. comb. Johnston, 1931 28 Pseudonitzschia uku Yamaguti, 1965 MICROBOTHRIIDAE Price, 1936 ENOPLOCOTYLINAE Tagliani, 1912 29 Enoplocotyle hawaiiensis n. sp. M O N O C O T Y L I D A E Taschenberg, 1879 MONOCOTYLINAE Gamble, 1896 30 Diploheterocotyla dasyatis Yamaguti, 1965 31 Alloheterocotyla aetobatis (Hargis, 1955) n. comb. NITZSCHIINAE

List of Monogenen

Superfamily Family Subfamily

D A C T Y L O G Y R O I D E A Yamaguti, 1963 D A C T Y L O G Y R I D A E Bychowsky, 1933 ANCYROCEPHALINAE Bychowsky, 1937 32 Ancyrocephalus ornatus n. sp. 33 Ancyrocephalus parupenei n. sp. 34 Ancyrocephalus pauu n. sp. 35 Haliotrema acanthuri n. sp. 36 Haliotrema amanses n. sp. 37 Haliotrema angulare n. sp. 38 Haliotrema angulocirrus n. sp. 39 Haliotrema annulocirrus n. sp. 40 Haliotrema bifurcocirrus n. sp. 41 Haliotrema bisegmentatum n. sp. 42 Haliotrema bodiani n. sp. 43 Haliotrema brotulae n. sp. 44 Haliotrema caesiopercae n. sp. 45 Haliotrema canescens n. sp. 46 Haliotrema centropygis n. sp 47 Haliotrema chelicirrus n. sp. 48 Haliotrema chromidis n. sp. 49 Haliotrema ctenochaeti n. sp. 50 Haliotrema curvicirrus n. sp. 51 Haliotrema epinepheli n. sp 52 Haliotrema flagellatum n. sp. 53 Haliotrema flexicirrus n. sp. 54 Haliotrema lactoriae n. sp. 55 Haliotrema macracantha n. sp. 56 Haliotrema microphallus n. sp. 57 Haliotrema minutospirale n. sp. 58 Haliotrema palmatum n. sp. 59 Haliotrema pervagoris n. sp. 60 Haliotrema priacanthi n. sp. 61 Haliotrema pterophallus n. sp. 62 Haliotrema rectangulare n. sp. 63 Haliotrema scyphovagina n. sp. 64 Haliotrema serpenticirrus n. sp. 65 Haliotrema sigmoidocirrus n. sp. 66 Haliotrema spiculare n. sp. 67 Haliotrema spirale n. sp. 68 Haliotrema tubulovagina n. sp. 69 Haliotrema zancli n. sp. 70 Cleithrarticus bulbovagina n. sp. 71 Cleithrarticus cleithrarticus Mizelle, 1963 72 Pseudancyrocephalus kala n. g., n. sp. 73 Pseudancyrocephalus duplicatus n. sp. 74 Pseudancyrocephalus longicirrus n. sp.

15

i6

75 76 77 78 79 80 81 82 83 84 85 86 Family

Order Superfamily Family Subfamily Family Subfamily Subfamily Family Subfamily Subfamily

Subfamily Subfamily

Pseudancyrocephalus longispicularis n. sp. Pseudancyrocephalus nasonis n. sp. Neohaliotrema maomao Yamaguti, 1965 Pseudohaliotrematoides aurigae n. sp. Pseudohaliotrematoides falcatus n. sp. Pseudohaliotrematoides microphallus n. sp. Pseudohaliotrematoides recurvatus n. sp. Pseudohaliotrematoides triangulovagina n. sp. Pseudohaliotrematoides zancli n. sp. Parancyrocephaloides dactylopteri n. sp. Murraytrematoides kuhliae n. sp. Pseudempleurosoma carangis Yamaguti, 1965

DIPLECTANIDAE Bychowsky, 1957 87 Nasobranchitrema pacificum Yamaguti, 1965 88 Diplectanum curvivagina n. sp. 89 Diplectanum diplobulbus n. sp. 90 Diplectanum kuhliae n. sp. 91 Diplectanum nenue n. sp. 92 Diplectanum opakapaka n. sp. 93 Diplectanum priacanthi n. sp. 94 Diplectanum querni n. sp. 95 Diplectanum spiculare n. sp. 96 hamellodiscus epsilon n. sp. 97 Acleotrema kyphosi n. sp. POLYOPISTHOCOTYLEA Odhner, 1912 DICLIDOPHOROIDEA Price, 1936 DICLIDOPHORIDAE Cerfontaine, 1895 G E M P Y L I T R E M A T I N A E n. subfam. 98 Gempylitrema longipedunculatum n. g., n. sp. PSEUDODICLIDOPHORIDAE Yamaguti, 1965 PSEUDODICLIDOPHORINAE Yamaguti, 1 9 6 5 99 Pseudodiclidophora decapteri Yamaguti, 1965 ALLOPSEUDODICLIDOPHORINAE Yamaguti, 1 9 6 5 100 Allopseudodiclidophora opelu Yamaguti, 1965 DISCOCOTYLIDAE Price, 1936 ALLODISCOCOTYLINAE Tripathi, 1 9 5 9 101 Allodiscocotyla lae n. sp. OPISTHOGYNINAE Unnithan, 1 9 6 2 X02 Pseudopisthogyne lepidocybii Yamaguti, 1965 103 Allopseudopisthogyne constrica Yamaguti, 1965 104 Metopisthogyne sphyraenae Yamaguti, 1966 105 Pseudopisthogynopsis lepidocybii Yamaguti, 1965 V A L L I S I I N A E Price, 1 9 4 3 106 Vallisiopsis sphyraenae n. sp. PSEUDODISCOCOTYLINAE Yamaguti, 1 9 6 5

List of Monogenea

Family

Family Subfamily Family Subfamily Subfamily Family Superfamily Family Subfamily

Subfamily

Subfamily Subfamily Subfamily Subfamily Family Family Subfamily

107 Pseudodiseocotyla opakapaka Yamaguti, 1965 HEXOSTOMATIDAE Price, 1936 108 Hexostoma keokeo n. sp. 109 Hexostoma sibi n. sp. n o Neohexostoma kawakawa n. sp. MAZOCRAEIDAE Price, 1936 MAZOCRAEINAE Price, 1961 1 1 1 Kuhnia scombri (Kuhn, 1829) PROTOMICROCOTYLIDAE Poche, 1926 PROTOMICROCOTYLINAE Johnston et Tiegs, 1922 112 Protomicrocotyle celebesensis Yamaguti, 1953 NEOMICROCOTYLINAE Ramalingam, i960 113 Neomicrocotyle carangis n. sp. PTERINOTREMATIDAE Bychowsky et Nagibina, 1959 114 Pseudopterinotrema albulae Yamaguti, 1966 MICROCOTYLOIDEA Unnithan, 1957 A X I N I D A E Unnithan, 1957 A X I N I N A E Monticelli, 1903 115 Axine belones Abildgaard, 1794 116 Axine depauperati n. sp. 117 Axine spilonotopteri n. sp. 118 Axinoides bulbosus n. sp. 119 Axinoides diploporus n. sp. 120 Axinoides kola Unnithan, 1957 121 Axinoides strongylurae n. sp. ALLOPSEUDAXININAE Yamaguti, 1963 122 Allopseudaxine katsuwonis (Ishii, 1936) 123 Allopseudaxine yaito n. sp. 124 Allopseudaxinoides euthynni Yamaguti, 1966 125 Allopseudaxinoides vagans (Ishii, 1936) n. comb. M O N A X I N I N A E Unnithan, 1957 126 Allomonaxine carangoides Yamaguti, 1965 H E T E R A X I N I N A E Unnithan, 1957 127 Heteraxinoides caprodontis n. sp. SIBITREMATINAE Yamaguti, 1966 128 Sibitrema poonui Yamaguti, 1966 CYPSELUROBRANCHITREMATINAE Yamaguti, 1966 129 Cypselurobranchitrema spilonotopteri Yamaguti, 1966 CEMOCOTYLIDAE Yamaguti, 1963 130 Cemocotylella carangis n. sp. GASTROCOTYLIDAE Price, 1943 GASTROCOTYLINAE Sproston, 1946 131 Gastrocotyle trachuri van Beneden et Hesse, 1863 132 Pseudaxine decapteri n. sp. 133 Pseudochauhanea sphyraenae Yamaguti, 1965 134 Neothoracocotyle acanthocybii (Meserve, 1938)

17

i8

Subfamily Family Subfamily

Subfamily Subfamily

Family Superfamily Family Subfamily

Yamaguti, 1965 135 Areotestis sibi Yamaguti, 1965 MICROCOTYLIDAE Taschenberg, 1879 MICROCOTYLINAE Monticelli, 1892 136 Microcotyle bothi n. sp. 137 Microcotyle emmelichthyops n. sp. 138 Microcotyle polymixiae n. sp. 139 Aspinatrium kahala n. sp. 140 Bivagina kyphosi n. sp. M E T A M I C R O C O T Y L I N A E Yamaguti, 1963 141 Metamicrocotyla mugilis n. sp. PROSTATOMICROCOTYLINAE n. subfam. 142 Prostatomicrocotyla kuhliae n. g., n. sp. 143 Prostatomicrocotyla maomao n. sp. ALLOMICROCOTYLIDAE Yamaguti, 1965 144 Allomicrocotyla onaga Yamaguti, 1965 POLYSTOMATOIDEA Price, 1936 HAXABOTHRIIDAE Price, 1942 HEXABOTHRIINAE Price, 1942 145 Hexabothrium dasyatis n. sp. 146 Erpocotyle sphyrnae (MacCallum, 1931) AREOTESTINAE

APPENDIX Order Family Subfamily

ASPIDOCOTYLEA Monticelli, 1892 ASPIDOGASTERIDAE Poche, 1907 ASPIDOGASTERINAE Chauhan, 1954 147 Lobatostoma albulae n. sp.

3| Description and discussion of species

Subclass Order Superfamily Family Subfamily

1 HABITAT HOLOTYPE DESCRIPTION

M O N O G E N E A

van Beneden, 1858

MONOPISTHOCOTYLEA

Odhner, 1912

CAPSALOIDEA Price, 1936 CAPSALIDAE Baird, 1853 BENEDENIINAE

Johnston, 1931

Benedenia bodiani n. sp.

FIGURE 1

Gill of Bodianus bilunulatus (local name "a'awa"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 87. (Based on 17 whole mounts.) Body flattened elliptical, 1.5-2.6 mm long, 0.5-1.35 mm wide at about middle of body proper. Prohaptor sucker-like, with thin flared border, 0.14-0.25 X 0.2-0.31 mm. Opisthohaptor circular, aseptate, well constricted off from body proper, 0.35-0.62 mm in transverse diameter, with three pairs of anchors and a number of marginal hooklets, fringed with thin membrane which is up to 38 ¡¡. wide and notched at marginal hooklets at irregular intervals. Anterior anchor 77105 n long, with ala on each side of anterior portion, terminating in two blunt processes; middle anchor falcate, 77-100 long; posterior anchor flattened from side to side, 62-95 ^ long from base to height of curve of claw-like point. Two pairs of eyespots anterodorsal to pharynx. Pharynx spherical, nearly smooth, 0.1-0.23 X 0.14-0.35 mm. Ceca dendritic, not united posteriorly. Testes oval, 0.11-0.36 X 0.16-0.4 mm, juxtaposed in midregion of body proper, with two Goto's organs behind. Vas deferens swollen between ovary and left testis, passing dorsal to left end and anterosinistral margin of vitelline reservoir, and after forming convolutions in front of vitelline reservoir it enters the cirrus pouch at its base, where it forms conspicuous tortions and then leads into narrow ejaculatory duct. Prostatic reservoir large, rounded, 0.1-0.3 X 0.04-0.2 mm, provided outside with a layer of circular muscle fibers which is continuous with the more strongly developed circular muscle layer of the cirrus pouch, containing dark oval mass of secretion, surrounded by numerous prostatic cells which are delimited from the surrounding tissue by a thin membranous capsule. The prostatic duct enclosed in the cirrus pouch is provided with thick wall of circular muscle fibers throughout its length and, finally uniting with the ejaculatory duct, passes through the cirrus. Cirrus pouch subcylindrical,

20

mm, provided throughout with circular muscle fibers; it extends obliquely mesad to a little beyond the median line behind the pharynx. The genital atrium enclosing the cirrus and cirrus pouch extends to the base of the cirrus pouch. Genital pore just posterior to left end of left anterior haptoral sucker. Ovary ovoid, 0 . 1 - 0 . 2 1 X 0 . 0 9 - 0 . 2 5 mm, situated between right testis and vitelline reservoir, with some vitelline follicles between itself and right testis. Uterine egg observed in a specimen 1.6 mm long, pentagonal, 116 long by 107 ¡i wide, with terminally enlarged filament at posterior end. Vagina opening dorsally near left margin of body a little posterior to genital pore. Vaginal duct narrow; seminal receptacle 5 0 - 6 0 ¡x wide. Vitellaria co-extensive with intestinal branches; vitelline reservoir 0 . 0 4 - 0 . 1 6 X 0 . 1 1 - 0 . 3 4 mm, anterosinistral to ovary. This species resembles Benedenia lolo n. sp. very closely, only differing in the anterior and middle haptoral anchors being definitely smaller. In B. lolo they are 1 5 0 - 1 7 0 ¡x and 1 8 0 - 2 0 0 ¡x respectively, whereas in the present species they are 7 7 - 1 0 5 ¡x and 7 7 - 1 0 0 ¡x long respectively. Nevertheless the posterior anchor of both species are nearly equal in length. 0.15-0.4 X 0.03-0.06

DISCUSSION

2 HABITAT

HOLOTYPE DESCRIPTION

Benedenia hawaiiensis n. sp.

FIGURE 2

Gill and body surface of Priacanthus cruentatus (type host), Mulloidichthys samoensis, Parupeneus multifasciatus, P. bifasciatus, P. chryserydris, P.pleurostigma, P.porphyreus, Dascyllus albisella, Amanses carolae, A. pardalis, A. sandwichiensis, Acanthurus nigrofuscus, A. dussumieri, Synodus dermatogenys, Abudefduf abdominalis, Chromis oralis, Chaetodon miliaris, Alutera scripta, Pervagor spilosoma, Naso hexacanthus, Holocentrus scythrops, H. spinifer, Scarus sordidus, and Xanthichthys ringens. U.S. Nat. Mus. Helm. Coll., S.Y. No. 88. (Based on 5 2 whole mounts, of which 1 3 are from the type host.) Body elliptical, 0 . 8 7 - 3 . 0 mm long, with maximum width of 0 . 4 - 1 . 4 mm at level of middle. Opisthohaptor usually a little longer than wide, 0 . 1 8 - 0 . 6 5 mm in length, provided with marginal membrane up to 30 p wide and notched opposite marginal hooklets; 12 marginal hooklets were counted, two of them between posterior anchors. At the ventral center of the opisthohaptor is a circular pit corresponding to the location where the haptor is attached to the body proper by a short stalk. Anterior anchor 5 0 - 1 8 0 ¡I long, with acute point anteriorly and alate subapically, bifurcate and blunt-pointed posteriorly; middle anchor 4 9 - 2 0 0 ¡x long, with ventrally curved claw; posterior anchor also with claw-like point, 3 8 - 1 2 0 ¡x long. Prohaptor saucer-shaped, 0 . 0 7 - 0 . 3 2 mm long, with glandular tissue along anterolateral margin. Two pairs of eyespots anterodorsal to pharynx. Pharynx 0 . 0 7 - 0 . 2 X 0 . 0 9 - 0 . 2 5 mm, with a slight notch on each lateral margin. Ceca profusely branched, but not united posteriorly. Testes oval,

0.12-0.42 X 0.07-0.35

mm, situated side by side at equa-

Capsalidae

DISCUSSION

3 HABITAT HOLOTYPE DESCRIPTION

21

torial level, with two Goto's organs immediately behind. Vas deferens winding as usual in front of vitelline reservoir, crossing uterus dorsally, then slightly inflated, entering cirrus pouch at its base; ejaculatory duct running straight alongside prostatic duct, with which it joins at the base of the cirrus. Cirrus pouch 0 . 1 2 - 0 . 5 mm long, up to 2 5 - 6 0 ¡x wide, with well developed circular muscle fibers, extending obliquely from behind pharynx toward anterior lateral margin; cirrus subcylindrical, 15-70 ¡x long. Prostatic reservoir oval to elliptical, 0 . 0 5 - 0 . 2 4 X 0 . 0 2 - 0 . 1 6 mm, situated obliquely dextroposterior to cirrus pouch, with its muscular efferent duct leading into prostatic duct at base of cirrus pouch; latter duct with stronger circular muscles throughout its length and uniting with ejaculatory duct at base of cirrus. Genital atrium extending to near base of cirrus pouch, opening beneath posterior end of left prohaptor. Ovary subglobular, 5 8 - 2 0 0 X 5 0 - 3 5 0 p, situated immediately in front of testes, from which it may be separated by a strand of vitelline follicles. Uterus opening into genital atrium near its base; eggs 1 1 0 - 1 2 5 X 9 0 - 1 2 0 P in life; filament up to 75 /x or longer. Vitellaria co-extensive with intestinal branches; vitelline reservoir anterosinistral to ovary, 3 0 - 1 0 0 X 5 0 - 2 0 0 ¡x. Vagina opening dorsally a little behind genital pore. Receptaculum seminis vaginae retort-shaped, 6 0 - 1 8 0 X 3 0 - 1 0 0 ¡x, in front of vitelline reservoir. This species differs from the most closely related Benedenia epinepheli (Yamaguti, 1937) Meserve, 1938 in the cirrus pouch extending farther inwards than it does in B. epinepheli and in the largest anchor being alate subapically instead of apically.

Benedenia lolo n. sp.

FIGURE 3

Gills of Coris gaimardi (type host), C. flavovittatus, C. sp.; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 89. (Based on 4 0 whole mounts.) Body flattened elliptical, 1 . 4 - 3 . 0 mm long by 5 0 - 1 1 3 p, wide at about middle. Prohaptor disc-shaped, 0 . 1 1 - 0 . 2 5 X 0 . 0 9 - 0 . 3 mm, each with compact masses of dark-staining cells in its anterolateral portion. Opisthohaptor circular or nearly so, 0 . 3 7 - 0 . 8 X 0 . 3 2 - 0 . 8 mm, with three pairs of anchors and 14 marginal hooklets; fringed with a delicate membrane which is up to 35 ¡x wide anteriorly and more or less notched at each marginal hooklet at different intervals; hooklets of the anterior-most pair are 10 /A long and 265 ¡x apart one from the other, those Of the posterior-most pair a little shorter and 95 ¡x apart. Anterior anchor 9 0 - 2 4 0 fx long, with two blunt ends posteriorly; middle anchor 1 1 0 - 2 5 0 fi long from blunt anterior end to height of curve of blade, with a longitudinal ala along its concave side, and a sharp, strongly recurved claw; posterior anchor 7 0 - 1 2 5 ¡x long from its truncate base to height of curve of blade. Two pairs of eyespots immediately anterior to mouth aperture. Pharynx 0 . 1 - 0 . 2 4 X 0 . 1 - 0 . 2 3 mm, with a postequatorial notch on each side. Ceca not united posteriorly, with numerous ramified lateral branches

22

throughout their length and some small medial branches in posttesticular area. Testes ovoid, with uneven surface and perforating canals (five on the right and three on the left in the type), 0.12-0.3 x 0.08-0.23 mm, directly side by side, pre-equatorial; two small Goto's organs present close together immediately behind testes. Vas deferens, strongly convoluted just in front of vitelline reservoir, passing dorsal to uterus, and then curving to the right, enters the cirrus pouch at its proximal end, where it turns back on itself and continues as a straight duct alongside the prostatic duct with which it finally opens into the base of the cirrus. Cirrus pouch cylindrical, 130-360 X 30-60 ix, provided with strong circular muscle fibers, enclosing ejaculatory duct and muscular prostatic duct. Cirrus elongate, 25-100 ¡x long, smooth, provided with strong longitudinal muscles, may or may not project out of the genital atrium. Genital pore immediately behind left prohaptor; genital atrium enclosing nearly entire cirrus pouch and cirrus. Prostatic reservoir subcylindrical to oval, 70-300 X 40-140 ¡x, filled with prostatic secretion, and enclosed in a capsule of fine circular muscle fibers. This capsule appears to continue into the cirrus pouch, but differs from it in consisting of much finer muscle element. The narrow efferent duct from this reservoir soon enters the cirrus pouch at its base; prostatic duct provided with its own muscular walls. Ovary rounded, with smooth or uneven surface, 50-200 X 40-170 ¡x, situated at junction of anterior with middle third of body, separated from testes by vitelline follicles. Uterus passing obliquely forward between left vas deferens and right prostatic reservoir, forming ootype just before opening into genital atrium; collapsed eggs about 0.15 mm long, with winding filament at posterior pole. Vitelline follicles co-extensive with intestine and its branches, extending into space between prohaptors and pharynx to preocular area, confluent in posttesticular area; right collecting vitelline duct passing on the right side of pharynx, prostatic reservoir, ovary, and testes, with several simple or ramified outer branches; left duct passing on the left side of pharynx, vas deferens, and testes and dorsal to cirrus pouch, both ducts emptying from right or left side respectively into vitelline reservoir, which may be irregularly incised, 30-130 X 60-230 ¡x, and extends transversely across anterior or anterosinistral surface of ovary. Vagina opening dorsally near left margin of body at midlevel of pharynx; vaginal duct narrow, running obliquely inward and then longitudinally to open into vitelline reservoir. Receptaculum seminis vaginae indistinct. DISCUSSION

This species differs from the most closely related Benedettici epinepheli suc (Yamaguti, 1937) ^ m i n o r details as that the pharynx is constricted on each lateral margin posterior to the midlevel. In B. epinepheli, however, the testes are definitely large in relation to the ovary and are not separated from the ovary by vitelline follicles. The specific name is the local name for the host. The relatively large size of the opisthohaptor in B. lolo is one of the most outstanding features of the species.

Capsalidae

4 HABITAT HOLOTYPE DESCRIPTION

Benedenia scan n. sp.

33

FIGURE 4

Gills of Scarus sordidus (local name "uhu"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 90. (Based on five whole mounts.) Body approximately elliptical, 1 . 5 - 3 . 8 mm in length, with maximum width of 0 . 5 5 - 1 . 2 5 mm in midregion. Opisthohaptor 0.4-0.8 mm in diameter, with marginal membrane up to 0.08 mm wide, and a central pit where the haptor is attached to the body proper. Anterior anchor pointed anteriorly and bifid at posterior end, 8 0 - 1 2 5 Flong; middle anchor with stout root and apical claw, 9 3 - 1 3 0 p long; posterior anchor laminate, 9 0 - 1 5 0 p. long. Marginal membrane notched opposite point of posterior anchor as well as opposite marginal hooklets; six pairs of marginal hooklets 10-12 n long, disposed at intervals increasing from behind forward. Prohaptor saucer-shaped, 0 . 1 - 0 . 1 8 X 0 . 1 8 0.3 mm. Two pairs of eyespots anterodorsal to pharynx. Pharynx globular, without constrictions, 7 0 - 1 7 0 X 1 0 0 - 1 7 0 n; esophagus very short; intestinal limbs ramified, but apparently not confluent posteriorly, posterior-most branch reaching almost posterior end of body proper. Testes oval, juxtaposed, 0 . 1 8 - 0 . 3 7 X 0 . 1 3 - 0 . 3 3 mm, just pre-equatorial; Goto's organ irregular in outline, filled with finely granular cells, each containing a rounded nucleus 10-12 p in diameter and provided with a distinct nucleolus; in one specimen this Goto's body is uniformly granular, with scattered nuclei, and the duct arising from the anterior end of this organ unites with its fellow of the other side and runs forward as a median duct passing between the two testes and finally empties into the swollen vas deferens lying immediately behind the ovary; just distal to this point the vas deferens opens into the swollen portion. It is worthy of note that the vas deferens which usually contains sperm alone is filled with sperm and somewhat colored granules coming from the Goto's organ. The latter granules are not discernible in the distal portion of the vas deferens, probably owing to their liquefaction. From this observation it seems certain that the Goto's organ is an accessory male gland sui generis. Vas deferens containing sperm and granules from the Goto's gland runs along the left margin of the ovary and winds its way forward along the vaginal duct, then turning to the right, crosses the uterus dorsally and finally penetrates the cirrus pouch at its base. Cirrus pouch claviform, 0 . 2 - 0 . 3 mm long by 3 0 - 7 0 p wide, well provided with inner circular muscle fibers proximally, but with longitudinal muscle fibers distally, containing tubular ejaculatory duct running alongside prostatic duct, the proximal portion of which is swollen and surrounded by strong circular muscle fibers. Cirrus proper reduced to a minute slender process perforated by a common ejaculatory duct resulting from union of ejaculatory duct and prostatic duct. Genital atrium extending deeply to near base of cirrus pouch. Prostatic reservoir oval, 0 . 1 1 - 0 . 3 2 X 0 . 0 8 - 0 . 1 3 mm, situated outside cirrus pouch medial to right intestinal limb in front of ovary. Genital pore beneath left prohaptor.

24

DISCUSSION

KEY TO SPECIES OF

Benedenia FROM HAWAIIAN FISHES

5 HABITAT

HOLOTYPE DESCRIPTION

Ovary oval to pyriform, longer than wide, 0.1-0.22 X 0.09-0.15 mm, separated from testes by vitelline follicles; germiduct arising from anterior end of ovary soon unites with the vitelline duct; ootype oblique, between prostatic reservoir and ascending vas deferens; no eggs observed. Vitellaria co-extensive with intestinal branches; vitelline reservoir oval, very small, 25-40 X 50-75 ¡x, situated anterosinistral to ovary. Vagina opening dorsally just posterior to cirrus pouch near its distal end; vaginal duct running parallel to cirrus pouch for a short distance, then parallel to ascending vas deferens, and provided with a thick cellular coat before opening into vitelline reservoir. This species is characterized by the fact that the anterior haptoral anchor is small as compared with the middle and posterior ones.

1

Opisthohaptor and anchors comparatively large: 2 Opisthohaptor and anchors small: 3 2 Anterior haptoral anchor 50-180 /» long; seminal receptacle well developed: B. hawaiiensis Anterior haptoral anchor 90—240 n long; seminal receptacle indistinct: B. lolo 3 Seminal receptacle, vitelline reservoir, and cirrus well developed: B. bodiani Seminal receptacle, vitelline reservoir, and cirrus poorly developed: B. scari Pseudobenedenia

elongata n. sp.

FIGURE 5

Gills of Priacanthus boops (type host), Pristipomoides sieboldii and Arnillo auricilla; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 91. (Based on four specimens from type host, five from second host and 10 from third host.) Body elongate, flattened subcylindrical, 1.3-3.4 m m ™ length, with maximum width of 0.39-0.95 mm in middle third. Two pairs of eyespots distinct. Opisthohaptor circular, 0.26-0.73 mm long, with scalloped marginal membrane 20-40 ¡x wide; anterior anchor about 70-160 p. long, with sharp point, subapically alate, bifid at root; middle and posterior anchors flattened laterally, claw-like apically, 70-120 ¡t, and 50-100 ¡x in length respectively. Prohaptor saucer-shaped, 90-190 X 150-300 y.. Mouth opening ventrally between two posterior eyespots. Pharynx musculo-glandular, 80-220 X 110-330 ¡j.; esophagus practically absent. Intestinal limbs branched, not confluent posteriorly. Testes elliptical, 0.16-0.4 x 0.1-0.26 mm, juxtaposed in anterior half of middle third of body or nearly equatorial. Vas deferens distended with sperm, convoluted in front of vitelline reservoir, crossing uterus dorsally, penetrating cirrus pouch near its base, and running forward close parallel to prostatic duct. Cirrus pouch claviform, curved, extending from behind posterosinistral corner of pharynx to right side of ootype, 0.2-0.3 mm long

Capsalidae

DISCUSSION

6 HABITAT HOLOTYPE DESCRIPTION

25

by 30-70 /i wide in region of strongly muscular prostatic duct, enclosing very small prostatic reservoir at its base. Prostatic duct provided proximally with strong circular muscles, but devoid of them distally as in other members of the genus, may be convoluted in the swollen portion of the cirrus pouch. Cirrus very slender, smooth. Genital pore opening on left body margin beneath left prohaptor. Ovary subglobular, 0.08-0.18 X 0.07-0.23 mm, in posterior part of anterior third or at junction of anterior with middle third of body, well separated from testes by vitelline follicles. Eggs rounded, 0.13-0.165 X 0.1-0.13 mm, with a very fine, long, convoluted filament. Uterus opening into genital atrium at its base near posterosinistral corner of pharynx. Vitellaria co-extensive with intestine and its branches, with very conspicuous main trunk along intestinal limbs; vitelline reservoir 50-130 X 70-190 ¡x, immediately anterosinistral to ovary. Vagina opening very close to genital pore; vaginal duct narrow throughout; receptaculum seminis vaginae oval, 50-110 X 30-100 ¡x, immediately anterosinistral to vitelline reservoir, into which it empties by a short narrow seminal duct. This species bears a certain resemblance to Pseudobenedenia merinthe n. sp. in body shape, but differs from it in the following points: the cirrus pouch is smaller, the prostatic reservoir is rudimentary or nearly absent, and the seminal receptacle is oval instead of fusiform.

Pseudobenedenia merinthe n. sp.

FIGURE 6

Gills of Merinthe macrocephala (local name "o'opu kai nohu"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 92. (Based on 30 whole mounts.) Body elongate, flattened elliptical, 0.4-3.5 mm in length, with maximum width of 0.18-1.4 mm in middle third. Opisthohaptor with scalloped marginal membrane, 0.18-0.55 mm in diameter; anterior hook with curved, blunt point, 70-120 ¡x long; middle and posterior hooks alate, with claw-like point, 50-90 ¡x and 70-100 ¡x long respectively. Prohaptor saucer-shaped, 50-120 X 88-200 ¡x, with slightly notched frontal plate between. Pharynx wider than long, 60-200 X 100300 /x. Intestinal limbs branched, not confluent posteriorly. Testes elliptical, 0.17-0.5 X 0.1-0.4 m m ' directly juxtaposed in middle third of body. Vas deferens winding forward, crossing ootype or uterus dorsally, then running backward along cirrus pouch, at the base of which it penetrates the pouch, to be continued into ejaculatory duct. Cirrus pouch long, claviform, 0.3-1.0 X 0.042-0.15 mm, containing oval prostatic vesicle 20-130 fx wide at base, reaching to anterodextral side of ovary; prostatic duct with a very thick wall of circular muscle fibers for its proximal portion, but less muscular distally as it runs alongside ejaculatory duct, which is also somewhat muscular proximally but less muscular distally; the two ducts run alongside each other for almost entire length of the cirrus pouch and join together at the base of the cirrus at the level of

3.6

DISCUSSION

7 HABITAT

HOLOTYPE DESCRIPTION

the pharynx. Cirrus rather slender, about 80 X 14 p in the type, lying in genital atrium or projecting out of it. Common genital pore on left margin of body close to outer end of left prohaptor. Ovary ovoid, 0.06-0.25 X 0.08-0.28 mm, pretesticular, median; shell gland complex well developed; uterus opening into genital atrium behind posterosinistral corner of pharynx. Eggs fusiform, approximately 120 p long by 9 0 - 9 5 ju, wide, with short anterior and much longer, convoluted, fine, posterior filament. Vitellaria co-extensive with intestinal limbs and their branches, not extending into prepharyngeal frontal area; vitelline reservoir ovoid, preovarian; there may be two reservoirs in front of the ovary, the right one being a little larger than the left, the latter is, however, the true vitelline reservoir, because it unites on one side with receptaculum seminis vaginae by a narrow seminal duct and on the other side with the ootype by vitelline duct. Although the right reservoir may occasionally not be conspicuous as in the type, it constitutes one of the distinctive characters of the present species. Vagina opening on left body margin immediately posterior to genital pore; receptaculum seminis vaginae elongate, thickwalled, 0.15 mm long in the type. This species differs from Pseudobenedenia noblei (Menzies, 1 9 4 6 ) in the body being more elongate and in the testes being equatorial instead of postequatorial. In the body shape it rather resembles P. elongata n. sp., but differs from the latter in that the ovary is not so wide apart from the testes and the cirrus pouch extends farther backward. In contrast with P. noblei and P. elongata, two pairs of eyespots could not be detected in any of the specimens I examined.

Pseudobenedenia oralis n. sp.

FIGURE 7

Body surface of Etelis marshi (local name "ula-ula," type host), E. carbunculus, Priacanthus boops; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 93. (Based on four whole mounts.) Body proper oval, with oval opisthohaptor attached ventroterminally, 1 . 8 7 - 2 . 3 mm in total length, 0 . 9 - 1 . 3 mm wide in midregion. Two pairs of eyespots anterodorsal to pharynx. Opisthohaptor 0.46-0.5 X 0 . 4 5 - 0 . 5 2 mm, with posterior end somewhat produced backward, provided with scalloped marginal membrane 20 ¡x wide; anterior anchor 0 . 1 4 - 0 . 1 7 mm long by 30 ¡x. wide, with arrowhead-like wing at its pointed anterior end, and subterminal protuberance greatly reduced; middle and posterior anchors 0 . 1 5 - 0 . 2 mm and 0 . 1 1 - 0 . 1 8 mm long respectively, flattened laterally, attenuated anteriorly, each terminating in a sharp claw-like point. Prohaptor saucer-shaped, 0 . 1 1 - 0 . 1 4 X 0 . 1 7 - 0 . 2 mm. Pharynx cellular, with marginal incisions, 0 . 1 3 - 0 . 1 9 X 0 . 1 7 - 0 . 2 7 mm, produced forward to mouth aperture which opens as a longitudinal slit. Intestinal limbs branched, not confluent posteriorly. Testes round, 0 . 1 9 - 0 . 3 6 X 0 . 1 8 - 0 . 2 6 mm, juxtaposed in anterior part of middle third of entire body, with few vitelline follicles between them and

Capsalidae

DISCUSSION

KEY TO SPECIES OF

Pseudobetiedenia

FROM HAWAIIAN FISHES

vj

ovary. Goto's gland present. Vas deferens forming a transverse loop immediately in front of vitelline reservoir, crossing uterus dorsally, coming to lie dorsal to cirrus pouch, which it penetrates and leads into the ejaculatory duct. This duct first describes a small loop on the ventral surface of the prostatic vesicle and then runs forward along dorsal side of the prostatic duct, with which it finally unites at the base of the cirrus. Prostatic duct is provided proximally with a thick muscular coat, which is, however, reduced distally in the attenuated portion of the cirrus pouch. Prostatic reservoir oval, 0 . 0 7 - 0 . 1 3 X 0 . 0 5 - 0 . 0 9 mm, entirely enclosed in cirrus pouch at its swollen base. Cirrus pouch claviform, curved, 0 . 3 - 0 . 3 3 X 0 . 0 8 - 0 . 1 mm, provided with fine circular and longitudinal muscle fibers, extending from left side of pharynx to right side of shell gland complex. Cirrus filiform, long, smooth, projecting out of genital pore for a considerable length ( 0 . 1 7 - 0 . 3 6 mm). Genital atrium narrow, receiving uterus to left of pharynx, opening beneath left prohaptor. Ovary subglobular, 0.1-0.17X0.11-0.2 mm, pre-equatorial, median, separated from testes by narrow strand of vitellaria; shell gland occupying space bordered by cirrus pouch, vitelline reservoir, and vas deferens; no uterine eggs; uterus opening into genital atrium to left of pharynx. Vitellaria co-extensive with intestine and its branches; vitelline reservoir rounded quadrangular, or bean-shaped, 0 . 0 8 - 0 . 1 7 X 0 . 1 5 - 0 . 2 1 mm, immediately anterosinistral to ovary. Vagina opening very close to genital pore; vaginal duct very narrow distally, but medial to left intestinal limb it forms a fusiform thick-walled dilatation (100 ¡x by 30 ¡x in the type) which in turn unites with the vitelline reservoir by a narrow seminal duct. This species resembles Pseudobetiedenia nototheniae Johnston, 1 9 3 1 in body shape, but differs from it in the longer cirrus pouch and in the position of the genital pore. A detailed comparison is not possible because of the lack of necessary information concerning Johnston's species. The specific name refers to the shape of the body proper. The arrowhead-like structure of the anterior haptoral anchor and the long filiform cirrus are the most distinctive characters.

1 Body oval; vagina fusiform, with thick-walled seminal receptacle: P. oralis BOD Y elongate; vagina with or without thick-walled seminal receptacle:

Z

2 Cirrus pouch reaching to near ovary; receptaculum seminis vaginae thick-walled: P. meritithe Cirrus pouch far apart from ovary; receptaculum seminis vaginae not thick-walled: P. elongata 8 HABITAT HOLOTYPE DESCRIPTION

Allobenedenia

epinepheli n. sp.

Gills of Epinephelns quernus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 94. (Based on two whole mounts.) Body elongate,

FIGURE 8

3.33-3.37

mm in total

28

length including opisthohaptor, up to 1.1 mm wide in midregion. Opisthohaptor 0.4-0.56 X 0.53-0.7 mm; marginal membrane up to 50 wide, regularly incised at short intervals; anterior anchor 0.11-0.15 mm long, pointed anteriorly, alate subapically, bifurcating posteriorly into two conical projections of nearly equal length; middle and posterior anchors undulating, flanged, 54-60 ¡A. and 50-60 ¿1 long respectively. Prohaptor hood-like, 0.45-0.53 mm in transverse diameter, with distinct midventral notch, on each side of which is a sucker-like structure. Two pairs of distinctly lensed eyespots dorsal to mouth aperture. Pharynx 0.14-0.19 X 0.18-0.2 mm; its wall with irregularly outlined cells containing cytoplasmic granules, showing no muscular element. Intestinal limb with a number of ramified outer branches throughout its length, and less numerous inner branches posterior to testes, not united posteriorly. Testes elliptical, 0.45-0.6 X 0.21-0.32 mm, directly juxtaposed, just preequatorial. No Goto's gland. Terminal genitalia just as in Allobenedenia convoluta (Yamaguti, 1937). Cirrus pouch tubular, convoluted to right of median line between prostatic reservoir and ovary. Prostatic reservoir 0.12-0.13 mm in diameter, medial to right intestinal limb, from which it is separated by the cirrus pouch. Genital pore immediately beneath posterosinistral border of prohaptoral hood. Ovary ovoid, 0.17-0.25 X 0.17-0.2 mm, separated from testes by a band of vitelline follicles, contiguous with vitelline reservoir. Uterus containing one mature egg in the type, opening into genital atrium near genital pore. Egg trihedral, with flat base, 110 ¡x long by 70 ¡J. wide, with a long winding filament arising from one basal angle. Vagina tubular, narrow, opening immediately behind genital pore on left margin of body, fusiform proximally and provided with transverse muscles. No distinct seminal receptacle differentiated. Vitellaria extending from behind prohaptoral hood to level of anterior end of opisthohaptor, confluent between ovary and testes as well as in posttesticular median field; vitelline reservoir ovoid, 0.15-0.21 X 0.11-0.16 mm, pressed against anterosinistral side of ovary.

TABLE

1

D I F F E R E N C E S I N M E A S U R E M E N T S ( I N M M ) OF A .

convoluta

AND A .

epinepheli n. sp.

CHARACTER

A. convoluta

A. epinepheli

Prohaptoral hood (transverse diameter)

0.88

0.45-0.53

Opisthohaptor

1.0

Length of anterior haptoral anchor

0.25-0.26

0.11-0.15

Pharynx

0.28

0.37

0.14-0.19 X 0.18-0.2

Testes

0.65-0.66 X 0.5-0.53

0.45-0.6 X 0.21-0.32

Ovary

0.275 X 0.31

0.17-0.25 X 0.17-0.2

Length of vitelline reservoir

0.26

0.15-0.21

1.2

X

X

0.4-0.56 X 0.53-0.7

Capsalidae

DISCUSSION

9 HABITAT HOLOTYPE DESCRIPTION

39

This species differs from the most closely related Allobenedenia convoluta (Yamaguti, 1937) from a Japanese fish of the same genus. In addition to possessing different characters of the anterior anchor, it differs markedly in the measurements of every organ, as shown in the table on page 28, although there is almost no difference in body size.

Pseudallobenedenia

apharei Yamaguti, 1966

FIGURE

9

Gill of Aphareus rutilans; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 45. (Based on 21 whole mounts.) Body approximately fusiform, 2.6-5.3 m m long, up to 0.7-1.9 mm wide at about testicular level. Posterior extremity of body proper attenuated to a flap covering opisthohaptor dorsally. Opisthohaptor discoid, usually projecting a little beyond posterior end of body proper, 0.43-0.8 mm longitudinally except for scalloped marginal membrane 20-80 ¡x wide, with a central pit 0.1-0.15 mm in diameter; on the concave ventral surface there are three pairs of anchors but no definite septa or ridges, although several symmetrical radiating excretory vessels are seen bifurcating or not at their submarginal ends; anterior anchor 28-37 ¡i long from tip to posterior end, situated posterolateral to central pit; two posterior anchors close together, near posterolateral edge of opisthohaptor, longer J-shaped medial one slender, 18-33 P l°ng> shorter lateral one hook-shaped, with bifid root, 1 4 - 2 1 long. Prohaptors elliptical, saucer-shaped, 0.54-1.0 X 0.24-0.48 mm, connected dorsally by medianly incised frontal plate which never projects forward beyond the prohaptors. Mouth opening ventrally at level of posterior end of prohaptors, with one or two pairs of eyespots dorsally. Pharynx muscular, incised anteriorly into five lobes, more or less constricted laterally near broadly rounded posterior end, 0.22-0.52 X 0.24-0.65 mm. Esophagus short. Each intestinal limb giving off more or less dendritic outer branches, of which the anterior pair extends into the frontal plate, almost meeting in the median line; posterior-most pair sends out several outer branches reaching lateral edges of body and a few shorter inner branches probably anastomosing each other; no anastomosis between two main intestinal limbs posteriorly. Testes oval to elliptical, 0.28-0.8 X 0.18-0.5 mm, directly juxtaposed, largely in posterior part of middle third of body, with paired multinucleate Goto's glands immediately behind. Vas deferens running forward along left margin of ovary, convoluted just medial to left intestinal limb, then crossing uterus dorsally and coming to right side of median line, where it enters the cirrus pouch along with the prostatic reservoir and finally unites with the prostatic duct to lead into extremely long (2.0-3.0 mm or more) spicular cirrus. Prostatic cells massed around distal portion of vas deferens and prostatic reservoir which is elliptical, 0.1 X 0.05 mm in the type and lies longitudinally alongside the vas deferens. Cirrus pouch

3

O

somewhat muscular, small, containing winding vas deferens and more or less convoluted prostatic duct; both ducts joining together at distal end of cirrus pouch to form cirrus, which is enclosed throughout its length in the thin-walled, tubular, genital atrium, and may or may not project out of the genital pore. The genital atrium is continued from the wall of the cirrus pouch with the same diameter as the latter, but tapers into a long, narrow tubule running backward and then curving toward the left in front of the transverse vitelline duct; it turns back on itself to follow the same course as its proximal portion, and after passing beside the cirrus pouch, proceeds straight obliquely forward to open ventrosublaterally at the level of the posterior end of the pharynx on the left side. Ovary subglobular, 0.08-0.28 X 0.1-0.25 mm, situated medianly between anterior ends of testes; the winding germiduct arising from the anterior end of the ovary joins the duct from the vitelline reservoir and leads into the ootype, which passes into a long, wider, winding uterus often distended with eggs; distal portion of uterus running obliquely forward along with genital atrium, opening together with the latter by a common pore. Eggs rounded triangular in flattened condition, with extremely long, very fine antipolar filament at base, 0.1-0.12 X 0.1-0.11 mm as measured in life and in lactophenolglycerin-jelly. Vitelline follicles extending in lateral fields from level of posterior part or end of pharynx to base of posterior flap covering opisthohaptor, confluent in median line between testes and opisthohaptor, intruding into small area between transverse vitelline ducts and testes; transverse vitelline ducts united medianly, forming inconspicuous vitelline reservoir only 20-110 ¡x anteroposteriorly. Vagina opening ventral to uterus by a very small pore a little behind intestinal bifurcation; vaginal duct winding along with vas deferens medial to left intestinal limb; receptaculum seminis vaginae oval, 50-150 X 30-110 ¡x, lying between left transverse vitelline duct and ootype; seminal duct very short. Excretory vesicle funnel-shaped, symmetrical, opening dorsally at level of intestinal bifurcation. DISCUSSION

TABLE

2

This genus very closely resembles Allobenedenia Yamaguti, 1963 in gross anatomy, but differs in minor details as shown in the following table. D I F F E R E N C E S B E T W E E N Pseudallobenedenia

AND

Allobenedenia

Allobenedenia

Pseudallobenedenia

Frontal hood

present

absent

Cirrus

long

extremely long

Cirrus pouch

slender, convoluted

short or long, not convoluted

Genital atrium

not extremely long

extremely long, convoluted or straight

Vaginal pore

marginal or submarginal

submedian, postbifurcal

Seminal receptacle

absent

well-developed

Vitelline reservoir

saccular, very distinct

no definite reservoir

CHARACTER

Capsalidae

31

The present species differs from Pseudallobenedenia opakapaka, to be described below, in that the former's cirrus pouch is reduced to a hemispherical structure, because the vas deferens and prostatic duct join together much sooner than they do in P. opakapaka, and that the genital atrium is much longer, is often convoluted, and contains an extremely long cirrus. The unusually long and wide uterus in P. apharei is worth noting.

10 HABITAT

HOLOTYPE DESCRIPTION

Pseudallobenedenia opakapaka Yamaguti, 1966

FIGURE 1 0

Gill of Pristipomoides microlepis (local name "opakapaka"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 46. (Based on three whole mounts.) Body elongate, distinctly constricted immediately behind prohaptor, 3.0-5.5 mm in total length including opisthohaptor, up to 0.1-0.15 m m a t l e v e l °f testes. Opisthohaptor bellshaped, 0.6-0.8 mm in transverse diameter, provided with a scalloped marginal membrane. There are three submedian pairs of weakly developed anchors on the inner surface of the posterior half of the opisthohaptor; anterior anchor rod-shaped, 40-50 /i long, middle and posterior anchors a little apart from the anterior, close together near haptoral margin; middle one somewhat undulating, barbed distally, 40-43 jj, long, posterior one hook-shaped, 18-25 ¡x long. Prohaptor oval, saucer-shaped, glandular, 0.210.28 mm long; between the two haptors is seen the truncate head end level with the anterior end of the haptor. Two pairs of eyespots anterodorsal to pharynx. Pharynx subglobular, without constriction, 42-58 X 52-62 fi. Esophagus very short, surrounded on each side by postpharyngeal cells, whose ducts appear to open into the pharyngeal lumen close to its posterior end. Intestinal limbs with comparatively long, subdivided outer branches, terminating separately a short distance away from posterior end of body. Testes elliptical, juxtaposed at anterior part of middle third of body, 0.37-0.7 X 0.17-0.28 mm, with paired Goto's gland immediately behind. Multinucleate organs like Goto's were found immediately in front of the testes and beside ovary. Vas deferens convoluted between left intestinal limb and shell gland complex, then forming a very long horseshoe-shaped loop across uterus and cirrus pouch dorsally, penetrating cirrus pouch at its anterior base, finally joining prostatic duct at posterior end of cirrus pouch. Cirrus pouch cylindrical, 0.2-0.7 mm long, arcuate, strongly muscular, swollen at its forwardly directed base, situated longitudinally between right intestinal limb and uterus, containing prostatic duct and vas deferens, both of which are straight, narrow, and close together, though convoluted at the anterior base of the cirrus pouch. Cirrus spicular, long, enclosed in sheath-like genital atrium, which extends from the posterior distal end of the cirrus pouch to the genital pore along the dorsal side of the cirrus pouch. This overlapping portion is shown separately in the figure. Prostatic reservoir elongate, 80-90 X 100-130 /¿, situated immedi-

32

DISCUSSION

11 HABITAT HOLOTYPE DESCRIPTION

ately in front of base of cirrus pouch. Genital pore common, just posterosinistral to pharynx. Ovary subglobular, 0 . 1 7 - 0 . 2 7 X 0 . 1 7 - 0 . 2 2 mm, situated between two testes and vitelline reservoir. Shell gland strongly developed. Uterus distended with eggs. Eggs rounded pyramidal, with triangular base in balsam mounts, 0 . 1 2 - 0 . 1 4 X 0 . 1 2 - 0 . 1 5 mm in life, with very fine, long filament at one basal corner. Vagina opening ventrally in left submedian line a little posterior to intestinal bifurcation; vaginal duct thick-walled, running straight backward and opening into oval seminal receptacle which measures 100 /A by 80 ¡i in the type. Vitellaria co-extensive with intestine and its branches; vitelline reservoir transversely elongated, not forming a compact mass, 60-90 ¡x anteroposterior^. Paired excretory vesicles conspicuous at level of uterus. For the differences between this species and the type species, see the description of the latter.

Lagenivaginopseudobenedenia etelis Yamaguti, 1966

FIGUKE

11

Gill of Etelis carbunculus (local name "onaga"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 47. (Based on three whole mounts.) Body elliptical, flat, 2.9-4.3 m m ' n total length, 1.8-2.3 m m wide in midregion; head and neck region contracted and well separated from trunk. Opisthohaptor elliptical, 0.53-0.75 mm long, with finely scalloped marginal membrane 3 0 - 7 0 /x wide and three pairs of anchors; number of marginal hooklets not determined; anterior anchor 0.13-0.17 mm long, sharp-pointed anteriorly, nonalate, with two small blunt stumpy processes of unequal length at posterior end; middle and posterior anchors definitely smaller than anterior; middle one slender, 50-80 fi long, with undulating root and minute terminal claw; posterior one enlarged and flattened from side to side basally, 30-40 /x long, terminating in a minute claw. Prophaptors saucer-shaped, close together, 0.190.23 X 0.36-0.42 mm, containing glandular tissue which extends not only backward but also inward to be confluent in the median line posterior to somewhat incised frontal margin. Two pairs of eyespots present anterodorsal to pharynx. Pharynx spherical, 0.27-0.29 X 0 . 3 - 0 . 3 1 mm, glandular rather than muscular, papillate internally. Esophagus practically absent. Ceca with numerous dendritic outer branches, not confluent posteriorly. Testes elliptical, 0.31—0.5 X 0.2—0.34 mm, juxtaposed contiguously at anterior part of middle third of body. Rudimentary Goto's organ present. Vas deferens convoluted immediately anterosinistral to vitelline reservoir, then winding along posterior wall of cirrus pouch, which it penetrates from the dorsal side; after entering the cirrus pouch it pursues a short winding course, then a long straight course alongside the distal portion of the prostatic duct, with which it finally unites to be continued into the cirrus. Cirrus pouch subcylindrical, thin-walled, 0.25-0.4 X 0.08-0.1

Capsalidae

DISCUSSION

12 HABITAT HOLOTYPE DESCRIPTION

33

mm, curved transversely behind pharynx, containing at its base a small, tubular, prostatic reservoir and cylindrical pars muscularis of prostatic duct which is 0.1-0.13 mm long and provided with a thick coat ( 3 0 - 6 0 ¡J. wide) of fine circular muscle fibers. Prostatic cells distributed around base of cirrus pouch. Cirrus elongate conical, pointed, 0.42 X 0.06 mm in the type; it may or may not project out of genital pore. Common genital pore posterosinistral to pharynx a little away from nearly right angle formed by neck and trunk. Ovary subglobular to oval, 0 . 1 5 - 0 . 3 X 0 . 0 9 - 0 . 2 2 mm, situated medianly, with its posterior end intercalated between two testes. Ootype spherical, 0 . 1 5 - 0 . 2 mm in diameter, provided with epithelial lining; uterus proper well separated from ootype, 0.2 mm wide in the type, opening into common genital pore by a funnel-shaped passage. No eggs observed. Vitellaria consisting of small follicles, co-extensive with intestine, wide apart anteriorly, but confluent posteriorly; paired longitudinal collecting ducts distended with yolk cells; transverse duct may be narrower, up to 70 ¡1 wide in the larger paratype, not forming a definite reservoir. Vagina lageniform, 0.17 mm wide in the type, muscular at its narrow neck, situated between uterus and right intestinal limb, opening almost midventrally behind cirrus pouch. Seminal receptacle oval, 0.1 X 0 . 0 5 5 m m the type, between vagina and vitelline reservoir. Excretory system not made out. This genus, characterized by the head and neck being marked off from the trunk and by the peculiar structure and position of the vagina, bears a certain resemblance to Pseudobenedenia Johnston, 1931, especially in the prostatic vesicle being enclosed in the cirrus pouch, but it seems justified to separate the genus in question from Pseudobenedenia on the basis of the above mentioned features. The compound generic name refers to the lageniform vagina and to the close relationship to Pseudobenedenia. For further details see Pacific Science 2 0 ( 4 ) : 4 I 9 ~ 4 3 4 .

Dioncopseudobenedenia kala Yamaguti,

1965

FIGURE

12

Gill of Naso unicornis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1. (Based on 1 8 whole mounts.) Body flattened, oval or more elongate, 2 . 1 - 4 . 2 X 0 . 6 - 2 . 0 mm. Opisthohaptor circular, 0 . 5 - 1 . 0 mm in diameter, aseptate, fringed with scalloped membrane up to 25 /* wide, provided with only one pair of slender, rather acicular spines 5 0 - 7 5 /x long behind the center. Prohaptor sucker-like, partly with glandular tissue, 0 . 1 6 - 0 . 3 mm in longer diameter, connected by a flat apical border of body proper. Two pairs of compact eyespots anterodorsal to pharynx. Mouth followed by a distinct prepharynx which consists of circular muscle lamellae and provided inside with more or less prominent rounded papillae. Pharynx subglobular, 0 . 1 4 - 0 . 3 4 X 0 . 1 6 - 0 . 3 8 mm, consisting mainly of radial muscle fibers enclosed in smooth capsule of circular muscle fibers. Intestinal

34

limbs with numerous subdivided outer branches and fewer short inner branches, not confluent posteriorly; outer branches with longitudinal anastomosis parallel to principal limb. Testes oval, 0 . 2 - 0 . 5 x 0 . 1 5 - 0 . 3 8 mm, directly juxtaposed, just pre-equatorial. Paired Goto's gland irregular in shape and size, containing a variable number of rounded nuclei and fine granules. Vas deferens convoluted in front of vitelline reservoir, penetrating cirrus pouch near its posterior end; ejaculatory duct well provided with circular muscles, joining prostatic duct at base of cirrus. Cirrus pouch claviform, 0 . 3 6 - 0 . 9 5 X 0 . 0 8 - 0 . 2 2 mm, with thick wall of circular muscle fibers, containing prostatic reservoir 0 . 1 3 - 0 . 3 3 mm long by 0 . 0 5 - 0 . 2 8 mm wide at base, occupied for greater part by muscular ejaculatory duct and prostatic duct with thick wall of circular muscle fibers. Prostatic duct may or may not be provided proximally with a small sphincter-like bulb. Prostate cells extensively developed among vitelline follicles in vicinity. Cirrus conical, unarmed, muscular, 10-15 f- l° n g- Genital atrium thin-walled, apparently extending inwards down to the point where the uterus opens into it. Genital pore immediately posterolateral to left prohaptor. Ovary subglobular to oval, 0 . 0 7 - 0 . 2 3 X 0 . 0 9 - 0 . 3 2 mm. Uterus opening into genital atrium at a distance of about 0.3 mm from genital pore in the type. Eggs about 120 x 80 with long filament. Vagina opening dorsally posterolateral to genital pore; vaginal duct forming elongate seminal receptacle 50 p wide in the type. Vitellaria co-extensive with intestinal branches; vitelline reservoir anterosinistral to ovary, 0 . 0 4 - 0 . 1 7 X 0.05-0.3 m m . DISCUSSION

13 HABITAT HOLOTYPE DESCRIPTION

This genus resembles Pseudobenedenia Johnston, 1 9 3 1 in internal anatomy, especially in the prostatic reservoir being enclosed in the cirrus pouch, but differs from it in possessing only one pair of rudimentary anchors instead of three pairs and also in the extensive development of prostate cells among the vitelline follicles. For further details see Pacific Science i9(i):56-58.

Dioncopseudobenedenia macracantha n. sp.

FIGURE 1 3

Gills of Naso unicornis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 9 5 . (Based on nine whole mounts.) Body flattened elliptical, 1 . 8 - 3 . 0 mm in length, with maximum width of 0 . 7 5 - 1 . 5 6 mm at middle third. Cuticle smooth. Opisthohaptor disc-like, 0 . 4 - 0 . 8 mm in diameter, with scalloped marginal membrane and one pair of anchors which corresponds to the anterior pair of Benedenia, pointed anteriorly, bifid at posterior end, measuring 1 0 0 - 1 5 0 ¡J. long by 1 2 . 5 - 2 0 ¡x. wide. Prohaptor sucker-like, with glandular tissue in its anterolateral portion. Two pairs of compact eyespots present. Mouth opening ventrally at anterior end of pharynx. No muscular prepharynx as seen in Dioncopseudobenedenia kala Yamaguti,

Capsalidae

35

1965. Pharynx 0.13-0.26 X 0.18-0.36 mm, irregular in outline, with numerous nucleated muscle columns projecting into lumen. Ceca with subdivided, short, inner and longer outer branches, of which the posterior ones reach to the posterior end of the body without being united together. Testes elliptical, juxtaposed in midregion of body, 0.32-0.6 X 0.220.41 mm. A pair of Goto's glands present. Vas deferens forming a transverse loop in front of vitelline reservoir and ovary, entering cirrus pouch nears its base. Cirrus pouch claviform, slender, 0.48-0.54 X 0.07-0.14 mm, with thick wall of circular muscle fibers, containing prostatic reservoir 0.1-0.19 mm long by 0.06-0.12 mm wide at its base; prostatic duct comparatively narrow, though provided with well developed circular muscles proximally, running close parallel to ejaculatory duct; cirrus tubular, slender, unarmed, 7.5-17.5 ¡i wide. Genital pore beneath posterolateral end of left prohaptor.

DISCUSSION

14 HABITAT

HOLOTYPE DESCRIPTION

Ovary rounded, 0.1-0.2 X 0.13-0.24 mm, pre-equatorial. Ootype containing abortive egg in the type; one filamented egg 100 wide, apparently normal, was seen in one paratype. Vitellaria profusely developed, intruding into pre-ocular space between two prohaptors, accompanying anterior-most cecal branch; vitelline reservoir anterosinistral to ovary, 0.070.1 X 0.15-0.2 mm. Vagina opening dorsally a little behind genital pore; vaginal duct forming a small seminal receptacle 8-10 /x wide and containing sperm before emptying into vitelline reservoir. This species differs from the type species of the genus in: (1) possessing a much more slender cirrus pouch and a slender cirrus; (2) the absence of a muscular prepharynx; (3) the structure of the pharynx; and (4) the larger haptoral anchors. The specific name refers to this last mentioned characteristic.

Oligoncobenedenia nasonis Yamaguti,

1965

FIGURE 1 4

Gills of Naso hexacanthus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 2. (Based on eight whole mounts.) Body flattened, oval to elliptical, 1.62.2 X 0.7-1.0 mm. Opisthohaptor circular, 0.34-0.48 mm in diameter, with scalloped marginal membrane which is 25 /i wide in the type 2 mm long, with a number of marginal hooklets at somewhat irregular intervals. Immediately behind the central pit of the opisthohaptor there is a pair of large anchors typical of Benedenia, 5 0 - 9 0 long; middle pair occurring in Benedenid lacking entirely; posterior marginal anchor lacking in 2 out of 8 specimens; when present it is only 25-35 M- l° n §> v e r y narrow, undulating, almost filiform, terminating in a minute claw posteriorly. Prohaptor oval, saucer-shaped, 0.1-0.2 mm long, with glandular tissue along anterolateral margin; body fold between two prohaptors usually notched in median line. Two pairs of compact eyespots anterodorsal to pharynx. Pharynx glandular rather than muscular, 0.08-0.12 X 0.12-0.15 mm, without marginal incision. Intestinal limbs ramified, not united posteriorly.

36

Testes oval to elliptical, closely juxtaposed in midregion of body, 0.220.35 X 0.18-0.33 m m > two pairs of Goto's glands immediately behind in median field. Vas deferens entering cirrus pouch at its base. Prostatic reservoir oval to elliptical, 100-180 X 60-100 ¡1, situated longitudinally just medial to right intestinal limb; prostatic duct well provided with circular muscle fibers. Cirrus pouch weakly muscular, subcylindrical, 100-175 X 20-25 /*» containing a narrow ejaculatory duct and a narrow muscular prostatic duct. Cirrus rather short, narrow, unarmed. Genital atrium enclosing cirrus pouch, extending but a little beyond the point where the uterus opens into it. Genital pore on a prominent marginal papilla projecting immediately posterolateral to left prohaptor at level of eyespots. Ovary subglobular, pre-equatorial, median, 0.13-0.2X0.09-0.14 mm. Uterus opening into genital atrium close to its base. No eggs observed. Vagina opening at top of papilliform protuberance on left body margin immediately behind genital pore; vaginal duct running obliquely backward, distinctly muscular for a distance of 70-80 p before leading into retort-shaped receptaculum seminis vaginae, which is 80-100 X 25-60 ¡i and lies in front of the vitelline reservoir. Vitellaria co-extensive with intestinal branches; vitelline reservoir anterosinistral to ovary, 40-80 X 70130 DISCUSSION

The present genus is distinguished from Benedenia Diesing, 1858 by possessing two pairs, occasionally only one pair, of haptoral anchors and by the structure of the male terminalia. For further details see Pacific Science 19(1) 158-60.

Subfamily

CAPSALINAE

15 HABITAT

HOLOTYPE DESCRIPTION

Johnston, 1929

Capsala gotoi n. sp.

FIGURE

15

Gills of Parathunnus sibi (type host) and on carapace of a caligoid copepod parasitic in buccal cavity of Neothunnus macropterus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 96. (Based on two whole mounts.) Body oval to elliptical in outline, 7 11.5 mm long, with maximum width of 2.8-7.3 m m midregion, armed dorsally along greater part of lateral margin with a longitudinal row of spiniform teeth, most of which form transverse rows or groups of 2 to 7 or 8, diminishing in size and number posteriorly, leaving posterior body margin entirely free. Opisthohaptor 1.2-2.15 x I - 1 - 2 - 1 mm, with a scalloped marginal membrane, scattered with numerous cuticular bosses all over ventral surface, which is divided by seven radial septae into a central and seven marginal areolae; circular central areola surrounded by a circle of a dozen large bosses and produced backward into a quadrangular recess, the lateral strand of which is armed with an unusually large pointed

Capsalidae

37

anchor 0.32-0.35 mm long by 50-60 ft wide. Prohaptor oval, 0.6-1.3 x 0.05-1.5 mm; frontal lobe between two prohaptors prominent, 1.0-2.1 mm wide, containing abundant vitelline follicles. Two pairs of very small eyespots in region of cephalic ganglia. Mouth aperture posteroventral to eyespots. Pharynx 0.85-1.38 X 0.85-1.35 mm, strongly muscular, with conspicuous postequatorial constriction. Intestinal limbs with numerous outer branches, apparently united anterior to opisthohaptor.

DISCUSSION

16 HABITAT HOLOTYPE DESCRIPTION

Testes rounded, small, occupying whole interintestinal field at middle third of body, separated one from another by a comparatively wide space in which vitelline follicles are distributed. Vas deferens passing between seminal receptacle and vitelline reservoir, turning back on itself immediately in front of right transverse vitelline duct, then tightly winding as usual to left of ootype, finally entering cirrus pouch at its base. Cirrus pouch claviform, 0.28 X 0.18 mm in the type 7 mm long, with well developed longitudinal muscles, containing slightly sigmoid ejaculatory duct (50 ¡x wide in the type) and prostatic reservoir. The latter lies at the base of the pouch and is produced into the efferent duct joining the ejaculatory duct at the distal end of the cirrus pouch. Cirrus cylindrical, smooth. Genital atrium provided with longitudinal muscles, extending from genital pore to distal end of cirrus pouch where it receives the uterus. Genital pore a little behind left prohaptor at level of anterior" part of pharynx. Ovary subglobular, 0.46-0.55 X 0.38-0.67 mm, median, at junction of anterior with middle third of body. Ootype fusiform; no uterine eggs observed. Vagina opening ventrally posterior (0.3 mm in the type) to genital pore; seminal receptacle oval, 0.27-0.32 mm in diameter. Vitellaria dendritic, profusely developed along intestinal branches, intruding into intertesticular space; vitelline reservoir rounded, 0.14-0.28 X 0.2-0.32 mm, anterosinistral to ovary. This species very closely resembles Capsala nozawae (Goto, 1894) from the same habitat in general anatomy, only differing in the dorsolateral margin of the body being armed with a longitudinal row or groups of teeth and in the haptoral anchors being much larger. In C. nozawae the longitudinal marginal row of teeth is absent, and the anchors are only 0.1-0.16 mm long.

Capsala neothunni n. sp.

FIGURE

16

Gills of Neothunnus macropterus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 97. (Based on four whole mounts.) Body elongate, 4.7-6.9 mm in total length, 1.9-3.0 mm wide at postequatorial level, with two pairs of eyespots and dorsolateral longitudinal row of 59-84 teeth, each of which is crowned with 4 - 1 2 , minute, outcurved spines, total number of teeth varying from 133 to 163. Frontal lobe 0.4-0.7 mm wide, with shallow median indentation or two submedian indentations. Prohaptor saucer-

38

shaped, 0.5-0.76 X 0.4-0.62 mm. Opisthohaptor circular, 1.25-1.85 X 1.221.7 mm, with a finely scalloped marginal membrane 0.1-0.15 mm wide; ventral surface not papillate, divided by seven septa into seven marginal triangular loculi and a central loculus which is open posteriorly and separated from medioposterior loculus by a transverse septa, at each outer end of which is a blunt-pointed, slender, nearly straight anchor 80-110 ¡i long. Mouth aperture immediately behind eyespots. Pharynx muscular, with distinct postequatorial constriction, 0.4-0.6 X 0.3-0.68 mm. Ceca with dendritic outer and inner branches, united posteriorly anterior to opisthohaptor. Testes follicular, 80-110 in number, entirely confined to interintestinal field. A number of Goto's glands scattered among testes. Vas deferens forming a long transverse loop immediately in front of transverse vitelline duct and vitelline reservoir, then winding forward medial to vagina, crossing uterus and cirrus pouch dorsally, finally penetrating cirrus pouch at its base to lead into comparatively wide (28 in the type) ejaculatory duct. Prostatic cells extending transversely along anterior margin of transverse loop of vas deferens; prostatic ducts bundled together and emptying into prostatic reservoir at base of cirrus pouch. Prostatic reservoir elongate or elliptical, 90-170 X 40-70 n, alongside proximal portion of ejaculatory duct. The narrow duct from this prostatic reservoir unites with the attenuated distal end of the ejaculatory duct at the base of the cirrus. Cirrus pouch short, claviform, posterosinistral to pharynx, 0.18-0.26 X 0.080.13 mm, with rather weak wall of longitudinal muscles. Cirrus elongate, cylindrical, papillated, 0.16-0.23 m m l° n § by 35-60 wide, projecting into genital atrium which opens ventrally to left of pharynx a little away from left body margin.

DISCUSSION

Ovary subglobular, median, 0.25-0.42 X 0.28-0.5 mm, at posterior end of anterior third of body. Ootype between cirrus pouch and winding vas deferens, containing one shrunken egg in the type; uterus opening into genital atrium at level of base of cirrus; eggs one at a time, rectangular, 0.1 X 0.1 mm in life, with rigid filament 50-70 ¡i long at each corner. Vitelline follicles small, co-extensive with intestine and its branches, extending into intertesticular space as well as into base of frontal lobe where they are confluent medianly. Vitelline reservoir oval, 0.1-0.15 X 0.19-0.25 mm. Vagina thick-walled, opening ventrally at the point where the uterus opens into the genital atrium; vaginal duct thin-walled, spirally twisted just before forming oval to elliptical seminal receptacle 0.15-0.21 mm long by 0.11-0.15 mm wide and lying anterosinistral to vitelline reservoir, from which the receptacle is separated by the vas deferens. This species differs from the most closely related Capsala (Caballerocotyla) biparasitica (Goto, 1894) Price> ^^o in possessing a definitely larger opisthohaptor, and from Capsala nozawae (Goto, 1894) Price, 1938 in possessing a single row of dorsolateral marginal teeth and an opisthohaptor which is non-papillate ventrally.

Capsaiidae

17 HABITAT

DESCRIPTION

DISCUSSION

Capsala nozawae (Goto,

1894)

Price,

1938

39

FIGURE 1 7

Gills of ParathuTiniis sibi, Thunnus alalonga, Acanthocybium solandri and on caligoid copepod parasitic in buccal cavity of Neothunnus macropterus; Hawaii. (Based on 2 5 whole mounts.) Body approximately elliptical in outline, 3 . 4 5 - 1 2 mm in length including opisthohaptor, 1 . 5 - 6 . 0 mm in maximum width in midregion. Opisthohaptor 1 . 1 - 2 . 7 x 1 0 - 2 - 8 mm, fringed with scalloped marginal membrane and provided with uniformly distributed, cuticular papillae on ventral surface which is divided by seven septa into seven marginal areolae and a central areola, the latter being produced backward and provided on the septum at its posterolateral corner with an anchor which is 0 . 1 - 0 . 1 6 mm long and pointed anteriorly. Prohaptor oval, 0 . 3 3 - 1 . 3 X 0 . 4 - 1 . 1 mm; frontal lobe truncate, 0 . 4 7 - 1 . 7 mm wide, containing intestinal branches and vitelline follicles except in marginal area. Two pairs of eyespots rudimentary in region of cephalic ganglia. Pharynx with conspicuous equatorial constriction, 0 . 2 7 - 0 . 9 X 0 . 3 2 - 0 . 9 mm in the specimens from Parathunnus and Thunnus, but 1 . 2 - 1 . 2 4 X 1 . 2 5 mm in two specimens from Acanthocybium. Intestinal limbs with numerous ramified outer branches, apparently confluent posteriorly. Testes subglobular to oval, 1 0 0 - 2 6 0 in number, usually confined to interintestinal field, although occasionally some of them may be outside of the intestinal limbs as shown in Goto's original figure. A number of Goto's glands scattered among testes. After passing along the vitelline reservoir the vas deferens becomes swollen and turns back on itself in front of the ovary and then becomes convoluted anterior to the vitelline reservoir; it penetrates the cirrus pouch at its base. Cirrus pouch pyriform, 0 . 1 6 - 0 . 5 5 X 0.08-0.4 m m ; prostatic reservoir 0.08-0.28 X 0 . 0 4 - 0 . 2 3 m m - Prostatic cells largely clustered around preovarian vas deferens coils; their ducts bundled together, running obliquely forward and penetrating cirrus pouch at its base. Cirrus rather slender. Common genital pore to left of pharynx at level of pharyngeal constriction. Ovary subglobular, 0 . 1 - 0 . 6 5 X 0 . 1 3 - 0 . 9 mm, median, in posterior half of anterior third of body or at junction of two anterior thirds. Eggs rhomboid, 0.1 X 0.1 mm in life, with filament about 70 ¡x long at each angle. Vagina thick-walled, opening ventrally just posterior to genital pore. Seminal receptacle rounded, 0 . 1 1 - 0 . 3 2 mm in diameter, posterolateral to convoluted vas deferens. Vitellaria co-extensive with intestinal branches; collecting ducts of the two sides confluent posteriorly, completely bordering testicular area, sending inward a number of narrow branches which are ramified in the space among the testes, so that the intertesticular space is filled with many vitelline follicles and a number of Goto's glands. Vitelline reservoir 0 . 0 4 - 0 . 2 3 X 0 . 0 6 - 0 . 3 7 m m > immediately preovarian. It is interesting to note that the pharynx in the specimens from Acanthocybium solandri is much larger than that in other specimens and that the

4°

dorsomarginal armature is entirely absent in the present species, whereas the papillae on the septa and areolae of the opisthohaptor are very conspicuous. 18 HABITAT

Capsala ovalis (Goto,

1894)

Price,

1938

FIGURE 1 8

Gill plates of Makaira audax, M. ampla, Tetrapterus angustirostris, Istiophorus orientalis and Istiompax marlina; Hawaii. This species was found by Goto in the mouth cavity of Histiophorus sp. from Japan and described with excellent illustrations. Goto failed to show, however, the conspicuous papillae on the ventral side of the body, especially on the postpharyngeal ventral surface, the papillated cirrus, the dorsal submarginal row of teeth, and the regular crenulation of the marginal haptoral membrane. The central areola of the opisthohaptor extends backward between two anchors, but there is a transverse ridge between its central portion and its posterior extension, though it is not shown in Goto's figure. The larger dorsal submarginal teeth, each of which bears 2-5 pointed divergent denticles, are arranged in one arcuate row, 14-32 on one side, making a total of 3 3 - 5 4 on both sides. On the left side there is a straight or zigzag pre-equatorial longitudinal row of smaller teeth just outside of the row of the larger teeth; the number of them is, however, very variable, and may be as many as 36. The following measurements are from 28 whole mounts: Body 7-13 X 5-11 mm, opisthohaptor 1 . 9 - 4 . 1 mm in diameter, haptoral anchors 0 . 4 7 0.84 mm long, pharynx with very conspicuous lateral constriction, 0.81 . 6 X 0 . 8 - 1 . 4 5 mm, vitelline reservoir oval, 0 . 2 - 0 . 6 X 0 . 2 3 - 0 . 6 5 mm, ovary 0.5-1.2 X 0.95-1.9 m m .

19 HABITAT

Capsala (Caballerocotyla) biparasitica (Goto,

1894)

Price,

i 9 6 0 FIGURE 1 9

Dorsal surface of a caligoid copepod parasitic on Neothunnus macropterus and Parathunnus sibi; Hawaii. Iversen and Hoven ( 1 9 5 8 ) found this species on Neothunnus micropterus from Christmas Island. The following measurements are from nine whole mounts. Body 3 . 9 - 7 . 0 X 1 . 5 - 3 . 5 m m - Opisthohaptor 0 . 6 4 - 0 . 9 mm in diameter, with scalloped marginal membrane; radial septa not distinct, although there is a deep central loculus which is produced backward to the level of the anterior end of paired anchors; anchors 7 0 - 1 0 0 ¡x long, divided posteriorly into two blunt unequal branches, with a nodular thickening near base of its pointed anterior claw. Along the dorsolateral margin of the body is a long longitudinal row of small sclerotized teeth crowned with a circle of several (usually up to 12), outcurved spines; it extends from the level of the pharynx to near the opisthohaptor; the number of teeth varies from 58 to 77 on the right, from 70 to 79 on the left, totaling

Capsalidae

DISCUSSION

KEY TO SPECIES OF

Capsala FROM HAWAIIAN FISHES

41

128-155 on both sides in nine specimens. Prohaptor oval, saucer-shaped, 0.45-0.64 mm long; head lobe between two prohaptors broadly flattened at apex, with a pair of anterior-most cecal branches obscured by surrounding vitelline follicles. Two pairs of small eyespots present. Pharynx constricted behind middle, 0.32-0.73 X 0.33-0.8 mm. Intestinal limbs with inner and outer subdivided branches, apparently confluent immediately in front of opisthohaptor. Testes rounded to polygonal, paved in one layer in postovarian interintestinal field, but not reaching opisthohaptor; their exact number could not be made out, but probably there are at least 65-90, possibly over 100. Vas deferens forming a very conspicuous transverse loop immediately in front of ovary and vitelline reservoir. Cirrus pouch claviform, 0.25-0.7 X 0.1-0.15 m m > posterolateral to pharynx, containing at its basal swelling a twisted prostatic reservoir and winding ejaculatory duct; prostatic cells distributed mostly in front of vas deferens loop, and their ducts converging toward base of cirrus pouch. Cirrus cylindrical, densely papillate. Genital pore posterior to left prohaptor. Ovary irregularly ovoid, indented, at junction of anterior with middle third of body. Ootype between base of cirrus pouch and vas deferens coils. Uterus opening into genital atrium near distal end of cirrus pouch. Eggs about 100 X 90 fi, with four short filaments, of which one is on the opecular pole, another on the opposite pole, and the other two are lateral. Vitellaria co-extensive with intestinal limbs and their branches; vitelline reservoir pressed against ovary on its anterosinistral side, 0.08-0.18 X 0.120.25 mm. Vagina opening just at the point where the uterus opens into the genital atrium. Receptaculum seminis vaginae large, 0.13-0.27 X 0 . 1 0.18 mm, situated to left of median line immediately in front of vas deferens loop, across which it is connected with the vitelline reservoir by a narrow seminal duct. Caballerocotyla Price, i960 is treated in my Systema Helminthum Vol. I V and the present monograph as a subgenus of Capsala because there is no great difference in internal anatomy. Capsala was separated by Price (i960) from Caballerocotyla because the testes of the former extend laterad beyond the intestinal trunk, but as shown in Capsala nozawae (Goto, 1894), the lateral extent of the testes is not as important as the structural difference in the terminal genitalia. In Capsala and Caballerocotyla the terminal genitalia are quite similar.

Opisthohaptor not papillated ventrally; marginal teeth complex; intertesticular vitelline follicles not well developed: 2 Opisthohaptor papillated ventrally; marginal teeth simple when present, or absent; intertesticular vitelline follicles profusely developed: 4 Haptoral anchor with subapical thickening; opisthohaptor comparatively small; cirrus papillate: C. biparasitica Haptoral anchor without subapical thickening; opisthohaptor large: 3

4a

3 Body, especially postpharyngeal area, with ventral cuticular papillae; marginal teetn with accessory rows, each with 4 or 5 spines; cirrus papillate: C. ovalis Body without ventral cuticular papillae; dorsomarginal teeth without accessory rows, each with spinose crown; cirrus papillate: C. neothunni 4 Body elongate; marginal tooth absent; opisthohaptor moderately large; cirrus rather slender, smooth: C. nozawae Body oval to elliptical; marginal tooth with a simple spine; opisthohaptor rather small; cirrus smooth: C. gotoi 20 HABITAT HOLOTYPE DESCRIPTION

Capsaloides cristatus n. sp.

FIGURE 20

Gills of Makaira sp. (type host) and Tetrapterus angustirostris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 98. (Based on 20 whole mounts.) Body plate-like, pyriform to circular in outline, 7 - 1 2 X 4 . 3 - 1 0 mm, with more or less frilled margins and a shallow median notch posterior to opisthohaptor. This notch, however, is not so pronounced as in Capsaloides sinuatus (Goto, 1 8 9 4 ) . Dorsomarginal crests 2 4 - 4 1 on one side, totaling 5 5 - 7 3 on both sides, each with sclerotized base, fringed with minute spines. They are in one longitudinal row, well developed anteriorly, but more or less weakly developed posteriorly; on the posterior margin of the body they are replaced by flat elevations devoid of sclerotized base and/or crown-shaped top, and simply covered with minute spines. On each anterolateral margin of the body there is an isolated longitudinal row of 4-10 smaller comb teeth. Opisthohaptor oval in outline, 1 . 0 - 1 . 8 5 X 1 . 0 - 1 . 9 mm, with scalloped marginal membrane up to 0 . 1 6 mm wide, divided by seven radial septa, of which the posterior septum is bifid distally. Haptoral anchor 0 . 1 4 - 0 . 2 4 m m l°n§> with a small claw-like point, a prominent guard, and a long, stout root or shaft. Prohaptor saucer-shaped, 0 . 5 - 1 . 0 5 mm in transverse diameter, composed of radial columns of small glandular cells intercalated among numerous muscle bundles radiating from the central base. Frontal lobe truncate, trapezoidal. Two pairs of widely separated eyespots at level of oral aperture. Mouth wall provided with circular muscles; pharynx approximately quadrate, muscular, 0 . 5 5 - 0 . 9 X 0 . 5 8 - 1 . 0 5 mm, with funnel-shaped lumen; esophagus short, 0.3 mm long by 0.35 mm wide in the type 11 mm long. Intestinal crura with dendritic outer, and few inner, branches, confluent behind testes, posterior branch reaching posterior extremity of body; first outer branches from the two sides extending into the median preoral lobe approach each other between the two prohaptors; first inner branches with short side branches pass inward between the ovary and the right or left testis and then curving outward intrude into the space between the median and lateral testes, apparently communicating with the posterior inner branches, so that the testes, 8 0 - 1 2 0 in number and confined to the interintestinal area in the midregion of the body, are divided by the inner intestinal branches into one median and two laterals in form of letter W .

Capsalidae

DISCUSSION

21 HABITAT HOLOTYPE DESCRIPTION

43

Vas deferens forming a transversely elongated loop in front of ovary and vitelline reservoir and convoluted between ootype and receptaculum seminis vaginae. Ejaculatory duct penetrating cirrus pouch at its base, running alongside prostatic reservoir and uniting with the latter at base of cirrus. Cirrus protruded into genital atrium in the type as a slender, papillate cylinder 0.4 mm long by 40 p. wide. Genital pore posterolateral to left prohaptor. Cirrus pouch claviform, 0 . 6 - 1 . 1 X 0 . 1 5 - 0 . 3 4 mm, mainly consisting of longitudinal muscle fibers, lying obliquely to left of pharynx. Prostatic cells distributed around vas deferens coils, whence their ducts converge toward the base of the cirrus pouch which they penetrate to empty into the prostatic reservoir. Prostatic reservoir elongate oval, 0.070.22 mm wide, enclosed in swollen basal portion of cirrus pouch. Ovary rounded triangular, multilobate, 0 . 0 6 - 1 . 5 X 0 . 7 - 1 . 3 5 mm, at anterior part of middle third of body. Uterus oblique, with convoluted vas deferens on the left and loose bundles of prostatic ducts on the right, opening into genital atrium at a distance of about 0.8 mm from base of cirrus pouch in the type. Eggs rhomboid, about 7 0 - 8 0 ¡x long, filament 8 0 - 1 0 0 p long. Vitellaria co-extensive with intestinal branches; vitelline reservoir 0 . 1 6 - 0 . 2 5 X 0 . 2 5 - 0 . 4 2 mm, constricted off at both ends from transverse vitelline ducts. Vagina elongate, funnel-shaped, opening ventral to left intestinal crus midway between pharynx and ovary, well provided with longitudinal muscle fibers, leading into pyriform, oval, or retortshaped receptaculum seminis vaginae 0 . 0 7 - 0 . 1 6 mm in diameter; the latter opens into vitelline reservoir by a narrow, somewhat winding, seminal duct. This species differs from Capsaloides sintiatus (Goto, 1 8 9 4 ) in the posterior sinus being much shallower. The most outstanding feature of the present species is the presence of conspicuous comb-like crests along the dorsolateral margin of the body; hence the specific name.

Capsaloides istiophori n. sp.

FIGURE 2 1

Gills of IstiophoTus orientalis (type host, local name "a'ulepe") and Makaira audax; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 99. (Based on 28 whole mounts.) Body flattened lageniform, 1 . 6 - 5 . 5 X 0 . 9 4.0 mm, produced backward into asymmetrical lobes, with a distinct median notch between. Opisthohaptor circular, 0 . 3 6 - 1 . 2 mm in diameter, with seven radial septa, of which the two posterior are bifid distally; marginal membrane scalloped, 2 0 - 4 0 ¡x wide; 1 4 marginal hooklets present; anchors 9 0 - 1 5 0 p. long, each with a claw-like blade and long stout shaft abruptly tapered at the end. Dorsolateral marginal combs extending in a longitudinal row from pharyngeal level to near posterolateral edge, 31-53 on the right, 2 5 - 5 5 o n the left, totaling 5 6 - 1 1 0 on both sides; anterior isolated group beneath right prohaptor usually rudimentary, or ab-

44

sent, up to 12 in the type; in only one specimen out of 22, fine combs were clearly seen on this side, whereas the left group which is constantly present consists of 7-14, usually 7 - 1 0 combs, each comb bearing 2-6 teeth. Frontal plate trapezoidal, with flat concave front 0.1-0.2 mm wide. Two pairs of compact eyespots present immediately in front of pharynx. Prohaptors oval, saucer-shaped; glandular cells densely massed in frontal plate and postprohaptoral areas. Pharynx muscular, barrel-shaped, 0.08-0.25 X 0.07-0.22 mm, finely papillated on its anterior margin; esophagus short; intestinal limbs with dendritic outer branches, turning inward along posterior border of testicular areas, but apparently united in median line, sending an inward branch accompanied by vitellaria. This branch unites with its fellow of the other side in form of V , thus separating the ovary from the testes; the median posterior end of this V usually not reaching the apex of the median triangular area of vitellaria in front of the opisthohaptor. Testes irregular in shape, 41-52 in total number, occupying almost entire postovarian interintestinal area, separated by the above mentioned V-shaped vitello-intestinal septum into two elongate, obliquely juxtaposed areas, giving rise to vas deferens in between. Vas deferens distended with sperm, running forward in a sigmoid curve ventral to ovary, describing a very conspicuous oblique loop on the right of median line just opposite its convoluted portion which lies medial to the left intestinal limb. The attenuated distal portion passes dorsal to the uterus and enters the cirrus pouch, where it turns back on itself and runs anterolaterad along with the attenuated distal portion of the prostatic reservoir with which it unites about halfway down the cirrus. Cirrus pouch thin-walled, variable in length and width in accordance with the state of filling of the prostatic reservoir enclosed in it; in the type it is pyriform, 93 ¡i wide, and contains a retort-shaped prostatic reservoir which is 70 /x wide and receives at its base several closely massed, elongate claviform prostatic ducts distended with secretory granules. Cirrus rod-shaped, 0.07-0.12 mm long by 20-40 /x wide, projecting into tubular genital atrium which extends to the base of the cirrus. Genital pore ventral, slightly posterior to left prohaptor at level of pharynx. Ovary rounded, irregularly lobed, 0.2-0.8 X 0.15-0.6 mm, at junction of anterior with middle third of body, bordered by main collecting vitelline duct and V-shaped vitello-intestinal system mentioned above, giving rise to germiduct at its center. The germiduct joins the duct from the vitelline reservoir ¡anterolateral to this organ, then crossing the vas deferens loop dorsally leads into the ootype surrounded by the converging ducts from the shell gland cells which are profusely distributed around the vas deferens loop on the right and also around the convoluted portion of the vas deferens on the left. The primarily rhomboid initial portion of the uterus proper may be rounded, 50-90 p in diameter, tapers into attenuated tubular distal portion which runs alongside the genital atrium and opens ventrally together with the male genital pore posterior to the left pro-

Capsalidae

DISCUSSION

22 HABITAT HOLOTYPE DESCRIPTION

45

haptor. Eggs ovoid, 90-110 X 80-90 /x, each with a curved rigid filament at the apex of a broad crescent fold extending across whole width of egg shell. Vitellaria co-extensive with intestinal limbs and their branches, confluent in front of opisthohaptor; vitelline reservoir triangular, 50—110 ¡x, long anteroposteriorly. Vagina tubular or elongated funnel-shaped, opening ventral to left intestinal limb, at level of anterior end of vas deferens loop in the type. Receptaculum seminis small, elongated retort-shaped, 50150 X 20-70 /x; seminal duct may be winding, crossing vas deferens loop ventrally and opening into apex of vitelline reservoir. This species differs from the most closely related Capsaloides tetrapteri n. sp. in that the isolated anterior group of the marginal combs is better developed and the posterior sinus is very conspicuous.

Capsaloides nairagi n. sp.

FIGURE

2a

Gills of Makaira sp. (type host) and buccal cavity of Tetrapterus angustirostris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 100. (Based on 31 whole mounts.) Body shaped like a rounded shield with shallow notch posteriorly, 6 - 1 9 X 3.5-13 mm. Dorsolateral margin of body armed with a single or double, more or less irregularly alternating row of teeth consisting of ring-shaped sclerotized base and a semicircular crown of minute saw-like denticles. These crown-shaped teeth are, however, completely lacking on frontal lobe and posterior terminal notch. The number of the teeth varies from 154 to 352 on one side, most commonly between 216 and 295, totaling 312-646 on both sides. In addition to these teeth there is an isolated anterior row of 5 - 1 8 smaller teeth. Opisthohaptor 1.2-3.1 mm in transverse diameter, with regularly scalloped marginal membrane, divided by seven septa, each posterior septum being bifid distally. Haptoral anchor 0.11-0.28 mm long, with small claw-like point, a swollen guard, and a long stout shaft. Prohaptor elliptical in outline, glandulomuscular, with central pit, 0.9-1.6 mm in transverse diameter. Two pairs of eyespots wide apart at level of mouth aperture. Pharynx rounded, strongly muscular, 0.5-1.2 X 0.55-1.2 mm. Esophagus short; intestinal limbs confluent posteriorly, with several dendritic outer branches terminating near body margin and two inner branches, each of which arises lateral to the ovary and takes a sigmoid course between ovary and testes and between median and lateral testes and may or may not join the posterior intestinal arch submedianly. Testes 50-85 in number, in equatorial region, divided into a small median and larger reniform lateral areas, W-shaped in pattern, but these areas may be continuous when the inner intestinal branches are discontinued posteriorly. Vas deferens forming a conspicuous transverse loop in front of vitelline reservoir and then convoluted between uterus and receptaculum seminis vaginae, finally turning anterolaterad to take a straight

46

course toward base of cirrus pouch which it penetrates along with the prostatic ducts; ejaculatory duct narrow, uniting with prostatic duct at base of cirrus. Cirrus pouch claviform, 0.8 X 0.15 mm in the type, provided with inner longitudinal and outer circular muscle fibers, situated obliquely to left of pharynx, with its base not reaching left intestinal limb. Cirrus slender, telescoped into distal end of cirrus pouch in the type. Genital pore beneath outer end of left prohaptor. Prostatic cells mainly distributed between transverse loop of vas deferens and ovary and around convoluted vas deferens, their efferent ducts running parallel to one another along straight distal portion of vas deferens and opening into prostatic reservoir enclosed in cirrus pouch; prostatic reservoir formed by dilatation of proximal portion of prostatic duct, about 60 ¡x wide in the type. Ovary 0.45-1.5 X 0.45-1.9 mm, rounded triangular, coarsely lobed in form of a rosette, at anterior part of middle third of body. Uterus claviform, oblique, opening into genital atrium near distal end of cirrus pouch. Eggs rhomboid, 60-80 X 50-60 ¡i, filament 0.1-0.15 m m l°ng- Vitellaria co-extensive with intestinal limbs and their branches; vitelline reservoir oval or bean-shaped, 0.11-0.33 X 0.18-0.47 m m > transversely immediately in front of left portion of ovary, giving rise to efferent duct at its right anterior corner. Vagina funnel- or goblet-shaped, opening ventrally just lateral to left intestinal limb at level of intestinal bifurcation; receptaculum seminis vaginae pyriform or retort-shaped, 0.14-0.4 X 0.110.23 mm. DISCUSSION

23 HABITAT

DESCRIPTION

This species differs from the most closely related Capsaloides cristatus n. sp. in the number and structure of the dorsolateral teeth. The specific name refers to the Japanese collective local name for the istiophorid hosts. Capsaloides sinuatus (Goto, 1894) Price, 1938

FIGURE 23

Gills of Makaira audax (local name "kajiki"); Hawaii. (Based on five whole mounts.) Body approximately circular, 13-17 X 13.3-17.5 mm, with a distinct median notch posteriorly. Frontal plate 1.0-1.5 mm wide, flat or concave; lateral edge sinuous, papillate, with rise and fall at comparatively regular intervals, each rise bearing a comb dorsally; number of combs varying from 50 to 62 on one side, 113-126 in total for each individual; each comb with 1-20 spiniform teeth. Prohaptor oval, 1.15-1.4X0.09-1.37 mm. Opisthohaptor circular, never projecting backward beyond posterior notch, 2-3 mm in diameter with five, simple, and two, distally bifid septa and scalloped marginal membrane 0.2 mm wide; central area produced backward. Anchor with small claw-like tip, 0.15-0.21 mm long. Two pairs of eyespots anterodorsal to mouth aperture. Pharynx rounded, without lateral constriction, 0.7-1.0 X 0.85-1.18 mm. Postpharyngeal gland cells well developed, their ducts converging toward posterior end of pharynx, whence they are directed forward to open into

Capsalidae

47

the lumen of the pharynx. Esophagus very short; intestinal limbs sending off numerous dendritic outer branches reaching to marginal area of body and a few coarsely subdivided inner branches which intrude into the intertesticular space, partly anastomosing with the fellows from the other side. Posteriorly the two intestinal limbs join together anterior to the opisthohaptor. Testes numerous, closely packed in one layer, bordered by main intestinal limbs, separated anteriorly from ovary by inner intestinal branch; their number could not be determined. Vas deferens running forward beside ovary, forming transverse loop in front of transverse vitelline duct and then thrown into convolutions medial to left intestinal limb, finally crossing uterus dorsally and turning back on itself before entering cirrus pouch. Cirrus pouch thin-walled, 0.2-0.25 mm in diameter, containing elongate retort-shaped prostatic* reservoir 0.1-0.17 mm in diameter, the attenuated distal portion of which runs through the cirrus and unites with the latter near the apex of the cirrus. Prostatic cells divided into two groups, as is evident from the fact that there are two distinct bundles of collecting ducts; one larger bundle coming from the right side enters the cirrus pouch at its base, whereas the other smaller bundle consisting of four ducts coming from the left side turns back on itself at the point of flexion of the vas deferens and penetrates the cirrus pouch sideways at the level of the swollen base of prostatic reservoir. Prostatic cells are distributed profusely among the vitelline follicles both inside and outside of the intestinal limbs in the zone between the prohaptors and the ovarian level; their cytoplasmic granules can be easily distinguished from the yolk granules by their lighter color in the well differentiated hematoxylinstained specimens. Just outside the intestinal limbs at the level of the ootype and uterus the gland cells are more numerous than the yolk cells. Cirrus gradually tapered, 0.32-0.55 X 0.12-0.18 mm, enclosing ejaculatory duct and prostatic duct at its greater proximal part. Genital atrium tubular, long, reaching base of cirrus, opening separately from uterine pore immediately below posterior end of prohaptor. Ovary rounded, multilobed peripherally, 1.15-1.6X1.65-2.5 mm, median, immediately pretesticular, bordered by inner branches of intestinal limbs, ascending vas deferens and transverse vitelline ducts. Germiduct arising from center of ovary, uniting with short transverse duct from vitelline reservoir and then entering ootype, from which shell gland ducts radiate. Shell gland cells are intermingled with prostatic cells mentioned above, and are hardly distinguishable from the latter cells except that their cytoplasmic granules stain darker. Uterus running obliquely forward along genital atrium and opening independently a little posteromedial to male pore. No eggs observed. Vitellaria co-extensive with intestinal limbs and their branches except for anterior extremity. In this area the compact gland cells containing rather coarse granules deeply stainable with hematoxylin are densely massed around the intestinal branches, in the prohaptors and immediately behind them. Vitelline reservoir ovoid, 0.27-

48

DISCUSSION

24 HABITAT HOLOTYPE DESCRIPTION

0.5 mm anteroposteriorly and 0.42-0.7 mm transversely, between ovary and transverse vas deferens loop, receiving seminal duct at its anterior end. Vagina opening ventrally outside of left intestinal limb at or just behind level of intestinal bifurcation. Receptaculum seminis vaginae elongate pyriform, 50-90 ¡t, wide, lateral or ventral to left intestinal limb, with a small sphincter between itself and vagina; seminal duct comparatively long, descending windingly dorsal to convoluted vas deferens. The above detailed account is intended to supplement Goto's rather brief description. His excellent original figure is reproduced in my Systema Helminthum Vol. IV (PI. 26, Fig. 205). The specific name sinuatus should be sinuata grammatically, because the compound generic name is feminine in gender according to the conventional grammatical rule, but according to the latest London decision of the International Commission of Zoological Nomenclature, any compound generic names ending with oides should be masculine in gender; therefore the specific name was changed from sinuata to sinuatus.

Capsaloides tetrapteri n. sp.

FIGURE

24

Gills of Tetrapterus angustirostris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 101. (Based on 26 whole mounts.) Body flattened lageniform, 1.7-3.8 X 0.5-1.9 mm, produced backward into symmetrical lobes, between which is a median notch. Opisthohaptor disc-shaped, 0.25-0.6 mm in diameter, usually projecting backward beyond body proper, with scalloped marginal membrane and 14 marginal hooklets 1 3 - 1 6 ¡j. long, attached to body proper just in front of median notch by a short stalk up to 120 ¡x wide; seven septa radiating from central areola which is produced backward; each of posterior septa bifurcating distally; haptoral anchor 80-140 ¿1 long, with clawlike tip and strong shaft abruptly tapered at the end. Dorsolateral marginal combs extending in a single longitudinal row from pharyngeal level to posterolateral edge of posterior lobes, 25-57 o n the right, 26-56 on the left, making a total of 5 1 - 1 1 3 on both sides; each with 2 - 1 1 marginal teeth; anterior group of smaller combs isolated beneath prohaptor consisting of up to 7 (mostly 2-5) combs with 2-7 teeth each on the left (absent in only one specimen out of 23); on the right, however, the combs are rudimentary or absent, 1 - 5 when present, each with 2-5 teeth. Frontal at plate trapezoidal, 0.1-0.15 m m ^s flat or concave margin; prohaptor oval, saucer-shaped, 0.13-0.22X0.09-0.15 mm, containing abundant glandular cells which extend into the frontal plate as well as into the area immediately posterior to prohaptors. Two pairs of compact eyespots anterodorsal to pharynx. Pharynx muscular, 0 . 1 2 - 0 . 2 4 x 0.08-0.27 m m > finely papillated along its anterior margin; esophagus tubular, 30-60 X 20-60 n; intestinal limbs with numerous subdivided outer branches, of which the posterior reach to the margin of the posterior lobes; the two

Capsalidae

DISCUSSION

49

limbs curve inwards posteriorly and unite with each other medianly anterior to the opisthohaptor. Testes irregular in shape, 24-48 in number, occupying entire postovarian interintestinal field in form of inverted V shape. Vas deferens forming a sigmoid curve ventral to ovary and then forming an oblique loop on the right of median line opposite its narrower, convoluted, distal portion. This portion, after crossing the uterus dorsally, enters the cirrus pouch, in which it turns back on itself and finally joins the prostatic duct in the proximal portion of the cirrus. Cirrus pouch thin-walled, variable in length, 46 ¡x wide in the type, containing small, retort-shaped prostatic reservoir 30 p wide in the type. Cirrus cylindrical, 0.09-0.15 mm long by 15-25 /t wide at base, projecting into genital atrium for its entire length, sometimes out of genital pore. Genital atrium tubular, reaching to base of cirrus, opening ventrally a little below left prohaptor at level of pharynx. Ovary rounded, rather multilobate, 0.15-0.55 X 0.1-0.4 mm, pre-equatorial, bordered by two intestinal limbs laterally and by transverse vitelline duct anteriorly, in direct contact with testes posteriorly, giving off germiduct at about its center. The germiduct joins the duct from the vitelline reservoir at the level of the apex of the vitelline reservoir to be continued into a narrow duct surrounded by shell gland cells. Initial portion of uterus proper primarily rhomboid, but may be rounded, 50 ¡t. wide in the type, gradually narrowed into tubular distal portion which runs obliquely forward close parallel to the genital atrium and opens ventrally immediately behind the male pore. Eggs one at a time, rounded to elliptical, 90-140 X 70-80 ¡1, with a small outbulging near its broader pole; filament rigid, up to about 70 ¡x long. Vitellaria co-extensive with intestinal limbs and their branches; main collecting vitelline ducts confluent at point of union of intestinal limbs, running forward along inner side of intestinal limbs, giving off a small inner branch which separates the ovary from the testes on the right (this branch is very variable in development and may occasionally be absent), united immediately in front of ovary to form a triangular reservoir which is 60-140 ¡x long anteroposterior^; in the type its apex is bent toward the left to join the seminal duct from seminal receptacle and gives off its efferent duct from the convex right margin. Vagina tubular, opening ventral or just lateral to left intestinal limb at level of cirrus pouch; seminal receptacle claviform, 50-70 X 18-30 p, connected with apex of vitelline reservoir by a narrow seminal duct crossing vas deferens loop ventrally. This species very closely resembles Capsaloides perugiai (Setti, 1898) Price, 1938, from Tetrapterus belone of the Mediterranean, in body shape and internal anatomy, but since the latter species has only been inadequately described, it is impossible to make a detailed comparison of the two species. On the other hand, the present species bears a close resembalance to Capsaloides istiophori n. sp., only differing in the posterior sinus being inconspicuous and in the opisthohaptor being attached ventral to the sinus.

5°

KEY TO SPECIES OF

Capsaloides FROM HAWAIIAN FISHES

25 HABITAT HOLOTYPE DESCRIPTION

Posterior sinus conspicuous; no isolated group of marginal combs: C. sinuatus Posterior sinus conspicuous; isolated anterior group of marginal combs present: C. istiophori Posterior sinus inconspicuous; isolated anterior group of combs present: 2 Marginal combs in a zigzag or double row: C. nairagi Marginal combs in one simple row: 3 Opisthohaptor anterior to sinus; testicular area W-shaped: C. cristatus Opisthohaptor ventral to sinus; testicular area inverted V-shaped: C. tetrapteri Tristoma adcoccineum n. sp.

FIGURE 2 5

Gills of Xiphias gladius; Hawaii. U.S. Nat. Mus. Helm. Coll, S.Y. No. 102. (Based on 14 whole mounts.) Body strongly flattened oval, 10-19 x 7 - 1 5 mm, with numerous, rounded papillae easily recognizable with the naked eye and scattered over the dorsal surface, especially posterior to testicular area; posterior papillae larger and more numerous than the anterior. Transverse marginal rows of combs consisting of several, usually 3 or 4, denticles, of which the outermost one or two are serrate on the concave apex, others being 1 - 2 cuspid at the tip as illustrated by Price ( 1 9 3 9 ) for num Tristoma coccineum; comb teeth 6 7 - 9 9 b e r on each side, totaling 1 4 4 - 1 9 4 on both sides, lacking on cephalic lobe and in posterior sinus. Opisthohaptor muscular, with scalloped marginal membrane, 1 . 7 5 - 4 . 0 X mm 1.6-3.9 > divided by seven, muscular, distally pointed septa into seven triangular areolae and a heptagonal central areola, the latter produced backward to near paired haptoral anchors; anchor simple, pointed anteriorly, 0.12-0.15 mm long. Prohaptor saucer-shaped, oval in outline, 1.02.0 X 1.0-2.1 mm, glandulomuscular. Frontal lobe truncate in front, containing anteriormost intestinal branches surrounded by vitellaria. Two pairs of eyespots anterodorsal to mouth aperture. Mouth bordered by strong circular muscles, opening at level of posterior end of prohaptors. Pharynx bowl-shaped, strongly muscular, without constriction, 0 . 9 - 1 . 4 X mm 1.0-1.7 > pharyngeal gland ducts convergent toward posterior end of pharynx; pharyngeal gland cells well developed posterolateral to pharynx. Esophagus very short, main intestinal limbs united posteriorly in anterior part of posterior third of body a short distance anterior to opisthohaptor, with subdivided inner and outer branches; inner branches arising at level of ovary much stronger than others, continuous with each other behind ovary as well as with branches arising from posterior cecal loop; outer branches more strongly ramified than inner. Testes rounded or irregular in shape, very numerous, arranged in one layer in postovarian interintestinal area, measuring as a whole 3.4-5.9 X 3.5-6.3 mm. Vas deferens passing by left side of ovary, describing a transversely elongate loop in front of transverse vitelline duct, and then con-

CapsaJidae

DISCUSSION

26 HABITAT HOLOTYPE DESCRIPTION

51

voluted medial to seminal receptacle, crossing uterus dorsally, penetrating cirrus pouch, finally leading into ejaculatory duct. Cirrus pouch bulbous, 0 . 3 7 - 0 . 5 X 0 . 2 3 - 0 . 3 5 mm, provided with well developed longitudinal muscles which are continued further medioposteriad beyond base of the pouch as parallel bundles, containing prostatic reservoir at base and convoluted ejaculatory duct distally. Prostatic ducts bundled, running obliquely backward from base of cirrus pouch which they penetrate; prostatic cells distributed in vicinity of vas deferens loop as well as among testicles, though not so numerous in latter area as in Tristoma adintegrum which is to be described below. Ovary multilobed in a rosette form, 0 . 7 5 - 2 . 0 X 0 . 8 8 - 1 . 6 mm, situated in median line at posterior part of anterior third of body, giving off germiduct in its center. Germiduct joining a short duct coming from right dorsal end of vitelline reservoir and surrounded by numerous convergent shell gland ducts just before leading into ootype. Shell gland cells distributed mainly in vicinity of vas deferens coils. No uterine eggs observed. Uterus extending along genital atrium and opening a little posterior to genital pore. Vagina opening ventrally posterior to uterine pore; vaginal duct well provided along its straight distal portion with longitudinal muscles which extend further backward over the winding proximal portion and receptaculum seminis vaginae. Seminal receptacle elongate, 0 . 3 - 0 . 5 5 X 0 . 1 - 0 . 1 7 mm, connected with left end of vitelline reservoir by a narrow, nearly straight duct, enclosed in a sheath of longitudinal muscles. Vitellaria co-extensive with intestinal branches; vitelline reservoir subglobular to oval, 0 . 1 3 - 0 . 3 3 X 0 . 1 6 - 0 . 7 m m > w ^ h thick walls of longitudinal muscle fibers, situated immediately anterior to left part of ovary. Our Hawaiian specimens agree well with the redescription given by Price ( 1 9 3 9 ) for Tristoma coccineum from the Atlantic (Woods Hole) swordfish except in the number of the dorsomarginal rows of comb teeth ( 6 7 - 9 9 vs. 4 3 - 5 4 ) . This difference appears to be of specific importance, so the Hawaiian species is regarded provisionally as distinct from the Atlantic, until as many comb teeth are observed in the Atlantic specimens as in the Hawaiian specimens. In view of the limited range of variation in the number of rows of comb teeth, Tristoma coccineum of Bychowsky ( 1 9 5 7 ) must have been misidentified (cf. Systema Helminthum Vol. IV, PL 26, Fig. 2 0 4 ) .

Tristoma adintegrum n. sp.

FIGURE 2 6

Gills and buccal cavity of Xiphias gladius; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 0 3 . (Based on five whole mounts.) Body flattened oval, slightly convex dorsally, with very slight constriction on lateral margins at level between pharynx and testes, 16-22 mm in length, with maximum width of 14-20 mm in posterior testicular zone. Dorsal papillae observed in small number

52

along posterior and lateral margins. 330-440 transverse rows of dorsomarginal comb teeth were counted, each row consisting of 1 - 7 teeth arranged in close succession or separately (most posteriorly), each tooth bearing 4-8 denticles. Frontal plate trapezoidal, 1.8 mm wide in the type, containing intestinal branches and vitellaria except in marginal area; posterior marginal notch inconspicuous. Opisthohaptor disc-like, not exactly reaching medioposterior marginal notch, 3.0-4.4 X 3.5-4.3 mm, surrounded by pleated membrane, without ventral papillae; central area rather circular, with seven septa radiating from it; haptoral anchors 0.15 mm long. Prohaptor foliate, oval in outline, 1.7-2.0 X 2.0-2.4 mm. Mouth aperture between two prohaptors, with two pairs of minute eyespots anterodorsally. Pharynx subglobular, without constriction, 1 . 1 - 1 . 4 X 1.31.8 mm. Pharyngeal gland ducts convergent toward posterior end of pharynx. Intestinal limbs united posteriorly, sending out a number of branches, of which the outer are dendritic and reach to the body margin; some of the inner branches are united with one another, forming intertesticular network. Testes very numerous, irregularly lobulate, confined to interintestinal field; in the space among the testes there are, in addition to the intestinal branches accompanied by yolk cells, scattered oval cells definitely smaller than the yolk cells and containing cytoplasmic granules different from yolk granules. I prefer to regard these cells as prostatic cells, though no connection with the prostatic ducts could be detected. Vas deferens formed behind ovary by union of two or three main vasa efferentia, passing forward by left side of ovary, forming transversely elongated loop immediately in front of transverse vitelline duct and then convoluted just medial to seminal receptacle; in the cirrus pouch it is still convoluted until it finally unites with the prostatic duct. Cirrus pouch subelliptical, muscular, 0.6-1.0X0.35-0.4 mm, containing spherical prostatic reservoir at its base; cirrus smooth, subcylindrical, muscular, projecting into genital atrium and reaching to genital pore opening dorsal to left prohaptor anterior to pharyngeal level. Genital atrium extending from genital pore to base of cirrus. Prostatic ducts running close together with strong muscle bundles which are continued inward from the wall of the cirrus pouch. Ovary rosette-shaped, 1.7-2.4X1.6-2.0 mm, with clear central area, from which the germiduct arises. The germiduct may be swollen and convoluted at the origin; it passes forward to and joins the duct from the vitelline reservoir. Shell gland ducts are convergent toward the proximal end of the ootype. Uterus opening a short distance posterior to genital pore. No eggs observed. Vitellaria co-extensive with intestinal branches; vitelline reservoir rounded, 0.22-0.32 X 0.25-0.4 mm. Vagina somewhat funnel-shaped, opening ventrally lateral to uterus at level of pharynx; vaginal duct winding proximally, with muscular coat; receptaculum seminis vaginae elongate, 0.4-1.0 X 0.16-0.22 mm, between left intestinal limb and convoluted vas deferens, opening into vitelline reservoir by a narrow, winding seminal duct.

Capsalidae

DISCUSSION

27 SYN. HABITAT DESCRIPTION

53

This species resembles Tristoma integrum Diesing, 1850 of Taschenberg (1879), though it is much larger than that of Price (1939), but differs from the latter species notably in the following points: (1) dorsal papillae, when present, are limited to the posterior and posterolateral areas alone; (2) dorsomarginal comb teeth with 4-8 denticles instead of 3-5, each row comprising 1 - 7 teeth as compared with 6 (usually); and (3) central area of opisthohaptor circular instead of heptagonal. On the basis of these differences, I venture to separate the Hawaiian species from T. integrum, naming it Tristoma adintegrum n. sp. T. coccineum of Bychowsky (1957) may be identical with the present species because of the enormous number of the marginal rows of comb teeth and the circular central area of the opisthohaptor, although the uterus in T . adintegrum is shown to open beside the male genital pore. It is to be noted that the prostatic cells were found among the testicles. In this connection, Dioncopseudobenedenia Yamaguti, 1965 is recalled, since the prostatic cells are distributed profusely among the vitelline follicles in that genus.

Nasicola klawei (Stunkard, 1962) n. comb. Caballerocotyla klawei Stunkard, 1962

FIGURE

27

Nasal cavity of Neothunnus macropterus and Parathunnus sibi; Hawaii. (Based on eight specimens from first host and 10 more from second host.) Body ovate, foliate, with two pairs of small eyespots, 11-23.5 x 8.5-21 mm, with a shallow but distinct median incision at posterior extremity. On each dorsolateral area there is a long zigzag row of 124-281, small, 2- to 5-cuspid teeth; immediately medial to this row is another longitudinal row of 16-32, larger, 1- to 2-cuspid teeth disposed at irregular intervals; each tooth has a broad base composed of granules; smaller teeth at times juxtaposed or obliquely tandem, extending between prohaptor and medioposterior incision; larger teeth less extensive; total number of small and large teeth 136-309 on one side. Frontal plate in form of transversely elongated trapezoid, 0.9-1.5 mm wide. Prohaptor saucershaped, 0.5-0.9 X 0.4-0.93 mm. Opisthohaptor 1.65-5.3 mm in diameter, with scalloped marginal membrane, situated at a variable distance from posterior median incision, divided by seven septa into a heptagonal central area and seven subtriangular areas; paired anchors at base of two posterior septa, only 20-40 ft long and pointed at each end. Mouth opening at level of eyespots; pharynx with postequatorial constriction, 0.95-2.0 X 0.96-1.9 mm, with numerous glandular papillae projecting into lumen of anterior portion. Esophagus short, surrounded by pharyngeal gland ducts; pharyngeal gland cells distributed immediately posterolateral to pharynx and adjacent portion of vitellarian area. Intestinal limb giving off numerous dendritic branches; the posterior-most inner branches from the two sides appear to unite anterior to the opisthohaptor; the principal limb, however, passes by the side of the opisthohaptor and terminates in

54

small branches reaching to the posterior end of the body; the paired anterior branches embracing the mouth and pharynx terminate close to each other between the two prohaptors. Testes 20-41 in number, mostly rounded, partly oval or irregular in outline, massed together in one layer in postovarian interintestinal area; a few of them may be seen on each side of the ovary, but none so far posteriorly as opisthohaptor, although Stunkard states that the testes extend posteriad almost to the level of the opisthohaptor in the sectioned specimen. It is to be noted that some of the testes are normal, whereas others are degenerated or atrophied and transformed into multinucleated, finely granular organs of varying size like Goto's gland in Benedenia. Vas deferens unusually narrow, passing on left side of ovary, turning back on itself in front of vitelline reservoir and running forward medial to vagina, finally entering cirrus pouch near its base. Cirrus pouch claviform, 0.351.1 X 0.12-0.3 mm, comparatively weakly muscular. Cirrus papillated, prostatic cells surrounding prostatic reservoir, enclosed in cirrus pouch at its base. Genital atrium reduced. Common genital pore on left of median line at level of esophagus.

DISCUSSION

Ovary multilobed, approximately rounded, 1.1-2.1 X 0.9-2.2 mm, median, nearly halfway between two haptors, giving rise to wide germiduct at its center. Shell gland cells strongly developed, forming two subsymmetrical groups anterior to ovary, connected with proximal end of ootype by long convergent ducts. Ootype fusiform, uterus proper opening beside male pore into genital atrium. Eggs quadrangular, 90 X 110 /»; a short filament arising from each comer. Vitellaria consisting of small follicles, extending throughout body except for its marginal area and the regions occupied by haptors, mouth, pharynx, esophagus, and beginning of intestinal limbs and gonads; collecting vitelline ducts running along intestinal branches on their ventral side; paired anterior collecting ducts with an arcuate transverse anastomosis ventral to anterior intestinal arc; a transverse commissure is seen in front of the opisthohaptor between two posterior collecting ducts; vitelline reservoir ovoid, 0.2-0.45 X 0.22-0.55 mm, situated immediately in front of ovary, receiving seminal duct from receptaculum seminis vaginae on the left and giving off its efferent duct on the right. I was unable to confirm Stunkard's statement that the oviduct receives the duct from the seminal receptacle. Vagina opening ventrally just outside of left intestinal limb a little posterolateral to genital pore; vaginal duct winding proximally; seminal receptacle elliptical, 0.080.25 X 0.09-0.15 mm; seminal duct narrow, straight, connecting proximal end of seminal receptacle and anterosinistral corner of vitelline reservoir. Stunkard (1962) assigned this species to Caballerocotyla Price, i960, but the type species of that genus is quite different from the present species not only in habitat, general shape, and armature of body but also in internal anatomy, especially in the testes being partly degenerate and occupying the anterior interintestinal field alone, and in the vas deferens and prostatic complex being very poorly developed. For these reasons

Capsalidae

55

I prefer to propose a new genus Nasicola with the present species as type. The generic name refers to the peculiar habitat—the nasal cavity of the host.

Nasicola n. gen. GENERIC DIAGNOSIS

TYPE SPECIES

Subfamily 28 HABITAT HOLOTYPE DESCRIPTION

Capsalidae, Capsalinae. Body oculate, ovate, foliate, with distinct median notch posteriorly. Along the dorsomarginal area between the prohaptor and the posterior notch there are long rows of teeth, of which the outer zigzag row consists of small, 2- to 5-cuspid teeth, whereas the inner row consists of larger, 1- to 2-cuspid teeth disposed at irregular intervals. Prohaptor saucer-shaped, one-fourth to one-fifth the diameter of opisthohaptor. Opisthohaptor sessile, with scalloped marginal membrane, well apart from posterior median notch of body, with its non-papillate ventral surface divided by seven septa into a heptagonal central loculus and seven subtriangular marginal loculi, provided with a pair of very small simple anchors. Pharynx constricted into two portions; intestinal limbs with dendritic branches, apparently united in front of opisthohaptor by transverse anastomosis. Testes not very numerous, occupying anterior para- and postovarian, interintestinal field; some of them conspicuously degenerated or atrophied unlike other normal ones. Vas deferens and prostatic gland complex very poorly developed, the latter enclosed in cirrus pouch at its base. Cirrus pouch claviform, cirrus papillated. Genital atrium reduced, opening posterosinistral to pharynx. Ovary multilobed, median, about halfway between anterior and posterior haptors. Shell gland cells well developed on each side in front of ovary. Eggs quadrangular, filamented. Vitellaria profusely developed throughout body except in marginal area and median field occupied by pharynx and gonads; vitelline reservoir submedian, preovarian. Vagina opening a little posterior to genital pore; receptaculum seminis vaginae present. Parasitic in nasal cavity of marine teleosts. N. klawei (Stunkard, 1962) n. comb., in Neothunnus macropterus and Parathunnus sibi; Mexican Pacific and Hawaii.

NITZSCHIINAE

Johnston, 1931

Pseudonitzschia uku Yamaguti, 1965

FIGURE 2 8

Gill of Aprion virescens (local name "uku"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 3. (Based on 16 whole mounts.) Body flattened subcylindrical, 2.15-3.7 X 0.5-1.1 mm. Opisthohaptor discoid, with thick muscular margin distinctly notched midlaterally and inconspicuously at posterolateral or posterior

56

DISCUSSION

Family Subfamily 29 HABITAT

margin; delicate marginal membrane present, but anchors and marginal hooklets entirely absent. Prohaptors glandular, saucer-shaped, 0.28-0.4 mm long. One pair of eyespots anterodorsal to pharynx. Pharynx 0.08-0.24 X 0.1-0.28 mm, without lateral constriction. Esophagus practically absent. Intestinal limbs with side branches, extending to near opisthohaptor without uniting together. Testes rounded, 20-30 in number (most commonly 2 5 - 2 8 ) , arranged in one layer, occupying anterior part of postovarian interintestinal field. Vas deferens convoluted anterior to vitelline reservoir, turning back on itself in cirrus pouch to lead into ejaculatory duct; latter duct muscular, joining narrow prostatic duct at base of cirrus. Cirrus conical, projecting into genital atrium, covered all over with very small recurved spines. From the base of the cirrus arises a claviform muscular gonotyl which is about 100 X 40 ft, in the type and directed obliquely backward. Cirrus pouch subcylindrical, curved, 0.22-0.4 x 0.08-0.15 m m > situated almost longitudinally behind pharynx, provided with circular and oblique muscle fibers. Prostatic reservoir ovoid, 75-140 X 60-140 n, posterior to cirrus pouch; prostatic duct a little swollen and enclosed in a prominent muscle bulb of oblique fibers at posterior end of cirrus pouch, then running straight forward within cirrus pouch and finally uniting with ejaculatory duct. Genital atrium cylindrical, enclosing cirrus pouch, receiving uterus at level of cirrus, opening ventrally beneath left prohaptor. Ovary subglobular, 0.12-0.24 x 0.08-0.21 mm, situated nearly in median line at posterior end of anterior third of body. Uterus opening into genital atrium dorsal to cirrus. Eggs one at a time, pentagonal, about 0.1 mm in diameter, with filament at one pole. Vagina lined with thick corrugated cuticle, opening dorsally near left margin of body at level of pharynx; vaginal duct with fusiform or tubular swelling distally; no receptaculum seminis vaginae. Vitellaria co-extensive with intestine; vitelline reservoir on left side of ovary, more or less curved toward ovary, 0.1-0.23 X 0.060.12 mm. This genus is characterized by the opisthohaptor being unarmed, although in general anatomy it resembles Nitzschia Baer, 1826. It is separated from all the known subfamilies of Capsalidae and represents a new subfamily on account of this unarmed opisthohaptor. For diagnoses of this genus and the subfamily Pseudonitzschiinae and further details, see Pacific Science i 9 ( i ) : 6 o - 6 i .

MICROBOTHRIIDAE ENOPLOCOTYLINAE

Price, 1936

Tagliani, 1 9 1 2

Enoplocotyle hawaiiensis n. sp.

FIGURE

29

Gill and skin of Amanses partialis (type host, Monacanthidae), Balistes bursa (Balistidae), Centropyge potteri and Chaetodon lunula (Chaeto-

Microbothriidae

HOLOTYPE DESCRIPTION

DISCUSSION

57

dontidae), Holocentrus scythrops (Holocentridae), Priacanthus boops (Priacanthidae), Dendrochirus brachypterns (Scorpaenidae), and Caesioperca thompsoni (Serranidae); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 104. (Based on four whole mounts from type host.) Body elongate, tapering posteriorly, 0.4-0.6 mm long, 0.09-0.22 mm wide at junction of anterior with middle third of body. Opisthohaptor small, discdid, 32-65 ¡x in diameter, provided ventrally with a circle of 14, apically strongly curved, marginal hooklets 1 1 - 1 4 l° n g and a central pair of similar, slightly smaller hooklets. Prohaptor represented by truncate head, along the margin of which are two pairs of head organs; head glands extending along each side of body in pharyngeal zone. Mouth opening ventrally, followed by distinct prepharynx; pharynx globular, 20-32 X 23-33 Esophagus wide and short; ceca narrow, simple, terminating separately in anterior half of posterior third of body. Testis subglobular or rounded triangular, 28-46 X 35-70 ¡x, postequatorial; vas deferens opening into base of cirrus without forming either seminal vesicle or pars prostatica; prostatic cells, however, are strongly developed on each side posterior to head gland cells; prostatic reservoir ovoid, 30-58 X 20-30 intercalated between uterus and right cecum, emptying into base of cirrus. Cirrus pouch reduced to a sheath enclosing cirrus. Cirrus tubular, curved, about 70-100 ¡j. long by 14 ¡i wide at base, well sclerotized, articulated at its tip with another sclerotized piece 32-37 /i long. There is a saddle-shaped accessory piece about 30 ju. long lineally. Male pore opening on left margin of body at level of pharynx. Ovary globular, 35-54 X 35-70 ¡x, immediately pretesticular. Uterus surrounded proximally by compact mass of shell gland cells studded with dark staining granules. Uterine pore on left margin of body a little posterior to male pore. Uterine eggs one at a time, 67-93 x 3 2 _ 4° with short posterior filament terminating in a disc. Vitelline follicles unusually large, extending along each side of body, 12-13 on each side from level of uterus to near cecal ends, with two longitudinal rows of six follicles each in posttesticular intercecal field; transverse vitelline duct immediately preovarian; vitelline reservoir subglobular, overlapping ovary on its anteroventral side. Vagina opening ventral to left cecum at level of shell gland; receptaculum seminis vaginae pyriform, just anterosinistral to ovary, connected with germiduct by a short seminal duct arising from its base. This species differs from Enoplocotyle minima Tagliani, 1909 in body shape, structure of cirrus, and in its less numerous lateral vitelline follicles, etc. In Tagliani's figure of E. minima, reproduced by Bychowsky (1957), there are numerous, large, irregularly shaped cells outside the lateral vitelline follicles and between the cecal ends and the opisthohaptor, but no such cells have been observed in the present species. It is to be noted that this species occurs on fishes of seven different families, though only one specimen was found at a time from the gill washing, except in the type host and in Dendrochirus bachypterus, from which more specimens were collected from the washings of the gills and skin.

58

Family Subfamily

30 HABITAT

HOLOTYPE DESCRIPTION

MONOCOTYLIDAE Taschenberg, 1879 MONOCOTYLINAE Gamble, 1896

Diploheterocotyla dasyatis Yamaguti, 1 9 6 5

FIGURE 3 0

Gill of Dasyatis sp. (D. hawaiiensis?); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 4. (Based on seven whole mounts.) Body elliptical in outline, 0.9-1.2 X 0.3-0.53 mm, covered with smooth cuticle. Opisthohaptor circular, 2.123.15 mm in diameter, divided into a round central loculus 65-115 ¡x across and eight muscular marginal loculi, provided with a marginal membrane up to 30-35 ix wide and a pair of anchors measuring 27-33 A* lineally from tip of ventral root to height of curve of blade and 35-53 /x lineally from tip of dorsal root to height of curve of blade; dorsal root inserted deeply into the septum between posterior submedian and posterolateral loculi. Marginal hooklets hardly recognizable at each interlocular marginal notch. Oral sucker subterminal, 65-100 X 100-155 /*> surmounted on its anterodorsal border by a transversely elongated pillow-like lobe. Prepharynx distinct. Pharynx globular, 62-85 ¡x in diameter. Ceca wide, with short inner and longer outer branches, terminating dorsal to opisthohaptor where the most medial branches appear to be united together. Testes oval, about 100 ¡x long, almost symmetrical, one on each side of median ovarian curvature. Vas deferens turning round bulbus ejaculatorius and penetrating it at its posterior end, forming two dilatations, one immediately in front of the bulbus and the other immediately behind the bulbus, both serving as seminoprostatic reservoirs because they contain spermatozoa and prostatic granules secreted from the neighboring prostate cells. Bulbus ejaculatorius 75-110 X 57-80 ¡x, containing abundant granules in wide space between its wall of circular muscles and the ejaculatory duct. Copulatory organ consisting of a well sclerotized, tubular cirrus proper which is 30-45 ¡x long, more or less flared at each end, and provided sideways with a sclerotized fold and of a bundle of about 10, slightly curved, slender, accessory spines. To the base of the cirrus are attached special whirling muscle bundles merging into surrounding body parenchyma, probably associated with movements of the cirrus. Ovary 75-150X150-250 ¡x, just postequatorial; its greater proximal portion V-shaped, with its proximal end more or less swollen and its right arm embracing right intestinal limb. Uterus proper funnel-shaped, with distinct epithelial lining, opening midventrally by a large rounded aperture behind male pore. Eggs mitral, 75-83 ¡x long by 75-83 ¡x wide in life, 95-100 X 80-95 A1 i n mounted condition, with prominent posterior lateral ends, from one of which arises a fine filament. Vagina strongly sclerotized basally, opening ventrally medial to left intestinal limb. Seminal receptacle rounded, 40-60 p in diameter, enclosed in proximal portion

Monocotylidae

DISCUSSION

31 SYN.

HABITAT DESCRIPTION

59

of vagina. Vitellaria co-extensive with intestine; transverse vitelline duct equatorial. This monocotylid genus differs from any other members of the subfamily Monocotylinae by possessing two testes instead of one, although it resembles Heterocotyle minima (MacCallum, 1916) Price, 1938 in general anatomy. The generic name refers to this feature. For further details, see Pacific Science 1 9 ( 1 ) : 6 I - 6 2 .

Alloheterocotyla aetobatis (Hargis, 1955) n. comb. Heterocotyle aetobatis Hargis, 1955 Heterocotyle floridana of Pearse, 1 9 4 9

FIGURE 3 1

Gills of Aetobatis narinari; Hawaii. (Based on 1 4 whole mounts.) Body elongate, 1 . 1 - 1 . 5 M M * N Length, 0 . 1 8 - 0 . 4 4 mm wide in midregion. No eyespots. Opisthohaptor circular, a little wider than long, 0 . 2 4 - 0 . 3 2 X 0 . 2 5 - 0 . 3 9 mm, divided by ten muscular septa into ten radial loculi surrounding polygonal central loculus, fringed with delicate membrane, at apex of each posterolateral septum armed with a hook with a long guard and measuring 4 4 - 5 8 ¡x long from base to height of curve of sickle-shaped blade; on the dorsal surface of the two posterior-most loculi there are six, conical, pointed, muscular papillae arranged in inverted V-shaped pattern with the point directed forward; the muscular margin of the opisthohaptor is usually notched at the apex of each septum, and the marginal membrane is not always provided with full number of larval hooklets, some of which are often missing. The peduncle glands of Hargis can be distinguished from the vitelline gland only by their rather irregular shape and their distribution in the posterior part of the peduncle; the clear space observed by Hargis as opening posteriorly is seen at the posterior end of the peduncle in extended specimens; whether or not it opens posteriorly could not be determined. Mouth subterminal, funnel-shaped; oral sucker weakly muscular, 0 . 1 4 - 0 . 2 1 mm in transverse diameter, produced anteriorly and surmounted by a broad hood-like flap containing ducts from the head glands which lie in three (a median and a pair of submedian) groups in the dorsal wall of the buccal funnel. Pharynx globular, not bipartite, strongly muscular, 0 . 0 8 - 0 . 1 3 X 0 . 0 8 - 0 . 1 5 mm; esophagus practically absent; ceca simple, inflated posteriorly and united posteriorly to form a short median cecum.

Testis oval, 6 0 - 1 6 0 X 6 0 - 1 3 0 ¡i, just postequatorial, intercecal, giving rise to vas deferens at its anetrosinistral corner. Vesicula seminalis retortshaped, 0 . 0 7 - 0 . 1 2 X 0 . 0 4 - 0 . 0 8 mm, situated immediately posterodextral to pharynx, with its long axis oblique to median line, giving off ejaculatory duct at its posterior end. This duct is comparatively short and enters the muscular cirrus bulb from behind or right side. Copulatory organ consisting of a well sclerotized, coiled, spicular cirrus with its recurved tip (not

6o

DISCUSSION

spatulate as described by Hargis) directed backward or forward, and a spherical basal bulb enclosed in the cirrus coil, measuring 50-100 /* long lineally as a whole. Common genital pore midventral, a little behind pharynx. Ovary bending back on itself twice, embracing right cecum as depicted by Hargis, 0.06-0.16 X 0.06-0.13 mm, contiguous with testis anterodextral to it. The germiduct arising from the left end of the ovary unites with the twisted vaginal duct as well as with the vitelline duct, from which it then turns forward and is surrounded by shell gland before leading into the large, saccular, thin-walled "ootype-uterus" of Hargis, 0.07-0.12 mm long. This latter portion is thin-walled, with vesiculate lining, and may occasionally be a simple tube; the comparatively wide duct ( = uterus proper) connecting this ootype-uterus with the common genital pore is variable in length, sometimes short and straight, sometimes long and curved. Eggs one at a time, round, 84 in diameter, with a small hookshaped filament about 14 p. long lineally at its posterior end. Vitellaria surrounding ceca, confluent posteriorly, more extensive than described and illustrated by Hargis. Vagina funnel-shaped or subcylindrical, provided with thick wall of circular muscle fibers, opening ventrally in left submedian line at about level of cirrus bulb; vaginal duct sigmoid or twisted. This species differs from any known species of Heterocotyle in possessing ten radial septa instead of eight and conical muscular papillae on the dorsal side of the two posterior-most loculi. These characters are sufficient to justify the erection of a new genus, for which Alloheterocotyla is proposed, with the following diagnosis.

Alloheterocotyla n. gen. GENERIC DIAGNOSIS

Monocotylidae, Monocotylinae. Opisthohaptor divided by septa into ten marginal loculi and a central loculus, with one pair of anchors and a number of marginal hooklets, and conical muscular papillae on dorsal side of two posterior-most loculi. No special structures on septal and marginal ridges of opisthohaptor. Eye absent. Oral sucker weakly developed, surmounted by fleshy lobe. Pharynx strongly muscular; esophagus absent; ceca confluent posteriorly. Testes single, postequatorial. Seminal vesicle conspicuous. Copulatory organ consisting of basal bulb and a spicular cirrus. Common genital pore midventral, postpharyngeal. Ovary embracing intestinal limb, pretesticular, submedian. Ootype usually large, bulbous. Eggs one at a time, spherical, with hook-shaped filament at posterior end. Vagina well developed, with submedian opening; no seminal receptacle. Vitellaria co-extensive with intestine. Gill parasites of elasmobranchs.

TYPE SPECIES

A. aetobatis (Hargis, 1955) n. comb., syn. Heterocotyle aetobatis Hargis, 1955, on Aetobatis narinari; Atlantic and Pacific.

Dactylogyridae

Superfamily

DACTYLOGYROIDEA Yamaguti, 1963

Family

DACTYLOGYRIDAE Bychowsky, 1933

Subfamily

32 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

ANOPLOCEPHALINAE

Bychowsky,

Ancyrocephahis omatus n. sp.

61

1937

FIGURE 3 2

Gills of Arothron hispidus (local name "keke"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 0 5 . (Based on 2 1 whole mounts.) Body flattened subcylindrical, 0 . 9 5 - 1 . 5 mm in length, with maximum width of 0 . 1 2 - 0 . 3 4 mm in greater middle portion. Opisthohaptor 1 2 5 - 2 0 0 p wide at level of lateral prominences; dorsal anchor 4 7 - 6 0 p long from tip of prominent dorsal root to height of curve of blade; dorsal bar somewhat arcuate, 6 2 - 7 5 p long; ventral anchor 5 0 63 p. long from tip of prominent ventral root to height of curve of blade; ventral bar with prominent paired submedian swellings and posterolaterally directed arms, 5 2 - 7 0 p long; marginal hooklets 1 0 - 1 3 P Head trapezoidal, 0 . 1 3 - 0 . 2 mm wide, with head organs as usual. Two pairs of eyespots anterior to mouth. A muscular prepharynx present, 5 2 - 1 1 0 p in diameter; pharynx 5 0 - 7 7 X 57—95 p. Esophagus very short; ceca terminating separately at about middle of posterior third of body. Testis elliptical, 5 0 - 1 0 0 X 2 5 - 5 0 p, at posterior end of middle third of body. Vas deferens running straight forward, medial to left cecum, bending back on itself near genital pore to lead into seminal vesicle, which is longitudinally elongated, 10-15 p wide, and lies to left of prostatic reservoir. Prostatic cells divided into a small anterior and a very large posterior group extending between base of cirrus and transverse vitelline duct. Prostatic reservoir fusiform or claviform, 3 0 - 5 0 X 7 - 1 3 p, situated longitudinally between cirrus and seminal vesicle. Cirrus 6 0 - 9 5 p long, slightly swollen proximally, provided with a spiral fold along its tapering sigmoid distal portion and with a somewhat spiral muscle bundle extending from base to its tip. Genital pore just behind intestinal bifurcation. Ovary oval or elongate in extended specimens, 1 0 5 - 1 7 5 X 4 0 - 1 0 0 p, just postequatorial. Seminal receptacle 2 5 - 5 0 X 1 7 - 4 5 p, just behind transverse vitelline duct, giving on each side a short transverse or oblique canalis receptaculi seminis which, however, could not be traced to its distal end. Vagina tubular, narrow, opening on right margin of body a little anterior to transverse vitelline duct. Eggs 80 p in diameter in collapsed condition; with winding filament, the posterior end of which has a cap-like expansion 25 p in diameter. Vitellaria co-extensive with intestine; transverse vitelline duct just pre-equatorial. This species is characterized by the cirrus being ornamented distally with a spiral fold; hence the specific name. The presence of a muscular prepharynx and of symmetrical canalis receptaculi seminis in the present species is worth noting.

62

33 HABITAT HOLOTYPE DESCRIPTION

Aticyrocephaltis parupenei n. sp.

FIGURE 3 3

Gills of Parupeneus chryserydros (type host), P.multifasciatus and P. pleurostigma; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 106. (Based on 40 whole mounts.) Body flattened subcylindrical, 0.66-1.0 X 0.13-0.22 mm, widest a little behind intestinal bifurcation. Opisthohaptor 50-125 ju wide, shallowly constricted from body proper; dorsal anchor 48-65 ¡X from tip of longer root to height of curve of blade; dorsal bar thickened at greater middle portion, with anterolaterally directed end articulating with longer dorsal root of dorsal anchor, 35-58 ¡i long; ventral anchor 47-55 long, broadened at base, with stout ventral root; ventral bar 30-70 ix long, articulating with longer ventral root of ventral anchor. Of the marginal hooklets only three pairs were seen at the lateral prominences in the type. Head with two pairs of lobes, 75-125 f. wide at level of posterior lobes; head organs conspicuous. Two pairs of eyespots dorsal to pharynx. Pharynx globular, 30-50 ¡i in diameter. Esophagus very short. Ceca terminating separately a little behind testis. Testis elliptical, postequatorial, 35-112 x 20-50 ¡x. Vas deferens passing on left side of ovary and medial to left cecum, bending back on itself anteriorly to form seminal vesicle. Cirrus approximately cylindrical, curved, 80-105 f- l°ng> with bell-shaped base. To the convex side of the cirrus is attached an undulating fold which makes the outline of the cirrus very irregular. Prostatic cells well developed immediately behind intestinal bifurcation. Prostatic reservoir claviform, situated longitudinally between cirrus and seminal vesicle. Genital pore a little postbifurcal. Ovary oval to fusiform, 35-90 X 20-50 ¡x, equatorial. Eggs oval, 77105 X 50-70 ¡i, with a short filament (up to 65 long), whose tip may or may not be enlarged. Vitellaria co-extensive with intestine. Vagina subcylindrical to fusiform, muscular, 30-50 X 15-25 when not evaginated, 20-38 fi in diameter when evaginated, opening on dextroventral margin at level of posterior end of base of cirrus in form of a funnel. Vaginal duct running obliquely backward from posterior end of vagina. Seminal receptacle small, oval.

DISCUSSION

34 HABITAT HOLOTYPE DESCRIPTION

This species is characterized by the structure of the cirrus.

Aticyrocephaltis pauu n. sp.

FIGURE 3 4

Gills of Myripristis chryseres (type host, local name "pauu") and Ostichthys japonicus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 107. (Based on 13 whole mounts.) Body 0.5-0.86 mm long, slender when extended as in the type, usually with maximum width of 70-130 ¡x in region of copulatory organ or testis, somewhat constricted in region of vagina.

Dactylogyiidae

63

Opisthohaptor 65-95 wide, with two pairs of anchors of nearly equal length, two dissimilar bars and 14 marginal hooklets up to 14 ¡i long; dorsal anchor 58-68 ¡x long from tip of dorsal root to height of curve of blade; ventral root of this anchor reduced to a flat thickening; dorsal bar arcuate, 34-54 long, with a pair of small, comma-shaped, submedian excrescences on anterior face; ventral anchor 58-65 ¡x long from tip of very prominent ventral root to height of curve of blade, with dorsal root markedly reduced; ventral bar straight, 23-37 ¡i long. Head rather truncate, though projecting at anterior end of each head organ. Usually only one pair of compact eyespots, sometimes none. Pharynx 18-26 X 16-26 ¡x. A short esophagus visible in extended specimens alone. Ceca terminating parallel to each other in anterior half of posterior third of body. Testis bent back on itself; 46-105 X 23-70 fx, situated at posterior end of middle third of body. Vas deferens running straight forward medial to left cecum, forming a fusiform or claviform seminal vesicle 11-23 P P os " terior to cirrus, turning back on itself further anteriorly beside cirrus to form another seminal vesicle. Ejaculatory duct entering alongside efferent duct of prostatic reservoir into muscular cylinder which lies longitudinally beside the basal portion of the cirrus, at the recurrent posterior end of which originates the cirrus. This muscle cylinder, characteristic of the present species, is 30-47 ¡x long by 1 1 - 1 6 n wide, is surrounded by a thick coat of inner longitudinal and outer circular muscle fibers, and has a narrow, heavily cuticularized lumen continuous with the basal lumen of the cirrus. It seems that this organ represents a modification sui generis of the conventional muscular sheath of the cirrus. Cirrus tubular, slender, 831 1 7 / 1 long, provided throughout its length with a spiral cuticular fold, terminating in a recurved point at intestinal bifurcation. Prostatic reservoir longitudinally elongated, 23-42 X 6.5-9 ¡x; prostatic cells divided into two (an anterior and a posterior) groups. A tubular prostatic reservoir, surrounded by circular muscle fibers and filled with fine granules is seen opening into the above mentioned muscle cylinder.

DISCUSSION

Ovary small, oval to elongate pyriform, 23-40 X 13-23 /x, pretesticular, to right of median line. Vagina cylindrical or elongate claviform, muscular, 70-117 X 13-23 [i, opening on right margin of body nearly halfway between its own base and that of cirrus. Vaginal duct arising sideways very close to posterior end of vagina in form of a swollen diverticle 5-7 ¡x wide, which is connected to the germiduct by a short very narrow duct. Eggs shrunken in uterus, oval, about 72 ¡x long by 58-61 ¡x wide; posterior polar filament 81-93 ¡x long, thickened posteriorly into a slender club, dumbbell, or button. Vitellaria co-extensive with intestine. This species is characterized by the cirrus being provided with a spiral cuticular fold extending throughout its length and continuous at the base with a strongly muscular cylinder, the function of which is unknown. The shape of the testis as well as the structure of the vagina and vaginal duct constitute another differential character.

64

KEY TO SPECIES OF

Ancyrocephalus FROM HAWAIIAN FISHES

35 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

Testis folded back on itself; terminally curved muscular cylinder attached to proximal end of cirrus; vaginal duct arising subterminally from vagina: A. patitt Testis not folded back on itself; no muscular cylinder attached to proximal end of cirrus; vaginal duct arising terminally from vagina: 2 Cirrus sigmoid, slender, with spiral fold; paired canalis receptaculi seminis present: A. ornatus Cirrus cylindrical, curved, with irregular (not spiral) fold; canalis receptaculi seminis absent: A. parupenei Haliotrema aeanthuri n. sp.

FIGURE 3 5

Gills of Acanthurus sandvicensis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 108. (Based on 26 whole mounts.) Body elongate, subcylindrical, 0.35-0.7 mm in length, with maximum width of 46-128 p at level of testis. Opisthohaptor 70-140 ¡x wide at level of lateral projections; dorsal anchor 56-75 ¡x long lineally from tip of long dorsal root to height of curve of blade; dorsal and ventral bars 50-63 ¡x long, similar in shape, each with paired submedian swellings and posterolaterally directed arms; ventral anchor 5063 ¡i long from tip of ventral root to height of curve of blade, with short bifid root. Muscle fibers between anchors and bars well developed. Cement glands well developed immediately behind posterior end of vitellaria. Three pairs of marginal hooklets 13-15 ¡x long along sloping anterolateral margins of opisthohaptor. Head trapezoidal, 38-77 ¡1 wide at base, with well developed head organs along lateral borders. Pharynx 17-33 x 15-30 n, with dissociated eye pigment dorsolaterally. Esophagus very short; ceca united posterior to testis. Testis oval to elliptical, 45-120 X 25-93 P> situated at junction of middle with posterior third of body. Vas deferens looping around left cecum at level of transverse vitelline duct, forming a longitudinal seminal vesicle between prostatic reservoir and left cecum. Copulatory organ 32-48 ¡x long lineally, consisting of a bell-shaped base and a short cylindrical shaft, from which arise a spicular cirrus proper and a similar, solid, shorter prong projecting out of genital pore. Prostatic cells massed together between cirrus and intestinal bifurcation. Prostatic reservoir inverted claviform, situated longitudinally between copulatory organ and seminal vesicle, receiving ascending duct from posterior group of prostatic cells. Genital pore median, shortly postbifurcal. Ovary longitudinally elongated, 25-70 X 10-54 /*> m o r e o r less overlapping testis posteriorly. No eggs observed. Vagina pyriform, muscular, 2028 X 15-23 ¡x, opening on right margin of body immediately in front of transverse vitelline duct; vaginal duct narrow, arising from anterior ventral surface of vagina toward middle. Seminal receptacle small, elongate. Vitellaria co-extensive with intestine. This species is characterized by the structure of the copulatory organ and

Dactylogyridae

65

vagina. In these respects it bears a certain resemblance to Haliotrema zancli n. sp., but it differs from the latter in the vaginal duct arising far from the base of the vagina. In H. zancli the vaginal duct originates at the base of the vagina. Furthermore, in the present species there are two groups of prostatic cells. In synonymizing Parahaliotrema Mizelle et Price, 1964 with Haliotrema Johnston et Tiegs, 1922, I would like to point out that in the latter genus the intestinal crura are actually confluent posteriorly (I examined the original type specimen of Johnston and Tiegs) and that the presence of eyespots is by no means a generic character in Ancyrocephalinae. The difference in the position of the vagina (dextral vs. dextroventral) suggested by Mizelle and Price as a third differentiating character is, needless to say, of no generic importance.

36 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

Haliotrema amanses n. sp.

FIGURE 3 6

Gills of Amanses pardalis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 109. (Based on eight whole mounts.) Body small, elongate, 0.35-0.6 mm long, up to 6 5 - 1 4 0 P. wide at posterior third of body, may be more or less constricted in region of vagina. Eyespots dissociated. Opisthohaptor transversely elongated rhombiform, 80-120 /» wide at level of lateral projections; marginal hooklets 9 - 1 0 ¡I long; dorsal anchor 32-49 ¡J. long from anterior end of dorsal root to height of curve of blade, with its base enlarged to a triangular fenestrated plate; dorsal bar slightly arcuate like ventral bar, 4 6 - 5 8 n long; ventral anchor 3 7 - 5 4 /J. from tip of prominent ventral root to height of curve of blade; ventral bar 4 6 - 5 8 /t long, with slight submedian bends. Head trapezoidal, with three pairs of head organs. Pharynx 16-39 x 35 esophagus short; ceca united posteriorly. Testis elliptical, 46-81 X 18-30 ¡L, situated medianly at junction of middle with posterior third of body. Vas deferens looping around left cecum and then around prostatic reservoir, forming a rather slender seminal vesicle. Cirrus 54-60 ¡x long lineally, consisting of a broad bell-shaped base 9-14 (i wide, a narrow, undulating, flanged, tubular cirrus arising from apex of bell-shaped base, and a short, curved, slender, fine, accessory spine associated with base of cirrus proper. Genital pore midventral, 93 ¡J. posterior to pharynx in the type. Prostatic reservoir saccular, 37 X 20 /x in the type, slightly anterior to base of cirrus. Ovary elliptical, 35-46 X 1 4 - 2 8 immediately pretesticular. Vagina tubular, straight, oblique, opening ventrally near right margin of body at about level of base of cirrus. Seminal receptacle small, elongated longitudinally. Vitellaria co-extensive with intestine, almost confluent between ovary and testis. This species is characterized by the structure of the copulatory organ and vagina.

66

37 HABITAT HOLOTYPE DESCRIPTION

Haliotrema

angulare n. sp.

FIGURE 37

Gills of Acanthurus nigroris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. n o . (Based on 16 whole mounts.) Body slender, cylindrical, 0.44-0.6 m m in length, up to 50-90 ¡x wide at ovariotesticular level. Opisthohaptor 6 5 110 ¡x wide, well marked off from body proper, with two pairs of fenestrated anchors, two dissimilar bars, and few marginal hooklets; dorsal anchor 4 5 - 6 0 p lineally from tip of dorsal root to height of curve of blade; dorsal bar with shallow sinus at middle of posterior margin, 30-45 /t long; ventral anchor 4 5 - 5 0 ¡x long from tip of ventral root to height of curve of blade; ventral bar angularly bent submedianly, 30-40 ¡x long. At the base of the opisthohaptor is an arcuate transverse muscle band sending off fine fibers to the base of each anchor. Head trapezoidal, 35-55 /x wide, with head organs along sloping lateral margin. N o eyespots. Pharynx 17-25 X 17-23 fi. Ceca united posterior to testis. Testis elliptical, 60-100 X 20-50 ft, at junction of middle with posterior third of body. Vas deferens looping around left cecum, turning backward just in front of cirrus to form fusiform seminal vesicle. Cirrus hook-shaped, with a short slender spine near its enlarged proximal end which is set on a wide annular base. Prostatic reservoir claviform, situated longitudinally alongside seminal vesicle. Genital pore a little to left of median line a short distance behind intestinal bifurcation. Ovary elongate, 35-100 X 1 7 - 3 0 ¡x, overlapping testis posteriorly, just postequatorial. N o mature eggs observed. Vagina fusiform or retortshaped, 30-48 X 10-15 I1' well developed longitudinal muscles, situated obliquely on the right, with its submarginal opening at level of base of cirrus. Vaginal duct arising subterminally from medial margin of vagina. Vitellaria extending along intestine further backward than cecal union. Seminal receptacle elongate, overlapping ovary. Egg oval, with short simple polar filament.

DISCUSSION

38 HABITAT HOLOTYPE DESCRIPTION

This species was found associated with Haliotrema flexicirrus n. sp., b u t it can be distinguished from the latter by the cirrus being shorter and never bent back on itself near the base and by the vagina being provided with well developed longitudinal muscle fibers. T h e specific name refers to the angular shape of the cirrus.

Haliotrema

angulocimis

n. sp.

FIGURE 38

Gills of a Monotaxis sp. (Monotaxis grandoculis?); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 111. (Based on 10 whole mounts.) Body flattened cylindrical, 0.56-1.0 m m in length, with maximum width of 8 5 - 1 2 0 ¡x. Opisthohaptor not markedly constricted off from body proper, 1 2 8 - 1 7 0 ¡x wide at level of lateral projections; dorsal anchor 51-58 ¡x long from tip of prominent dorsal root to

Dactylogyridae

DISCUSSION

39 HABITAT HOLOTYPE DESCRIPTION

67

height of curve of blade; dorsal bar bifid laterally, 4 6 - 6 5 ¡x long; ventral anchor 5 0 - 6 3 ¡x long from tip of ventral root to height of curve of blade; ventral bar rather slender, slightly arcuate, 46-51 ¡x long; marginal hooklets up to 1 4 n long. Head trapezoidal, 6 0 - 1 0 0 ¡x wide, with two pairs of large head organs. Two pairs of eyespots present. Pharynx barrel-shaped, 3 7 - 4 7 X 2 1 - 2 8 ¡x; esophagus very short; ceca confluent posteriorly. Testis elliptical, 5 8 - 1 1 1 X 1 6 - 2 8 in posterior half of middle third of body. Vas deferens turning round left cecum and forming an inverted U-tum before opening into cirrus. Cirrus tubular, 3 4 - 3 7 /x long lineally from base to height of curve, right-angled near its claw-like point; main shaft and swollen base completely enclosed in sheath of longitudinal muscle fibers. Prostatic reservoir claviform, 9 ft wide, situated longitudinally, with its base directed toward postbifurcal prostatic cells. Genital pore a short distance posterior to intestinal bifurcation. Ovary subglobular to oval, 3 4 - 4 2 X 1 6 - 3 0 ¡x, immediately pretesticular, to right of median line. Only one egg (crumpled), 83 X 58 ¡x, was observed in the uterus of one specimen. Vagina subcylindrical, weakly muscular, 4 0 - 5 0 X 1 8 - 2 3 situated a little obliquely at anterior part of middle third of body with its basal lumen filled with sperm; vaginal duct very narrow, arising subterminally from base of vagina. Seminal receptacle oval. Vitellaria co-extensive with intestine. This species is characterized by the cirrus being curved like an angler's hook or a cloak-room peg and by the vagina forming a sperm chamber at the base.

Haliotrema annulocirrtis n. sp.

FIGURE 3 9

Gills of Chaetodon auriga (type host) and C. lunula; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 1 2 . (Based on 2 3 whole mounts.) Body small, elongate, 0 . 3 3 - 0 . 6 6 mm in length, with maximum width of 0 . 0 7 - 0 . 1 7 mm at level of testis, whence it tapers gradually toward the head end. Opisthohaptor slightly marked off from body proper, 7 0 - 1 1 7 ¡x in maximum width at level of lateral projections, each of which bears four marginal hooklets close together; dorsal anchor with broad truncate base, 23-33 ¡x long lineally from anterior end of base to height of curve of blade; dorsal bar thickened toward middle, n 2 7 - 3 5 M l° g; ventral anchor 3 0 - 3 5 ¡x long from tip of ventral root to height of curve of blade; dorsal root strongly reduced; ventral bar with a slight thickening at middle, 3 0 - 4 0 ¡x long; marginal hooklets about 1 0 ¡x long. Head end blunt-pointed, 3 2 - 5 4 fx wide. Two pairs of eyespots anterior to mouth. Pharynx nearly spherical; esophagus very short, with postpharyngeal glands on each side. Ceca simple, united posteriorly. Testis elliptical, 5 1 - 1 4 0 X 3 0 - 9 0 /*, at junction of middle with posterior third of body. Vas deferens narrow, turning round left cecum, forming seminal vesicle 9-16 ¡x wide a little behind copulatory organ. Copulatory

68

DISCUSSION

40 HABITAT HOLOTYPE DESCRIPTION

organ consisting of a long, spicular, tubular cirrus, spirally coiled back on itself proximally three and a half times, passing distally through tubular sheath which is continued basally into the cuticular flange of coiled portion of cirrus. Prostatic reservoir small, retort-shaped, 17-25 X 7-16 p, overlapping seminal vesicle behind cirrus. Genital pore immediately postbifurcal. Ovary rounded, 3 4 - 8 5 X 2 8 - 9 5 m m > immediately postequatorial. No eggs observed. Vagina funnel-shaped, with finely serrated margin 10-25 in diameter; vaginal duct strongly winding before joining seminal receptacle; later subcylindrical, saccular, or curved, 18-50 X 9-50 ¡x, situated posterior to transverse vitelline duct. Fertilization chamber enormously inflated. Vitellaria co-extensive with intestine, markedly reduced between level of cirrus and level of seminal receptacle. This species is characterized by the long, coiled, s'picular cirrus, to which the specific name refers, and by the peculiar structure of the vagina and vaginal duct.

Haliotrema bifurcocirrus n. sp.

FIGURE 40

Gills of Parupeneus porphyreus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 113. (Based on six whole mounts.) Body flattened subcylindrical, 0 . 6 - 0 . 7 6 X 0 . 1 2 - 0 . 1 6 mm. Opisthohaptor slightly constricted off from body proper, 0 . 1 2 - 0 . 1 4 mm wide; dorsal anchor 6 0 - 6 8 ¡x. long from tip of longer dorsal root to height of curve of blade; dorsal bar straight, 55-70 /x long, with a pair of prominent, anterolaterally directed, subterminal projections so as to assume a bifid appearance; ventral anchor similar in shape to dorsal anchor except for its dorsal root, the pointed end of which is curved at right angles, 5 5 - 6 8 ¡x long from tip of ventral root to height of curve of blade; ventral bar rounded at both ends, 5 0 - 7 0 p long; marginal hooklets about 10 n long. Head prominent at apex in the type, with well developed head organs. Pharynx 2 7 - 3 3 x 3°~33 >*•> c e c a united posterior to testis. Testis oval, 7 5 - 9 5 X 4 5 - 7 0 at junction of middle with posterior third of body. Vas deferens looping around left cecum, turning back on itself to form seminal vesicle. Cirrus tubular, coiled back on itself once and tapering to a slender spicule, somewhat bulbous, at its proximal end surrounded by circular muscle fibers and set on bell-shaped base which is 2 0 - 2 8 ¡j. wide. A solid spicule arises from the first turning point of the cirrus and is directed straight forward, so that the cirrus looks bifurcate. Prostatic reservoir fusiform, 4 5 - 5 5 X 1 0 - 1 5 ¡i, slightly curved alongside seminal vesicle on its medial side, receiving ascending prostatic duct draining well developed prostatic cells lying mostly posterior to cirrus. Some prostatic cells are seen in the extracecal fields in the cirro-vaginal zone. Genital pore immediately postbifurcal.

Dactylogyridae

DISCUSSION

41 HABITAT HOLOTYPE DESCRIPTION

69

Ovary oval, 50-75 X 35-50 ¡x, just postequatorial in the type, with strongly developed shell gland cells in front. Eggs rounded, about 55 X 50 fi, with short appendage at each end. Vagina funnel-shaped, nonmuscular, opening on right margin of body; its tubular portion winding and leading into narrower vaginal duct which joins the seminal receptacle at the point where the shell gland cells are converged. Vitellaria co-extensive with intestine and reaching to near base of opisthohaptor. This species is characterized by the cirrus being provided with a long solid accessory spicule at the point where it starts its distal looping. The specific name refers to this bifurcating appearance of the cirrus.

Haliotrema bisegmentatum n. sp.

FIGURE 4 1

Gills of Pomacentrus jenkinsi; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 1 4 . (Based on 18 whole mounts.) Body flattened subcylindrical, 0.37-0.6 X 0.06-0.13 mm. Opisthohaptor well constricted off from body proper, 90180 ¡x wide at level of lateral projections; dorsal anchor 4 8 - 7 4 ¡x long from tip of dorsal root to height of curve of blade; its ventral root almost completely reduced; dorsal bar 51-86 ¡x long, coathanger-shaped, with attenuated ends, but much thicker though less strongly sclerotized than ventral bar; ventral anchor 51-77 /x long from tip of ventral root to height of curve of blade, its dorsal root forming a broadly flattened protuberance; ventral bar slender, coathanger-shaped, 56-88 jx long; marginal hooklets about 9 ¡x long. Head three-lobed, 4 6 - 7 2 jx wide; frontal lobe rounded, with a pair of conspicuous head organs and a smaller head organ intercalated on each side between apical and lateral lobes. No compact eyespots, though some pigment granules are scattered anterodorsal to pharynx. Pharynx weakly muscular, 16-28 X 14-23 p.. Ceca united behind testis. Testis rounded, 46-70 X 23-46 fx, situated at junction of middle with posterior third of body. Vas deferens looping around left cecum, turning back on itself at level of tip of cirrus to pass into inverted claviform seminal vesicle; latter tapered and emptying into base of cirrus. Prostatic reservoir inverted claviform, up to 46 X 14 ¡x, between cirrus and seminal vesicle, containing rather clear secretory granules coming from prostatic cells massed together immediately behind intestinal bifurcation as well as from those lying behind cirrus. Cirrus tubular, two-segmented at about middle and covered with diagonal muscle fibers, 32-58 ¡x long; proximal segment bell-shaped, 9-18 ¡x wide, distal segment narrower than proximal segment, slightly curved, occasionally bent back on itself, abruptly tapered distally. Genital pore median, shortly postbifureal. Ovary oval, 23-46 X 1 6 - 2 3 ¡x, immediately pretesticular. On the ventral side of the body near the vaginal aperture is a heavily sclerotized, semicircular fold. Vagina and vaginal duct forming a straight narrow tube

7°

DISCUSSION

42 HABITAT

HOLOTYPE DESCRIPTION

opening on right margin a short distance behind base of cirrus. Seminal receptacle elongated longitudinally. No eggs observed. Vitellaria co-extensive with intestine. This species is characterized by the two-segmented cirrus and the possession of a heavily sclerotized semicircular fold near the vaginal aperture. The specific name refers to the two-segmented cirrus.

Haliotrema bodiani n. sp.

FIGURE 42

Gills of Bodiatius bilunulatus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 115. (Based on 22 whole mounts.) Body flattened subcylindrical, 0.75-1.5 X 0.08-0.2 mm, with two pairs of eyespots. Opisthohaptor 0.2 mm wide in the type subjected to cover-glass pressure, well constricted off from body proper which is usually prolonged posteriorly into a stalk for the opisthohaptor and contains cement glands on each side, with two pairs of similar, indistinctly fenestrated anchors, 57-82 ¡x lineally from tip of longer root to height of curve of blade, two median transverse bars and several pairs of marginal hooklets about 15 ¡x long; dorsal root of dorsal anchor definitely longer than ventral root, ventral root of ventral anchor similarly longer than dorsal root. Dorsal bar slightly arcuate, with a pair of winglike submedian swellings on convex side and a small median knob, 3565 ¡x from end to end. Ventral bar with prominent wing-like protuberance anterolaterally, 40-68 ¡x from end to end. In front of the anchor apparatus is an inverted Y-shaped set of muscle bundles, the wide stem of which is divided into two bundles anteriorly, each bundle being continued forward into the ventral body wall. Head round, 65-100 ¡x in diameter, containing on each side a row of several swollen head organs. Eyespots often dissociated. Pharynx 27-50 X 22-63 ¡x; esophagus very short; ceca united behind testis and prolonged posteriorly to a cecum about 0.18 mm long in the type. Testis elliptical, 70-113 X 27-100 ¡x, equatorial. Vas deferens turning round left cecum and forming inverted claviform seminal vesicle anteriorly. Prostatic reservoir claviform, 50 X 20 ¡x, provided with oblique muscle fibers, situated longitudinally to left of cirrus. The ascending prostatic duct from the posterior prostatic cells opens into the anterior end of the prostatic reservoir. Cirrus 60-88 ¡x long, bipartite; proximal portion cylindrical, 10-15 M w ^ e , surrounded by oblique and circular muscle fibers forming a sheath for the cirrus; distal portion spiniform, pointed, provided with a semispiral membranous flange. Genital pore about 0.5 mm posterior to intestinal bifurcation in the type. Ovary elliptical or retort-shaped, immediately in front of testis or overlapping it. Vagina pyriform or saccular, 30-63 X 10-22 ¡x, opening close to or on right margin of body about halfway between base of cirrus and

Dactylogyiidae

DISCUSSION

43 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

71

ovary; vaginal duct originating from near vaginal aperture with a small bulbous swelling and running alongside vagina to near its base, where it leads into a delicate vaginal duct. No eggs observed. This species differs from the most closely related Haliotrema priacanthi n. sp. in body size and in the ventral haptoral bar being bifid laterally.

Haliotrema brotulae n. sp.

FIGURE 4 3

Gills of Brotula multibarbata (type host), Zebrosoma flavescens, Chromis ovalis, Parupeneus porphyreus and Melichthys vidua; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 116. (Based on 32 whole mounts.) Body plump, 0.44-0.76 mm long, up to 0.1-0.19 m m wide at testicular level. Opisthohaptor 80-150 wide at level of lateral projections, constricted off from body proper, with two pairs of fenestrated anchors of similar shape; ventral anchor 50-70 /x long from tip of prominent dorsal root to height of curve of blade; ventral bar 45-65 fi long, somewhat constricted at middle; dorsal anchor 50-65 fi long from tip of longer ventral root to height of curve of blade; dorsal bar 40-68 /x long, with paired transverse projections anterolaterally; marginal hooklet about 10 /i long. Head triangular or broadly rounded, 70-130 ¡j. wide, with three pairs of head organs. Eye pigment scattered. Pharynx 22-42 X 2235 n; esophagus about 25 ¡i long in the type; ceca united posterior to testis. Testis oval, 70-140 X 60-93 ¡1, postequatorial. Vas deferens wide, looping around left cecum, turning back on itself anteriorly and opening into base of cirrus, without forming definite seminal vesicle. Cirrus tubular, curved, 46-70 ¡i long, surrounded by circular muscle fibers at proximal portion, with two-lobed broad base 10-25 v- l° n g- Prostatic reservoir tubular, somewhat muscular, 40 X 10 ¡x in the type, situated longitudinally dorsal to cirrus, receiving duct from posterior group of prostatic cells before opening into base of cirrus. Genital pore to left of median line shortly behind intestinal bifurcation. Ovary elongate oval to elliptical, 42-80 X 20-47 equatorial. No eggs observed except in the specimens from Parupeneus porphyreus, in which the eggs, filamented at one end, measured 66-90 X 48-55 ¡i. Vagina retortshaped or pyriform, 30-58 X 10-28 ¡x, with thick wall of circular muscles, opening on right margin of body immediately behind level of base of cirrus; vaginal duct narrow, running obliquely backward, forming a small muscular bulb just before joining seminal receptacle. Seminal receptacle oval, 35 X 20 ¡i in the type, immediately behind transverse vitelline duct. Vitellaria co-extensive with intestine. This species bears a certain resemblance to Haliotrema cetitropygis n. §p. in general anatomy, especially in the structure of the cirrus, but differs from it in the structure of the vagina and the haptoral anchors and bars. It is to be noted that this species lodges in quite different fish hosts

72

(Brotulidae, Balistidae, Acanthuridae, Pomacentridae, and Mullidae) which have no phylogenetic relationship, probably because of the similar environments in which the hosts live.

44 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

45 HABITAT HOLOTYPE DESCRIPTION

Haliotrema

caesiopercae

n. sp.

FIGURE 4 4

Gills of Caesioperca thompsoni; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 1 7 . (Based on 1 5 whole mounts.) Body elongate, subcylindrical, 0.45-0.68 mm long, up to 60-120 ¡x wide at level of testis. Opisthohaptor 0.1 mm wide at level of lateral projections, with two pairs of non-fenestrated anchors, two dissimilar bars, and several pairs of marginal hooklets about 13/1 long; dorsal anchors 39-46 ¡x long lineally from tip of long dorsal root to height of curve of blade; dorsal bar flexed posterolaterad a little lateral to its middle, 51-58 ¡x long, with paired submedian lateral projections; ventral anchor 42-46 ¡x long lineally from tip of ventral root to height of curve of blade; ventral bar as long as dorsal bar, curved like this bar, but without submedian lateral projections. Head trapezoidal, 40-70 ¡x wide, with few pairs of head organs along lateral margins. Eyespots dissociated. Pharynx round, 18-25 diameter; esophagus very short; ceca united posteriorly. Testis oval to elliptical, 58-93 X 25-50 ¡x, at posterior end of middle third of body. Vas deferens looping round left cecum; seminal vesicle alongside prostatic reservoir, with its tapering distal end emptying into base of cirrus. Cirrus 37-65 ¡x long, broad-based, recurved, somewhat sigmoid, scoop-shaped distally, at posterior end of anterior third of body. Prostatic reservoir saccular, lying longitudinally alongside seminal vesicle. Prostatic cells divided into two (an anterior and a posterior) groups. Genital pore median, some distance posterior to intestinal bifurcation. Ovary elliptical, 30-80 X 18-40 fx, very slightly overlapping testis posteriorly. Vagina small, funnel-shaped, opening on right margin of body at about level of posterior end of cirrus; vaginal duct narrow, opening directly into fertilization chamber. No seminal receptacle. No eggs observed. Vitellaria co-extensive with intestine. This species differs from the most closely related Haliotrema chromidis n. sp., markedly in the absence of muscle lamella on the cirrus and slightly in the structure of the haptoral apparatus (dorsal anchor not fenestrated, dorsal bar more strongly curved).

Haliotrema canescem

n. sp.

FIGURE 4 5

Gills of Zanclus canescens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 118. (Based on 10 whole mounts.) Body small, elongate, 0.52-0.96 mm long,

Dactylogyridae

DISCUSSION

46 HABITAT

HOLOTYPE DESCRIPTION

73

up to 0 . 0 9 - 0 . 1 6 mm wide at level of testis. Opisthohaptor 7 5 - 1 3 8 ¡i wide at level of lateral projections, with two pairs of fenestrated anchors, two dissimilar bars, and few marginal hooklets up to 15 ^ long; dorsal anchor 4 2 - 5 0 ¡j. long lineally from tip of dorsal root to height of curve of blade; ventral root of this anchor very much reduced; dorsal bar 3 2 - 5 0 ¡x lineally from end to end, with both ends directed anterolaterally; ventral anchor 4 5 - 5 0 /j, long from tip of its very prominent ventral root to height of curve of blade, with dorsal root greatly reduced; ventral bar coathanger-shaped, 4 7 - 5 0 ¡1. long lineally from end to end. Head broadly rounded in front, with three pairs of head organs anterolaterally. Two pairs of eyespots present. Pharynx 17-30 p. in diameter; esophagus practically absent; ceca united behind testis. Testis oval, 1 0 0 - 1 6 3 x 5 ° - i ° ° postequatorial. Vas deferens looping around left cecum opposite vagina. Seminal vesicle inconspicuous, alongside prostatic reservoir. Cirrus about 6 5 - 9 5 /* l°ng> consisting of a bellshaped base and a laterally flanged narrow, apparently distorted, main shaft of irregular outline. Prostatic reservoir inverted retort-shaped, constricted near middle, 4 0 - 6 0 X 2 0 /A, surrounded by well developed prostatic cells. Genital pore median, postbifurcal. Ovary subspherical, 5 0 - 7 5 X 3 0 - 5 0 ¡1. No eggs observed. Vitellaria coextensive with intestine. Vagina subcylindrical, 5 0 - 6 3 X 1 5 - 2 5 ¡1, provided with longitudinal and circular muscles, opening close to right margin of body at junction of anterior with middle third of body; vaginal duct narrow, short. Seminal receptacle very small. Vitellaria co-extensive with intestine, sometimes intruding into opisthohaptor. This species is characterized by a cirrus which is narrow and irregular in outline. In this respect, as well as in the terminal genitalia, it resembles Haliotrema magnacantha n. sp., but it differs from the latter distinctly in the measurements of the anchors and bars, the ranges of which are entirely separate.

Haliotrema eentropygis n. sp.

FIGURE

46

Gills of Centropyge potteri; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 119. (Based on 1 2 whole mounts.) Body very small, 0 . 2 8 - 0 . 3 4 m m l°n8> U P to 5 0 - 8 0 ¡x wide at ovariotesticular level. Opisthohaptor well marked off from body proper, 7 0 - 8 5 /A wide at level of lateral projections; dorsal anchor fenestrated, 2 5 - 3 3 P from tip of very prominent dorsal root to height of curve of blade; dorsal bar shaped like a flattened letter M, 4 0 - 6 0 /x long; ventral anchor 2 5 - 3 0 /¿ long lineally from tip of ventral root to height of curve of blade; ventral bar only slightly curved submedianly, 3 7 - 5 5 long; marginal hooklet 1 0 ¡i long. Head trapezoidal, 2 7 - 4 3 p wide, with few head organs. No eyespots. Pharynx 15-23 X 12-20 ¡i; ceca united posterior to testis.

74

DISCUSSION

47 HABITAT

HOLOTYPE DESCRIPTION

Testis oval, 35-50 X 20-50 ¡x, at junction of middle with posterior third of body. Vas deferens looping around left cecum just anterior to level of ovary, bending back on itself to form an inverted retort-shaped seminal vesicle. Cirrus 2-segmented, C-shaped as a whole, 12-23 f- lineally from end to end, 6.5-7.5 ¡i wide at its enlarged basal segment; its terminal opening on anterior face of its blunt point. Prostatic reservoir elliptical, between seminal vesicle and cirrus, with prostatic cells in front. Genital pore median, immediately postbifureal. Ovary elliptical, 27-38 X 10-25 p, equatorial, may be separated from testis by a strand of vitelline follicles. No eggs observed. Uterus showing finely granulated epithelia. Vagina tubular, narrow, non-muscular, opening ventral to right cecum behind level of base of cirrus; vaginal duct not clearly delimited from vagina. Seminal receptacle overlapping anterior part of ovary. Vitellaria co-extensive with intestine. This species differs from the most closely related Haliotrema angulare n. sp. in the cirrus lacking the accessory spine near its base, in the characters of the vagina, and in the origin of the vaginal duct, and differs from Haliotrema rectangulare n. sp. in the cirrus not being enclosed in a sheath of transverse muscle fibers and in the absence of the posterior group of prostatic cells.

Haliotrema

chelicirrvs n. sp.

FIGURE 47

Gills of Holocentrus lacteoguttatus (type host), H. scythrops and H. sammara; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 120. (Based on 28 whole mounts.) Body flattened subcylindrical, 0.4-0.7 mm long, 0.08-0.15 mm wide at different levels according to state of contraction. Opisthohaptor well constricted off from body proper, not very prominent laterally, 74-140 /x wide, with few pairs of larval hooklets 11-15 P long laterally and one pair posteriorly; dorsal anchor 35-54 long lineally from tip of very long dorsal root to height of curve of blade; dorsal bar almost straight, 27-56 n long, with paired anterolateral projections; ventral anchor 37-51 ¡x long lineally from tip of prominent ventral root to height of curve of blade; ventral bar arcuate or V-shaped, 25-49 lineally from end to end. Head broadly rounded or trapezoidal, 42-110 p wide, with several pairs of head organs along its sloping margin. Eyespots granules dissociated. Pharynx 23-35 x 20-30 fi; esophagus very short; ceca united posterior to testis. Testis elliptical, 50-116 X 28-70 //., postequatorial. Vas deferens looping around left cecum at anterior part of middle third of body, bending back on itself anteriorly to form fusiform seminal vesicle. Copulatory organ approximately cheliform, surrounded by strong muscle fibers from base to near tip, 27-46 ¡x long lineally, with ledge-like projection laterally close to its point of cylindrical cirrus proper; the other prong opposite the cirrus

Dactylogyridae

DISCUSSION

48

HABITAT HOLOTYPE DESCRIPTION

75

proper is provided with a cup at tip and enlarged toward its base, where it encloses a vestibular chamber for the cirrus proper. Common genital pore surrounded by a bulb of concentric lamellar muscle fibers, opening midventrally immediately behind intestinal bifurcation. Prostatic cells divided into two groups; prostatic reservoir inverted claviform, dorsal or anterodorsal to cirrus. Ovary longitudinally elongated elliptical or oval, 2 3 - 7 5 X 2 1 - 4 5 /*> e ( l u a " torial, immediately pretesticular. No mature eggs observed. Vitellaria coextensive with intestine. Vagina funnel- or cup-shaped, sclerotized, opening on right margin of body at about junction of anterior with middle third of body; vaginal duct narrow, arising terminally from vagina. No distinct seminal receptacle. This species is unique in possessing a cheliform copulatory organ and a sphincter-like muscle bulb at the genital pore, by which it is easily distinguished from any other known members of the genus. The specific name refers to the cheliform cirrus.

Haliotrema

chromidis

n. sp.

FIGURE 4 8

Gills of Chwmis ovalis; Hawaii. U.S. Nat. Mus Helm. Coll., S.Y. No. 1 2 1 . (Based on 2 0 whole mounts.) Body elongate, 0 . 3 2 - 0 . 5 mm long, up to 5 0 - 1 0 0 ix wide in midregion or at testicular level. Opisthohaptor 6 5 - 1 2 5 ¡x wide at level of lateral projections; dorsal anchor fenestrated, 3 2 - 6 3 ¡x long from tip of dorsal root to height of curve of blade; ventral root reduced, conical; dorsal bar thick, arcuate, 3 5 - 6 3 ¡x long; ventral anchor not fenestrated, 4 0 - 5 6 fx long from tip of longer ventral root to height of curve of blade; dorsal root of this anchor reduced to rounded protuberance; ventral bar slender, arcuate, 4 0 - 7 3 ¡x long; marginal hooklet about 1 2 . 5 ¡x long. Head trapezoidal, 3 7 - 5 6 ¡x wide, with few head organs along sloping lateral margin. No eyespots. Pharynx 15-23 X 12-21 ¡x. Ceca united posteriorly in anterior half of posterior third of body. Testis oval, 3 1 - 8 1 X 2 2 - 4 7 /*» postequatorial. Vas deferens turning round left cecum, forming seminal vesicle after bending back on itself anteriorly. Copulatory organ 2 5 - 4 2 ¡x long lineally, tubular, two-segmented, tapering distally, curved at nearly right angles, where a small spicular hook is attached, with its point projecting out of genital pore. Around the enlarged base of the cirrus is a sheath of circular muscle fibers; distal to this sheath is another band of fine oblique muscle fibers arising from the basal portion of distal segment and attached to the distal end of this segment. Prostatic reservoir 15-28 X 9-14 ¡x, situated longitudinally alongside cirrus, with its anterior end surrounded by prostatic cells. Genital pore a little behind intestinal bifurcation. Ovary longitudinally elongate, 2 5 - 3 9 x equatorial. Vagina tubular, opening on right margin of body about halfway between cirrus and

76

DISCUSSION

49 HABITAT

HOLOTYPE DESCRIPTION

DISCUSSION

50 HABITAT HOLOTYPE DESCRIPTION

ovary or a little more anteriorly. Seminal receptacle small, oval. No eggs observed. Vitellaria co-extensive with intestine. The present species is characterized by a spicular hook at the point of bending of the cirrus.

Haliotrema ctenochaeti n. sp.

FIGURE 4 9

Gills of Ctenochaetus strigosus (type host) and Acanthurus nigrofuscus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 122. (Based on 10 whole mounts.) Body elongate fusiform, 0.47-0.84 mm long, up to 0 . 1 - 0 . 1 7 mm wide in midregion. Opisthohaptor 0 . 1 2 - 0 . 1 9 mm wide, with a slender stalk; dorsal anchor fenestrated, 5 2 - 7 3 ¡x long lineally from tip of long dorsal root to height of curve of blade; dorsal bar coathanger-shaped, 5 7 - 6 5 ¡x long; ventral anchor 6 0 - 7 0 ¡x long lineally from tip of prominent ventral root to height of curve of blade; ventral bar with a posterior swelling near each end, 5 2 - 7 0 ¡x long; marginal hooklets 12.5 p. long. Head broadly rounded, 50-90 ¡x wide, with two pairs of ceca eyespots. Pharynx 2 5 - 3 3 X 1 7 - 3 5 united posterior to testis. Testis rounded, 7 5 - 1 7 5 x 3 7 - 7 5 /i, approximately equatorial. Vas deferens looping around left cecum at level of base of vagina, and then turning back on itself near tip of cirrus. Cirrus tubular, 6 0 - 7 0 ¡x. long, gently curved, narrowly flanged, 10 ¡x wide at its bell-shaped base, enlarged a little at tip in form of a small funnel, provided with a spiniform accessory branch proximal to its middle. Prostatic reservoir inverted claviform, up to 12-18 fx wide near its anterior end; prostatic cells well developed in postbifurcal field. Genital pore midventral, shortly postbifurcal. Ovary oval, 3 5 - 7 5 X 2 7 - 3 8 ¡x, immediately pretesticular. No eggs observed. Vagina cylindrical, muscular, 4 5 - 6 3 X 1 5 - 2 5 ¡x, opening on right body margin a little behind cirrus, 0.26 mm from head end in the type 0.84 mm long; vaginal duct very short, arising from base of vagina. A small elongate seminal receptacle present. Vitellaria co-extensive with intestine. This species is characterized by the cirrus being enlarged at the tip and is provided with a cuticular fold for its greater part. It is distinguished from the most closely related Haliotrema macracantha n. sp. by the haptoral anchors being definitely smaller.

Haliotrema curvicirrus n. sp.

FIGURE 50

Gills of Farupeneus porphyreus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 123. (Based on 12 whole mounts.) Body flattened subcylindrical, 0.5-0.72 mm in length, with maximum width of 0 . 1 2 - 0 . 1 8 mm at level of testis or a

Dactylogyridae

DISCUSSION

51 HABITAT HOLOTYPE DESCRIPTION

77

little behind it. Opisthohaptor well constricted off from body proper, J 1 0 0 - 1 2 5 l - wide; dorsal anchor 6 2 - 6 8 ¡x long lineally from tip of long dorsal root to height of curve of blade; dorsal bar slender, bifid at both ends, 4 7 - 5 5 ju. long; ventral anchor 5 2 - 6 5 long lineally from tip of ventral root to height of curve of blade; ventral bar somewhat swollen submedianly, 4 5 - 6 0 ¡u, long; marginal hooklets about 1 0 ¡x long. Head flattened trapezoidal, 6 5 - 1 0 5 p. wide. Eyespots dissociated. Pharynx 2 7 ceca 38 X 2 7 - 3 5 united posterior to testis. Testis rounded to elliptical, 8 7 - 1 2 5 X 3 5 - 1 0 0 ¡x, at junction of middle with posterior third of body. Vas deferens looping around left cecum, making an inverted U-turn before opening into base of cirrus. Cirrus consisting of a sclerotized basal ring 2 3 - 3 0 ¡x long by 1 5 - 2 3 ¡x wide, and a tubular main portion which is 9 3 - 1 1 5 ¡x long and more or less undulating proximally but bent at nearly right angles near its distal end. Prostatic reservoir inverted claviform, 4 0 - 6 5 X 1 0 - 2 0 ¡x, with its tapering posterior end joining duct from posterior prostatic cells which extend into the extracecal fields posterior to vagina. The duct from the posterior prostatic cells is occasionally distended with secretion like a reservoir. The anterior prostatic cells extend also in the inter- and extra-cecal fields. Ovary oval, 5 0 - 5 5 X 3 5 - 4 0 ¡x, equatorial or postequatorial. Eggs elliptical, 9 0 - 1 0 5 X 4 2 - 5 0 ju.; polar filament not fully developed in the eggs observed. Vagina saccular in the type, 5 0 - 6 0 ¡x long, opening ventrally close to right margin of body at level of posterior end of basal plate of cirrus; vaginal duct narrow, short. Seminal receptacle small, oval. Vitellaria extending further backward than cecal ends to near base of opisthohaptor. This species is easily distinguished from Haliotrema bifurcocirrus n. sp., which is often found associated with it, because the cirrus is not bifurcate.

Haliotrema epinepheli n. sp.

FIGURE 5 1

Gills of Epinephelus quernus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 2 4 . (Based on 2 1 whole mounts.) Body elongate fusiform to subcylindrical, 0 . 7 - 1 . 1 mm in length, with maximum width of 0 . 1 1 - 0 . 2 1 mm at middle third. Opisthohaptor 0 . 1 1 - 0 . 2 mm wide, well set off from body proper; dorsal anchor 5 5 - 6 3 long lineally from tip of longer dorsal root to height of curve of blade; dorsal bar bifid at each end, 3 0 - 5 5 ¡x long; ventral anchor 5 2 - 7 2 ¡x long lineally from tip of ventral root to height of curve of blade; ventral bar constricted at swollen middle portion, 32-51 ¡x long; marginal hooklets 15-17 /x long, set on prominent conical base. Six pairs of cement glands strongly developed immediately behind posterior end of vitellaria. Head 5 7 - 1 0 0 ¡x wide, with two pairs of small lobes containing head organs. Eyespots dissociated. Pharynx 1 0 - 4 3 X 2 3 - 4 6 ¡x; esophagus practically absent; ceca confluent posteriorly.

7

8

Testis rounded, 7 5 - 2 3 0 x 6 0 - 1 6 0 ¡x, in posterior part of middle third of body. Vas deferens looping around left cecum, forming seminal vesicle just medial to left cecum and another smaller vesicle further anteriorly before turning backward. Cirrus 5 2 - 6 3 ¡x long, swollen at base set on a semicircular sclerotized pad which is very much thickened on one side as shown in the figure. It is enclosed for the greater proximal portion in a thick sheath of circular muscle fibers, with its distal end recurved, lying obliquely in median field of posterior part of anterior third of body. There are two prostatic reservoirs; longer ventral one 6 2 - 9 0 x 11-26 containing rather coarse granules; shorter dorsal one 5 4 - 7 0 X 1 4 - 3 5 /i, with very fine granules and appearing transparent; both situated oblique-longitudinally close parallel to each other along right side of cirrus. Prostatic cells for each reservoir divided into two groups; those for the clear shorter reservoir divided into subsymmetrical groups; the duct from the posterior group of prostatic cells empties into the anterior end of the longer reservoir. Genital pore about 0.1 mm behind intestinal bifurcation in the type 0.93 mm long.

p,

Ovary elliptical, situated a little to right of median line immediately in front of testis. Eggs in utero one at a time, oval, flattened on one side, 6 3 - 7 7 A1 l°ng> with winding filament 7 0 - 1 0 0 p long at its posterior end. Vagina with sclerotized bulbous swelling up to 40 /x wide at middle, opening on right margin of body about halfway between cirrus and ovary; vaginal duct arising from tapering inner end of vagina. Seminal receptacle oval, 2&~37 x 2 3 - 3 2 between ovary and transverse vitelline duct. Canalis receptaculi seminis very long, arising from right side of seminal receptacle, crossing left cecum ventrally, and running backward sinuously to disappear at the level of testis. This species is characterized by the possession of an unusually long canalis receptaculi seminis and by the structure of the vagina. The presence of two prostatic reservoirs, each of which has two groups of prostatic cells, is another differentiating feature.

¡i,

DISCUSSION

52. Haliotrema flagellatum n. sp. HABITAT HOLOTYPE DESCRIPTION

FIGURE 52

Gills of Chaetodon fremblii (type host) and C. corallicola; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 2 5 . (Based on 1 6 whole mounts.) Body elongate, 0.25-0.6 mm long, up to 0.04-0.1 mm wide at testicular level. Opisthohaptor well constricted off from body proper, 4 5 - 1 2 5 ¡x wide at level of lateral projections, with two pairs of fenestrated anchors 3 0 - 5 4 ¡x long lineally, two almost similar bars, and several pairs of marginal hooklets 12-13 f- l° n g; dorsal bar slightly curved, 3 5 - 5 4 long; ventral bar 3 0 - 5 3 ¡x long, with its ends directed posterolateral^. One or two pairs of eyespots. Head trapezoidal or 4-lobed, 25-75 P base. Pharynx spherical, 1 3 - 3 0 X 1 1 - 3 0 /*; ceca united behind testis.

Dactylogyridae

DISCUSSION

53

HABITAT

79

Testis oval to elliptical, 23-100 X 13-60 n, situated behind middle of body. Vas deferens turning round left cecum, looping upon itself, and then running toward base of cirrus without forming definite seminal vesicle. Copulatory organ up to 45 long, consisting of a bell-shaped base 10-20 ¡í wide and enclosed in a sheath of circular muscles, a whiplike cirrus proper, and a very fine sigmoid accessory filament arising from base of cirrus proper. Prostatic reservoir small, elongate, alongside cirrus. Genital pore just postbifurcal. Ovary elongate, contiguous with testis, 11-50 X 10-45 P- Only one shrunken egg 55/1 wide without filament was seen in the uterus of one specimen. Seminal receptacle present. Vitellaria entirely co-extensive with intestine. Vagina reduced to a very small, funnel-shaped structure opening on right margin of body at about level of base of cirrus; vaginal duct very fine throughout. This species is characterized by its small size and by the cirrus proper being whip-like; hence the specific name.

Haliotrema

flexicirrus

n. sp.

FIGURE

53

Gills of

Acanthurus nigroris (type host), A. tiigrofuscus and A. leucoHawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 126. (Based on 45 whole mounts.) Body elongated subcylindrical, 0.3-0.8 mm long, up to 40-110 /i wide at level of testis. Opisthohaptor 70-150 ¡x wide, well constricted off from body proper, with two pairs of fenestrated anchors, two coathanger-shaped bars, and few marginal hooklets 10-13 Plong. Dorsal anchor 50-68 ¡i long lineally from tip of dorsal root to height of curve of blade; dorsal bar 46-85 /i long, thicker than ventral bar; ventral anchor 39-75 ^ long lineally from tip of ventral root to height of curve of blade; ventral bar 35-85 ¡l long. Head 2-lobed on each side, 28-58 ¡x. wide, with few pairs of head organs. Eyespots dissociated or compact. Pharynx 11-28 X 12-25 /*> situated at posterior end of middle third of body or at its junction with posterior third. Vas deferens looping around left cecum, turning backward near genital pore. Cirrus tubular, widened at base, near which it turns back on itself and then assumes a C shape, measuring 45-65 long along its axis. Prostatic reservoir saccular, 25-45 x 10-28 ¡x, largely in concavity of cirrus, with prostatic cells in front. Genital pore shortly postbifurcal. pareius;

HOLOTYPE DESCRIPTION

Ovary oval to elliptical, 23-75 x /*> overlapping testis posteriorly or not, just postequatorial. Vagina saccular, or subcylindrical to retortshaped, muscular, but relatively thin-walled, 30-50 X 11-28 opening close to right margin of body just behind level of base of cirrus; vaginal duct zigzag, arising from right side of vagina a little away from its posterior end. Seminal receptacle elongate pyriform. No eggs observed. Vitellaria co-extensive with intestine.

8o

DISCUSSION

54 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

55 HABITAT HOLOTYPE

This species is characterized by the cirrus always being flexed back on itself near the base and C-shaped elsewhere. The specific name refers to this feature.

Haliotrema lactoriae n. sp.

FIGURE 54

Gills of Lactoria diaphanus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 2 7 . (Based on 1 0 whole mounts.) Body rather plump, subcylindrical, 0 . 5 8 0.85 mm long, up to 90-150 /i wide at ovariotesticular level. Opisthohaptor 90-120 fi wide; dorsal anchor 45-63 ¡x from tip of very prominent dorsal root to height of curve of blade, with ventral root greatly reduced; dorsal bar 45-63 long, with paired submedian protuberances on anterior face; ventral anchor fenestrated, 44-58 ¡x long from tip of ventral root to height of curve of blade; dorsal root of this anchor rather broadly rounded; ventral bar coathanger-shaped, 41-56 ¡x long; marginal hooklets up to 15 ft long. Head 40-90 ¡x wide, with two pairs of inconspicuous lobes and three or more pairs of head organs. No compact eyespots. Pharynx small, 16-45 x J 6~43 m esophagus very short; ceca united posterior to testis. Testis oval to elliptical, often smaller than ovary, 50-100 X 25-50 ¡x, postequatorial. Vas deferens looping around left cecum, forming an inverted U-turn dorsal to cirrus. Seminal vesicle indistinct. Cirrus 50-80 ¡x long, approximately dagger-shaped, with its blade ornamented by a spiral fold except for its tip; its basal handle 25-30 ¡x long, tapered posteriorly, provided throughout its length with an outer sheath of longitudinal muscle fibers and a very thick inner coat of circular muscle fibers. To the spiral fold of the cirrus are attached two curved filamentous spicules, whose rod-shaped common base extends to the base of the blade of the cirrus. Prostatic complex relatively poorly developed anterodorsal to cirrus. Genital pore median, a little postbifurcal. Ovary elongate, oval, 23-125 X 18-65 l1' immediately pretesticular, usually more or less overlapping testis. No eggs observed. Vagina tubular, funnel-shaped at its opening, 30-50 ¡x long, a little posterior to base of cirrus. Seminal receptacle oval, 20-37 x 12-23 Vitellaria co-extensive with intestine. This species is characterized by the cirrus being dagger-shaped and ornamented on its blade with a spiral fold and two filamentous spicules.

Haliotrema macracantha n. sp.

FIGURE 55

Gills of Acanthurus nig),oris (type host), A. thompsoni, Zebrasoma veliferum and Z. flavescens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 2 8 .

Dactylogyridae

DESCRIPTION

DISCUSSION

56 HABITAT HOLOTYPE DESCRIPTION

81

(Based on 20 whole mounts.) Body elongate, subcylindrical, 0 . 4 6 - 1 . 0 3 mm long, up to 0.06-0.19 mm wide in midregion. Opisthohaptor 80-200 ¡x wide at level of lateral projections; dorsal anchor 55-84 ¡x long lineally from tip of very prominent dorsal root to height of curve of blade, indistinctly fenestrated; ventral root of this anchor reduced to flat prominence; dorsal bar arched, with its swollen ends recurved, 40-95 long; ventral anchor 55-83 p long from tip of ventral root to height of curve of blade, with a rudimentary window basally; its shaft much stronger than that of dorsal anchor; ventral bar 42-80 ¡x long, coathanger-shaped; marginal hooklets 9-15 ¡x. long. Head trapezoidal or trilobate, 32-105 ¡x wide, with well developed head organs. Two pairs of compact eyespots anterior or anterodorsal to pharynx. Pharynx 15-46 X 13-35 & esophagus practically absent; ceca united posteriorly in anterior part of posterior third of body. Testis oval to elliptical, 62-186 X 25-86 ¡x, situated in middle third or at junction of middle with posterior third of body. Vas deferens wide, looping around left cecum opposite vagina, turning back on itself anteriorly and forming inconspicuous seminal vesicle. Cirrus arcuate, 55-100 p long, bell-shaped at base up to a width of 13-15 distal part flanged spirally, apparently distorted, terminating in a cap-like enlargement. Prostatic reservoir divided into two (an anterior and a posterior) portions, up to 13-20 p wide, lying longitudinally alongside cirrus; prostatic cells divided into two (an anterior and a posterior) groups. Genital pore midventral, a little posterior to intestinal bifurcation. Ovary ovoid, 35-100 X 20-50 ¡x, overlapping testis posteriorly. Vagina fusiform to subcylindrical, muscular, 25-75 x 1 0 _ 2 8 opening ventrally close to right margin of body just posterior to base of cirrus; vaginal duct short, arising terminally from posterior end of vagina. No eggs observed. Vitellaria co-extensive with intestine. This species resembles Haliotrema canescens n. sp. from Zanclus canescens very closely, but differs distinctly in that the haptoral anchors and bars are much larger, although they are similar in shape. The specific name refers to this character.

Haliotrema microphallus n. sp.

FIGURE

56

Gills of Chaetodon ornatissimus (type host) and C. miliaris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 129. (Based on 18 whole mounts.) Body slender, subcylindrical to plump, 0.25-0.68 mm in length, with maximum width of 0.045-0.16 mm in midregion. Opisthohaptor 58-140 ¡x wide at level of lateral projections, well marked off from body proper; dorsal anchor fenestrated, 34-55 plong from tip of dorsal root to height of curve of blade; ventral root of this anchor almost completely reduced; dorsal bar with paired submedian swellings, 45-53 /x long; ventral anchor also fenestrated, 37-49 /x long from tip of prominent ventral root to height of curve of blade, with its ventral

82

DISCUSSION

57 HABITAT HOLOTYPE DESCRIPTION

root much longer than dorsal root; ventral bar coathanger-shaped, 3 7 - 5 3 long; marginal hooklets 10-13 n long. Head trapezoidal or 2-lobed, 25-75 wide, with well developed head organs. Two pairs of eyespots anterior to pharynx. Pharynx 17-35 X 11-28 n; esophagus very short; ceca united posterior to testis. Testis elliptical to oval, 3 2 - 8 5 X 1 1 - 5 0 ¡x, postequatorial or at junction of middle with posterior third of body. Vas deferens turning round left cecum, forming a small seminal vesicle on left side of cirrus. Cirrus tubular, 13-32 ¡i long, consisting of a bell-shaped base, an arcuate main shaft, and a spicular apical piece. Prostatic reservoir longitudinally elongated, small (only 3.5-4 fi wide), with prostatic cells around its anterior end as well as posterior to base of cirrus. Genital pore midventral, a short distance posterior to intestinal bifurcation. Ovary longitudinally elongated to oval, 2 3 - 7 5 x 1 5~ 2 ° f> immediately pretesticular. No eggs observed. Vagina indistinct, opening ventrally close to right margin of body in form of a cup-shaped enlargement, a short distance posterior to cirrus; vaginal duct running straight backward and inward. Seminal receptacle small, oval, 10-12 X 5-9 ¡1. Vitellaria co-extensive with intestine. This species differs from the most closely related Haliotrema scyphovagina n. sp. from Chaetodon miliaris in the vagina being very poorly developed. In H. scyphovagina the vagina forms a large bowl-shaped structure.

Haliotrema minutospirale n. sp.

FIGURE 5 7

Gills of Paraupeneus chryserydros (type host), P. pleurostigma and P. multifasciatus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 3 0 . (Based on 2 1 whole mounts.) Body very small, rather plump, constricted in vaginal region, 0 . 4 8 - 0 . 7 X 0 . 0 9 - 0 . 1 6 mm. Opisthohaptor slightly constricted off from body proper, 9 0 - 1 2 5 p wide; dorsal anchor 5 2 - 6 8 ¡1. lineally from tip of longer dorsal root to height of curve of blade; dorsal bar straight, with uneven surface anteriorly, 3 7 - 5 0 long; ventral anchor 4 5 - 6 5 fi, long lineally from tip of longer ventral root to height of curve of blade; ventral bar V-shaped, 3 7 - 5 8 ¡x lineally from end to end; its slightly outcurved arms with paired submedian prominences; marginal hooklets 10-15 A1 l° n g- Head with two pairs of more or less prominent lobes, sometimes almost truncate, 6 0 - 1 0 0 ¡n. wide; each lobe with head organ. Eyespots absent. Pharynx globular, 2 2 - 3 3 X 2 2 - 3 5 f-' esophagus very short; ceca united posteriorly. Testis oval, 6 0 - 1 2 5 x 37~9° postequatorial. Vas deferens swollen as it turns round left cecum. Seminal vesicle inverted claviform, situated longitudinally between left cecum and prostatic reservoir. Cirrus 7 0 - 1 0 5 ¡i long, consisting of an anterior, spiral, flanged portion and a posterior, cylindrical portion which is 3 0 - 4 5 ¡i long by 1 0 - 1 3 P- wide and enclosed

Dactylogyridae

DISCUSSION

58 HABITAT HOLOTYPE DESCRIPTION

83

in sheath of circular muscle fibers. Prostatic reservoir inverted claviform, provided with thick wall of diagonal muscle fibers, lying longitudinally between seminal vesicle and cirrus. Prostatic cells very strongly developed in extracecal field in addition to intercecal field in contrast with those in Haliotrema spirale n. sp. Genital pore median, immediately postbifurcal. Ovary oval, 3 0 - 5 5 X 2 5 - 4 5 /*> n e arly equatorial, a little to right of median line. Vagina shaped like a cylindrical bottle, 4 0 - 9 0 j«. long, 1 7 - 3 5 y. wide at main cylindrical portion, the inner end of which is produced in form of a knob, opening on right margin of body, shortly posterior to base of cirrus. Vaginal duct arising from this knob dorsally, sigmoid, narrow. Seminal receptacle oval, 20 X 18 ^ in the type. Only one uterine egg seen, too much shrunken for measurement. Vitellaria co-extensive with intestine. This species resembles Haliotrema spirale n. sp. so closely that a careful comparison is necessary. The chief difference is in the entirely separate ranges of the cirrus length. The specific name refers to the smaller size of the spiral cirrus.

Haliotrema palmatum n. sp.

FIGURE 5 8

Gills of Acanthurus dussumieri (type host) and A. mata; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 131. (Based on 1 5 whole mounts.) Body flattened subcylindrical, 0 . 7 5 - 1 . 1 2 X 0 . 0 9 - 0 . 1 3 mm. Opisthohaptor 1 1 5 - 1 7 5 ¡x wide at level of lateral projections; dorsal anchor fenestrated, 6 5 - 8 8 ¡1 long from tip of prominent dorsal root to height of curve of blade, with its ventral root very much reduced; dorsal bar 5 5 - 8 0 p. long, with a distinct sinus ventromedianly and a pair of minute, horn-like, submedian projections anterolaterally; ventral anchor 6 5 - 8 8 ¡i long from tip of ventral root to height of curve of blade, with its dorsal root broadly flattened or rounded; ventral bar 5 2 - 8 2 ¡x long, with its lateral arm extending transversely at nearly right angles to median portion which has rough surface anteriorly; marginal hooklets about 12-13 p long. Head trapezoidal, 6 5 - 1 0 0 ¡t. wide, with three pairs of head organs. Head glands extending along each side of body further backward than pharynx. No eyespots. Pharynx 2 8 - 5 0 X 2 3 - 4 5 /»J esophagus up to 40 ¡x long when extended; ceca united posteriorly at about middle of posterior third of body. Testis elliptical to oval, postequatorial, 8 1 - 1 6 2 X 4 2 - 6 0 ¡x. Vas deferens moderately wide, swollen as it turns round left cecum dorsally, finally bending back on itself to form indistinct seminal vesicle, which lies alongside the prostatic reservoir. Cirrus tubular basally, but expanded unilaterally for its greater part in form of a palmate wing, 9 0 - 1 4 0 ¡x long lineally from end to end; its base a little flared and connected on each side with a heavily sclerotized piece, of which the right one is only 15 ¡x long and the left one is twice as long and directed forward. Prostatic cells

84

DISCUSSION

59 HABITAT HOLOTYPE DESCRIPTION

massed together anterior as well as posterior to cirrus. Prostatic reservoir inverted claviform, small, 35-40 x 10-13 ¡x, between above mentioned longer sclerotized piece and seminal vesicle. Genital pore a little postbifurcal. Ovary longitudinally elongated, 46-88 X 2 3 - 3 8 ¡x, equatorial. Vagina subcylindrical to claviform, muscular, 6 0 - 7 5 x 1 0 - 2 2 opening on right margin of body at level of base of cirrus, giving narrow vaginal duct at its posterior end. A small elongate seminal receptacle present. No eggs observed. Vitellaria co-extensive with intestine. This species is easily distinguished from any other known species of the genus by the peculiar palmate shape of the cirrus.

Haliotrema pervagoris n. sp.

FIGURE 59

Gills of Pervagor spilosoma; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 132. (Based on 20 whole mounts.) Body small, elongate, tapered anteriorly and in front of opisthohaptor, 0.45-0.66 mm in length, with maximum width of 0.06-0.14 mm in testicular region. On the ventral side of the body posterior to the cirrus is a shallow pouch or pit of varying size. This pouch encloses the vaginal pore when extended as in the type, but the two structures may sometimes appear separate because the connection between the two is obscured. I propose to call this pouch "circumvaginal pouch" ( C V ) . Opisthohaptor 115-170 ¡x wide at level of lateral projections bearing marginal hooklets 11-12 ¡x long; dorsal anchor rather slender, 4 2 - 7 0 /i long from tip of longer dorsal root to height of curve of blade; dorsal bar 6 3 - 7 7 >*• l° n & coathanger-shaped like ventral bar which is 58-84 /A long; ventral anchor 5 1 - 7 0 ¡x long from tip of ventral root to height of curve of blade. Head trapezoidal, 4 0 - 7 0 ¡x wide, with three pairs of head organs laterally. No eyespots. Pharynx subglobular, 18-28 X 14-28 ¡x; esophagus short; ceca united behind testis. Testis ovoid, 58—98 X 3 5 - 1 0 7 ¡x, situated at junction of middle with posterior third of body. Vas deferens looping around left cecum, bending back on itself between left cecum and prostatic reservoir to form an elongate slender seminal vesicle 5-12 ¡x wide. Cirrus stout, enlarged at obliquely truncated base, curved toward its middle at nearly right angles and then terminating in a spoon-shaped dilatation, 4 6 - 7 7 ¡x long lineally, 18-32 ¡x wide at base, well provided with muscle fibers which form a pad-like thickening above the swollen base. Prostatic reservoir inverted claviform, 7-16 ¡x wide, receiving at its base the ascending prostatic duct draining posterior group of prostatic cells. Genital pore postbifurcal, near posterior end of anterior third of body. Ovary subglobular to oval, 3 5 - 7 0 X 1 8 - 5 4 immediately pretesticular. No eggs observed. Vitellaria co-extensive with intestine, with its main

Dactylogyrìdae

DISCUSSION

60 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

85

bulk at intestinal bifurcation. Vagina constricted at its junction with vaginal duct, opening ventral to right cecum. Seminal receptacle ovoid. This species is characterized by the cirrus which is strongly curved and terminates in a spoon-shaped dilatation and by possession of a circumvaginal pouch.

Haliotrema priacanthi n. sp.

FIGURE 60

Gills of Priacanthus cruentatus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 133. (Based on 32 whole mounts.) Body subcylindrical, constricted in region of vagina, 0 . 5 5 - 0 . 8 2 mm long by 0 . 0 9 - 0 . 1 5 mm wide. Opisthohaptor not very well marked off, 0 . 0 7 6 - 0 . 1 4 mm wide, with two pairs of inconspicuously fenestrated anchors, two dissimilar bars, and several pairs of marginal hooklets about 1 2 . 5 p, long; dorsal anchor 4 6 - 5 5 ¡x long from tip of dorsal root to height of curve of blade; dorsal bar with a pair of submedian prominences anteriorly, and anterolaterally directed arms; ventral anchor 4 2 - 5 4 ¡k long from tip of ventral root to height of curve of blade; ventral bar 3 9 - 5 6 fi long, with paired submedian prominences anteriorly. Head trilobate, rounded at apex, with several pairs of head organs. Eyespots of two pairs or dissociated. Pharynx 2 5 - 4 0 X 2 5 - 4 0 /*; esophagus practically absent; ceca united posteriorly some distance behind testis. Testis oval to elliptical, 8 0 - 1 2 3 x situated at posterior end of middle third of body. Vas deferens looping around left cecum at level of vagina, bending back on itself anteriorly to form inconspicuous seminal vesicle overlapping prostatic reservoir. Cirrus 6 0 - 8 0 /i long, consisting of a cylindrical base 2 0 - 3 0 ¡j. long by 11-16 /x wide and a straight shaft tapering anteriorly and provided with a spiral sheath-like fold. Prostatic reservoir claviform, 6 0 - 8 0 X 1 1 - 2 3 ¡i, parallel to cirrus on its right side, provided with diagonal muscle fibers, receiving at its base the ascending prostatic duct from posterior group of prostatic cells lying behind base of cirrus. Prostatic cells divided into two (an anterior and a posterior) groups. Genital pore just postbifurcal. Ovary elliptical, 3 5 - 1 0 0 X 1 8 - 7 5 ¡i, overlapping testis posteriorly. Vagina pyriform to subcylindrical, transverse, 18-50 X 15-26 ¡x, provided with weak muscle fibers, opening ventrally close to right margin of body a little anterior to transverse vitelline duct; vaginal duct narrow, arising close to vaginal pore. Only one egg observed, pyriform, more or less constricted near narrower end, 125 X 52 ^ with very short rigid filament at narrower pole. Vitellaria co-extensive with intestine. This species very closely resembles Haliotrema bodiani n. sp. in the structure of the cirrus and in the disposition of the prostatic reservoirs, but it differs in body size and in the ventral bar not being bifid laterally.

86

61 HABITAT HOLOTYPE DESCRIPTION

Haliotrema pterophallus n. sp.

FIGURE 6 1

Gills of Centropyge potteri (type host), Chromis verator, C. ovalis and Pomacentrus jenkinsi; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 134. (Based on 46 whole mounts.) Body slender, subcylindrical, 0.3-0.95 mm in length, with maximum width of 60-160 //, at level of testis or cirrus, tapering posteriorly and forming a narrow stalk for opisthohaptor. Immediately behind the vaginal pore is an uvula-like lobe, postvaginal lobe (PV), projecting anterolaterad from right margin of body. Opisthohaptor 70170 ¡x wide at level of lateral projections; dorsal anchor with large basal window, 23-58 /x long lineally from tip of dorsal root to height of curve of blade; dorsal bar approximately coathanger-shaped, with a pair of submedian anterolateral projections; ventral root of this anchor completely reduced; ventral anchor not fenestrated, 28-53 ^ l° n g from tip of ventral root to height of curve of blade; ventral bar slightly recurved near its lateral ends, 28-68 /a long; marginal hooklets 1 1 - 1 4 V- l° n g- Head trapezoidal, 28-75 ju. wide at base, with well developed head organs. Two pairs of eyespots anterior to pharynx, usually compact. Pharynx 18-48 X 13-40 /x; esophagus short or practically absent; ceca united posteriorly in posterior third of body. Testis oval, comparatively small, 45-125 X 20-50 p., largely at anterior end of posterior third of body or posterior part of middle third. Vas deferens looping around left cecum and forming a seminal vesicle anteriorly. Cirrus 60-128 ¡x in total length, consisting of a bulbous base 11-25 /x wide and a wing-like cirrus proper 27-40 ¡x long, supported by two (long and short) terminally curved, solid, whip-like spicules, of which the longer is usually barbed a little distal to its middle; the wing-like portion may appear like a sail-like membrane, with a small, transversely striated pad at middle; the greater proximal portion of the copulatory organ is surrounded by oblique muscle fibers. Prostatic reservoir subcylindrical to claviform, 9-25 fx wide, situated longitudinally anterodorsal to cirrus, receiving prostatic duct coming from posterior group of prostatic cells lying behind base of cirrus. Prostatic cells divided into two (an anterior and a posterior) groups. Genital pore usually a little out of median line at junction of anterior with middle third of body. Ovary elliptical to oval, 20-93 X 11-35 fr postequatorial or equatorial. The only uterine egg observed, in a specimen from the type host, measured 70 X 35 fn, in somewhat crumpled condition, with rigid posterior filament terminating in a knob 11 /u. wide. Vagina subcylindrical or tubular, 18-46 X 9-23 ix, provided with thick wall of longitudinal muscle fibers, opening ventrally close to right margin of body a little anterior to transverse vitelline duct. In one specimen it was seen opening by an oval aperture 23 ¡x long by n.6 ¡x wide. In the type the vagina appears bulbous, but in the majority of specimens it is a narrow tube surrounded by longitudinal muscle fibers. Vaginal duct narrow, arising terminally from vagina. Seminal

Dactylogyridae

DISCUSSION

62 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

63 HABITAT HOLOTYPE

87

receptacle 11-32¡x long by 11-28 ¡x wide. Vitellaria profusely developed, co-extensive with intestine, may or may not be confluent between ovary and testis. This species is characterized by wing-like cirrus, to which the specific name refers, and by the uvula-like postvaginal lobe. Haliotrema rectangulare n. sp.

FIGURE 6 2

Gills of Pervagor spilosoma; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 3 5 . (Based on 10 whole mounts.) Body elongate, flattened subcylindrical, 0.3-0.45 mm long, 70-100 ¡¡. wide at testicular level. Opisthohaptor rhomboid, 90-130 ¡1 wide at level of lateral projections; dorsal anchor 46-54 ¡x long lineally from tip of dorsal root to height of curve of blade; dorsal bar coathanger-shaped like ventral bar, 30-37 ¡x long; ventral anchor 37-40 ¡x long from tip of ventral root to height of curve of blade; ventral bar 46-56 ¡x long; marginal hooklet 11-12 ¡x long. Head trapezoidal, 40-55 n wide, with well developed head organs. No eyespots. Pharynx oval, 18-23 f- i n diameter; esophagus short; ceca united posterior to testis. Testis oval, 23-46 x 18-35 a t posterior part of middle third of body. Vas deferens looping around left cecum, bending back on itself near tip of cirrus to form inverted claviform seminal vesicle. Cirrus 23-33 A1 lineally, enclosed in muscle sheath, consisting of cylindrical or bell-shaped base 9-12 ¡x wide and a narrower cylindrical shaft bent at right angles about its middle, opening at anterior corner of its truncate apex. Prostatic reservoir midventral, postbifurcal. Prostatic cells divided into two (an anterior and a posterior) groups. Ovary oval, 23-46 X 18-35 equatorial. Vitellaria co-extensive with intestine. Seminal receptacle oval, 11-16 X 7-16 ¡x. Vagina cup-shaped, small, 9 ¡X wide in the type, opening on or close to right margin of body a little posterior to level of base of cirrus. Vaginal duct running straight backward from base of vagina. Around the vaginal pore may be seen a circular outline, but no circumvaginal pouch as seen in Haliotrema pervagoris. This species differs from Haliotrema pervagoris n. sp. from the same host species in its smaller body size, in the cirrus not being spoon-shaped distally and its base not being obliquely truncate, and what is more important, in the absence of a "circumvaginal pouch." The specific name refers to theright-angledcirrus.

Haliotrema scyphovagina n. sp.

FIGURE 6 3

Gills of Chaetodoti miliaris (type host) and C. multicinctus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 136.

88

DESCRIPTION

DISCUSSION

64 HABITAT HOLOTYPE DESCRIPTION

(Based on 16 whole mounts.) Body rather slender, flattened subcylindrical, 0.3-0.6 mm long, up to 50-70 ¡i wide at level of copulatory organ or in ovariotesticular region. Opisthohaptor constricted off from body proper, 15 ja wide at constriction, 65-100 ¡x wide at level of lateral projections; dorsal and ventral anchors inconspicuously fenestrated, 35-50 ¡x long from tip of longer root to height of curve of blade; dorsal bar 40-48 ¡x long, arcuate; ventral bar coathanger-shaped, nearly as long as dorsal bar. Head 20-60 ¡x wide, produced anteriorly into four prominent digitiform lobes, each containing a head organ. Two pairs of eyespots anterior to pharynx. Pharynx oval, 15-23 X 12-28 ¡x, with head glands on each side; esophagus short; ceca distinctly united posterior to testis. Testis elliptical, postequatorial, 37-75 X 20-40 ¡x. Vas deferens swollen at level of anterior end of ovary and swollen again as it turns round the left cecum, bending back on itself anteriorly to form inverted claviform seminal vesicle. Prostatic reservoir small, alongside base of cirrus, receiving at its base the ascending prostatic duct from posterior group of prostatic cells. Prostatic cells in two groups, anterior group mostly around base of prostatic reservoir, posterior group behind base of cirrus. Cirrus 22-38 ¡x a cylindrical shaft long, consisting of an enlarged base 12-13 (6-7 /i wide), from the left side of which a flagellum-like subterminal filament projects and may show out of the genital pore. Genital pore postbifurcal. Ovary 25-50 X 15-25 ¡x, longitudinally elongated, overlapping testis posteriorly. Vagina bowl- or cup-shaped, with wide opening ventral or posteroventral to base of cirrus, with cuticular walls folded in some flattened specimens; vaginal duct arising near margin of vaginal pore, running obliquely backward. Seminal receptacle elliptical, small. This species is characterized by the enormous scyphiform vagina which opens ventrally at the level of the base of cirrus. In this respect it resembles Haliotrema japonense Yamaguti, 1934, but it differs in the structure of the copulatory organ. The specific name refers to the scyphiform vagina.

Haliotrema

serpentidmts

n. sp.

FIGURE

64

Gills of Acanthurus dussumieri; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 137. (Based on four whole mounts.) Body flattened subcylindrical, 0.8-0.86 X 0.1-0.12 mm. Opisthohaptor 115-140 ¡x wide; dorsal anchor 67-73 long from tip of prominent dorsal root to height of curve of blade, with ventral root reduced; dorsal bar 55-63 ¡x long lineally between tips of posterolaterally directed ends; ventral anchor fenestrated, 67-75 from tip of ventral root to height of curve of blade; ventral bar 60-73 fx long, with paired submedian swellings anteriorly; marginal hooklet 12-13 flong. Head trapezoidal, 60-80 ¡x wide, with three pairs of head organs on each side. Two pairs of compact eyespots anterodorsal to pharynx.

Dactylogyridae

DISCUSSION

65 HABITAT HOLOTYPE DESCRIPTION

89

Pharynx 30-35 X 25-30 esophagus short; ceca united posteriorly in anterior part of posterior third of body. Testis elliptical, 100-130 X 50-60 n, postequatorial. Vas deferens looping around left cecum, bending back on itself anteriorly to form a slender seminal vesicle which lies alongside the prostatic reservoir. Copulatory organ consisting of a narrow, tubular, undulating, barbed cirrus proper with stalked, bell-shaped base 17-20 ¡x long by 15-20 ¡x wide and a small, wing-like accessory fold supported by a whip-like spicule which originates from the lateral incision of the stalk of the cirrus. Prostatic reservoir very much elongated, claviform, extending longitudinally along cirrus on its left or dorsal side; prostatic cells strongly developed between cirrus and anterior cecal arch. Genital pore median, shortly postbifurcal. Ovary longitudinally elongated, equatorial, 60-85 X 20-30 ¡i. Vagina elongate pyriform, 40-62 X 15-25 n, weakly muscular, opening on right margin of body at level of base of cirrus; vaginal duct arising a little subterminally from vagina. Seminal receptacle 20-25 X 10-15 /"• ^ narrow canalis receptaculi seminis arising from anterior end of seminal receptacle, reaching to ventral side of left cecum, where it appears to end blindly. Vitellaria co-extensive with intestine. No eggs observed. The present species is characterized by the undulating cirrus which is provided with a whip-like spicule and a wing-like accessory fold and by the presence of a canalis receptaculi seminis. The specific name refers to the serpentine cirrus proper.

Haliotrema sigmoidocirrus n. sp.

FIGURE

65

Gills of Acanthurus mata (type host) and A. dussumieri; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 138. (Based on 21 whole mounts.) Body elongate, tapering posteriorly, 0.8-1.12 mm long, 0.12-0.24 mm wide in ovariotesticular region. Opisthohaptor connected with body proper by a distinct stalk, 116-200 wide at level of lateral projections; marginal hooklets 1 2 - 1 5 l° n g; dorsal anchor fenestrated, 72-88 n long from tip of dorsal root to height of curve of blade, with ventral root almost completely reduced; dorsal bar 62-88 /t long, with a posterior protuberance near each anterolateral^ directed end and a flat median anterior elevation; ventral anchor indistinctly fenestrated, 60-70 11 long from tip of ventral root to height of curve of blade; ventral bar approximately coathanger-shaped, 58-88 long, with paired submedian swellings anteriorly. Head trapezoidal or 4-lobed, 75-100 X 30-39 11. Esophagus short; ceca confluent posteriorly at anterior part of posterior third of body. Testis subglobular to oval, 75-125 X 40-125 ¡x, equatorial or just postequatorial. Vas deferens looping around left cecum, forming inconspicuous inverted claviform seminal vesicle. Copulatory organ 90-150 ¡x long lineally from base to tip, consisting of sigmoid, tubular, flanged cirrus

9o

proper bent at right angles close to its non-sclerotized, bell-shaped base 17-25 ¡X long by 23-30 ¡i wide, and a fine solid, whip-like accessory filament 80-90 ¡X long lineally. This filament has a fine side branch directed toward the cirrus proper proximal to its middle, and terminates in close proximity to tip of cirrus. Prostatic reservoir inverted claviform or retort-shaped, 15-55 f- wide, lying longitudinally to left of distal portion of copulatory organ, with its terminal portion a little swollen and provided with distinct circular muscle fibers just before opening into base of cirrus. Prostatic cells profusely developed in anterior inter- and extra-cecal fields. Genital pore median, shortly postbifurcal.

DISCUSSION

Ovary longitudinally elongated and curved, 50-125 X 25-46 ¡x. Vagina claviform or subcylindrical, 50-140 X 25-57 /*> provided with circular muscle fibers at its opening which lies at the level of the proximal portion of the copulatory organ, comparatively thin-walled elsewhere, extending obliquely backward from its pore to transverse vitelline duct. Vaginal duct arising sideways from near posterior end of vagina, where it turns abruptly inward to run alongside vagina. Seminal receptacle apparently absent. No eggs observed. Vitellaria co-extensive with intestine. This species is characterized by the structure of the copulatory organ. In this respect it resembles Hdliotrema zancli n. sp. more closely than any other members of the genus Haliotrema, but the muscular distal swelling of the prostatic reservoir has not been observed in H. zancli. The detailed structure of the anchors and bars is different in the two species. T h e specific name refers to the shape of the main portion of the cirrus.

66

HABITAT HOLOTYPE DESCRIPTION

Haliotrema spiculare n. sp.

FIGURE 6 6

Gills of Brotula multibarbata; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 139. (Based on 20 whole mounts.) Body elongate, 0.36-0.55 mm long, 0.070.16 mm wide at testicular level. Opisthohaptor constricted off from body proper, 90-115 p wide at level of lateral projections; dorsal anchor 22-25 ¡x long lineally from tip of longer dorsal root to height of curve of blade, with reduced ventral root; dorsal bar 30-40 ¡x long lineally, with prominent sublateral projections; ventral anchor 22-25 f- l ° n g from tip of ventral root to height of curve of blade, with reduced dorsal root; ventral bar coathanger-shaped, 30-40 ¡x long; marginal hooklets 12-13 ¡1 long. Head 40-65 fx wide, with a median notch and a row of head organs along anterolateral margin. Eyespots dissociated. Pharynx globular, 11-25 ¡x in diameter; esophagus very short; ceca united posteriorly behind testis. Testis oval to elliptical, 58-109 X 30-58 ¡x, at junction of middle with posterior third of body. Vas deferens looping around left cecum at level of vaginal duct. N o definite seminal vesicle. Cirrus spicular, up to 50 ¡x long, with bell-shaped base and a very fine, spirally twisted point. Prostatic reservoir small, 15-27 X 5-13 ¡x, to left of base of cirrus, receiving long

Dactylogyridae

DISCUSSION

67 HABITAT

HOLOTYPE DESCRIPTION

91

ascending prostatic duct coming from posterior group of prostatic cells. Genital pore immediately postbifureal, forming a sucker 10-15 /x in diameter. Ovary subglobular, 3 7 - 7 5 X 3 0 - 5 8 p., nearly equatorial. No eggs observed. Vagina fusiform, 3 2 - 5 0 X 7 . 5 - 2 0 p, provided with longitudinal muscle fibers; vaginal duct narrow, arising from posterior end of vagina. Seminal receptacle elongate, overlapping anterior end of ovary. Vitellaria co-extensive with intestine. This species is characterized by the fine spicular cirrus proper and the well defined genital sucker. The specific name refers to the shape of the cirrus proper.

Haliotrema spirale n. sp.

FIGURE 6 7

Gills of Mulloidichthys pfluegeri (type host), M. auriñamma, M. samoensis, Parupeneus pleurostigma and P. chryserydros; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 140. (Based on 34 whole mounts.) Body flattened subcylindrical, constricted at level of vagina, 0 . 6 - 0 . 8 7 X 0 . 1 2 - 0 . 2 2 mm. Opisthohaptor well constricted off from body proper, 0.11 mm wide in the type, with two pairs of non-fenestrated anchors, two dissimilar bars, and several marginal hooklets about 1 0 fi long; dorsal anchor 6 0 - 8 2 ¡x long lineally from tip of dorsal root to height of curve of blade; dorsal bar flexed forward at both ends, 45-61 ¡x from end to end; ventral root of dorsal anchor definitely shorter than dorsal root; ventral anchor 4 5 - 7 5 /A long lineally from tip of ventral root to height of curve of blade; dorsal root broadly rounded and much shorter than ventral root; ventral bar 5 2 - 7 5 /x from end to end, curved in form of a letter V, each arm with a conspicuous subterminal swelling on medial side. Anterior to the anchor apparatus is a pair of small muscle pads, with which are connected the roots of the anchors, and to which are attached very conspicuous muscle bundles; most of the bundle fibers cross over at the level of the constricted part at the base of the opisthohaptor, and the other fibers are continued forward to the same side; the two forwardly directed bundles are split eventually into individual fibers and continued into the subcuticular muscle layer on the ventral side of the body proper. Head 0.08-0.11 mm in diameter, 2-lobed on each side, each lobe studded with distended ducts of head glands lying on both sides of pharynx. Eyespot pigment granules scattered. Mouth opening at level of posterior head lobes. Pharynx globular, 3 0 - 4 0 in diameter; esophagus very short; ceca united posterior to testis. Testis oval to elliptical, 0 . 0 8 - 0 . 1 8 x 0.05-0.13 mm, postequatorial. Vas deferens looping around left cecum, forming an elongate seminal vesicle after bending back on itself anteriorly. Prostatic reservoir claviform, 90140 p. wide, between seminal vesicle and cirrus. Prostatic cells distributed in inter- and extra-cecal fields in zone of terminal genitalia. Cirrus 150-

92

DISCUSSION

68 HABITAT HOLOTYPE DESCRIPTION

190 n long, consisting of anterior spiral portion describing two spirals and provided with wide spiral flange, and a posterior cylindrical portion 80H2 ¡i long. The latter portion is enclosed throughout in a sheath of spiral muscle fibers, its greater proximal portion in turn is enclosed in a bulb of longitudinal muscle fibers. Genital pore median, just postbifurcal. Ovary elongate, oblique, equatorial, 46-95 X 28-82 /i; seminal receptacle elongate, overlapping ovary. Eggs oval, 50-80 n long, 44-60 ¡x wide, with posterior end produced into a terminally knobbed process about 60 ¡x long. Vagina bulbous, 23-46 ¡x wide, with cuticularized lumen, opening on right margin of body, situated transversely or a little obliquely behind base of copulatory organ, with its base produced in form of a blunt cone 15-25 /x long and surrounded by lamellar muscle fibers; vaginal duct arising from tip of this cone, turning back on itself dorsal to vagina. Vitellaria coextensive with intestine. This species resembles Haliotrema minutospirale n. sp. from the same host species in the general anatomy of the genitalia, but it differs distinctly in the size of the copulatory organ and in the muscular coat of its basal portion. In H. minutospirale the cylindrical basal portion of the cirrus is provided with a sheath of circular muscle fibers instead of diagonal fibers and is devoid of the outer bulb of longitudinal muscle fibres which was observed in the present species.

Haliotrema tubulovagina n. sp.

FIGURE 6 8

Gills of Zanclus canescens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 141. (Based on 32 whole mounts.) Body fusiform to subcylindrical, 0.45-0.78 mm in length, 0.08-0.2 mm in maximum width in testicular region. Opisthohaptor 104-175 wide, not well constricted off from body proper; dorsal anchor fenestrated, 37-58 ¡x long lineally from tip of prominent dorsal root to height of curve of blade, with ventral root very much reduced; dorsal bar almost straight, 47-65 ¡x long; ventral anchor fenestrated, 35-58 ¡x long lineally from tip of ventral root to height of curve of blade, with its dorsal root not so much reduced as ventral root of dorsal anchor; ventral bar arcuate, 47-63 ¡x long lineally from end to end; 14 marginal hooklets 12-13 long- Head trapezoidal, 50-112 ¡x wide, with three head organs on each side. Two pairs of compact eyespots anterior to pharynx. Pharynx globular, 18-33 x 35 ceca united posteriorly in anterior half of posterior third of body. Testis round or oval, 51-125 X 30-110 ¡x, postequatorial or equatorial. Vas deferens swollen and sinuous after looping around left cecum, forming rather narrow seminal vesicle. Cirrus tubular, arched, turning back on itself near its enlarged base, 34-90 ¡x lineally from base to tip which is recurved to open ventrally. Prostatic reservoir claviform, lying longitudinally to left of cirrus. Genital pore immediately postbifurcal.

Dactylogyiidae

DISCUSSION

69 HABITAT HOLOTYPE DESCRIPTION

93

Ovary subglobular, immediately pretesticular, 2 3 - 7 5 X 4 1 - 7 0 ¡x. No eggs observed. Vagina tubular, opening on right margin of body a little behind base of cirrus; vaginal duct as direct continuation of vagina. Seminal receptacle oval, 12 ¡x in diameter in the type. Vitellaria co-extensive with intestine. This species resembles Haliotrema Bexicirrus n. sp. very closely, especially in the structure of the cirrus, but differs from it in the shape of the haptoral anchors and in the vagina being tubular. The specific name refers to this latter feature.

Haliotrema

zancli n. sp.

FIGURE 6 9

Gills of Zancltis canescens (type host), Acanthurus dussumieri, A. olivaceus, A. mata and Ctenochaetus strigosus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 4 2 . (Based on 2 0 whole mounts.) Body elongate, tapering anteriorly, 0 . 4 5 0 . 7 2 mm long, up to 5 0 - 1 1 0 p wide in testicular region. Opisthohaptor 65-125 ¡x wide, well constricted off from body proper, with two pairs of similar, fenestrated anchors, two dissimilar bars, and marginal hooklets 10-15 ¡X long. Dorsal anchor 35-55 /x long lineally from tip of dorsal root to height of curve of blade; its ventral root moderately reduced; dorsal bar flattened M-shape, 4 0 - 5 5 ¡x from end to end; ventral anchor similar in size and shape to dorsal anchor; ventral bar 4 0 - 6 0 ¡x from end to end, with irregular outline. Head trapezoidal, 5 0 - 9 0 ¡x wide, usually 2-lobed on each side, with head organs laterally. Two pairs of eyespots very conspicuous; anterior pair prepharyngeal, posterior pair dorsal to pharynx. Pharynx barrel-shaped, 20-30 ¡x in diameter; esophagus 38 ¡x long in the type, ceca united posterior to testis. Testis ovoid, 7 5 - 1 5 0 X 6 0 - 9 0 ¡x, situated at junction of middle with posterior third of body, separated from ovary by vitellaria. Vas deferens comparatively wide, looping around left cecum, recurrent anteriorly to form inverted claviform seminal vesicle about 10 ¡x wide. Prostatic reservoir claviform to fusiform, about 9 ¡x wide, alongside seminal vesicle. Prostatic cells large, well developed in anterior intercecal field. Copulatory organ consisting of bipartite enlarged base, a sigmoid tubular cirrus, and a flanged, whip-like, accessory prong terminating in a curved point. This prong arising along with the cirrus proper from the apex of the common base, provided basally with a cuticular fold, the anterior end of which appears to terminate in a sharp, pointed filament. Genital pore median, shortly postbifurcal. Ovary usually oval, 3 2 - 5 5 X 2 0 - 6 0 ¡x, separated from testis by transverse band of vitelline follicles. Vagina pyriform, 3 0 - 6 0 X 1 7 - 2 8 ¡x, opening on right margin of body at level of base of copulatory organ by a funnelshaped depression, giving rise terminally to a narrow vaginal duct. Seminal receptacle small, anterodorsal to ovary. No mature eggs observed. Vitel-

94

DISCUSSION

laria co-extensive with intestine, confluent anteriorly and posteriorly as well as between ovary and testis. This species resembles Haliotrema acanthuri n. sp. in general structure of the genitalia, but it differs fundamentally in the copulatory organ being more complex and in the vaginal duct arising from the base of the vagina instead of sideways.

KEY TO SPECIES OF

Haliotrema FROM HAWAIIAN FISHES 1

2 3

4

5 6

7

8

9 1

Postvaginal marginal lobe present; cirrus wing-like distally: H. pterophallus Postvaginal marginal lobe absent; cirrus otherwise: 2 Circumvaginal pouch present: 3 Circumvaginal pouch absent: 4 Circumvaginal pouch large; cirrus right-angled, scoop-shaped distally, with obliquely truncated base: H. pervagoris Circumvaginal pouch small; cirrus not scoop-shaped distally, distinctly two-segmented: H. bisegmentatum Cirrus cheliform; genital pore with strong sphincter: H. chelicirrus Cirrus palmate distally, with its base supported by a pair of sclerotized pieces; vagina muscular: H. palmatum Cirrus spicular or tubular, long or short, with or without accessory piece: 5 Genital pore with sucker-like structure; cirrus spicular: H. spiculare Genital pore without sucker-like structure: 6 Prostatic reservoir and seminal vesicle double; vagina with sclerotized bulb; canalis receptaculi seminis very long, reaching to level of testis: H. epinepheli Prostatic reservoir single: 7 Vaginal duct convoluted; prostatic reservoir directed backward from base of cirrus; cirrus spicular, coiled: H. annulocirrus Vaginal duct not convoluted; prostatic reservoir directed forward from base of cirrus: 8 Vagina scyphiform; cirrus two-segmented, with accessory spicule: H. scyphovagina Vagina otherwise: 9 Vaginal duct arising subterminally or farther away from base of vagina: 10 Vaginal duct arising terminally from base of vagina: 12

After completion of this monograph, Mizelle, J. D. and Price, C . E . ( 1 9 6 4 ) published their studies of monogenetic trematodes, Part 25: six new species of Ancyrocephalinae from the gills of Z a n c l u s canescens (Linn.) with a key to the genera of Ancyrocephalinae in the Journal of Parasitology 5 0 ( 1 ) 1 8 1 - 8 9 . Five of the species (Hamatopeduncularia heraldi, Parahaliotrema parahaliotrema, Parahaliotrema dempsteri, Pseudohaliotrema brevis, and Pseudohaliotrema zanclus), all from the Southwest Pacific, resemble our new Hawaiian species of Haliotrema (Haliotrema tubulovagina, H. canescens, H. zancli, H. angulare, and H. ftexicirrus respectively) so closely that the similar species may be identical. Unfortunately Mizelle and Price neither mentioned nor illustrated the details of the internal anatomy of their new species, in particular the structure and position of the prostatic reservoirs and the structure of the vagina and vaginal duct. These characters are of vital importance in discriminating related Haliotrema species. Being unable to compare their species with ours in these respects, I prefer to leave our new species as they are described until we are more fully informed on the internal anatomy of the Southwest Pacific species.

Dactylogyridae

10

95

Canalis receptaculi seminis present; cirrus tubular, serpentine, with accessory prong arising from lateral incision of its basal stalk: H. serpenticirrns Canalis receptaculi seminis absent: 11 11 Cirrus reflexed near enlarged base, C-shaped elsewhere; vagina not tubular; vaginal duct zigzag: H. flexicirrus Cirrus with muscle sheath around proximal portion and spiral fold on distal portion; vaginal duct arising near vaginal pore: a) Ventral haptoral bar bifid laterally: H. bodiani b) Ventral haptoral bar not bifid laterally: H. priacanthi Cirrus enclosed in sheath of longitudinal muscle fibers for its greater proximal part, right-angled near its claw-like point, without accessory prong; vagina filled with sperm at base: H. angulocirrus Cirrus sigmoid, tubular, bent at right angles near its bell-shaped base, with whip-like accessory prong; efferent duct of prostatic reservoir swollen and muscular: H. sigmoidocinus Cirrus hook-shaped, with wide annular base and short slender accessory spine near its enlarged proximal end: H. angulare Cirrus consisting of bell-shaped base and short, cylindrical shaft, from which arise a spicular cirrus proper and a solid shorter accessory prong: H. acanthuri 12 Cirrus reflexed near enlarged base, C-shaped elsewhere; vagina tubular; vaginal duct straight: H. tubulovagina Cirrus cylindrical proximally, spiral distally, without accessory piece; vagina bottle-shaped, giving off vaginal duct from its basal knob-like projection: a) Proximal portion of cirrus enclosed in bulb of longitudinal muscles; cirrus 150-190 v long: H. spirale b) Proximal portion of cirrus not enclosed in bulb of longitudinal muscles; cirrus 70-105 M- long: H. minutospirale Cirrus dagger-shaped, with its blade ornamented with spiral fold supported by two curved filamentous spicules and its basal handle provided with very thick inner coat of circular muscles; vagina tubular: H. lactoriae Cirrus otherwise a) Vagina tubular: 13 b) Vagina funnel-or cup-shaped: 15 c) Vagina more or less bulbous (subcylindrical, pyriform, or retort-shaped, etc.): 17 13 Cirrus very narrow, tubular, flanged, with bell-shaped base and short, curved, slender, accessory spine: H. amanses 14 Cirrus two-segmented, curved at nearly right angles distally: 14 Cirrus devoid of muscle sheath; uterus showing finely granulated epithelia: H. centropygis Cirrus with oblique muscle fibers distal to sheath of circular muscle fibers enclosing proximal portion and a spicular accessory hook: H. chromidis Cirrus enclosed in muscle sheath, without spicular accessory hook: H. rectangulare 15 Cirrus whip-like, with bell-shaped base enclosed in sheath of circular muscles and very fine accessory filament: H. flagellatum Cirrus with a solid spicule arising from point where cirrus starts its looping; dorsal haptoral bar bifid laterally: H. bifurcocirrus Cirrus two-segmented; distal segment curved, without muscle sheath; posterior group of prostatic cells present: 16 16 Cirrus scoop-shaped distally, without apical piece; dorsal haptoral

96

bar with paired submedian projections: H. Cirrus with spicular apical piece; dorsal haptoral bar without paired submedian projections: H. 17 Cirrus with accessory branch or prong and bell-shaped base: Cirrus tubular, more or less undulating, with sclerotized basal ring, without accessory branch; vagina with very weak longitudinal muscles: H. Cirrus tubular, rather short, curved, with two-lobed base, without accessory piece; vagina with very thick wall of circular muscles:

caesiopercae

H.

brotvlae

18 Cirrus narrow, tubular, sigmoid, with whip-like accessory prong and two-segmented base: Cirrus with accessory branch arising from point where cirrus shaft appears distorted: 19 Prostatic reservoir constricted near middle: Prostatic reservoir not constricted: H. 20 Haptoral anchors and bars unusually large: H. Haptoral anchors and bars of usual size: H.

70 HABITAT HOLOTYPE DESCRIPTION

Cleithrarticus

bulbovagina

n. sp.

microphallus

18 curvicirrus

H.

zancli

19 20 ctenochaeti macracantha canescens

FIGURE 7 0

Gills of Acanthurus dussumieri; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 4 3 . (Based on six whole mounts.) Body almost uniformly wide, 1 . 0 - 1 . 5 6 X 0 . 1 1 - 0 . 1 8 mm. Opisthohaptor not clearly constricted off from body proper, with two pairs of dissimilar anchors, two bars articulating with each other, and five pairs of marginal hooklets 15 ¡X long; dorsal anchor non-fenestrated, about 75 ¡x long lineally from tip of dorsal root to height of curve of blade; ventral root of this anchor greatly reduced; dorsal bar stout, articulating with dorsal root of dorsal anchor, 5 2 - 6 0 ¡x lineally from end to end, with anteromedian protuberance; ventral anchor fenestrated, 6 0 - 6 3 P l° n g lineally from tip of ventral root to height of curve of blade; dorsal root of ventral anchor rounded; ventral bar 5 5 - 6 0 /i long, with its median portion provided dorsally with two knobs which lie close together, each knob being produced forward and surrounded by muscle fibers. Head 7 0 - 1 0 0 ¡x wide, with two pairs of inconspicuous head lobes, each of which bears three head gland ducts; head glands extending from beside pharynx to level of intestinal bifurcation. Two pairs of eyespots present. Pharynx bulbous, 5 0 - 7 0 X 4 0 - 4 5 /x; esophagus 1 0 - 7 5 ¡x long; ceca confluent posteriorly. Testis elliptical, 1 2 5 - 1 7 5 x 5 0 - 1 0 0 ¡x, postequatorial. Vas deferens arising from anterior end of testis, passing by left side of ovary, looping around left cecum, forming seminal vesicle anteriorly. Copulatory organ complex, with bell-shaped base, a recurved tubular cirrus with narrow flange, and a sigmoid, sclerotized, accessory piece arising from common base with cirrus. This accessory piece is provided near the middle with a small, hook-shaped barb. The basal portion of the copulatory organ including

Dactylogyridae

DISCUSSION

71 HABITAT DESCRIPTION

97

the proximal curve of the accessory rod is surrounded by muscle fibers. Prostatic reservoir well provided with diagonal muscle fibers, divided into two elongate portions, the connecting bridge of which receives the ascending duct from the posterior group of prostatic cells. Prostatic cells divided into two (an anterior and a posterior) groups; anterior cells confined to anterior intercecal field, but the posterior cells extend not only in the intercecal field but also in the extracecal field as far backward as level of the seminal receptacle. Genital pore median, shortly postbifurcal. Ovary elliptical, 7 5 - 1 7 5 X 3 0 - 5 0 pre-equatorial or equatorial. Uterus containing one egg at a time. Eggs irregularly oval, 6 2 - 8 0 X 40-55 ¡x, with short polar filament swollen at tip. Vitellaria extending along whole length of ceca. Vagina bulbous, 2 0 - 3 0 ¡1. wide, opening ventral to right cecum at level of base of copulatory organ. Vaginal duct narrow, originating at base of vagina. Seminal receptacle oval. This species differs from Cleithrarticus cleithrarticus Mizelle, 1 9 6 3 in the structure of the cirrus and vagina and in the absence of paired canalis receptaculi seminis. The specific name refers to the bulbous vagina.

Cleithrarticus cleithrarticus Mizelle,

1963

FIGURE 7 1

Gills of Acaxithurus olivaceus, A. dussumieri and A. mata; Hawaii. (Based on 30 whole mounts.) Body flattened subcylindrical to fusiform, 1 . 0 - 2 . 1 X 0 . 1 4 - 0 . 4 4 mm, widest in ovariotesticular zone, markedly tapering posteriorly to form a haptoral peduncle which is more or less attenuated just anterior to opisthohaptor. In the relaxed specimens as well as in those mounted in lactophenolglycerine-jelly this peduncle is only 30 P wide at the narrowest part. Opisthohaptor indistinctly 2-lobed, with two pairs of distinctly fenestrated anchors, two bars articulating with each other, and several pairs of marginal hooklets 12-15 long; anterodorsal bar 3 3 - 8 0 p. in transverse diameter, articulating with head of posteroventral bar, with a pair of minute, submedian, nodular projections on anterodorsal surface; posteroventral bar with small anterior lateral thickenings and produced backward into a pair of digitiform processes, measuring 2 2 - 2 8 from anterolateral thickening to tip of posterior digitiform process, and 2 0 - 2 8 ¡n wide at level of anterior thickenings and 4 0 - 7 0 ¡x. wide at level of tips of posterior processes; dorsal anchor 5 0 - 8 0 ¡i from tip of dorsal root to height of curve of blade, with sleeve-like expansion for ventral root to articulate with wing-like lateral arms of anterodorsal bar; ventral anchor 5 2 - 7 0 ¡x from tip of ventral root to height of curve of blade, articulating with digitiform posterior processes of posteroventral bar. Head with a minute median notch and three or more head organs along each anterolateral margin; their glands extending on each side of pharynx and esophagus. Two pairs of eyespots present. Pharynx 3 0 - 7 5 X 3 2 - 6 3 yu.; esophagus short, up to 2 5 ¡j. long when extended; ceca united posteriorly.

98

Testis oval to elliptical, just postequatorial, 7 5 - 1 7 5 X 5 0 - 1 5 0 ¡x. Vas deferens distended with sperm between posterior portion of ovary and left cecum, looping around left cecum in a loose spiral, bending back on itself anteriorly to form fusiform seminal vesicle which is intercalated between two portions of prostatic reservoir. Copulatory organ consisting of a long tubular cirrus proper and a narrow, solid, hook-like prong arising from base of cirrus proper; cirrus proper U-shaped proximally but recurrent distally; it bends back on itself at a distance of 1 0 2 - 1 4 0 ¡x from height of basal curvature and terminates in a small sleeve-like expansion tipped with a flute-like structure. At the base of the cirrus proper is a sclerotized U-shaped basal piece which is somewhat corrugated on the surface and 4 5 - 5 5 /x long lineally. Genital pore apparently opening at tip of cirrus. Prostatic reservoir bipartite, provided with diagonal muscle fibers; the two portions are connected by a narrow, non-muscular bridge; anterior portion fusiform to subcylindrical, 5 0 - 1 2 5 X 1 8 - 4 0 ¡i, containing granules, may overlap posterior portion, latter 7 5 - 1 3 0 /t long by 2 0 - 2 5 P wide, containing clear, less granular secretion. The distal end of efferent duct from this posterior portion and the ejaculatory duct are enclosed in a sheath of circular and longitudinal muscle fibers just before emptying into the base of the cirrus proper. Prostatic cells large, extending in inter- and extra-cecal fields from level of intestinal bifurcation down to level of base of vagina. The duct from the posterior prostatic cells runs toward the posterior end of the anterior portion of the prostatic reservoir, where it joins the connecting bridge mentioned above.

DISCUSSION

72 HABITAT HOLOTYPE DESCRIPTION

Ovary elongate, median, pre-equatorial, pretesticular, 7 5 - 2 1 3 X 3 0 - 6 7 ¡x. Seminal receptacle small, 2 0 - 5 0 X 1 2 - 2 3 p, giving off on each side a narrow transverse canalis receptaculi seminis ending blindly. Vitellaria co-extensive with intestine, confluent immediately behind testis. Vagina subcylindrical to claviform, oblique, opening on right margin of body at level of copulatory organ, 1 0 0 - 1 7 5 X 2 0 - 6 3 vaginal duct arising from swollen posterior end of vagina, provided with circular muscles like a sphincter a little before opening into seminal receptacle. Mizelle stated that there are two prostatic reservoirs, one containing granular fluid and the other hyaline fluid, but actually they are continuous by means of a narrow duct. This character, as well as the articulating haptoral bars, certainly justifies the creation of a new genus, for which Mizelle rightly proposed the name Cleithrarticus.

Pseudancyrocephalus

kala n. g., n. sp.

FIGURE 7 2

Gills of Naso brevirostris and N. hexacanthus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 4 4 . (Based on 1 8 whole mounts.) Body rather fusiform, widened at preequatorial level when flattened, 1 . 0 - 1 . 8 X 0 . 2 - 0 . 4 4 mm. Opisthohaptor not

Dactylogyridae

99

well marked off from body proper, 100-210 ¡x wide. Dorsal anchor 107130 ¡x long lineally from tip of stout, longitudinally striated ventral root to height of curve of blade; dorsal root of this anchor reduced to a small rod; dorsal bar slender, slightly swollen at each end, 30-38 ¡x long; ventral anchor with stout longitudinally striated, bifurcate root, 105-150 ¡x lineally from tip of ventral root to height of curve of blade; dorsal root of this anchor a little shorter than ventral root; ventral bar somewhat dumbbell-shaped, 17-23 ¡x long. Head end blunt or somewhat truncate, with head organs laterally. Eyespots dissociated in pharyngeal region. Pharynx muscular, 60-100 X 47-75 ¡x; esophagus very short; ceca not united posteriorly. Testis spherical to oval, 150-280 X 100-260 ¡x, equatorial or postequatorial. Vas deferens arising from middorsal surface of testis, running forward and winding medial to left cecum, bending back on itself anteriorly to form seminal vesicle. Seminal vesicle fusiform, with thick wall of diagonal muscle fibers, 30-75 X 12-30 ¡x, lying longitudinally behind intestinal bifurcation. Copulatory organ complex, consisting of a cirrus proper which is tubular basally but flared distally into a wing-like, transversely striated expansion and an accessory piece which is rod-like, slightly arcuate, and distinctly sclerotized throughout, with its anterior point a little recurved. This accessory piece has an irregular basal lobe and supports the cirrus in its concavity. Genital pore midventral, postbifurcal. There are two prostatic reservoirs provided with fine oblique muscle fibers; left one longer, 50-100 X 10-20 ¡x, lying alongside seminal vesicle; right one 25-40 X 12-25 situated a little obliquely between right cecum and copulatory organ. Prostatic cells divided into three groups; left group empties into the left prostatic reservoir, whereas the other two right groups empty into the right prostatic reservoir. It is interesting to note that both afferent and efferent prostatic ducts enter the prostatic reservoirs at their posterior end.

DISCUSSION

Ovary irregularly oval, 75-200 X 25-170 ¡x, pre-equatorial. Seminal receptacle oval, 30 X 22.5 ¡x in the type, overlapping transverse vitelline duct, giving rise to canalis receptaculi seminis on its right side. This canal can be traced down to the right side of the ovary, but it is not certain whether it ends blindly or not. Vagina tubular or bulbous, with thin wall of fine circular and longitudinal muscle fibers, opening ventrally medial to right cecum at level of base of copulatory organ; vaginal duct muscular, long, as direct continuation of vagina. Uterus midventral, containing filamented egg. Vitellaria co-extensive with intestine. The Hawaiian ancyrocephaline species provided with longitudinally striated anchors possess, without exception, two prostatic reservoirs, with the seminal vesicle in between, and a canalis receptaculi seminis except in Pseudancyrocephalus longispicularis. These characters are sufficient to justify the creation of a new genus, for which the name Pseudancyrocephalus is proposed with the following diagnosis.

LOO

Pseudancyrocephalus n. g. GENERIC DIAGNOSIS

TYPE SPECIES OTHER SPECIES

Dactylogyridae, Ancyrocephalinae. Opisthohaptor with two pairs of anchors, the roots of which are subequal or quite unequal and longitudinally striated, two dissimilar bars, and several pairs of marginal hooklets. Eyespots usually present. Pharynx muscular; ceca terminating separately. Testis entire. Vas deferens running forward in intercecal field, never looping around cecum. Seminal vesicle muscular or not, between two prostatic reservoirs. Prostatic reservoirs usually provided with spiral muscle fibers. Cirrus tubular, simple or complex, with accessory piece. Genital pore postbifurcal. Ovary rather irregular in shape, directly pretesticular. Vagina usually tubular, opening close to right margin of body. Seminal receptacle with or without canalis receptaculi seminis. Vitellaria coextensive with intestine. Parasites of marine teleosts, particularly of the genus Naso. P. kola n. sp. P. duplicatus n. sp. P. lotigicirrus n. sp. P. longispicularis n. sp. P. nasonis n. sp.

73 HABITAT HOLOTYPE DESCRIPTION

Pseudancyrocephalus

duplicatus n. sp.

FIGURE 7 3

Gills of Naso unicornis; Hawaii. U.S. Nat Mus. Helm. Coll., S.Y. No. 145. (Based on 15 whole mounts.) Body fusiform, 1.5-2.1 mm long, up to 0 . 2 3 - 0 . 4 5 mm wide in midregion. Opisthohaptor with short broad stalk, 0.15 mm wide in the type 1.55 mm long, with two pairs of anchors, the roots of which are longitudinally striated. Dorsal anchor 1 3 7 - 1 7 0 long from tip of longer dorsal root to tip of blade, with ventral root a little shorter than dorsal root; dorsal bar plump, 2 5 - 3 0 ¡x long; ventral anchor 1 2 0 - 1 5 8 p long from tip of dorsal root to tip of blade; ventral root of this anchor reduced to a stumpy rod; ventral bar dumbell-shaped, 4 5 - 5 0 ¡x long; marginal hooklets about 1 2 . 5 ¡x long. Head rounded conical, 7 0 - 1 2 0 ¡x wide at base which is more or less distinctly delimited from the body, with few head organs on each side. No compact eyespots. Pharynx (Soi l 5 X 5 2 - 9 3 (i; esophagus short, up to 1 1 5 ¡i long when extended; ceca terminating separately, though close together, near posterior extremity. Testis rounded, 1 7 5 - 2 2 5 X 1 1 2 - 2 1 3 postequatorial. Vas deferens winding forward medial to left cecum and lateral to copulatory organ, bending back on itself a little behind intestinal bifurcation to form inverted retortshaped seminal vesicle 18-45 f- wide. Copulatory organ consisting of a C-shaped, tubular cirrus about 1 5 0 - 2 0 0 ¡x long and a solid accessory piece. Cirrus proper surrounded at its rounded base by muscle bulb, whose fibers extend longitudinally along the proximal portion of the cirrus; its

Dactylogyridae

101

distal portion terminates in a pedicellaria-like point. Accessory piece about 125 ¡x long, C-shaped like cirrus and closely parallel to it, with its curved base in contact with rounded base of cirrus, terminating in a recurved barb. There are two prostatic complexes; right prostatic reservoir saccular, 32-50 ¡x wide, dextro-anterior to base of cirrus; left reservoir containing coarser secretory granules, longitudinally elongated, 70-115 X 12-43 /*> situated longitudinally between left cecum and copulatory organ. The prostatic cells on this side contain coarse granules and lie mostly posterior to the reservoir. The duct from this reservoir traverses the copulatory organ dorsally in form of an inverted letter V before opening into the base of the cirrus. Genital pore shortly postbifurcal. Ovary subglobular, 100-150 X 50-140 ¡x, equatorial. No eggs observed. Vagina tubular, non-muscular, curved before opening submarginally at level of posterior end of copulatory organ; vaginal duct may be winding in some specimens, partly sclerotized and surrounded by circular muscle fibers in the type. Seminal receptacle small, 20-40 X 15-30 jx; a straight narrow canalis receptaculi seminis arising from this seminal receptacle runs backward obliquely and apparently terminates blindly dorsolateral to ovary. Vitellaria co-extensive with intestine, confluent in posttesticular area. DISCUSSION

74 HABITAT HOLOTYPE DESCRIPTION

This species resembles Pseudancyrocephalus kala from Naso brevirostris in general anatomy, especially in possessing a solid, curved accessory piece and a canalis receptaculi seminis, and in the structure of the haptoral anchors, but it differs distinctly in the structure of the cirrus. The specific name refers to the parallel copulatory pieces.

Pseudancyrocephalus

longicirrus

n. sp.

FIGURE 74

Gills of Naso brevirostris and N. hexacanthus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 146. (Based on seven whole mounts.) Body fusiform, 1.25-1.95 X 0.28-0.5 mm. Opisthohaptor well constricted off from body, sometimes projecting laterally in form of a sleeve, with 14 marginal hooklets. Dorsal anchor with two long, longitudinally striated, subequal roots, 112.5-137.5 ¡x long lineally from tip of dorsal root to height of curve of blade; dorsal bar thickened at middle as well as at each end, 22-25 P fr°m e n d to end; ventral anchor with a rudimentary ventral root and a strong, longitudinally striated, dorsal root, 100-125 ¡1 long lineally from tip of dorsal root to height of curve of blade; ventral bar dumbell-shaped, 37-45 p long. Head end trapezoidal, about 30 ¡x wide in the type, with head organs at anterolateral corners; gland cells massed on each side of pharynx and also at postpharyngeal level. There are, in addition, two pairs of isolated gland cells, one pair in front of pharynx and the other close to the sides of pharynx. Eyespots dissociated dorsal to pharynx and vicinity. Pharynx cylindrical, with slight constriction behind middle, 37-75 X 30-50 /x; esophagus short,

102

up to 50 /* long; ceca extending to near opisthohaptor, not united posteriorly. Testis rounded, 125-175 X 125-150 p, at posterior part of middle third of body. Vas deferens arising from middorsal surface of testis, running forward dorsal to transverse vitelline duct and then winding among left prostatic cells and alongside cirrus, bending back on itself anteriorly to form seminal vesicle which is 20-38 ¡x wide and lies on the left of the median line in front of the genital pore. Cirrus narrow, tubular, 170-210 ¡1 long, turning backward near its base and descending to near level of posterior end of vagina, where it turns back on itself again and reaches the genital pore. At this point it terminates in a minute nodular swelling; accessory pieces 87-118 ¡x long, well sclerotized, arising from common base with cirrus, directed straight forward close parallel to each other, each terminating in bifid claw about 35 ¡x behind genital pore in the type. Large, saccular prostatic reservoir 62-85 ¡x in diameter, situated on right of terminal portion of copulatory organ, receiving near its anterior end two collecting prostatic ducts coming from behind. There is another elongate, somewhat muscular, prostatic reservoir alongside the ascending terminal portion of the vas deferens, surrounded by the prostatic cells of its own. There are, therefore, an anterior and two posterior groups of prostatic cells, as shown in the figure. Genital pore median, at tip of cirrus some distance behind intestinal bifurcation.

DISCUSSION

75 HABITAT

HOLOTYPE DESCRIPTION

Ovary immediately pretesticular, just behind equator, 50-125 X 100150 p. Canalis receptaculi seminis arising sideways from seminal receptacle, passing backward on dorsal surface of ovary, near the right margin of which it appears to terminate blindly. This canal contains sperm proximally, so it may correspond to the Laurer's canal in the digenetic trematodes. Seminal receptacle oval, 37 X 25 ¡x. Vagina cylindrical, 200-250 X 32-50 p., provided with circular and longitudinal muscle fibers, tapering proximally, curved just before opening outside close to right margin of body at level of right larger prostatic reservoir. Vaginal duct narrow, as direct continuation of vagina. Egg subglobular, 87—95 X 67-85 ¡x in mounted specimens, with moniliform polar filament 87-125 ¡x long. Vitellaria co-extensive with intestine, confluent in posttesticular region. This species is characterized by the long recurrent cirrus and the long vagina and by the presence of a canalis receptaculi seminis.

Pseudancyrocephalus longispicularis n. sp.

FIGURE 75

Gills of Naso brevirostris; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 147. (Based on 20 whole mounts.) Body subcylindrical flattened, 0.9-1.42 X 0.16-0.26 mm. Opisthohaptor not well constricted off from body proper; dorsal anchor longitudinally striated, 90-118 ¡x long from tip of ventral root to height of curve of blade; ventral root slightly shorter than dorsal

Dactylogyridae

103

root; dorsal bar 2 0 - 2 8 ¡x long; ventral anchor 8 7 - 1 3 3 ¡x long from tip of stout, longitudinally striated, dorsal root to height of curve of blade; ventral root of this anchor very much reduced; ventral bar 2 3 - 4 0 ¡x long. Head blunt-pointed, 7 5 - 1 2 5 fi wide, with well developed head organs; head lobes may project prominently in horn-like projections. Eyespots dissociated in prepharyngeal region. Pharynx elongate, 4 5 - 7 0 X 3 0 - 4 5 N; esophagus very short; ceca terminating separately at about middle of posterior third of body. Testis round to oval, 6 2 - 1 5 0 X 3 5 - 1 0 0 jx, at posterior end of middle third of body. Vas deferens inflated and winding medial to left cecum, bending back on itself anteriorly to form inverted claviform seminal vesicle. Cirrus spicular, 2 7 5 - 3 8 0 fi long, looped once or twice, bulbous at base, enclosed proximally in muscle sheath of longitudinal fibers. To the base of the cirrus is attached a poorly sclerotized plate with which the accessory piece is articulated. Accessory piece somewhat spirally twisted, very complex in structure as shown in the figure, 6 2 - 9 5 ¡x long, probably serving as gubernaculum for the cirrus, with horn-like point, through the inner groove of which passes the cirrus. Around the accessory piece are mostly radiating, partly lamellar, muscle fibers, probably functioning as fixer of the piece. A small banana-shaped prostatic reservoir receiving ascending duct from right prostatic cells lies dextral to base of cirrus. Another prostatic reservoir, similar in shape but enclosed in a thick sheath of longitudinal muscle fibers, lies longitudinally on the left side of the distal end of the accessory copulatory organ, receiving the collecting prostatic duct from the left group of prostatic cells at its posterior end, where its own efferent duct is given off. Genital pore a little postbifurcal.

DISCUSSION

76 HABITAT HOLOTYPE DESCRIPTION

Ovary somewhat irregular in outline, 5 0 - 1 2 5 X 2 5 - 8 0 ¡x, slightly overlapping testis posteriorly. Vagina tubular, curved, 2 7 - 4 5 P- l°n6> enclosed in a muscle sheath of longitudinal fibers, opening on ventrodextral margin of body at level of base of cirrus; vaginal duct long, narrow, convoluted before leading into a T-shaped sclerotized structure, the apex of which is swollen into a small dome surrounded by homogeneous semicircular tissue. Seminal receptacle lies on the left side of the point where the vaginal duct joins the germiduct. No eggs observed. Vitellaria co-extensive with intestine. This species is characterized by the long, convoluted vaginal duct provided with a peculiar structure and by the long, spicular cirrus, to which the specific name refers.

Pseudancyrocephalus nasonis n. sp.

FIGURE 7 6

Gills of Naso brevirostris (local name "kala"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 4 8 . (Based on 3 3 whole mounts.) Body 0.39-0.85 mm long, tapering anteriorly, up to 0 . 1 - 0 . 3 2 mm wide at about two-thirds of body length from head end.

104

Opisthohaptor not well marked off from body proper, with two pairs of longitudinally striated anchors, two bars, and few marginal hooklets 12 long; dorsal anchor 100-132 ¡x long from tip of very stout ventral root to height of curve of slender blade; dorsal root of this anchor nearly half as long as ventral root and more than half as wide; dorsal bar 25-35 l°ng; ventral anchor 105-123 ¡x from blunt tip of dorsal root to height of curve of slender blade; ventral root of this anchor rudimentary; ventral bar recurved at both ends, 40-50 ¡1 long. Head trapezoidal, 50-120 ¡x wide, with four or five head organs on each side; head glands massed together on each side of pharynx. Eyespots dissociated in dorsal neck region. Pharynx 25-58 X 15-48 ¡x; esophagus practically absent; ceca separate posteriorly. Testis round, 30-125 X 25-88 ¡x, at junction of middle with posterior third of body. V a s deferens winding forward medial to left cecum, without looping around it, bending back on itself anteriorly to form inverted claviform seminal vesicle well provided with diagonal muscle fibers. Copulatory organ consisting of a narrow tubular cirrus with truncated point and two accessory pieces; one of the accessory pieces has a thick sigmoid base and terminates in a recurved point, while the other shows a curved, weakly sclerotized swelling basally and takes a course similar to the cirrus proper. There are two prostatic reservoirs; the anterior is longitudinally elongated and lies immediately in front of the cirrus; the posterior is saccular and lies anterodextral to the base of the cirrus. Prostatic cells in two groups; right group for anterior reservoir, posterior group for posterior reservoir. Genital pore postbifurcal, slightly to right of median line.

DISCUSSION

KEY TO SPECIES OF

Pseudancyrocephalus FROM HAWAIIAN FISHES

Ovary triangular, 20-60 X 25-88 ¡x, immediately pretesticular. Eggs round, 81 ¡x in diameter, with a relatively short filament terminating in a knob. Vagina funnel-shaped, provided with longitudinal muscle fibers, opening ventral to right cecum or ventrolaterally at about level of base of cirrus; vaginal duct arising from base of vagina. Seminal receptacle small, giving off sideways a narrow sclerotized canalis receptaculi seminis, running backward to dorsolateral side of ovary. Vitellaria co-extensive with intestine, confluent anteriorly and posteriorly. This species is characterized by the structure of the anchor complex and of the terminal genitalia.

Cirrus tubular, long, somewhat C-shaped, with two accessory pieces; canalis receptaculi seminis present:

2

Cirrus long, spicular, coiled; vaginal duct convoluted, without canalis receptaculi seminis: P. longispicularis Cirrus and accessory piece C-shaped, short, close parallel to each other; canalis receptaculi seminis present: P. duplicatus Cirrus expanded distally into a transversely striated wing; accessory piece a curved sclerotized rod; canalis receptaculi seminis present:

P. kala

Accessory piece simple at tip, recurved or not; vagina funnelshaped: P. nasonis

Dactylogyridae

105

Accessory pieces bifid at tip; vagina cylindrical, long, more P. longicirrus muscular: 77 HABITAT

HOLOTYPE DESCRIPTION

DISCUSSION

Neohaliotrema

maomao Yamaguti, 1965

FIGURE 7 7

Gill of Abudefduf abdominalis (local name "maomao"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 5. (Based on 25 whole mounts.) Body very small, elongate, 0.23-0.44 X 0.06-0.09 mm. Opisthohaptor well marked off from body proper, 42-100 ¡x wide at level of horn-like lateral projections, each of which is tipped with marginal hooklets. At this level there is a pair of spines 25-35 ¡x long in form of a V in the dorsal median field with acute points directed anterolaterad; immediately ventrolateral to this another pair of very slender spines of nearly the same length together with the anterior median pair of marginal hooklets. Anchor apparatus of opisthohaptor consisting of two pairs of anchors and two median bars; dorsal anchor 40-60 ¡x long from tip of dorsal root to height of curve of blade; dorsal bar V-shaped, 25-50 p transversely from end to end; ventral anchor 32-53 ¡x long from tip of ventral root to height of curve of blade; ventral bar overlapping dorsal bar, curved angularly on each side of median line, 32-53 ¡x transversely from end to end. Immediately in front of the median bars there is a pair of nearly round windows separated by a narrow median string of tissue. Head with two inconspicuous lobes studded with head organs on each side. Only one pair of compact eyespots anterior to pharynx. Pharynx 12-20 X 12-19 ¡x; esophagus practically absent. Intestinal limbs united posterior to testis. Testis elliptical, 25-81 X 17-42 ¡x, situated at junction of middle with posterior third of body. Vas deferens running forward ventral to left intestinal limb, distended with sperm, opening into base of cirrus. Cirrus narrow, tubular, twisted, sheathed except for base and pointed distal portion. Prostatic reservoir tubular or claviform, 6-9 /x wide, immediately behind cirrus, with its base directed backward. Prostatic cells massed together around base of prostatic reservoir. Ovary retort-shaped, 25-47 x /*> immediately pretesticular. Vagina very much reduced; its rudiment may be recognizable ventral to seminal receptacle; latter oval, 13-23 X 10-16 ¡x. A large shrunken egg 70-77 X 37-39 ¡x was often observed hanging out of genital pore, with its posterior polar filament 0.18-0.32 mm long and enlarged at tip. Vitellaria coextensive with intestine. This species is characterized by possessing two pairs of spiniform sclerites on the dorsal side of the base of the opisthohaptor and a pair of round windows behind the sclerites, and by the vas deferens running forward ventral to the left intestinal limb without looping around it. The fact that there is only one pair of eyespots without exception is also worth noting. For further details, see Pacific Science 1 9 ( 1 ) :62-64_

io6

78 HABITAT

HOLOTYPE DESCRIPTION

DISCUSSION

79 HABITAT HOLOTYPE DESCRIPTION

Pseudohaliotrematoides aurígae n. sp.

FIGURE 7 8

Gills of Chaetodon auriga; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 149. (Based on 1 9 whole mounts.) Body flattened subcylindrical, 0 . 3 8 - 0 . 7 6 mm long, up to 6 0 - 1 2 0 /t wide in middle third. Opisthohaptor well constricted off from body proper, usually 1 0 0 - 1 5 0 p. wide at level of lateral projections; dorsal anchor 4 2 - 6 5 ¡x lineally from tip of dorsal root to height of curve of blade; dorsal bar slightly undulating, 5 8 - 8 8 ¡x long; ventral anchor apparently fenestrated, 5 0 - 5 8 ¡x lineally from tip of ventral root to height of curve of blade; ventral bar coathanger-shaped, slender 6 0 - 8 5 ¡x long; marginal hooklets on lateral projection about 10 ¡x long. Head 2-lobed on each side, 3 5 - 6 5 ¡x wide at level of posterior lobes, with well developed head organs. Two pairs of eyespots may be dissociated. Pharynx 15-35 X 12-28 ft; esophagus very short; ceca united posteriorly at middle of posterior third of body. Testis elongate oval, 4 0 - 7 5 X 2 2 - 4 6 ¡x, situated largely at posterior part of middle third of body. Vas deferens running forward medial to right or left (usually left) cecum; no distinct seminal vesicle. Cirrus tubular, fine, terminating in a gradually increasing swelling, with bell-shaped base 10-13 f- wide, near which it may or may not turn back on itself. A fine, whip-like, broad-based, accessory filament arising from base of cirrus, reaching to near distal end of cirrus, where it terminates in a very fine point. Prostatic cells in inter- and extra-cecal fields from immediately behind intestinal bifurcation down to level of transverse vitelline duct. Prostatic reservoir inverted claviform, 2 3 - 4 0 X 7.5-15 ¡x, situated longitudinally to left of copulatory organ. Genital pore median, shortly postbifurcal. Ovary oval, 3 2 - 5 0 X 1 5 - 2 7 ¡x, postequatorial, immediately pretesticular. In front of the ovary large, clear shell gland cells are massed together. Seminal receptacle small. Only one abortive uterine egg observed, 70 X 50 ft, somewhat shrunken, without polar filament. Vagina cylindrical, 2 0 - 3 0 X 5 - 1 2 /x, with very thick wall, opening ventral to right cecum or nearer right body margin a little behind base of cirrus; vaginal duct arising from posterior end of vagina. Vitellaria co-extensive with intestine. This species is distinguished from Pseudohaliotrematoides triangulovagina n. sp. from the related host species by the simpler structure of the copulatory organ and vagina. The specific name refers to the specific name of the host.

Pseudohaliotrematoides falcatus n. sp.

FIGURE 7 9

Gills of Holocentrus spinifer; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 150. (Based on eight whole mounts.) Body small, slender, flattened sub-

Dactylogyridae

DISCUSSION

80 HABITAT HOLOTYPE DESCRIPTION

107

cylindrical, 0 . 7 - 1 . 0 mm in length, with maximum width of 0 . 1 2 - 0 . 1 8 mm in midregion. Opisthohaptor not well marked off from body proper, 80100 p wide; marginal hooklets 1 1 - 1 2 p long. Dorsal anchor 5 0 - 6 6 p long lineally from tip of dorsal root to height of curve of blade, with ventral root very much reduced; dorsal bar 3 7 - 4 6 p long; ventral anchor similar and equal to dorsal anchor; dorsal root of this anchor very much reduced; ventral bar a little shorter than dorsal bar, 2 5 - 3 7 >*• l° n §- Head approximately trapezoidal, 6 3 - 1 0 5 p wide, with two pairs of head organs. Eyespots dissociated. Pharynx oval, 3 0 - 3 7 X 1 8 - 3 5 /*> esophagus short; ceca united posteriorly about middle of posterior third of body. Testis elliptical, 7 0 - 1 0 5 X 1 8 - 3 0 p, median, just postequatorial. Vas deferens running straight forward, forming inverted claviform seminal vesicle anteriorly. Cirrus 3 0 - 4 0 p long, falcate, surmounted at its distal half by an elongate cuticular cap, with bell-shaped base. There are two prostatic reservoirs close together immediately dorsolateral to straight proximal portion of cirrus; larger right reservoir claviform, 16-37 X 5~~9 ^ smaller left one rather tubular, 11-23 X 2-4 p. Prostatic cells apparently not divided into two groups. Genital pore median, 0.12 mm posterior to pharynx in the type 1.0 mm long. Ovary fusiform to elliptical, larger than testis, 8 1 - 1 1 6 X 2 3 - 4 6 p, median, immediately pretesticular. Seminal receptacle small, oval, 23 X 18 /x in the type. Vagina elongate, 40 X 12 p in the type, lying obliquely on right side in anterior part of middle third of body, opening on right margin of body at junction of anterior with middle third of body. Vitellaria co-extensive with intestine. This species is characterized by the possession of two prostatic reservoirs, as is Pseudohaliotrematoides chaetopteri (Caballero et Bravo-Hollis, I 9 6 0 ) , but the two species differ in the structure of the cirrus, haptoral apparatus, etc.

Pseudohaliotrematoides microphallus n. sp.

FIGURE 80

Gills of Chaetodon auriga; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 5 1 . (Based on 1 5 whole mounts.) Body very small, rather plump, 0 . 3 5 0.48 mm long, up to 1 0 0 - 1 2 0 p wide in ovariotesticular region. Opisthohaptor rhomboid, well constricted off from body proper, 8 0 - 1 1 0 p in diameter at level of lateral projections; dorsal anchor 2 8 - 3 5 p long from tip of very prominent dorsal root to height of curve of blade; dorsal bar nearly straight, slightly swollen medianly, 25-31 p long; ventral anchor on rom 23-33 P l g f tip of ventral root to height of curve of blade; ventral bar slightly arcuate, 23-31 p long; marginal hooklets 11 p long. Head rather truncate, 3 4 - 5 8 p wide, with two pairs of conspicuous lobes, each of which contains a head organ. Compact eyespots in one pair or two. Pharynx globular, 16-28 p in diameter; esophagus practically absent; ceca united posterior to testis.

io8

DISCUSSION

81

HABITAT

HOLOTYPE DESCRIPTION

Testis oval to elliptical, 58-116 X 23-58 ¡x, at junction of middle with posterior third of body. Vas deferens running straight forward in median field, forming seminal vesicle before opening into base of cirrus from behind. Cirrus very small, sigmoid, only 11-23 ¡x long lineally from circular enlarged base to tip, situated just posterior to intestinal bifurcation. Prostatic reservoir very small, claviform, directed backward from base of cirrus, surrounded by prostatic cells. Genital pore midventral, just postbifurcal. Ovary oval, produced anteriorly, 42-70 X 23-35 ¡i, immediately pretesticular, equatorial. Shell gland cells occupying a large, clear, preovarian space. No eggs observed. Vagina tubular or fusiform, narrow, 23-30 X 2-4.6 ja, opening on right margin of body at junction of anterior with middle third of body; vaginal duct as direct continuation of vagina, narrow. Seminal receptacle small, oval. Vitellaria co-extensive with intestine; transverse vitelline duct anterior to above mentioned clear space. This species is characterized by the extremely small, rather simple sigmoid cirrus; hence the specific name. It is to be noted that the shell gland complex is clear and occupies a large preovarian median space.

Pseudohdliotrematoides

recurvatus

n. sp.

FIGURE

81

Gills of Strongylura gigantea; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 152. (Based on 12 whole mounts.) Body elongate flattened, 1.0-1.5X0.250.31 mm, tapered anteriorly. Opisthohaptor constricted off from body proper and flattened anteroposteriorly, 0.3 mm wide in the type 1.18 mm long, with two pairs of similar anchors, two long slender similar bars, and six pairs of larval marginal hooklets 11-14 /a long; anchors 27-37 l°nS from tip of longer root (dorsal root in dorsal anchor, ventral root in ventral anchor) to height of curve of blade; both bars somewhat arcuate, 74-93 n long. Head trapezoidal, 0.1-0.15 m m base, with poorly developed head organs. A pair of compact eyespots at level of pharynx. Pharynx elliptical, weakly muscular, 16-21 X 9-14 p; a short esophagus present; ceca united posteriorly. Testis longitudinally elongated oval, irregularly incised, 0.2-0.3 X 0.080.12 mm, at junction of middle with posterior third of body. Seminal vesicle up to 23-37 w ^ e , sigmoid, extending transversely across prostatic reservoir on its ventral side, with its attenuated distal end opening into cirrus together with two efferent prostatic ducts. Prostatic reservoir tubular, up to 20-40 ¡x wide, recurved proximally, with its rounded proximal end directed forward; its attenuated distal end opening into cirrus alongside another narrower prostatic duct and attenuated distal end of seminal vesicle. Prostatic cells profusely developed, divided on the left side into two (an anterior and a posterior) groups as shown in the figure. On the right side, however, a smaller group of prostatic cells lies anterolateral to

Dactylogyridae

DISCUSSION

82 HABITAT HOLOTYPE DESCRIPTION

109

the cirrus; the ducts coming from these cells are eventually bundled into one efferent duct which opens into the cirrus alongside the other wider prostatic duct and seminal vesicle as mentioned above. Cirrus 7 0 - 8 0 ¡x long, 2-lobed at base, opening anteriorly in form of a petaloid structure, with the thickened dorsal margin produced into a flute-like appendage hanging down along the dorsolateral margin of the cirrus; its stalk-like portion is provided with circular muscle fibers. Genital pore midventral, just postbifurcal. Ovary longitudinally elongated, 0.1-0.15 m m immediately pretesticular. Shell gland cells large, scattered around anterior part of ovary. Uterus running forward ventral to seminal vesicle and prostatic reservoir. No eggs observed. Vagina cup-shaped, well provided outside with circular muscles, 3 5 - 5 8 X 2 3 - 5 8 n, opening on right margin of body at level of base of cirrus; vaginal duct narrow, arising from base of vagina, running posteromesad, forming a small sphincter just before joining seminal receptacle. Seminal receptacle elliptical to fusiform, situated slightly to right of median line immediately anterior to transverse vitelline duct, overlapping recurved prostatic reservoir in the type. Vitellaria commencing at level of genital pore, leaving beginning of intestine free. Transverse vitelline duct immediately behind convex posterior end of prostatic reservoir or a little away from it. The median vesicle containing sperm at this transverse vitelline duct is regarded as an expanded fertilization chamber, because it receives the germiduct at its posterior end. This species is characterized by the incised testis, recurved prostatic reservoir, sigmoid seminal vesicle, petaloid cirrus, and long slender haptoral bars. The specific name refers to the most conspicuous recurved prostatic reservoir.

Pseudohaliotrematoides

triangulovagina

n. sp.

FIGURE 82

Gills of Forcipiger longirostris (type host), Chaetodon auriga and C. multicinctus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 5 3 . (Based on nine whole mounts.) Body small, rather slender, 0.38-0.46 mm in length, with maximum width of 6 0 - 1 2 0 ¡x at level of testis or ovary. Opisthohaptor well set off from body proper, 5 5 - 9 5 ju. wide at level of lateral projections; dorsal anchor 2 7 - 3 8 ¡x long lineally from tip of long dorsal root to height of curve of blade; ventral root of this anchor almost completely reduced; dorsal bar nearly straight, 3 0 - 3 5 n long; ventral anchor 2 7 - 3 3 n long from tip of ventral root to height of curve of blade; ventral bar slightly arcuate, recurved at both ends, 2 7 - 3 8 ¡x long; marginal hooklets 9 - 1 0 ¡x long. Head rounded conical, 3 5 - 5 8 ¡x wide. Two pairs of eyespots anterior to pharynx, dissociated or not. Pharynx 15-28 X 1 2 26 /t; esophagus short or practically absent; ceca united posterior to testis in anterior part of caudal third of body.

no

DISCUSSION

83 HABITAT HOLOTYPE DESCRIPTION

Testis elliptical, 55-75 x 2 5 - 4 2 ¡x, postequatorial. Vas deferens not looping around left cecum although bending outward at level of vagina. Copulatory organ complex, consisting of a fine tubular, spiral cirrus provided with longitudinal muscle fibers extending its whole length and a complicated accessory piece, the anterior end of which is cheliform and supports the other parts of the accessory piece, enclosing the distal portion of the cirrus. Prostatic reservoir claviform, slender, directed backward from base of cirrus, with prostatic cells behind. Genital pore midventral, postbifurcal. Ovary oblong, 3 7 - 5 4 X 1 7 - 3 3 ¡x, immediately pretesticular. Vagina 2 0 30 X 10-12 /x, triangular in dorsoventral view, with a vacuolar space in its wall posteriorly, situated at a considerable distance posterior to cirrus; vaginal duct not observed. Seminal receptacle small, overlapping transverse vitelline duct. Egg observed in one specimen only, measuring 65 /* long in shrunken condition. Vitellaria co-extensive with intestine. Upon cursory examination this species appears very closely related in general anatomy to Pseudohaliotrematoides microphallus n. sp. from the same host species, but differs from it in the structure of the vagina and cirrus. The specific name refers to the peculiar triangular shape of the vagina.

Pseudohaliotrematoides zaticli n. sp.

FIGURE 8 3

Gills of Zaticlus catiescens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 5 4 . (Based on 1 5 whole mounts.) Body flattened subcylindrical, 0 . 4 3 - 0 . 7 5 X 0 . 0 9 - 0 . 1 7 mm, with indistinct eyespots. Opisthohaptor a little narrower than body proper, from which it is shallowly constricted off; marginal hooklets about 13 /x long; dorsal anchor similar in structure to ventral anchor, 4 0 - 5 0 ¡x lineally from tip of dorsal root to height of curve of blade; dorsal bar V-shaped, 3 2 - 5 0 p from end to end; ventral anchor 3 7 - 5 0 p lineally from tip of ventral root to height of curve of blade, with reduced dorsal root; ventral bar 3 7 - 5 0 /x long, with prominent horn-like projection articulating with reduced dorsal root of ventral anchor. Head trapezoidal, 5 2 - 7 5 ¡x wide, with three pairs of head organs. Pharynx 17-40 X 13-33 esophagus short; ceca united posteriorly. Testis elliptical, 5 5 - 1 0 0 X 2 5 - 7 5 /*> a t junction of middle with posterior third of body. Vas deferens running forward medial to left cecum, bending back on itself anteriorly to form inverted retort-shaped seminal vesicle near base of cirrus. Prostatic cells densely massed together in front of base of prostatic reservoir, partly in extracecal field at the same level. Prostatic reservoir inverted retort-shaped, to right of seminal vesicle. Copulatory organ consisting of a common conical base 17-20 n in diameter, a narrowly flanged, spirally coiled, tubular cirrus proper which is 68-88 ¡x long lineally and somewhat enlarged at the truncate distal end, and a distally

Dactylogyrìdae

DISCUSSION

KEY TO SPECIES OF

Pseudoholiotrematoides FROM HAWAIIAN FISHES

84 HABITAT HOLOTYPE DESCRIPTION

m

solid accessory prong which is 75-95 long lineally and barbed distal to its middle. Genital pore a little to right of median line at about middle of anterior third of body. Ovary elongate, 35-50 X 17-30 p, immediately pretesticular. No eggs observed. Vagina elongate pyriform, 40-65 X 12-20 //., situated obliquely at junction of anterior with middle third of body, opening on right margin of body; its wall consisting of well developed outer circular and inner longitudinal muscle fibers. Vaginal duct arising from near base of vagina. Seminal receptacle very small. This species is characterized by the structure of the haptoral bars and copulatory organ and by the subterminal origin of the vaginal duct.

Vagina triangular, with vacuolar space in its wall; copulatory organ of very complex structure: P. triangulovagina Vagina simple, copulatory organ not very complex: 2 Copulatory organ without accessory piece: 3 Copulatory organ with accessory piece: 4 Cirrus falcate; prostatic reservoir double, directed forward: P. falcatus Cirrus tubular, sigmoid; prostatic reservoir single, directed backward: P. microphallus Cirrus petaloid; prostatic reservoir single, strongly recurved proximally, directed backward: P. recurvatus Cirrus tubular, spirally coiled, flanged; accessory piece barbed, arising from common conical base with cirrus; vaginal duct arising subterminally from vagina: P. zancli Cirrus with bell-shaped base; accessory piece not barbed; vaginal duct arising terminally from vagina : P. aurigae

Parancyrocephaloides

daetylopteri

n. sp.

FIGURE

84

Gills of Dactylopterus orientalis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 155. (Based on four whole mounts.) Body elongate, 1.1-1.45 mm long, up to 0.22-0.35 m m level testis. Opisthohaptor short, 0.12-0.15 mm wide, well constricted off from body proper; dorsal anchor with stout Vshaped root, 56-68 p long from tip of dorsal root to height of curve of blade; dorsal bar absent; ventral anchor with stout root, 46-58 p. long from tip of longer ventral root to height of curve of blade; ventral bar Vshaped, 25-35 f- hneally from end to end; marginal hooklets 1 1 - 1 2 ¡t. long. Head rounded at apex, 0.11-0.13 mm wide, with head organs along sloping lateral margins. Two pairs of compact eyespots dorsal to pharynx. Pharynx 60 X 70 ¡i; esophagus short; ceca wide, united some distance behind testis. Testis 0.26-0.3 X o.iy-0.2 mm, folded back on itself just as in the type species of the genus, situated largely in middle third of body. Vas deferens narrow, running forward in submedian field, forming two separate seminal

112

DISCUSSION

85 HABITAT

HOLOTYPE DESCRIPTION

vesicles near copulatory organ. Cirrus 60-75 ¡x. in total length, enclosed, except for apex, in sheath-like bolster of diagonal muscle fibers, consisting of a wrench-shaped cirrus proper and a cylindrical, muscular, proximal portion; this latter portion 44 X 11 in the type, always a little longer than cirrus proper. There are two prostatic reservoirs; one is rather cylindrical, up to 28 p wide, curved in form of letter C around the proximal portion of the cirrus, with thick wall of longitudinal muscle fibers; the other is also tubular, sigmoid, and lies dextrodorsal to the cirrus. Prostatic cells immediately anterior to base of prostatic reservoir, partly in extracecal fields. Genital pore midventral, just behind intestinal bifurcation. Ovary retort-shaped, 58-100 ¡¡. wide, immediately pretesticular, slightly to right of median line. Vagina cup-shaped, 23-35 ¡x wide at its opening which lies ventrally close to the right margin of the body nearly halfway between the cirrus and the ovary; vaginal duct very narrow, running obliquely inward from base of vagina, emptying into seminal receptacle, from which arises on each side a short canalis receptaculi seminis running outward and apparently ending blindly. Uterus containing one egg at a time; eggs triangular, as long as wide (70-72 /*), with terminally knobbed filament at one corner. Vitellaria co-extensive with intestine. This species differs from the most closely related Parancyrocephaloides daieoci Yamaguti, 1938 in the ranges of measurements of the anchors being separate and in the structure and position of the prostatic reservoirs. The canalis receptaculi seminis may have been overlooked in P. daicoci, but I am unable to confirm this while staying in the United States.

Murraytrematoides kuhliae n. sp.

FIGURE 85

Gills of Kuhlia sandvicensis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 156. (Based on 23 whole mounts.) Body flattened subcylindrical, 0.75-1.32 X 0.08-0.18 mm. Opisthohaptor bilobed, well marked off from body proper, 70-100 ft. wide, provided symmetrically with a small number of minute marginal hooklets about 8 ¡i long, two pairs of similar anchors, an unpaired horseshoe- or inverted V-shaped median bar, and a pair of submedian bars; each anchor bent at right angles near its pointed tip, with a very prominent guard, outer pair 25-40 fi, inner 35-48 ¡x, from height of curve to base lineally; submedian bar 37-50 ¡i. long, oblique, somewhat thickened at lateral half which lies dorsal to roots of anchors, with its blunt curved end apparently articulating with the root of the dorsal anchor, thinning out medially to form a sleeve-like flange which appears to articulate with the convex side of the median bar bearing a nodular protuberance on each side of the median line. Conspicuous muscle bundles coming from inner wall of body proper are attached to the roots of the anchors and median bar. Two pairs of eyespots close together anterior to pharynx. Numerous

Dactylogyridae

DISCUSSION

86 HABITAT

HOLOTYPE DESCRIPTION

113

head organs along lateral margins of rounded head 66-110 ^ wide. Pharynx barrel-shaped, 30-75 X 25-60 /¿; esophagus short; ceca terminating separately some distance anterior to opisthohaptor. Testis oval to elliptical, with smooth margin, 60-150 X 30-100 ¡x, equatorial. Vas deferens dilated to form seminal vesicle as it turns round the left cecum. Ejaculatory duct coiled anterior to cirrus. Cirrus hook-shaped, 32-43 ¡i long, with rounded base, from which the poorly sclerotized capsule enclosing the cirrus extends to the tip of the cirrus, and is provided on one side of the proximal portion with a transverse band of fine muscle fibers. Prostatic reservoir a small sac only 7-8 ¡x wide, situated beside base of cirrus, with prostatic cells around its base. Genital pore midventral, at tip of cirrus at a distance of one-third of body length from anterior end. Ovary extending transversely and encircling right cecum. A small seminal receptacle opening into fertilization chamber. Uterus midventral, containing no eggs. Vitellaria co-extensive with intestine. Vagina cupshaped, with cuticular wall which is irregularly thickened and partly sclerotized; its funnel-shaped opening lies on the right margin a little posterior to the genital pore. The present species differs from the most closely related Murraytrematoides ditrematis Yamaguti, 1958 in the roots of the anchors being longer, in the structure of the middle and lateral bars, in the seminal vesicle being formed as the vas deferens turns round the left cecum, and in the structure of «the copulatory organ.

Pseudempleurosoma carangis Yamaguti, 1965

FIGURE

86

Gill and pharynx of Caranx lugubris (type host), C. sexfasciatus, and Myripristis berndti; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 6. (Based on 30 whole mounts.) Body flattened subcylindrical, 0.8-1.32 X 0.15-0.34 mm, tapered posteriorly. Opisthohaptor shallowly constricted off from body proper, truncate behind, 70-90 ¡i wide, with two pairs of dissimilar anchors and 14 marginal hooklets 1 0 - 1 5 ¡t, long; anterior medial hooklets abnormally large; dorsal anchors stout, 47-53 /J. from tip of ventral root to height of curve of blade, dorsal root shorter than ventral root, turned medially to form a dorsal swelling, at the inner end of which the anchor articulates with its fellow of the other side by means of a median bar; this bar looks like an approximately quadrangular shield, but its convex anterior border, 12.5-15 ¡t, lineally from end to end, is thickened in form of an inverted V or an arc. Ventral anchors very small, simple, only 1 0 - 1 5 ¡x long, wider apart one from the other than stout dorsal anchors, with root articulated with a simple oblique bar about 1 5 ju, long. Head trapezoidal, with a compact group of head glands anterolaterally. Two pairs of eyespots dorsal to mouth. Pharynx globular, 45-65 X 57-75 Esophagus wide, up to 40-50 ¡t long, with a group of postpharyngeal gland

114

DISCUSSION

TABLE

3

cells on each side. Ceca comparatively wide, united posterior to testis at a variable distance in different individuals, sometimes far posteriorly, each with a number of undivided diverticula laterally; posterior common cecum also with diverticula on each side, terminating blindly some distance anterior to opisthohaptor. Testis round to oval, 32-85 x 25-60 /i, median, toward middle of anterior half of body. Seminal vesicle elongate, at base of copulatory apparatus. Cirrus tubular, slender, about 50 long, enclosed in a cylindrical sheath for its proximal portion, but free in the distal portion and twisted at junction of the two portions just at the level of the distal end of the sheath which is armed with a circle of very fine spiniform structures. Genital atrium median, just postbifurcal; into this atrium projects a small, muscular acetabular disc 22-30 ¡t. in diameter from the anterolateral side; the posteromedial border of the disc sometimes showing in the postbifurcal median genital pore. Ovary 50-100 X 50-78 ¡x, turned back on itself between testis and transverse vitelline duct, with its distal end turned forward. Neither seminal receptacle nor vagina. Eggs oval, without polar filament, about 90 X 70 /i in life, one at a time. Vitellaria forming numerous transversely elongated lobes intercalated between cecal diverticula and connected medially with paired longitudinal vitelline ducts commencing at level of intestinal bifurcation or genital pore; some of the posterior lobes of the two sides are confluent, although the level of the anterior limit of this union varies individually. This genus resembles Diplectanotrema Johnston and Tiegs, 1922 on the one hand, and Empleurosoma Johnston and Tiegs, 1922 on the other; the differences are shown in the following table: COMPARISON OF Pseudempleurosoma

CHARACTER

Family

87 HABITAT

Diplectanotrema

WITH RELATED G E N E R A

Empleurosoma

Pseudempleurosoma

Intestinal ceca

separate

united posteriorly

united posteriorly

Vagina

present

absent

absent

Seminal receptacle

present

?

absent

Vitellaria

separate

separate

confluent posteriorly

D I P L E C T A N I D A E Bychowsky, 1957

Nasobranchitrema pacificum Yamaguti, 1965

FIGURE

87

Gill of Naso hexacanthus (type host), N. lituratus, N. brevirostris and N. annulatus; Hawaii.

Diplectanidae

HOLOTYPE DESCRIPTION

115

U.S. Nat. Mus. Helm. Coll., S.Y. No. 7. (Based on 12 whole mounts.) Body elongate subcylindrical, slightly tapering anteriorly, 0.95-1.5 mm long, 0.11-0.26 mm wide at level of testis. Opisthohaptor 0.14-0.25 mm wide, well set off from body proper, with two pairs of anchors, three separate bars, and several pairs of marginal hooklets about 10 /* long at level of lateral prominences; dorsal anchors 45-55 ¡x long lineally from tip of longer dorsal root to height of curve of blade, dorsal to lateral portion of ventral bar; ventral anchors 35-50 ¡x long lineally from tip of base to height of curve of blade, with obliquely flattened base articulating with ventral bar; of the three separate bars, the unpaired median dorsal 50-80 ¡x long is constricted at middle, each half swollen medially and resting on transverse dorsal ledge of submedian bar, tapered laterally; submedian bars meeting in median line, 55-80 ¡x long, each swollen at medial portion bearing above mentioned transverse ledge. Head trapezoidal, 0.07-0.15 mm wide at base, with several head organs along each lateral sloping margin; head glands well developed laterally at level of pharynx. Two pairs of eyespots anterior to pharynx. Pharynx globular, 27-80 ¡x in diameter; esophagus practically absent; ceca simple, terminating separately posterior to testis at about middle of posterior third of body. Testis oval, 0.1-0.2 X 0.045-0.12 mm, situated at posterior end of middle third of body. Vas deferens running forward along medial side of left and right intestinal limbs, but not looping around either of them, winding anteriorly before turning backward; ejaculatory duct running backward alongside efferent duct of prostatic reservoir. Copulatory organ complex in structure; main portion consisting of C-shaped cirrus from which two winding tubules arise in opposite directions, one reaching to a ring-like independent tubular structure and the other looping around the distal portion of the cirrus which turns back on itself to open into the genital pore. The proximal portion of the cirrus is produced forward into a clawlike structure, but there is another wide cuticular tube arising from near origin of the two above mentioned tubules and terminating in a slight enlargement where the ejaculatory duct and the prostatic ducts empty into the cirrus. Prostatic reservoir elongate oval to elliptical, 40-75 X 2550 ¡i, behind intestinal bifurcation, with its descending duct running alongside descending ejaculatory duct and opening into base of cirrus. Genital pore nearly median, some distance posterior to intestinal bifurcation.

DISCUSSION

Ovary heart-shaped or irregular in shape, 50-100 X 30-100 ¡x, immediately pretesticular. Vagina represented by a well cuticularized, undulating, probably non-functional tubule about 50 ¡x long and lying obliquely posterodextral to the copulatory organ. Vaginal duct narrow, descending from proximal end of vagina toward shell gland complex. No seminal receptacle. Shrunken egg observed in utero is about 80 ¡x long, produced backward into a rigid filament. Vitellaria co-extensive with intestine; transverse vitelline duct in front of shell gland complex. This genus is characterized by the possession of three separate haptoral

Il 6

bars and a very complex copulatory organ. From the structure of the haptoral apparatus there is no doubt that it belongs to Diplectanidae Bychowsky, 1957, but it differs from any of the known genera of this family by the absence of adhesive plaques or squamodiscs.

88 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

89 HABITAT HOLOTYPE

Diplectanum curvivagina n. sp.

FIGURE 88

Gills of Pristipomoides sieboldii (type host) and Arnillo auricilla; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 157. (Based on seven specimens from type host and eight from other host.) Body elongate fusiform, 0 . 7 6 - 1 . 2 mm long, up to 0 . 1 8 - 0 . 3 4 mm wide at a postequatorial level. Opisthohaptor 1 6 0 - 2 2 0 p. wide, well constricted off from body proper; squamodisc circular, 4 5 - 6 0 /x in diameter, consisting of 8 - 1 0 concentric rows of scale-like ridges. Dorsal anchor 5 2 - 6 3 ju long lineally from tip of longer root to height of curve of blade; ventral anchor stouter than dorsal, 6 2 - 7 3 ¡x long from tip of long ventral root to height of curve of blade; median bar 5 2 - 6 5 /x long, tapered at both ends; submedian bar gently sigmoid, with nodular dorsal projection near rounded inner end, 5 7 - 7 3 /t long; marginal hooklets 8 - 1 0 ¡x long. Head trapezoidal, 9 0 - 1 3 0 n wide at base, with several pairs of marginal head organs. Two pairs of eyespots anterior to pharynx. Pharynx 5 5 - 6 5 X 4 0 - 6 0 p.; esophagus practically absent; ceca terminating separately at posterior end of body proper. Testis small, 3 0 - 4 5 X 2 0 - 3 5 /*» equatorial. Vas deferens winding forward in median field and opening into base of cirrus. Cirrus tubular, curved like a letter C, 1 0 0 - 1 2 0 ju. long. A small tubular prostatic reservoir dorsal to basal portion of cirrus; prostatic cells poorly developed posterior to base of reservoir. Genital pore median, immediately behind intestinal bifurcation. Ovary elongate oval, 4 0 - 6 4 X 1 5 - 4 5 ¡x, immediately pretesticular, with shell gland in front. Uterus ventral to vas deferens, provided with circular muscle fibers. Only one egg observed, elliptical, filamented, 83 X 40 ¡x. Vagina tubular, about 4 0 - 4 5 \x long, curved like a semicircle, opening ventral to left cecum at level of cirrus; vaginal duct running backward toward shell gland; oval receptaculum seminis vaginae present. Vitellaria co-extensive with intestine. This species is characterized by the anterior position and the peculiar shape of the vagina. The specific name refers to the curved vagina. The C-shaped cirrus with poorly developed prostatic complex is also a differential character.

Diplectanum diplobulbus n. sp. Gills of Kyphosus cinerascens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 158.

FIGURE 89

Diplectanidae

DESCRIPTION

DISCUSSION

90 HABITAT HOLOTYPE DESCRIPTION

117

(Based on seven whole mounts.) Body small, elongate, 0 . 7 - 0 . 9 4 mm long, up to 0 . 1 2 - 0 . 1 9 mm wide in testicular region. Opisthohaptor constricted off from body proper, 0 . 1 8 mm wide; squamodisc 0 . 1 - 0 . 1 5 mm wide, consisting of 12-18 concentric denticulate cuticular ridges; median bar 1151 3 5 p. long; lateral bar 4 5 - 5 5 n long; dorsal anchor 2 7 - 3 3 /x long lineally from anterior end of obliquely truncated end to tip of right-angled blade; ventral anchor with bifurcate root, 3 2 - 4 3 ¡x long from tip of dorsal root to height of curve of blade; marginal hooklets at each prominent lateral corner of opisthohaptor, 7 . 5 - 1 0 ¡x long. Head with prominent rounded apex, 8 0 - 1 1 0 jh wide at level of lateral lobes; head organs strongly developed. Two pairs of eyespots immediately anterior to pharynx. Pharynx 3 2 - 5 5 X 3 0 - 5 0 jit; ceca simple, terminating separately in anterior half of posterior third of body. Testis elliptical, 6 8 - 1 7 0 X 5 0 - 1 0 0 ¡x, postequatorial. Vas deferens passing dorsal to ovary and then dilated to form retort-shaped seminal vesicle 2 2 - 3 8 ft. wide; narrow ejaculatory duct winding and forming two successive ejaculatory bulbs, of which the posterior is slightly curved, 10-15 X 7 . 5 - 1 0 ix, and lies on the left of the backwardly directed cirrus, whereas the anterior is very small, spherical, 7-10 ¡x in diameter, and lies close to the base of the cirrus. Cirrus plug-shaped, 2 5 - 4 5 X 1 0 - 1 8 ¡x, with heavy sclerotized lining, projecting backward midventrally behind intestinal bifurcation. Prostatic complex immediately in front of base of cirrus. Ovary retort-shaped, 4 0 - 7 5 fx wide, immediately pretesticular. Shell gland complex situated to right of seminal vesicle. Vagina small, apparently opening just behind tip of cirrus a little to left of median line; vaginal duct narrow, opening into elongate seminal receptacle; the connection of the latter with the germiduct not clearly made out. Eggs not observed. Vitellaria entirely co-extensive with intestine. This species very closely resembles the young form of Acleotrema girellae of Johnston et Tiegs, 1922, which was confused with the adult worm of A. girellae by the Australian authors, but differs from it distinctly in possessing two muscular ejaculatory bulbs instead of one. The specific name refers to this character.

Diplectanum

kuhliae n. sp.

FIGURE 90

Gills of Kuhlia sciTidvicensis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 5 9 . (Based on 1 7 whole mounts.) Body subcylindrical, tapered anteriorly, 0 . 6 - 1 . 1 5 X 0 . 0 5 - 0 . 1 5 mm. Opisthohaptor not very well marked off from body proper, provided on dorsal and ventral sides with a squamodisc 4063 ¡X in diameter and consisting of partly concentric, partly transverse, rows of 15-20 cuticular denticular ridges. Of the two pairs of similar anchors one pair is 37-55 ¡x long and the other 3 2 - 4 3 ¡x long; of the three transverse bars the middle is U- or V-shaped, 2 3 - 5 0 ¡x transversely from end to end; paired submedian bars enlarged medially and tapered at lateral

n8

DISCUSSION

91 HABITAT HOLOTYPE DESCRIPTION

half, 3 2 - 5 0 ¡x long. Head with prominent rounded apex and several pairs of head organs. Two pairs of eyespots anterodorsal to pharynx. Pharynx bulbous, 3 0 - 4 5 X 2 8 - 4 5 ju; esophagus very short; ceca not confluent posteriorly, though terminating close together. Testis elliptical, 6 3 - 1 4 0 X 3 0 - 9 3 ¡x, equatorial or postequatorial. Vas deferens passing dorsal to left portion of ovary, emptying at base of cirrus without forming ejaculatory bulb. Cirrus curved anteriorly and terminating in acute point which appears to be in contact with the apex of the accessory piece. A simple, slender, sigmoid rod originating from the base of the cirrus, lying almost parallel to cirrus, and shutting into a small muscle bulb situated very close to genital pore. Immediately in front of the cirrus is a spherical prostatic reservoir opening into the cirrus at its base and well provided with circular muscle fibers. Ovary 4 0 - 1 1 0 X 3 0 - 9 2 fi, in midregion of body, with shell gland complex in front. Vitellaria co-extensive with intestine; transverse vitelline duct indistinct. Eggs ovoid, with short stumpy polar filament, 9 0 - 1 0 0 X 6 5 - 8 0 p. Vagina funnel-shaped, with ring-shaped sclerotized opening on left body margin at level of shell gland; vaginal duct opening into receptaculum seminis, which is variable in size and lies dorsal or anterior to the ovary according to the state of extension of the body. This species differs from any of the known members of the genus in the structure of the terminal genitalia.

Diplectanum

nenue n. sp.

FIGURE 9 1

Gills of Kyphosus cinerascens (common "nenue"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 6 0 . (Based on 20 whole mounts.) Body elongate, rather slender, 0 . 7 5 - 1 . 0 mm in length, with maximum width of 8 0 - 1 1 0 p at middle third. Opisthohaptor 0 . 1 5 - 0 . 2 mm wide at level of lateral projections; squamodisc 7 5 rows 1 2 5 fi wide, consisting of 2 0 - 3 4 file-like ridges; inner dorsal anchor 3 0 - 4 0 n long from tip of longer ventral root to height of curve of blade; outer ventral anchor 3 0 - 3 8 ¡x long from tip of dorsal root to height of curve of blade; middle bar 1 0 0 - 1 2 5 l° n g; lateral bars slightly swollen at medial end, 4 5 - 6 5 ¡x long; marginal hooklets about 1 2 . 5 ¡x long. Head with very prominent rounded apex, 6 0 - 9 0 ¡x wide at base, with several pairs of lateral head organs. Two pairs of compact eyespots anterodorsal to pharynx. Pharynx 2 7 - 4 3 X 2 2 - 3 8 ¡x; esophagus short; ceca parallel to each other posterior to testis, terminating separately at about middle of posterior third of body. Testis elongate oval, 6 0 - 1 0 0 X 2 5 - 5 0 /x, situated at posterior part of middle third of body. Vas deferens running forward dorsolateral to ovary and forming an elongate seminal vesicle 15-25 ¡x wide on the right of median line just anterior to ovary. This vesicle tapers anteriorly and coming to the left side of the median line leads into the somewhat muscular,

Diplectanidae

DISCUSSION

92 HABITAT

HOLOTYPE DESCRIPTION

119

narrow, winding ejaculatory duct, the distal portion of which is differentiated into the ejaculatory cylinder 6 5 - 9 0 ¡x long by 1 5 - 2 5 wide and provided with very thick wall of longitudinal and circular muscle fibers. Between this ejaculatory cylinder and the cirrus proper is intercalated a small ejaculatory bulb of lamellar muscles, 12-15 ¡x long by 8-10 ¡x wide; cirrus narrow, tubular, heavily sclerotized, directed backward from ejaculatory bulb and enclosed in longitudinally elongated pouch of longitudinal muscle fibers and opening into the genital pore by a ring of circular muscle fibers, the dextral wall of which is produced backward into a sclerotized palmate process projecting into the uterus. Common genital pore 65 p. behind intestinal bifurcation in the type. Ovary oval, 35-55 X 15-35 /*> situated more or less obliquely immediately in front of testis. Shrunken uterine eggs with or without filament at posterior pole, 55-75 X 35-50 ¡x; posterior end of polar filament may be enlarged in form of a cap. Vagina enlarged in form of an oval cavity lined with folded cuticle, opening midventrally immediately behind genital pore; vaginal duct very narrow, sclerotized. Seminal receptacle immediately posterodorsal to vagina. Vitellaria co-extensive with intestine. This species resembles Diplectanum diplobulbus n. sp. very closely, especially in the structure of the ejaculatory cylinder and the ejaculatory bulb, but differs from it distinctly in the cirrus possessing a powerful muscle ring from the lateral wall of which arises a well sclerotized, backwardly directed palmate process.

Diplectanum opdkapaha n. sp.

FIGURE 9 2

Gills of Pristipomoides microlepis (type host, local name "opakapaka") and Aphareus ruffians; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 161. (Based on 2 6 whole mounts.) Body elongate fusiform, 0 . 8 - 1 . 4 M M L° N §> up to 0 . 1 4 - 0 . 2 4 mm wide at level of testis. Opisthohaptor 0 . 1 4 - 0 . 1 8 mm wide, well constricted off from body proper, with two pairs of basally bifid anchors and three separate bars; dorsal anchor 4 9 - 7 0 n long from tip of dorsal root to height of curve of blade; ventral anchor 5 8 - 7 0 ¡x long from tip of dorsal root to height of curve of blade, with almost equally long roots; ventral median bar tapering laterally, 6 5 - 1 0 9 ¡x long; submedian bars somewhat swollen at medial end, 4 9 - 7 5 ¡x long. Squamodisc consisting of mostly incomplete circles of amboss-like denticles followed by arcuate rows of irregularly disposed spiniform denticles. Head trapezoidal, 6 0 - 1 4 0 ¡X wide. Two pairs of eyespots dorsal to anterior half of pharynx. Pharynx 3 7 - 7 0 X 2 7 - 5 3 fc esophagus very short, may be up to 6 0 ¡x; ceca simple, terminating separately at about middle of posterior third of body. Testis elongate oval, 1 5 0 - 2 5 0 X 6 0 - 1 2 5 ¡x, in middle third of body. Vas deferens markedly swollen in its ascending course, forming seminal vesicle immediately behind intestinal bifurcation; ejaculatory duct very narrow,

120

DISCUSSION

93 HABITAT HOLOTYPE DESCRIPTION

arising from anterior end of seminal vesicle. Cirrus tubular, very long, coiled upon itself three or four times, without accessory piece. Prostatic reservoir to left of seminal vesicle; its efferent duct running backward alongside ejaculatory duct. Genital pore shortly postbifurcal. Ovary looping around right cecum, with its swollen proximal end (2063 ¡x wide) immediately in front of testis, giving rise to germiduct at its left anterior end. No eggs observed. Vagina fusiform to subcylindrical, extending obliquely backward from its opening which lies ventral or medial to the left cecum. Vaginal duct narrow, arising from proximal end of vagina where a small sphincter is seen, running backward and joining seminal receptacle. Shell gland situated mostly to left of main proximal portion of ovary. This species can be distinguished easily from any of tiic known members of the genus by its coiled cirrus. The specific name refers to the local name for the host.

Diplectanum priacanthi n. sp.

FIGURE 9 3

Gills of Priacatithus boops; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 6 2 . (Based on seven whole mounts.) Body elongate, 0 . 6 6 - 0 . 9 mm in length, with maximum width of 0 . 1 2 - 0 . 2 3 mm in region of middle third. Opisthohaptor 1 1 5 - 2 0 0 ju wide; squamodisc circular, 4 5 - 7 0 ¡x in diameter, with 8-10 complete circles of minute trapezoid scales; median bar strongly constricted at middle, 4 6 - 7 0 ju, long; submedian bar enlarged at medial end, 4 6 - 5 8 ¡x long; dorsal anchor 51—58 ¡x long lineally, with two roots equal in length; ventral anchor 46-51 ¡x long lineally from tip of longer dorsal root to height of curve of blade. Head blunt-conical, 6 0 - 9 0 ¡x wide, with head organs along sloping sides. No eyespots. Pharynx pyriform, 3 5 - 4 6 X 3 0 46 f1; ceca simple, terminating blindly at posterior end of body proper. Testis elliptical, 9 0 - 1 6 5 X 4 5 - 8 1 ¡x, largely at equatorial level. Vas deferens up to 11-25 P wide, twisted in uterine zone medial to left cecum. Cirrus consisting of a very narrow spicule enclosed in cylindrical sheath of oblique or longitudinal fibers. Common genital pore shortly postbifurcal, a little to left of median line. Prostatic cells massed together on each side of uterus and vas deferens posterior to cirrus; prostatic reservoir fusiform, connected with base of cirrus by a small muscular bulb. Ovary retort-shaped, 2 3 - 3 5 wide, immediately anterodextral to testis, with its attenuated distal portion embracing right cecum. Shell gland well developed at level of anterior end of ovary. Uterus curved as the contained egg is bent at junction with its posterior filament; one egg at a time, somewhat wrinkled longitudinally, 9 7 - 1 1 6 X 3 9 - 4 6 ¡x in mounted condition; posterior filament swollen into an elongate robust body 3 7 - 4 6 ¡x long by 10-14 P wide- Vitellaria co-extensive with intestine, confluent in posttesticular area. Vagina narrow, tubular, nearly straight, 3 2 - 5 8 ¡x long, consisting of inner cuticle and outer circular muscles, opening ventral to left cecum

Diplectanidae

DISCUSSION

94 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

95 HABITAT HOLOTYPE

121

a little behind genital pore; vaginal duct very narrow, running obliquely backward. Seminal receptacle oval, 25 X 16 ¡x, at proximal end of vaginal duct. This species is characterized by the sheathed spicular cirrus and the simple tubular vagina. In the character of the squamodisc it resembles Diplectanum curvivagina (see above), but in the latter species the cirrus is entirely different and the vagina is curved and distinctly enlarged toward the distal end.

Diplectanum

querni n. sp.

FIGURE 9 4

Gills of Epinephelus quernus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 163. (Based on 10 whole mounts.) Body approximately fusiform, 0.45-0.7 mm long, up to 0.12-0.14 mm wide in midregion. Opisthohaptor 0.14-0.2 mm wide, sharply marked off from body proper; squamodisc about 50 ¡x in transverse diameter in the type, consisting of about ten, mostly open, circles of scale-like ridges. Two pairs of anchors bifid at base, dorsal 32-40 ¡x, ventral 25-38 ¡x long; median bar tapered at each end, 65-80 ¡x long; submedian bars swollen at inner end, 50-63 ¡x long; marginal hooklets 7.510 ft long. Head trapezoidal, 40-58 ¡1 wide at base, with several head organs along each sloping lateral margin. Two prepharyngeal pairs of eyespots present. Pharynx globular, 18-25 f- * n diameter; ceca terminating separately behind testis. Testis elliptical, 50-75 X 18-50 ¡x, at posterior end of middle third of body. Vas deferens ascending in median field, forming seminal vesicle before becoming convoluted. Ejaculatory duct straight distally, provided with longitudinal muscle fibers, opening into 4-chambered basal bulb of cirrus along with prostatic reservoir which is 30 ¡x by 25 ¡x in the type and lies to the right of the cirrus bulb. Cirrus consisting of curved 4-chambered a curved distal spicule. Genital pore basal bulb 17-55 x 27~~43 /* median, 50 ¡x behind intestinal bifurcation in the type 0.45 mm long. Ovary swollen at base up to 18-40 ¡x wide, immediately anterodextral to testis, with its tapering distal portion embracing right cecum. Uterus ventromedian; eggs collapsed in uterus, about 70 ¡x long. Vagina tubular, a little widened distally (up to 10 ju), opening in left subedian line immediately behind cirrus; vaginal duct forming two small loops or swellings (?) near vagina. Seminal receptacle present. Vitellaria co-extensive with intestine. This species very closely resembles Diplectanum serrani Yamaguti, 1953 from Serranus sp. of Celebes in internal anatomy but differs from the latter in possessing a distinct muscular pars ejaculatoria.

Diplectanum

spiculare n. sp.

Gills of Kyphsus cinerascens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No.

FIGURE 9 5

164.

122

DESCRIPTION

DISCUSSION

KEY TO SPECIES OF

Diplectanum FROM HAWAIIAN FISHES

(Based on 1 1 whole mounts.) Body elongate, markedly attenuated anterior to opisthohaptor, 0.7-1.0 mm in length, 0.1-0.16 mm in maximum width in anterior half. Opisthohaptor 100-130 fx. wide; squamodisc 170200 /j. wide, with 40-50 rows of file-like ridges; outer dorsal anchor stout, broad-based, right-angled, 57-75 ¡j- long from tip of blade to base; ventral anchor slender, Y-shaped, 50-65 ¡x long from tip of longer root to height of curve of blade; middle bar 155-183 ¡j. long, swollen medial to curved lateral end; lateral bar angularly enlarged at each end, 62-80 /x long; marginal hooklets 10 p. long. Head with very prominent rounded apex, 70100 ¡x wide at base, with several pairs of head organs. Two pairs of compact eyespots immediately anterior to pharynx. Pharynx 27-50 X 27-38 /»; esophagus short; ceca simple, terminating separately at attenuated part of body. Testis oval to elliptical, 50-88 x 25-43 fi, in midregion of body. Vas deferens forming conspicuous seminal vesicle up to 30 ¡i wide anterior to ovary. Cirrus consisting of basally bulbous, cylindrical, inverted sheath 5770 ¡i long and a very fine tubular spicule projecting beyond tip of sheath which is prolonged ventrally or laterally into a spiniform barb. Genital pore median, at junction of middle with posterior third of body. Ovary oval, 37-70 X 25-50 ¡i, situated a little obliquely in front of testis, may more or less overlap latter. Shell gland complex conspicuous. Shrunken uterine eggs constricted into two portions. Vagina reduced to a narrow tubule 15 ¡i long, opening ventrally to left of median line about 40 fi behind genital pore in the type; vaginal duct swollen distally; seminal receptacle present. Vitellaria co-extensive with intestine. This species is characterized by the cirrus being a very fine spicule enclosed in the cylindrical sheath and directed from in front backward. Squamodisc split posteriorly: 2 Squamodisc not split posteriorly: 4 Ejaculatory bulb bipartite: 3 Ejaculatory bulb absent; cirrus proper spicular, with non-muscular sheath; vagina reduced to a short narrow tubule: D. spiculare Copulatory organ provided with muscular ring, from one side of which arises palmate cirrus proper; vagina represented by enlarged D. nenue cavity lined with folded cuticle: Copulatory organ consisting of a simple plug-shaped cirrus with heavily sclerotized lining; vagina small, simple: D. diplobulbus Squamodisc completely or almost completely closed: 5 Squamodisc largely consisting of transverse or semicircular rows of scale ridges: 6 Cirrus approximately C-shaped; vagina comma-shaped: D. curvivagina Cirrus spicular, enclosed in cylindrical muscular sheath; vagina tubular, straight: D. priacanthi Ejaculatoiy duct transversely striated throughout with muscle fibers, folded back on itself; cirrus with complex accessory pieces; vagina funnel-shaped, marginal: D. kuhliae Ejaculatory duct narrow, non-muscular; cirrus tubular, coiled

Diplectanidae

123

back on itself, without accessory piece; vagina narrow, fusiform or subcylindrical, submedian: D. opakapaka Ejaculatory duct longitudinally striated with musclefibersat distal portion alone; cirrus with large 4-chambered base; vagina enlarged at opening, submedian; vaginal duct looped or swollen (?) distally: D. quemi

96 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

Lamellodiscus epsilon n. sp.

FIGURE 9 6

Gills of Monotaxis sp. (M. grandoculis ?); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 6 5 . (Based on 1 7 whole mounts.) Body rather slender, subcylindrical, 0 . 8 1 . 2 mm long, 8 0 - 1 2 0 ¡x wide in midregion. Opisthohaptor laterally elongated, 1 8 0 - 2 5 0 fi, wide at level of posterolateral^ directed projections, slightly constricted in pirehaptoral region where the dorsal and ventral squamodiscs are located; outer dorsal anchor 4 0 - 5 3 ¡x long from tip of base to height of curve of blade, its base not distinctly divided into two roots; inner ventral anchor with distinctly bifid root, 5 0 - 6 3 ¡x long from tip of longer dorsal root to height of curve of blade; median bar tapered laterally, 8 0 - 1 1 3 P l o n 8; lateral bar arcuate, 6 5 - 8 0 ¡x long; marginal hooklets about 10 fx long, well recognizable at tip of lateral lobe and on each lateral margin of body at level of squamodiscs, each with papillate base. Squamodisc elliptical, 8 0 - 1 2 0 x 5 5 - 7 5 n, consisting of ten lamellae, of which the apical one is complete and reniform, but all the others are rib-like and paired, meeting in the median line. Head prominently trapezoidal, 4 0 - 1 0 0 ¡x wide at base, with several pairs of head organs. Two pairs of compact eyespots anterodorsal to pharynx. Pharynx 2 5 - 3 5 X 2 2 - 3 0 ¡x; esophagus short; ceca terminating separately shortly anterior to squamodiscs. Testis elliptical, 9 0 - 1 5 1 X 3 2 - 7 5 ¡x, confined to middle third of body. Vas deferens looped proximally and dilated in form of tubular seminal vesicle medial to right cecum, then turning back on itself sinistrodorsal to cirrus and opening into base of cirrus. Cirrus E-shaped, with one prong tricuspid at tip and others simple, rounded at base, 2 0 - 4 0 X 12-25 /*» se P a " rated from intestinal bifurcation by inverted, pyriform, anterior, prostatic reservoir 12.5 ¡x wide in the type. Elongate, posterior, prostatic reservoir obscured by vitellaria between right cecum and tubular seminal vesicle; its efferent duct, however, is clearly seen opening into base of cirrus from behind. Genital pore midventral, a little postbifurcal. Ovary 2 5 - 3 7 P- l°ng> looping around right cecum just anterior to testis. Shrunken uterine eggs elongate oval, 7 0 - 9 8 X 3 5 - 4 4 ¡x, with a short rigid filament 4 5 - 6 3 ¡x long. Vagina thin-walled, provided inside with a circle of several sclerotized denticles, opening ventrally to left of median line shortly behind base of cirrus; vaginal duct narrow, running obliquely backward to join germiduct at level of transverse vitelline duct. No seminal receptacle. Vitellaria profusely developed along intestinal limbs. This species differs from the most closely related Lamellodiscus flexuosus

124

Yamaguti, 1953 in the cirrus' being trifúrcate anteriorly in the form of an E , to which the specific name refers.

97

HABITAT

HOLOTYPE DESCRIPTION

Acleotrema

kyphosi

n. sp.

FIGURE 9 7

Gills of Kypfiosus cinerascens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 166. (Based on 39 whole mounts.) Body subcylindrical, 0.8-1.65 X 0.1-0.22 mm, tapered and spinose posteriorly. 1 Opisthohaptor well marked off from body proper, 0.16-0.28 mm wide, with a prominent dorsal and a ventral squamodisc 130-200 ix wide and consisting of 20-50 concentric rows of denticulate scales; median bar 115-233 ¡x long; lateral bar 50-83 ¡x long; dorsal anchor 40-65 f- l ° n g lineally from tip to anterior end of truncate base; ventral anchor with bifid root, 45-65 ¡x long from tip of longer dorsal root to height of curve of blade; marginal hooklets at lateral corner 7 - 8 ¡x long. Head approximately triangular, rounded at apex, 0.08-0.17 mm wide at base, with numerous head organs along lateral slopes. Two pairs of eyespots present. Pharynx globular, 32-62 X 30-60 ¡x, with masses of head gland cells on each side; esophagus very short; ceca simple, extending separately into posterior third of body. Testis oval, 1 1 2 - 2 0 0 X 3 5 - 1 2 5 p, nearly equatorial. Vas deferens distended with sperm, winding forward ventral to ovary in left intercecal field, without forming a definite seminal vesicle. Cirrus C-shaped, hollow, with its tip turned back on itself and continued into markedly attenuated, often recurved tubule, its total length 5 5 - 1 2 5 //. lineally, varying in accordance with the degree of bending of the terminal tubule; the base of the cirrus is enclosed in a muscular bulb consisting of inner radial muscle bundles and outer capsule of longitudinal muscle fibers, latter capsule produced backward, enclosing proximal portion of cirrus. At about the junction of anterior two thirds of body is a large genital atrium opening ventrally by a large, irregularly incised pore a little to the right of the median line; a large, backwardly directed, curved process (50-70 ¡x long), convex surface of which is covered with heavy cuticle, projects from the right wall of the genital atrium; the convex edge of the process is provided with a row of saw-teeth, and the pointed end of the process shows at the posterior end of the genital pore opposite the thickened muscular wall of the genital atrium. Immediately behind this muscular thickening of the genital atrium is transverse depression of the body surface. A small saccular prostatic reservoir lies on the left side of the copulatory organ. Ovary retort-shaped, 50-125 X 2 0 - 1 1 2 ¡x, immediately anterior to testis, often partly overlapping latter. Shell gland complex preovarian. Uterine eggs more or less shrunken, 60-78 X 35-50 ¡x, without filament. Vagina not Spines not visible in the type, probably owing to post-mortem desquamation.

Diclidophoridae

DISCUSSION

Order Superfamily Family Subfamily 98 HABITAT HOLOTYPE DESCRIPTION

125

observed. Seminal receptacle in front of shell gland. Vitellaria co-extensive with intestine. This species is characterized by the peculiar structure of the copulatory apparatus and the wide genital atrium which is provided laterally with a curved process with serrate edge. The description and illustrations given by Johnston and Tiegs ( 1 9 2 2 ) for Acleotrema girellae include two different species, as is evident from comparison of the terminal genitalia from a young worm with those from an adult worm. In the figure of the adult, they show the cirrus as opening into the ventral "genital cavity," the uterus as opening beside the cirrus sac, and the vagina as opening into the "genital cavity" near the male pore. From the marked difference between A. girellae of Johnston and Tiegs and the other members of diplectanids, it seems certain that there are some serious errors in the observation by the Australian authors of this species, not to speak of their confusion of two different species.

POLYOPISTHOCOTYLEA Odhner, 1912 DICLIDOPHOROIDEA Price, 1936 DICLIDOPHORIDAE Cerfontaine, 1895 GEMPYLITREMATINAE n. subf. Gempylitrema

longipedunculatum

n. g., n. sp.1

FIGURE 9 8

Gills of Promethichthys [Gempylus] prometheus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 167. (Based on five whole mounts.) Body 6.5-10 mm in length including opisthohaptor, with maximum width of 0.7-1.1 mm at about one third of body length from anterior extremity. From this region the body tapers abruptly forward, but gradually backward to form a long, markedly attenuated peduncle for the opisthohaptor. Opisthohaptor membranous, 0.51.5 mm long, provided with four pairs of short-stalked clamps. Clamp skeleton 0.11-0.16 mm in transverse diameter, consisting of two pairs of lateral sclerites, a T-shaped median spring, the two incurved arms of which are jointed with the shorter lateral sclerites, an unpaired basal piece directed inwards, and an unpaired basal ring, the narrower undulating ventral portion of which articulates with the simple base of the median spring. The larger lateral sclerites are continuous across the median spring ventrally at the apex. Head truncate, 0.24-0.35 mm in diameter, with unusually wide terminal mouth aperture along the margin of which are numerous dots, probably representing glandular cells. Prohaptoral suckers 1

The generic name refers to the family to which the host belongs. The specific name refers to the long stalk of the opisthohaptor.

126

DISCUSSION

side by side, projecting forward into mouth cavity, 0.11-0.2 X 0.080.15 mm, each consisting of two basally fused, non-muscular, well sclerotized valves of unequal length and dissimilar shape; the ventral valve has a conspicuous apical notch, into which shuts down the ventral nodular thickening at the apical end of the dorsal valve; the lateral slit-like opening of each sucker reaches to near the fused base of the two valves. Pharynx elliptical, 60-90 X 50-70 ¡x, devoid of distinct muscular element. Esophagus simple, short, provided anteriorly with scattered pigment cells similar to those accompanying the intestinal wall, bifurcating immediately in front of genital pore. Intestinal limbs with numerous ramified branches, terminating at about midregion of body. Testes oval or irregular in outline, 10-15 number, situated in a zigzag row or two longitudinal rows in interintestinal field between ovary and cecal ends. Vas deferens only slightly winding in median field. Neither distinct ejaculatory duct nor cirrus differentiated. A round muscular genital atrium provided with a crown of 1 1 - 1 2 sharp hooks which are curved inwards near the base. Genital pore immediately postbifurcal. Ovary tubular, folded back on itself several times, measuring 0.4-2.0 X 0.2-0.3 mm as a whole, situated at about anterior end of middle third of body, with its distal end directed backward. Germiduct descending, giving off genito-intestinal duct just before joining stem of vitelline reservoir, and after continuing a short descending course it turns back on itself to lead into uterine duct; compact shell gland cells massed together around this bending point. Uterus midventral, containing no eggs. Genito-intestinal duct opening into right intestinal limb a little posterior to origin of germiduct. No seminal receptacle. Vitellaria profusely developed not only in lateral fields but also in anterior median field both dorsally and ventrally, from behind level of genital pore to beginning of haptoral peduncle, completely enclosing intestinal branches. Vitelline reservoir Y-shaped, bifurcating at level of anterior end of ovary, with its stem overlapping ovary. Vaginae rudimentary, opening symmetrically on lateral margins of body a short distance (ca. 0.2 mm in the type) posterior to genital pore. This obviously diclidophorid genus differs from any other known genera of Diclidophoridae, except Tagia gempylli [sic] Dillon et Hargis, 1965, in the structure of the haptoral clamps and the oral sucker. The most outstanding features are: (1) opisthohaptor with a very long peduncle; (2) haptoral clamps asymmetrical basally, but symmetrical apically, with T-shaped median sclerite; and (3) oral sucker non-muscular and bivalved. In general internal anatomy, especially in the arrangement of the testes and the structure of the ovarian complex and terminal genitalia, the present species resembles T. gempylli Dillon et Hargis, 1965, but it differs in the structure of the oral sucker and in the number of the testes and of the genital coronet. T. gempylli D. et H., 1965 undoubtedly belongs to the same genus as the present genus, although Dillon and Hargis state that in their species the oral sucker is cylindrical and muscular. In the present species the oral sucker is bivalved and definitely non-muscular; there are neither "extra

Pseudodiclidophoridae

127

center sclerites" nor "numerous short sclerites located in the valve wall [of the clamp]" as mentioned by Dillon and Hargis. These differences are, I believe, due to difference in observations. I venture to propose a new subfamily Gempylitrematinae, with the present genus as type, on the basis of the above mentioned characteristics.

GEMPYLITREMATINAE SUBFAMILY DIAGNOSIS

TYPE GENUS

n. subf.

Diclidophoridae. Opisthohaptor terminal, symmetrical, with long attenuated peduncle and four pairs of equal-sized, subsessile clamps, the skeleton of which is symmetrical apically but asymmetrical basally, without suckerlike structure at base. Oral suckers paired, each consisting of two, basally fused, well sclerotized, non-muscular valves; pharynx non-muscular; esophagus simple; intestinal limbs ramified, not uniting posteriorly. Testes postovarian, more or less numerous. Genital bulb with coronet of hooks. Genital pore ventral to, or immediately posterior to, intestinal bifurcation. Ovary tubular, winding, pretesticular. Genito-intestinal duct present. No seminal receptacle. Eggs? Vaginae rudimentary, opening symmetrically on lateral margins of body. Vitellaria co-extensive with intestinal branches, not intruding into haptoral peduncle; vitelline reservoir Y-shaped, with its stem in ovarian region. Gill parasites of marine teleosts. GempylitTema n. g.

Gempylitrema n. g. GENERIC DIAGNOSIS TYPE SPECIES OTHER SPECIES

Family Subfamily 99 HABITAT HOLOTYPE DESCRIPTION

Diclidophoridae, Gempylitrematinae, with characters of subfamily given above. G. longipedunculatum n. sp. (v. s.) G. gempylli (Dillon et Hargis, 1 9 6 5 ) n. comb., syn. Tagia gempylli1D. et H., 1965, in Rexea solandri; New Zealand.

PSEUDODICLIDOPHORIDAE PSEUDODICLIDOPHORINAE

Yamaguti,

Yamaguti,

1965

1965

Pseudodiclidophora decapteri Yamaguti, 1965

FIGURE 9 9

Gills of Decapterus pinnulatus (local name "opelu"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 8. (Based on 2 1 whole mounts.) Body 1 . 5 - 2 . 9 mm long, tapering anteriorly L

Should be spelled

gempyli.

128

and rounded posteriorly, 0.35-0.7 mm wide immediately in front of opisthohaptor. Opisthohaptor extending asymmetrically along each posterior lateral margin of body, but separated at the truncate posterior end of body, consisting of 4 pairs of asymmetrically arranged sessile clamps. On the right side the fourth clamp is more or less wider apart from the third than the second is from the first, and on the left side the fourth clamp is separated from the third by a convex body margin 0.17-0.5 mm long; the third clamp is also wider apart from the second just like the third on the right. Clamp skeleton of the right side consisting of a U-shaped median piece, a pair of small basal pieces, two pairs of lateral springs, and a pair of accessory sclerites; median piece widely bifid at end of ventral prong; shorter dorsal prong with U-shaped apical piece, surmounted by accessory sclerites. One of the lateral sclerites is much thinner than its fellow of the same side, almost membranous; the inner lateral sclerites nearly of same thickness. One of the accessory sclerites distinctly longer than its partner. Basal pieces not projecting into lumen of clamp valve. Skeleton of left clamp different from that of right clamp; dorsal prong of U-shaped median piece divided into dissimilar branches, of which the larger articulates with the medial projection from the outer lateral sclerites on one side and also with the larger piece of the X-shaped accessory sclerites on the other; two lateral sclerites of the outer side strongly developed, and denticulated distally on opposite sides, whereas one of those on the inner side is reduced to non-sclerotized piece, though its basal portion is distinctly sclerotized like that of its partner. Head 88-100 ^ wide, with prominent rounded pre-oral lobe. Prohaptoral oral suckers paired as in Microcotyle, aseptate, unarmed, 22-43 x 25—53 Pharynx rounded, 30-43 X 25-43 fx; esophagus simple, often very wide, 0.3-0.7 mm long; ceca with numerous short inner and longer outer branches, confluent at posterior end of body. Testes large, irregular in outline, 15-30 in number, occupying whole postovarian intercecal field. Vas deferens winding forward medial to left intestine in ovarial region, at the anterior end of which it takes the median course. No pars prostatica differentiated. Cirrus represented by a short cylindrical sclerotized structure opening at its tip and measuring 30-3$ P long by 15-23 fx. wide; it lies ventral to semicircle of six longitudinal cuticular rods 38-50 fx long. This coronet, in turn, is enclosed in genital atrium provided with very fine circular muscle fibers. This atrium^ 45-50 X 3047 ¡X, opens midventrally at a distance of 0.16-0.33 mm from head end. Ovary inverted U-shaped, 0.25-0.6 X 0.05-0.16 mm, situated in midregion of body with its proximal end on the right of vitelline reservoir and its distal end near genito-intestinal duct. Uterus ventromedian, apparently opening at common genital pore; eggs 180-220 X 60-90 ¡x, with rigid filament 140-200 ¡x long at each end. Vitellaria co-extensive with intestine and its branches; vitelline reservoir Y-shaped; its stem just postequatorial, 0.1-0.24 m m l°ng> largely overlapping ovary. A pair of elongate saccular seminal receptacles filled with sperm, occasionally also with a mass of yolk

Pseudodiclidophoridae

DISCUSSION

Subfamily

100 HABITAT HOLOTYPE DESCRIPTION

129

cells, connected with arms of vitelline reservoir just medial to intestine, that of the same side as the vas deferens lies between the vas deferens and the intestine of that side. I propose to call this receptacle "receptaculum seminis vitellariorum." Vagina funnel-shaped, symmetrical, marginal, 0.280.6 mm from head end, nearer to genital pore than to intestinal bifurcation; vaginal ducts of two sides joining together in form of V, but no duct communicating with the vitelline reservoir has been detected. This genus apparently belongs to Diclidophoroidea Price, 1 9 3 6 , but it cannot be placed in any known families of this superfamily because of the constant peculiar asymmetry of the opisthohaptor and the presence of symmetrical receptacles connected with the arms of the vitelline reservoir in full-grown specimens. The fact that the vaginal ducts are united and have connection neither with the vitelline reservoir nor with the seminal receptacles is worth noting. For further details of this species as well as the diagnoses of Pseudodiclidophoridae and Pseudodiclidophorinae, see Pacific Science 1 9 ( 1 ) 169-71.

ALLOPSEUDODICLIDOPHORINAE

Yamaguti, 1 9 6 5

Allopseudodiclidophora opelu Yamaguti, 1 9 6 5

FIGURE 1 0 0

Gills of Decapterus pinnulatus (local name "opelu"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 9. (Based on seven whole mounts.) Body markedly attenuated anteriorly, 2 . 9 - 4 . 6 mm in length exclusive of anchor-bearing caudal appendage, with maximum width of 0 . 9 6 - 1 . 8 mm in testicular region. Opisthohaptor symmetrical, consisting of four pairs of small sessile clamps about 10 n in diameter, extending along posterior margin of body, with base of caudal appendage between. Clamp skeleton similar to that of Pseudodiclidophora decapteri with A-shaped accessory piece; left dorsal sclerite slender and jointed, whereas right ventral sclerites slender and unjointed, so that the lateral sclerites are asymmetrical; median spring bifid at both ends, dorsal prong longer than ventral. Caudal appendage 0 . 5 - 1 . 0 X 0 . 1 - 0 . 1 2 mm, provided at its somewhat swollen distal end with three pairs of hook-shaped anchors; outer anchor 4 5 - 5 0 ¡x long, with very prominent guard; middle anchor similar in shape, 1 8 ¡i long; inner anchor 2 0 - 2 2 p long, also with prominent guard and recurved root. Head rather pointed, about 0.090.12 mm wide. Prohaptoral oral suckers paired, rounded, aseptate, unspined, 3 0 - 4 5 ¡x in diameter. Pharynx bulbous, 35 X 30 ¡x in the type; esophagus 0 . 7 - 1 . 5 mm long, intestinal limb with short inner and longer outer branches, apparently united with each other at posterior end of body proper. Testes transversely elongated, irregular in outline, 12-30 in number, occupying whole postovarian interintestinal field in two longitudinal rows;

130

DISCUSSION

vas deferens middorsal, distended with sperm and may be strongly winding. Cirrus terminating in form of a sclerotized cylinder projecting into genital atrium. This cirrus is supported dorsally by a pair of apically incurved rods 35 ju. long, a pair of also apically incurved lateral rods 4 8 - 5 0 long, and a pair of nearly parallel, apically enlarged, dorsal rods. Genital atrium 5 5 - 6 2 /x long by 4 0 - 5 0 ¡i wide, with wall of circular muscle fibers. Genital pore midventral, 0.25-0.68 mm from head end. Ovary inverted U-shaped, 0.4-0.8 X 0 . 1 5 - 0 . 2 mm, situated at junction of middle with posterior third of body, with both ends directed backwards; genito-intestinal canal crossing distal end of ovary and opening into right intestinal limb. One uterine egg observed, 0.17 X 0.07 mm, with rigid filament 0.16 mm long at one pole and another 0.2 mm long at the other pole. Vitellaria co-extensive with intestinal branches; vitelline reservoir Y-shaped, nearly midventral; its arms widely divergent, each connected with seminal receptacle of its own side. Paired seminal receptacles elongate fusiform, 0.2-0.43 mm long, containing abundant yolk cells and sperm, situated one on each side of ovary at level of junction of middle with posterior third of body. Vaginae symmetrical, funnel-shaped at base, opening ventrolaterally by a small round pore at a distance of 0 . 4 - 1 . 2 mm from head end; vaginal duct arising from bottom of vaginal funnel, running medioposteriad to unite with its fellow of the other side, resulting unpaired median duct apparently emptying into vitelline reservoir at junction of its two arms. It is worth noting that sperm are seen scattered in various parts of the vitelline ducts. Although this genus differs markedly from Pseudodiclidophora (loc. cit.) in general body shape, it agrees completely with the latter in the most important characters, such as clamp structure and internal anatomy, and particularly in possessing paired receptaculum seminis vitellariorum. The presence of a long anchor-bearing caudal appendage, however, prevents its being assigned to the same genus. I would rather consider this character combined with the symmetrical arrangement of the opisthohaptoral clamps to be of subfamily importance; hence a new subfamily Allopseudodiclidophorinae was proposed. For further details of this species and the diagnoses of the genus and the new subfamily, see Pacific Science 19(1)71-74.

Family Subfamily 101 HABITAT HOLOTYPE DESCRIPTION

DISCOCOTYLIDAE Price, 1936 ALLODISCOCOTYLINAE Tripathi, 1959 Allodiscocotyla lae n. sp.

FIGURE 1 0 1

Gill of Scomberoides sancti-petri (local name "lae"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 168. (Based on 25 whole mounts.) Body slender, 1 . 8 - 3 . 1 mm in length, with

Discocotylidae

131

maximum width of 0.18-0.4 mm in midregion, whence it tapers anteriorly to a conical point. Opisthohaptor separated from body proper by a markedly attenuated isthmus portion; clamp skeleton 30-60 /t in transverse diameter; longer prong of median spring anchor-shaped at tip, whereas the shorter prong terminates in paired wings at the tip; clamp capsule with distinct transverse, partly oblique, rib-like markings. Caudal hooks of outer pair with prominent guard and a long claw-like blade, 30-40 ft long from tip of simple root to height of curve of blade; those of inner pair usually rudimentary, obsolete, occasionally well developed, similar in shape to outer pair, about one-sixth as long as outer. Head 70-130 p. wide, with wide mouth aperture ventrally; paired oral suckers oval, 1 7 38 X 27-53 with inconspicuous partition at middle. Pharynx small, rounded, 1 5 - 3 0 X 1 5 - 2 8 fi; esophagus apparently without outgrowths, bifurcating at level of posterior end of vagina. Intestinal limbs with numerous short side branches, terminating parallel to each other at base of cotylophore. Testes round, 10-26 in number, arranged in front of ovary in two longitudinal rows and in one longitudinal row to left of ovary in interintestinal field of middle third of body; only a few follicles may be present behind the ovary. Vas deferens winding irregularly between two longitudinal rows of testes; seminal vesicle elongate, tubular, 25-43 /* wide; pars prostatica not well differentiated, 0.2-0.6 mm long lineally, spirally winding in median field between seminal vesicle and cirrus pouch, surrounded by rounded prostate cells throughout its length. Cirrus pouch subcylindrical, ventral to esophagus, 125-300 X 30-55 p, provided with well developed longitudinal and circular muscles, enclosing a short ejaculatory duct and a densely spined cirrus 100-175 l ° n g by 17-40 ¡¡. wide; cirrus spines very fine, rosethom-shaped, but rather acicular posteriorly, up to 12 ju long. Genital pore midventral, 150-375 ¡x from head end. Ovary greatly elongated longitudinally, folded upon itself on right side of median line at posterior part of middle third of body, with its proximal end posterior to distal end. In the type the germiduct arising from the distal end of the ovary describes a sigmoid curve near its origin and widens only slightly just before giving off the genito-intestinal duct, but narrows markedly after giving rise to this duct and soon unites with the tapering end of the vitelline reservoir; it continues its backward course for a short distance (60 ¡i) and then turns back on itself. The genitointestinal duct is very narrow and long and joins the right intestinal limb near the level of the anterior end of the stem of the vitelline reservoir. Shell gland complex posterior to junction of germiduct with vitelline reservoir. Uterus midventral; uterine eggs fusiform, 160-190 X 50-60 ¡x in mounted condition; posterior polar filament rigid, gradually tapered, up to 100-163 ju long. Vagina retort-shaped, often constricted into two portions, 115-200 X 30-60 ¡x, opening on right margin at about middle of anterior third of body. It is lined with cuticle and provided with rather weakly developed longitudinal muscles; vaginal duct proper nar-

132

DISCUSSION

Subfamily

102 HABITAT HOLOTYPE DESCRIPTION

row, arising well apart from posterior end of vagina and running backward alongside vagina; it divides in the median line dorsal to the pars prostatica a little behind the level of the posterior end of the vagina into three ducts distended with sperm, of which two communicate with the left vitelline duct and the other with the right vitelline duct as shown in the figure. Vitellaria largely coextensive with intestinal limbs; vitelline reservoir Y-shaped, its stem 0.13-0.3 mm long, immediately sinistral to ovary. This species differs from Allodiscocotyla chorinemi Yamaguti, 1953 in the testes extending further backward and also in the communication of the vaginal duct. The specific name refers to the local name of the host.

OPISTHOGYNINAE Unnithan, 1962

Pseudopisthogyne

lepidocybii Yamaguti, 1965

FIGURE 102

Gills of Lepidocybium flavobrunneum; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 10. (Based on seven whole mounts.) Body elongate, rather slender, gradually tapering anteriorly, 4.3-13.5 mm in total length including slender, hookbearing caudal appendage which arises from the extreme posterior end of the body proper nearer to the small posterior-most clamp than to large posterior-most clamp, and measures 0.4-1.4 mm long and 0.07-0.18 mm wide at the slightly enlarged, truncate tip. Of the three pairs of anchors the largest outer is 51-64 /i long from end of short root to height of curve of blade, with prominent guard curved toward the blade, the middle 18-26 jj. long, with its incurved guard well apart from tip of root; the inner 27-31 ¡1. long; its guard, to which many muscle bundles are convergently attached, is directed straight toward the tip of the blade. Opisthohaptor asymmetrical, with four pairs of clamps, 0.34-0.9 mm long on the right (pore) side, 0.7-2.5 mm long on the left; right clamps distinctly pedunculate, left ones subsessile; skeleton of right clamp 90-160 p in diameter, symmetrical, or only slightly asymmetrical because of different curvature of the lateral sclerites, consisting of median spring with bifid ends, a pair of accessory sclerites, two pairs of unjointed lateral arms, and a pair of short basal sclerites; skeleton of left clamp 150-330 P. wide, consisting of two asymmetrical unjointed lateral arms, a median spring with bifid ends, a pair of accessory sclerites, and a pair of basal sclerites; capsule of clamp strongly muscular; proximal outer quadrant distinctly larger than proximal inner quadrant, bulging out at base, thus causing asymmetry of lateral sclerites; two lateral sclerites of proximal outer quadrant showing gentle sigmoid curve in strong contrast with opposite sclerites which are simply arcuate. Head blunt-pointed, 0.170.28 mm wide at level of oral aperture, with a pair of well developed

Discocotylidae

133

apical organs. Intrabuccal sucker elliptical, muscular, with a partition at middle, 50-90 X 70-140 Pharynx subglobular, cellular, 40-80 X 40-70 ¡i; m m esophagus 0.22-0.63 l°ng> simple except at its diverticulate posterior portion, bifurcating at level of vagina. Intestinal limbs with numerous subdivided outer branches, terminating close to each other at base of caudal appendage. Testes rounded, 90-170 in number, arranged in one layer, occupying whole interintestinal field of posterior part of anterior third and entire middle third of body. Vas deferens winding between two rows of anterior-most testes and also in pretesticular interintestinal field where there are numerous gland cells surrounding the duct. Whether these gland cells are prostatic in nature is not certain. After passing dorsal to the vaginal pore it forms a somewhat muscular sigmoid duct and leads into slightly winding pars prostatica 0.2-0.5 mm long and provided with circular muscle fibers and a coat of prostatic cells; ejaculatory duct sigmoid, 0.1-0.22 mm long, with a very thick coat of circular muscle fibers, with its anterior end usually turned back on itself to lead into cirrus pouch. Latter cylindrical, 0.12-0.26 mm long by 30-55 ¡t. wide, with longitudinal muscles, projecting into genital atrium which consists mainly of circular muscle fibers. Immediately outside this genital atrium and cirrus pouch there is a thick coat of accompanying cells. Common genital pore on sinistroventral margin of body 0.35-0.8 mm from head end.

DISCUSSION

Ovary 0.5-1.15 X 0.08-0.22 mm, occupying interintestinal field at anterior half of caudal third of body, consisting of multilobed proximal end situated posteriorly, a narrow tubular portion ascending medial to right intestinal limb, and a looped main portion situated anteriorly with distal end directed posteriad. Genito-intestinal duct given off just before the germiduct joins the vitelline reservoir. Uterus midventral, running alongside muscular ejaculatory duct and cirrus pouch and opening into genital atrium. Eggs fusiform, 0.2-0.21 mm long, with rather rigid bipolar filament 0.18-0.28 mm long. Vagina provided with sphincter-like circular muscles, with wide midventral opening at a distance of 0.8-1.9 m m f r o m head end. Accessory vaginal ducts arising sideways, one on each side of vagina, each provided with sphincter-like circular muscle fibers at the point where it turns backward to join the transverse commissure between anastomosing anterior-most vitelline ducts of two sides; median vaginal duct proper arising from middle of base of vagina traceable some distance back of vagina, but its posterior termination not determined. Vitellaria co-extensive with intestine; vitelline reservoir Y-shaped, with long stem coinciding with ovarian zone. This genus agrees closely with Opisthogyne Unnithan, 1962 in general anatomy, but it differs in several important characters such as: (1) oblique body ridges, as observed in Opisthogyne and Gemmacaputia, are entirely absent; (2) marked asymmetry of opisthohaptor; (3) subsessile clamps with asymmetrical lateral sclerites due to unequal development of capsule of one proximal quadrant, whereas pedunculate clamps are

134

symmetrical in skeleton; (4) ovarian complex shifted far backward by enormous number of testes; and (5) vaginal pore midventral instead of middorsal. These differences, especially the asymmetrical opisthohaptor, the asymmetrical skeleton of subsessile clamps, and the absence of oblique body ridges, are sufficient to justify the erection of a separate genus, for which Pseudopisthogyne was suggested in recognition of its marked resemblance to Opisthogyne Unnithan, 1962. In Opisthogyne, Unnithan states that the vaginal duct opens into the ootype, but this is obviously an error. For further details, see Pacific Science 19(1):74-76.

103 HABITAT HOLOTYPE DESCRIPTION

Allopseudopisthogyne

constricta Yamaguti,

1965

FIGURE 1 0 3

Gill of Lepidocybium flavobrunneum; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 11. (Based on 20 whole mounts.) Body elongate, 7 . 6 - 1 6 . 5 mm long by 0 . 8 - 1 . 6 mm wide, gently curved in widest testicular region to the left, but to the right posterior to region of body constriction which usually occurs behind the midregion of the body. Opisthohaptor asymmetrical, with four larger subsessile clamps on pore side and four smaller pedunculate clamps on the other side. Skeleton of small clamps 9 0 - 1 3 0 ¡x wide, consisting of two pairs of symmetrical lateral sclerites, a pair of accessory sclerites, a pair of basal sclerites, and a median spring with anchor-shaped tip for longer prong and V-shaped wing-like apical piece for bifid end of shorter fenestrated prong. Skeleton of left larger clamp 1 9 0 - 2 7 0 wide, consisting of two pairs of asymmetrical lateral sclerites, a pair of accessory sclerites, a pair of basal sclerites, and a median spring with anchor-shaped tip for longer prong and V-shaped apical piece for bifid end of shorter fenestrated prong; proximal outer quadrant of clamp capsule a little larger than corresponding inner quadrant, thus causing asymmetry of lateral and basal sclerites which is, however, not so pronounced as in Pseudopisthogyne, in which the two lateral sclerites of the proximal outer quadrant show a gentle sigmoid curve. At the extreme posterior end of the body nearer to the small clamp than to the large clamp is a conical appendage 0 . 1 - 0 . 1 7 m m l ° n § an< 3 bearing a pair of hooks close to its rounded or truncate apex; this hook is 4 6 - 5 4 ¡x long from tip of root to height of curve of blade, with a very prominent guard curved toward the blade. Head rounded at apex, 0 . 1 9 - 0 . 4 4 mm wide at level of ventral mouth aperture; apical gland complex present as in Pseudopisthogyne and Pseudopisthogynopsis. Paired oral suckers elliptical, 6 0 - 1 0 0 X 9 0 - 1 4 0 ¡x, with a median septum. Pharynx small, containing cellular element only, 6 0 - 8 0 X 4 0 - 7 0 ju. Esophagus nearly simple anteriorly, but sending posteriorly a number of lateral branches at right angles, bifurcating dorsal to vagina. Intestinal limbs with few simple or ramified side branches and not accompanied by vitellaria in constricted region; in the region of

Discocotylidae

135

the opisthohaptor the side branches are markedly reduced and the limbs run parallel to each other in the median field, being surrounded by vitellaria, and terminate near the base of the hook-bearing caudal appendage. Testes rounded, 120-185 ™ n u m b e r , extending in 2-4 longitudinal rows in interintestinal field from about middle of anterior third to equatorial level far away from ovary and never reaching to it in strong contrast with those of Pseudopisthogyne and Pseudopisthogynopsis. Vas deferens markedly winding between anterior-most testes and intestinal bifurcation, surrounded by prostate-like gland cells; in the region of the vaginal pore it forms a sigmoid muscular canal and leads into the pars prostatica a little anterior to the vaginal pore. Pars prostatica undulating, muscular, median, 0.16-0.5 mm long, surrounded throughout its length by numerous prostate cells. Ejaculatory duct cylindrical, 0.16-0.25 mm long, up to 50 ¡x wide, provided with a thick layer of circular muscles, usually with its anterior end turned back on itself before leading into cirrus. Cirrus simple, narrow, unarmed, enclosed in a cylindrical pouch of longitudinal muscles 0.11-0.23 mm long by 25-50 ¡i wide. Genital atrium consisting mainly of circular muscle fibers and surrounded by numerous accompanying cells, enclosing distal portion of cirrus pouch, cirrus, and uterus. Common genital pore ventrosubmarginal, 0.38-0.7 mm from head end.

DISCUSSION

Ovary 0.9-1.8 X 0.12-0.25 mm, composed of branched proximal lobe situated near posterior end of body proper, a long, tubular, ascending portion, and a winding, looped, distal portion, from the rather straight, descending, terminal portion of which arises the germiduct. Genitointestinal duct opening into right intestinal limb anterior to distal end of ovary. Uterus midventral except for its terminal portion running alongside cirrus pouch. Eggs fusiform, 0.2-0.26 mm long, 60-90 p wide; bipolar filament 0.25-0.32 mm long. Vagina opening midventrally at a distance of 0.82-1.55 mm from head end, provided with a bulb of circular muscles near its comparatively wide, circular aperture; paired accessory vaginal ducts arising sideways from base of vagina, running transversely and then turning backward to join transverse commissure between anastomosing anterior-most vitelline ducts of two sides; median vaginal duct proper can be traced further back of this commissure, but its posterior termination is unknown. Vitellaria commencing in lateral fields at level of vaginal pore, confluent in postovarian region; vitelline reservoir Y-shaped, with its stem between ovary and left intestinal limb. This genus differs from the most closely related Pseudopisthogyne in the body being distinctly constricted posterior to the widest midregion, in the ovary being widely separated from the testes by this constricted area, and in the caudal appendage being reduced to a conical process bearing only one pair of hooks. That the lateral sclerites of the larger clamps do not show a sigmoid curve in contrast with those of Pseudopisthogyne or Pseudopisthogynopsis is also worth noting. For further details, see Pacific Science 19(1):77-78.

136

104 HABITAT HOLOTYPE DESCRIPTION

Metopisthogyne

sphyraenae Yamaguti, 1966

FIGURE

104

Gill of Sphyraena helleri (local name "kawalea"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 48. (Based on five whole mounts.) Body 4.4-8.9 mm long, slender, gradually widened toward opisthohaptor which is 0.8-2.0 mm long by 0.6-1.0 mm wide at base and bears four pairs of short-stalked clamps and a short, trapezoidal, median, caudal appendage provided with three pairs of hooks. Clamp skeleton 0.24-0.3 mm in transverse diameter, consisting of a very stout median spring, a pair of inner basal sclerites, two pairs of arcuate lateral sclerites, and a pair of accessory sclerites; one prong of median spring with three or four minute holes, enlarged at apex in form of a triangle; other prong with anchor-shaped apex, may be bulbously swollen near its base. Of the caudal hooks the larger outermost is 41-46 ¡x long from tip of root to height of curve of blade and has a curved guard a little shorter than root; the smallest middle is 16-18 n long and has a comparatively long root and a short curved blade; the innermost is somewhat similar in shape to the outermost and is 25-28 ¡x long. Head rounded in front, 0.16-0.32 mm wide, with ventral mouth aperture and a pair of groups of gland ducts at apex; paired oral suckers aseptate, muscular, 70-93 x 58-72 n, close together, followed by ovoid nonmuscular pharynx 51-70 /x long by 48-58 ¡1. wide; esophagus 1.0-2.0 mm long, simple, wide, bifurcating just in front of vaginal pore; intestinal limbs with short side branches, terminating separately, one at base of opisthohaptor and the other a little more posteriorly. Testes small, ovoid, 93-162 in total number, extending in interintestinal field from anterior part of middle third of body to anterior half of caudal third, mostly pre-ovarian, partly para- and postovarian. Vas deferens strongly winding in median field between testes and vagina; in the region between the vagina and the pars muscularis there are numerous prostate cells, though the pars prostatica is not distinctly differentiated. Pars muscularis representing ejaculatory duct, 0.35-0.45 mm long by 40-60 ¡x wide, provided with strong transverse or spiral muscle fibers, followed by muscular cirrus 0.18-0.26 mm long which is bulbously swollen near its distal end and projects into the nonmuscular genital atrium in the type. Genital atrium opening on left margin of body at a distance of 0.55-0.8 mm from head end. Ovary tubular, long, folded back on itself just medial to left intestinal limb, 0.3-0.4 mm long lineally as a whole, arising about one-third of body length from posterior extremity. Germiduct giving rise to genitointestinal duct before joining vitelline reservoir. This duct opens into the left intestinal limb a little anterior to the distal end of the ovary. Uterus midventral, containing only one fusiform egg in the type. Eggs 0.17-0.18 mm long, with rigid bipolar filaments 0.15-0.21 mm long. Vitellaria largely co-extensive with intestine, commencing a little behind vaginal pore and terminating at base of opisthohaptor; vitelline reservoir

Discocotylidae

DISCUSSION

105 HABITAT HOLOTYPE DESCRIPTION

137

Y-shaped, in ovarian zone. Vagina funnel-shaped, strongly muscular, sending out a short narrow duct on each side of its anterior end. This duct appears to be connected with the anterior end of the longitudinal vitelline duct of its own side, although no distinct connecting duct is seen. Vaginal pore middorsal, postbifurcal, provided with a conspicuous bulb of fine lamellar muscle fibers, situated at a distance of 1.2-2.25 m m from head end. This genus differs markedly from Opisthogyne Unnithan, 1 9 6 2 in the distribution of the testes. In Opisthogyne the testes are limited to the pre-ovarian region, whereas in the present genus they are much more numerous and more extensive. The V-shaped ridges characteristic of Opisthogyne and Gemmacaputia Tripathi, 1959 are absent in the posterior part of the body in the present genus.

Pseudopisthogynopsis

lepidocybii Yamaguti,

1965

FIGURE 1 0 5

Gill of Lepidocybium flavobrunneum; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 2 . (Based on 50 whole mounts.) Body elongate, 5 - 1 3 mm long, 0 . 5 5 - 1 . 4 mm wide just in front of opisthohaptor, tapering anteriorly, symmetrical except for posterior end, to which four larger subsessile clamps are attached on the side of the genital pore and four smaller pedunculate clamps on the other side, without hook-bearing appendage between two posterior-most clamps. Skeleton of small clamp 1 0 0 - 1 7 0 ¡x wide, consisting of two pairs of symmetrical or slightly asymmetrical, unjointed, lateral sclerites, a median spring with bifid ends of which the shorter prong has a V-shaped apical piece, a pair of accessory sclerites, and a pair of short basal sclerites; skeleton of larger clamp 2 8 0 - 4 2 0 ¡j. wide at base, consisting of two pairs of distinctly asymmetrical, unjointed, lateral sclerites, a median spring with bifid ends, a pair of accessory sclerites, and a pair of basal sclerites. On the tip of the shorter, fenestrated prong of the median spring is set a V-shaped, more weakly sclerotized, apical piece. The capsule of the larger clamp is more muscular than that of the smaller clamp, and its proximal outer quadrant is so much developed as to push the lateral and basal sclerites of its own side toward the apex of the clamp, thus causing asymmetry of the clamp skeleton; the lateral sclerites of the proximal outer quadrant showing a gentle curve in contrast with opposite lateral sclerites. Head blunt-pointed, 0 . 2 - 0 . 4 2 mm wide at level of ventral mouth aperture, with a pair of well-developed apical organs. Oral suckers elliptical, 0 . 0 6 - 0 . 1 1 X 0 . 1 - 0 . 1 8 mm, with septum at middle. Pharynx not muscular, 4 0 - 9 0 X 3 0 - 7 0 ¡1-, esophagus distinctly diverticulate posteriorly, 0 . 2 - 0 . 7 mm long, surrounded by pigment cells, bifurcating at level of vagina. Numerous outer intestinal branches extend outward through the very dense layer of vitellaria up to the very lateral margin of the body. In

138

DISCUSSION

the postovarian area the intestinal limbs are close to each other and terminate near the extreme posterior end of the body. Testes rounded, 90-185 in number, occupying whole interintestinal field in posterior half of anterior third and entire middle third of body, between vas deferens coils and ovary, in two zigzag rows anteriorly and three or four zigzag rows posteriorly. Vas deferens surrounded by numerous prostate-like cells in postbifurcal interintestinal area. From a little anterior to the vaginal pore extends forwards in the median field a slightly winding muscular pars prostatica 0.22-0.6 mm long by 30-65 p. wide and surrounded by numerous prostate cells; it passes into the strongly muscular ejaculatory duct which is 0.1-0.25 m m l° n g by 30-60 ¡x wide and usually turns back on itself at its anterior end to be continued into the cirrus. Cirrus simple, unarmed, enclosed in cylindrical, muscular cirrus pouch. Latter 0.16-0.25 mm long, 40-60 ¡x wide, provided with longitudinal muscle fibers, extending obliquely toward left margin of body. Genital atrium 93 p. wide in the type, surrounded by accompanying cells, provided with circular muscles, opening ventrosubmarginally at a distance of 0.44-1.0 mm from head end. Ovary longitudinally elongated, shaped like number 8, situated in anterior half of caudal third of body, with both ends directed backwards, 0.9-2.3 X 0.12-0.3 mm; proximal part multilobulated in a rosette-shape, next ascending portion tubular, crossing descending distal portion dorsally; descending distal portion winding backward medial to right intestinal limb and then medial to ascending tubular portion. Genito-intestinal duct provided with circular muscle fibers, arising from germiduct just in front of junction of germiduct with stem of vitelline reservoir, opening into right intestinal limb at level of distal end of ovary. Uterus midventral, opening into genital atrium alongside cirrus pouch on its posteroventral side. Eggs elliptical, 0.22-0.25 mm long by 50-70 ¡x wide; bipolar filament rather rigid, 0.2-0.35 mm long. Vagina surrounded by lamellae of circular muscle fibers like a sphincter, opening midventrally at a distance of 0.95-2.2 mm from head end; paired accessory vaginal ducts arising sideways from base of vagina, first running transversely, then turning backward at the point provided with sphincter-like circular muscle fibers, may be distended with sperm together with yolk cells before uniting with transverse commissure of anastomosing anterior-most vitelline ducts; median vaginal duct proper traceable in median field for some distance back of vagina, but its posterior termination not determined. Vitellaria extending in lateral fields, commencing at level of vaginal pore, confluent in postovarian median field; vitelline reservoir Y-shaped; longer right arm crossing swollen distal portion of ovary on its ventral side; stem long, descending on left side of terminal descending portion of ovary. This genus differs from Pseudopisthogyne only in the absence of the hook-bearing caudal appendage. For additional details, see Pacific Science 19(1)78-80.

Discocotylidae

Subfamily

106 HABITAT HOLOTYPE DESCRIPTION

VALLISIINAE

139

Price, 1943

Vallisiopsis sphyraenae n. sp.

FIGURE 1 0 6

Gills of Sphyraena barracuda (type host) and S. helleri; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 169. (Based on two whole mounts from type host and nine more from other host.) Body bent in form of a letter N behind middle, 3 . 5 - 1 0 mm long lineally, 0.7-2.1 mm wide at level of flexure, narrowest isthmus about 0.3-0.6 mm wide; anterior portion 2.65-6.6 mm in length including rounded posterior flap which is 0.26-0.56 X 0.3-0.72 mm; posterior portion 1.9-4.5 m m l° n g from its broadly rounded anterior flap to tip of obliquely truncated posterior extremity. No transverse annulations as observed in Vallisiopsis contorta Subhapradha, 1951. Opisthohaptor oblique, 0.8-1.0 mm long, with ventral lobes separated one from another by deep slit-like notches, provided at posterior end with a small, rounded or truncate conical, caudal lobe bearing a pair of hooks 2 7 - 3 3 ^ between two hooks there are two pairs of very small hooklets. Number and position of clamps variable. In the type there are three clamps as shown in the figure; in the paratype, however, only one clamp is present at the tip of the second lobe, and in another paratype there are eight altogether. Clamp skeleton 50-95 ¡T. in diameter, with distinct accessory sclerites; median spring anchor-shaped at tip of longer ventral prong, with wing-like apical piece on shorter dorsal prong. Head rounded, mouth anterior to and between two oral suckers; suckers oval, distinctly septate, 25-60 X 18-60 /JL. Pharynx 3 5 - 8 1 X 2 5 - 7 0 /t; esophagus simple, 0 . 3 4 - 1 . 2 mm long; intestinal limbs with short side branches except at isthmus, terminating separately, but their posterior branches may be confluent. Testes rounded, 10-34 ' n number, in pre- and para-ovarian interintestinal field of posterior portion of body; posterior two or three to left of ovary. Vas deferens winding ia median field, provided with thick muscular walls at postbifurcal distal portion where it is surrounded by prostatic cells, though it does not appear like the pars prostatica; the muscular element of the wall becomes gradually reduced anteriorly. Cirrus funnel-shaped, with apical crown of very fine acicular spines, opening into circular genital sucker; the latter is about 0.12 mm in diameter in the type, mainly composed of strong radial muscles, and provided along the inner margin with a crown of 2 2 - 3 2 hooks (28 P. long), the tip of which is curved outward. Genital pore oval, opening anteroventral to genital crown of hooks at a distance of 0.2-0.64 m m fr°m head end. Ovary 0 . 3 5 - 1 . 2 mm long lineally, situated in interintestinal field close to posterior extremity, with its proximal portion branched and its straight distal portion turned back on itself on the right of median line. The germiduct arising from backwardly directed distal end of the ovary gives

140

DISCUSSION

Subfamily 107 HABITAT HOLOTYPE DESCRIPTION

off the genito-intestinal canal just before joining the vitelline reservoir. Shell gland sinistroventral to proximal portion of ovary; uterus ventral to vas deferens. Eggs fusiform, 2 0 0 - 2 1 5 l° n § by 5 0 - 6 5 p. wide; anterior filament 1 4 0 - 2 0 0 ¡t. long, posterior filament 200-300 ¡t. long. Vagina funnel-shaped, with wide opening on left body margin level with intestinal bifurcation; vaginal duct could not be traced. Vitellaria co-extensive with intestine except for very beginning of latter devoid of side branches and at isthmus. Vitelline reservoir Y-shaped, confined to ovarian zone; its arms may be nearly horizontal, each connected with long seminal receptacle extending longitudinally medial to intestinal limb in ovarian zone in fully mature specimens. This species differs from the only known member of the genus, Vallisiopsis contorta Subhapradha, 1951, in body size, in the testes being largely preovarian, etc. In the Indian species the genital pore is stated to be armed with a crown of hooks; this crown is seen along the inner margin of the genital sucker in the Hawaiian species. The measurements made on our specimens from Sphyraena helleri are distinctly smaller than those made on the specimens from the type host, but I prefer not to regard the differences as of specific importance. The connection of the paired seminal receptacles with the arms of the vitelline reservoir occurs in fully mature specimens alone. The same is probably true with the Indian species.

PSEUDODISCOCOTYLINAE

Yamaguti,

1965

Pseudodiscocotyla opakapaka Yamaguti, 1965

FIGURE 1 0 7

Gill of Pristipomoides microlepis (local name "opakapaka") and Aphareus rutilans; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 13. (Based on 20 whole mounts.) Body tapering anteriorly, 1 . 6 - 2 . 7 mm in length, with maximum width of 0.22-0.6 mm at posterior half of body. Opisthohaptor with a median pair of larval hooklets at posterior end, divided into symmetrical lobes, each bearing an oblique row of four subequal clamps; clamp skeleton 0 . 1 - 0 . 1 8 mm wide, consisting of a dorsal and a ventral pair of slender, unjointed, lateral arms, a median spring with bifid ends, and a pair of incurved basal rods. Head truncate, 0 . 1 5 - 0 . 2 mm wide. Paired oral suckers septate, 4 0 - 7 0 X 6 0 - 1 1 0 /A. Pharynx pyriform, 30-60 X 3 0 - 4 5 p; esophagus short, bifurcating just behind bulbus cirri; ceca with short inconspicuous diverticles, extending into opisthohaptor, terminating very close to each other near wide posterior sinus between two lobes of opisthohaptor. Testes 5 0 - 1 0 0 in number, occupying nearly whole postovarian intercecal field, divided into two lateral groups from behind ovary to level

Hexostomatidae

DISCUSSION

Family 108 HABITAT HOLOTYPE DESCRIPTION

141

of shell gland. A stout ellipsoidal bulbus cirri about 75 X 60 ¡X., provided subapically with a median group of 12 minute acicular spines and a pair of longer, very slender, lateral spicules, and apically with a certain number of slightly curved spines massed together; genital atrium with a crown of two alternating rows of minute spines, opening midventrally at a distance of 0 . 1 7 - 0 . 3 5 mm from head end. Ovary bent back on itself, with its distal end directed backward, 1 0 0 - 1 7 0 X 6 0 - 1 1 2 ¡X, situated on the right of median line just in front of middle of body. Genito-intestinal duct opening into right intestinal limb. Uterus strongly distended with eggs in some specimens. Eggs elliptical, 1 6 0 - 1 8 0 X 6 0 - 7 0 ¡JL, with a very long, fine, convoluted filament at each pole. On the ventrolateral surface of the body at a distance of 0 . 2 7 - 0 . 4 5 mm from the head end there is a pair of oval symmetrical vaginae lined with corrugated cuticle, but their vaginal ducts could not be made out. Vitellaria commencing behind vaginae and extending along whole length of intestine except for its anterior-most portion; vitelline reservoir Y-shaped, median, with its arms at level of ovary and its stem between two submedian groups of testes. It is very remarkable that each arm is distended with sperm at its anterior end in the form of an oval sac. This genus resembles Discocotyle Diesing, 1 8 5 0 in general anatomy, but differs from it in the intestinal limbs not uniting posteriorly, in the heavily armed bulbus cirri, and the armed genital atrium, etc. It obviously belongs to Discocotylidae Price, 1936 but cannot be assigned to any of the know subfamilies; hence a new subfamily was proposed for its reception in 1 9 6 5 . For further details, see Pacific Science 1 9 ( 1 ) ¡ 8 2 - 8 3 .

HEXOSTOMATIDAE Price, 1936 Hexostoma keokeo n. sp.

FIGURE

108

Gills of Auxis thazard (local name "keokeo"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 7 0 . (Based on five whole mounts.) Body 4 . 6 - 7 . 5 X 1 . 5 - 2 . 8 mm, tapered anteriorly to a sharp point, bulging out on each side immediately in front of opisthohaptor in form of a hemispherical lobe covered with cuticular papillae, each of which is produced into a fine point. Opisthohaptor 1.22.1 mm wide, covered up laterally by above mentioned semicircular papillate lobe, provided on ventral side of broadly convex posterior margin with four pairs of sucker-like sessile clamps, with two pairs of caudal anchors between innermost clamps; a set of three heavily sclerotized fixation apparatuses enclosed in oval, bivalved muscle pad ( 3 7 - 5 1 X 2 3 - 4 2 fi) as in Hexostoma; anterior and posterior pieces of each clamp rather simple in structure, though different in shape for each clamp,

142

9~i8 fi and 1 1 - 2 1 ¡1 in length respectively; the central piece is more complex and perforated as shown in the figure, 16-30 ¡x long transversely. Outer caudal anchor up to 120 j* long, with a very prominent guard a little shorter than blade; inner one 18-37 f- long, with terminal claw. Oral suckers muscular, 30-58 X 21-37 /*» c ' o s e together; pharynx elliptical, non-muscular, 39-51 X 28-39 esophagus 0.5-0.7 mm long, with several, narrow, anastomosing, lateral branches on each side posteriorly, bifurcating immediately in front of genital pore. Ceca also with similar anastomosing lateral branches anteriorly, but more numerous reticulate branches posteriorly; this intestinal network extends well into the lateral prehaptoral lobes to their margins and up to the posterior margin of the haptor through the space between the clamps.

DISCUSSION

Testes transversely elongated, 17-28 in number, massed together in prehaptoral median field, partly overlapping posterior vitellaria. Vas deferens distended with sperm and strongly twisted in median field anterior to ovary beside uterus, but straightened out more anteriorly and leading into narrow ejaculatory duct, at the distal end of which is a weakly muscular, ovoid, cirrus bulb 35-77 long by 28-46 /*. wide. This bulb opens anteriorly into the spherical genital atrium, which in turn opens midventrally just in front of the cirrus bulb by a circular aperture. Ovary tubular, winding all the way through, measuring 0.7-1.0 mm long as a whole, originating in the type to right of median line at junction of middle with posterior third of body, crossing right arm of vitelline reservoir and ascending on the left of median line to equatorial level, where it turns to the right across the vas deferens, and descending on the right of median line leads into the germiduct, which passes obliquely backward parallel to the right arm of the vitelline reservoir and unites with the stem of the latter after giving rise to the genitointestinal duct. A small receptaculum seminis connected with the germiduct is seen in the largest specimen 7.5 mm long in form of an elongate sac filled with sperm and measuring 0.3 mm long by 0.14 mm wide. Uterus midventral; eggs fusiform, 160-200 long by 70-90 p wide; polar filament rigid, up to 180 p long. Vagina represented by symmetrical elongate pads which are 70-82 ¡x long, covered densely with conical teeth and connected dorsally by transverse muscle fibers opening middorsally at its apex; vaginal duct inverted Y-shaped. This species is characterized by the paired, papillated, prehaptoral, lateral lobes and the testes being massed together in this prehaptoral zone. It is to be noted that in a juvenile form this prehaptoral lobe is completely absent, although the haptoral clamps are well developed in symmetrical, nearly vertical rows and the anchors are on a prominent hemispherical terminal lobe. In Hexostoma auxisi Palombi, 1943 from Mediterranean Auxis thazard there are no papillated prehaptoral lobes, so it can be easily excluded from comparison. The specific name is the local name for the host.

Hexostomatidae

109 HABITAT HOLOTYPE DESCRIPTION

Hexostoma sibi n. sp.

143

FIGURE 1 0 9

Gills of Neothunnus macropterus (type host, local name "sibi"), Parathunnus sibi and Thunnus alalonga; Hawaii. U.S. Nat Mus. Helm. Coll., S.Y. No. 1 7 1 . (Based on 30 mature specimens.) Body 1 2 - 3 0 mm long, 4 . 0 - 6 . 0 mm wide in midregion, divided into four regions of different width; the first region comprising prohaptoral suckers, pharynx, and anterior part of esophagus is 0 . 5 8 - 0 . 7 mm long and shaped like a blunt-pointed terebratorium; the second region nearly uniform in width, between the first region and the genital pore; the third region occupying the greater middle portion of the body; the fourth region constricted from the third and enlarged transversely, with its long axis at varying, often acute angles to the body axis, 4 . 0 - 8 . 5 mm wide, bearing four pairs of ventral haptoral suckers and two pairs of anchors at median terminal notch. The four suckers on each side are elliptical and subequal, the innermost being definitely reduced in development, 0 . 2 - 0 . 3 8 x 0 . 1 7 - 0 . 3 1 mm, whereas the others are 0 . 4 6 - 0 . 8 X 0 . 3 8 - 0 . 6 mm. The clamp sclerites of each sucker vary in size and structure, the largest middle sclerite of larger suckers being 0 . 2 - 0 . 3 7 m m l°n§> shaped like a steam iron, consisting of a flat base and a handle formed by fusion of two lateral arms arising from the base; in the innermost sucker 0.090.2 mm long, the lateral arms are separate; the anterior and posterior sclerite 0 . 1 2 - 0 . 2 4 mm and 0 . 1 3 - 0 . 2 6 mm in respective length in the larger suckers, 0 . 0 6 - 0 . 1 1 mm and 0 . 0 5 - 0 . 1 3 mm long respectively in the innermost sucker. Outer terminal anchor 0 . 0 9 - 0 . 1 7 mm long, with a prominent guard and a well curved blade; inner anchor nearly similar in shape, 2 5 - 4 2 ¡i long. Head rounded off, smooth, 0 . 1 - 0 . 2 mm wide, with mouth opening ventroterminally. Buccal cavity narrow, provided just in front of pharynx with a pair of small, weakly muscular, prohaptoral suckers 2 5 - 5 1 X 2 0 - 5 4 l £ A R M 0 . 3 - 0 . 4 7 X 0 . 1 4 - 0 . 1 8 mm; of the two pairs of anchors the outer ones are wide apart (0.32 mm in the type), each with stout bifurcate base, 3 0 - 3 8 ¿x from height of curve of blade to tip of dorsal root, the inner ones 60 y. apart one from the other in the type, 15-20 ¡x from tip of blade to base. The truncate posterior extremity of the body proper encloses a wide cavity which is covered ventrally by the body folds approaching each other, leaving a longitudinal slit reaching the row of the clamps. The four clamps are arranged in a transverse row slightly oblique to the longitudinal axis of the body on the right side of the peduncle of the H-shaped appendage. The clamp skeleton 4 0 - 8 0 X 8 0 100 ft., consists of a U-shaped unpaired median piece, a pair of slightly curved inner rods, a fused ventral arc, and a pair of dorsal arcs jointed in the median line by their recurved points; the dorsal prong of the median piece is bifurcated at the apex, but the ventral prong is shorter and bluntpointed. Mouth aperture about 70 ¡x wide, ventroterminal; paired oral suckers unarmed, elliptical, aseptate, 300-450 X 500-650 ¡x; pharynx 7 7 5 925 X 6 7 5 - 8 0 0 ¡x. Esophagus 0 . 7 8 - 1 . 2 mm long, showing elliptical dilatation at beginning, with 1-2 diverticles on pore side in front of genital pore, 3-5 diverticles on opposite side in front of vaginal pore, pushed to the vaginal side by terminal genitalia, bifurcating usually at level of base of vaginal bulb. Intestinal limbs with numerous, simple or branched diverticles, mostly on outer side, terminating separately near posterior extremity. Testes mostly rounded or somewhat irregular in outline,

101-153

Protomicrocotylidae

149

number, arranged in one layer and occupying nearly whole intercecal field of middle third of body. Vas deferens convoluted at anterior limit of testicular region, tapering anteriorly before leading into pars prostatica; latter long, mainly postbifurcal, median, surrounded by prostatic cells. Ductus ejaculatorius forming a bulbous swelling at base of cirrus pouch. Cirrus pouch 90-100 X 100-120 with a very thick wall of circular and longitudinal muscle fibers, armed inside with a circle of 17, slightly curved spines varying in length from 110 ¡¡, to 180 p., each spine with a more or less curved, acute point and a very prominent guard distal to its middle; its distal portion projecting into genital atrium, with the point in- or outside of the atrium. Genital pore opening ventrally close to right or left body margin a short distance anterior to intestinal bifurcation. Ovary approximately M-shaped, 0.7-1.08 X 0.24-0.35 mm, situated in median field at junction of middle with posterior third of body. It is not certain whether the proximal end of the ovary is convoluted or compact, but there is no tubular duct connecting this portion with the rest of the organ, though somewhat narrowed at this connection; the other tubular portions of the ovary are pressed against each other, and the distal swollen portion is directed backward along the stem of the Y- or T-shaped vitelline reservoir. The germiduct gives rise to the genito-intestinal canal just before joining the stem of the vitelline reservoir and after uniting with it runs backward for a short distance and turns forward to lead into the ootype. Uterus ventromedian for most part, passing alongside vas deferens coils and pars prostatica, finally opening outside at outer margin of genital pore. Eggs elliptical, 200-220 X 60-90 ¡i, produced at each end into a rigid filament 0.18-0.28 mm long. Vitelline follicles small, filling up spaces among cecal branches. At the posterior extremity the vitellaria extend further backward on the pore side than on the vaginal side, and enclose one clamp at the extreme end of the row completely or almost completely. DISCUSSION

This species differs from the most closely related Neomicrocotyle indica Ramalingam, i960 in the following points: (1) in N. indica the body is 3.59-4.67 X 0.8-1.5 m m > whereas in N. carangis it is larger, 5.9-7.0 X 1.01.6 mm; (2) in N. indica the long esophagus is shown to be devoid of diverticles, but I can see no reason why Ramalingam showed neither the esophageal diverticles nor the cecal diverticles if they were actually present as in the Hawaiian species; (3) the cirrus is provided in the Indian species with a crown of 24 hooks, but in the present species there is no Crown of hooks at the distal end of the circle of longer cirrus spines; and (4) it is stated that the uterus of N. indica opens midventrally posterior to the male pore, but from my observation of N. carangis it seems doubtful that the uterine pore is midventral. Abortipedia Unnithan, 1962 is undoubtedly identical with Neomicrocotyle Ramalingam, i960, although the intestinal limbs were shown, obviously by mistake or negligence, by Ramalingam to be simple in Neomicrocotyle. From the difference in the posterior extent of the testes and in the

1

5°

structure of the haptoral anchors it seems certain that Neomicrocotyle indica (Unnithan, 1962) is specifically different from N.indica Ramalingam, i960, so I prefer to rename Unnithan's species Neomicrocotyle unnithani. In Unnithan's description of this species there are several points which should require re-examination and on which I venture to comment as follows: (1) the cells surrounding the genital pore (p. 343) are not to be interpreted as prostatic cells; (2) the genito-intestinal canal is stated by Unnithan to leave the ootype (p. 344); he obviously mistook the stem of the vitelline reservoir for the genito-intestinal canal (cf. Fig. 42); (3) Unnithan's statement that the vaginal duct opens into the ootype close to the oviduct in N. unnithani is open to doubt; and (4) the thickened capsules of the clamps bear "glands" (p. 346) according to Unnithan, but this cannot be accepted. In spite of these errors or misinterpretations by Unnithan for N. unnithani, there is no doubt that this species differs from N. carangis. Unnithan definitely states (p. 346) that in his Indian species the esophagus has no diverticula. Protomicrocotyle pacifica Meserve, 1938, transferred by Unnithan to his Abortipedia, should be assigned to Neomicrocotyle Ramalingam.

Family

114 HABITAT HOLOTYPE DESCRIPTION

PTERINOTREMATIDAE Bychowsky et Nagibina, 1959 Pseudopterinotrema albulae Yamaguti, 1966

FIGURE

114

Gill of Albula vulpes; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 49. (Based on 26 whole mounts.) Body slender, cylindrical, 1.75-2.4 mm in length exclusive of haptoral clamps, up to 4.5 mm in length including clamps, 0.12-0.26 mm wide in ovariotesticular region. Opisthohaptor fanshaped, asymmetrical, on posterior extension of body proper, with nine pedunculate clamps. As numbered from the right end of the opisthohaptor of the type, the first to the ninth clamp present different features as follows: 1) 1st clamp divided into a caudal appendage bearing a pair of large subapical anchors and two more, very small, apical hooklets, and a shorter clamp than others. This clamp consists of two opposing valves fringed on each side with about a dozen curved spines and is supported by comparatively short stout sclerites. 2) 2nd clamp arising from common trunk with 1st, consisting of a slender stalk provided on each side with membranous fringe supported by a row of about a dozen acicular spines and a single axial sclerite; apical clamp valve single, fringed with over a dozen curved spines. 3) 3rd clamp with two-valved sucker at base, its stalk supported by two unequal axial sclerites, one of which articulates with the sclerite of

Pterinotrematidae

151

the 2nd clamp at the base, while the other slender one articulates with the stronger axial sclerite of the 4th clamp; axial clamp valves pressed against each other. 4) 4th clamp similar in structure to the 3rd, with double apical clamp valve, bearing at base a two-valved sucker on the right and a larval lappet on the left. This lappet is a plump rod-shaped lobe and bears two pairs of very small larval anchors. 5) 5th clamp with sucker at base, its apical valve consisting of two similar valves. 6) 6th clamp with double apical valve similar in structure to that of 3rd. 7) 7th clamp with symmetrical terminal clamp valves. 8) 8th clamp with two separate apical valves and a common stalk supported by two parallel axial sclerites, of which the right one articulates with the left axial sclerite of the 7th clamp and the left one articulates with the extreme left 9th sclerite. 9) 9th clamp fringed on each side with a row of spines like other clamp stalks, but bears only one apical clamp valve, although it has a twovalved sucker on the left side of its base. The above-mentioned two-valved suckers 23-40 ¡x wide and seven in all, are arranged in a transverse row at the base of the clamps. Each sucker has a sclerotized frame consisting of four sclerites and appears 00 -shaped in profile. _ Prohaptor circular, 0.2-0.47 mm in diameter, membranous, with somewhat crenulated margin and a simple middorsal cone 40-70 ¡i long and 40-70 /x wide at base. Oral sucker 0.11-0.21 mm in diameter, opening at bottom of prohaptor; prepharynx present; pharynx always lateral to oral sucker, 40-60 X 20-30 /¿; esophagus very narrow, 0.3-0.65 mm long; ceca with short branches, terminating separately at base of opisthohaptor. Testes rounded, up to 25 in number (mostly 16), arranged in a zigzag longitudinal row, occupying greater part of postovarian interintestinal field. Vas deferens may be strongly swollen in preovarian interintestinal field. Cirrus plug-shaped, muscular, covered inside with spinules, 50-90 X 27-50 p, with two unequal sclerotized filaments at base; anterior filament 50-120 fx long, usually widened distally, posterior hook-shaped, 35-60 p. long, both often appressed against cirrus. Genital pore ventromedian, 0.060.22 mm posterior to pharynx. Ovary turned back on itself five times, forming N-shaped loop posteriorly and double loop anteriorly, situated in anterior part of middle third of body. The germiduct running forward gives off the genito-intestinal duct near its origin and soon unites with the descending vitelline stem. Uterus largely ventromedian; eggs elliptical, 110-130 X 50-75 ¡x, with long, very fine filament at antiopercular pole. Vitellaria co-extensive with intestinal limbs; vitelline reservoir Y-shaped, with long, sometimes short stem, and rather short arms, coinciding with ovary. Vagina well cuticularized, with wide middorsal opening 0.1-0.35 m m posterior to genital

152

DISCUSSION

Superfamily Family Subfamily

115 HABITAT DESCRIPTION

pore, usually anterior to anterior end of vitellaria, but sometimes much posterior to this level. Vaginal duct inverted Y-shaped, each branch opening into arm of vitelline reservoir of its own side. This genus bears a superficial resemblance to Pterinotrema Caballero, Bravo-Hollis et Grocott, 1954, but it differs fundamentally in the structure of the clamps and the terminal genitalia and in possessing a typical oral sucker and a pharynx. I preferred to separate it as representing a new genus, for which the name Pseudopterinotrema was suggested in 1966.

MICROCOTYLOIDEA Unnithan, 1957 AXINIDAE Unnithan, 1957 AXININAE

Monticelli, 1903

Axine belones Abildgaard, 1794

FIGURE 1 1 5

Gills of Parexocoetus brachypterus; Hawaii. (Based on five whole mounts.) Body lanceolate, 3.5-4.0 mm long, 0.250.42 mm wide at level of ovary, wider posteriorly. Opisthohaptor 0.130.18 mm long, with 53-69 clamps; clamp skeleton 25-60 ¡x in diameter, consisting of two pairs of slender lateral arms, a pair of slender, medial, basal pieces, and a median spring, of which the longer prong is bifid at the tip, whereas the short prong has a terminally bifid apical piece; prehaptoral larval hooklets of two pairs, about 35 ^ and 46 /A long respectively. Head rounded, 80-100 ¡n. wide, with an apical organ on each lateral margin of mouth; oral sucker aseptate, 44-70 X 25-46 ft, file-like on inner surface. Pharynx subglobular, 23-26 X 16-23 /¿; esophagus 0.35-0.45 mm long, bifurcating posterior to genital pore; ceca with short side branches, terminating separately at different levels at base of cotylophore. Testes rounded, 15-20 in number, arranged in a zigzag longitudinal row, extending from behind ovary to near posterior end of interintestinal field. Vas deferens winding forward along uterus, surrounded by numerous prostatic cells anterior to ovary. Cirrus conical, smooth, projecting into genital atrium. Genital atrium with four spiny pads; anterior pad with 10-14 apically incurved spines; symmetrical lateral pads each with semicircular row of 16-22 smaller spines; posterior pad with a semicircular row of 18-21 backwardly pointing spines. Genital pore 0.34-0.6 mm from head end. Ovary subcylindrical, turned back on itself posteriorly at anterior part of middle third of body, with both ends directed forward, measuring 0.250.4 X 0.08-0.17 m m a s a whole. Shell gland cells massed together on left side of vas deferens at level of anterior end of ovary. Eggs not observed. Vagina 18-21 X 7-9 ¡¡., consisting of funnel-shaped, cuticular, distal portion and spherical, non-muscular, bulbous portion, opening ventrally close

Axinidae

DISCUSSION

116 HABITAT HOLOTYPE DESCRIPTION

153

to right margin of body, 0 . 5 5 - 0 . 7 5 mm from head end. Vaginal duct also consists of two portions of different structure; distal portion composed of folded cuticular lining and inner circular and outer longitudinal muscle fibers, proximal portion elongate funnel-shaped, with thick wall of longitudinal muscle fibers and lined with minute scales, opening into vitelline reservoir at junction of its two arms. Seminal receptacle oval, 0 . 1 - 0 . 1 3 X 0 . 0 7 - 0 . 0 8 mm, situated between right cecum and vas deferens a little anterior to ovary. Vitellaria co-extensive with intestine, commencing at level of funnel-shaped proximal portion of vaginal duct a little posterior to vaginal pore. The specimens at my disposal, though small, agree well in essential particulars with the figure given by Bychowsky (1957) for this species, and also with the descriptions by Sproston ( 1 9 4 6 ) and Brinkmann (1952) in the number of clamps.

Axine depauperati n. sp.

FIGURE

116

Gills of Hemiramphus depauperatus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 7 4 . (Based on eight whole mounts.) Body slender, 2 . 2 - 3 . 4 M M l°n§> 0.160 . 2 5 mm wide in midregion. Opisthohaptor 0 . 5 - 0 . 8 mm long, with a row of 22-31 clamps, of which one may or may not be out of the row at the posterior end of the body axis. At this extra clamp may be found two pairs of larval hooklets of different shapes, 3 0 - 3 9 P clamp skeleton of Microcotyle type; both prongs of median spring bifid at tip, without accessory apical piece. Head 6 5 - 8 0 p. wide, rounded, with a pair of apical organs. Oral sucker oval, 3 0 - 4 4 ¡x. long, with denticulate margins. Pharynx oval, very poorly muscular, 2 8 - 4 6 X 2 3 - 3 5 esophagus 0 . 2 - 0 . 3 8 mm long, bifurcating just anterior to genital pore; ceca diverticulate on each side, terminating separately at posterior end of body proper. Testes round to elliptical, 29-41 in number, arranged in a longitudinal zigzag row and occupying almost entire postovarian interintestinal field, though not reaching level of intestinal ends. Vas deferens narrow, surrounded by prostate cells anterior to ovary. Cirrus proper conical, unspined, 1 8 - 2 3 P ' n diameter. Genital atrium with a semicircle of 4 0 - 5 0 minute spines 7 - 1 4 ¡1 long, opening 0 . 3 3 - 0 . 5 5 mm from head end; this semicircle is interrupted midventrally, and divided into three (a median anterior and two lateral) portions; median group consisting of 2 6 - 2 8 spines, and lateral group of 18-24 spines. There is another posterior spiny pad 17 ¡a. in diameter and bearing a group of ten straight, apically curved spines 11-13 Z4 longOvary narrow, turned back on itself on right side of median line at anterior part of middle third of body, with both ends directed forward. The germiduct arising from the anterior end of the ovary runs forward to form elongate seminal receptacle 46 /i by 33 ¡i in the type; genito-intestinal

154

DISCUSSION

117 HABITAT HOLOTYPE DESCRIPTION

canal short, opening into right intestinal limb at level of arms of vitelline reservoir. It is unusual that the germiduct empties directly into the stem of the vitelline reservoir immediately behind the junction of the two arms. Shell gland cells are massed around the beginning of the uterus. Uterus midventral, containing no eggs. Vitellaria co-extensive with intestine, commencing on each side shortly posterior to level of vaginal pore. Vitelline reservoir T-shaped, 0 . 2 6 - 0 . 3 8 mm long, with almost transverse arms, largely preovarian, median or slightly to left; junction of arms may be distended with yolk cells in form of a bulb. Vagina fusiform, 39 X 11 p in the type, distal portion well cuticularized inside, opening on right margin of body, proximal portion well provided with longitudinal muscle fibers and covered inside with comparatively few blunt denticles. A truncatepointed, 2-segmented, hollow, elongate conical peg about 45 ¡i long is seen projecting into the distal lumen of the vagina. Vaginal duct short, opening into bulbous swelling of vitelline reservoir mentioned above. This species differs from the most closely related Axine hemiramphae Unnithan, 1957 from Hemiramphus xanthopterus of India in possessing definitely fewer clamps and testes. In the Indian species the clamps are 4 8 - 5 1 in number and the testes are 5 0 - 6 5 in number and arranged in two or three longitudinal rows. Also, in that species the vaginal duct forms a distinct seminal receptacle anterior to the ovary, while in the Hawaiian species the seminal receptacle is formed by dilatation of the germiduct, not by the vaginal duct. It is worth noting that the germiduct opens directly into the vitelline reservoir and that the genito-intestinal duct connects this germiduct-vitellarian junction with the right intestinal limb.

Axine spilonotopteri n. sp.

FIGURE 1 1 7

Gills of Cypselurus spilonotopterus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 7 5 . (Based on 1 0 whole mounts.) Body 1 0 - 1 3 mm long, markedly tapered anteriorly but rather uniformly wide (1.8-3.3 m m ) f° r greater posterior part, obliquely truncated at posterior extremity. Cotylophore 2 . 8 - 6 . 3 m m long, bearing a row of 96-120 clamps, one of which may lie out of the row near the middle of the cotylophore. Larval hooklets present at posterior end of body axis. Clamp skeleton 6 0 - 1 0 0 p wide, of Microcotyle type; slender lateral arms jointed; apex of shorter prong of median spring truncate, that of longer prong anchor-shaped. Head end produced in the type into a pair of blunt hom-like processes, each of which is studded with compact mass of head gland ducts coming from head gland cells extending along each side of body in posterior esophageal region. Oral sucker oval, aseptate, 3 7 - 5 8 X 3 0 - 4 6 /»; pharynx pyriform, 3 5 - 5 8 X 2 8 - 4 6 esophagus simple, 0 . 9 - 2 . 0 mm long, accompanied posteriorly by pigment cells like intestinal limbs, bifurcating shortly behind genital atrium. In-

Axinidae

155

testinal limb with short inner diverticles, in addition to longer outer ones, but none at anterior portion not surrounded by vitellaria; both limbs terminating separately at posterior extremity of body proper. Testes rounded, 250-420 in number, arranged in one layer, occupying whole postovarian interintestinal field. Vas deferens distended with sperm, winding in median field between proximal end of ovary and transverse vitelline duct, but straightened out further anteriorly into narrower ejacuw latory duct; no pars prostatica differentiated. Cirrus 46-93 X 28-35 ^h bulbous base 42-81 ¡t. in diameter, projecting into genital atrium. Genital atrium with thick wall of radial muscle fibers which are sharply delimited from the surrounding by a membrane, armed inside with a semicircle of 18-22, apically recurved hooks 16-23 ¡x long. A circular muscle pad which is 46-105 /x in diameter, and on which over 50 slender rods 16-35 fare set, lies associated with the genital atrium, in the median line or a little to the right immediately behind the atrium as in Axine sasikala (Unnithan, 1957); sometimes this pad may be pushed forward into the genital atrium. Genital pore midventral, immediately in front of genital atrium. Ovary approximately U-shaped, with the two forwardly directed limbs pressed against each other, situated at junction of anterior with middle third of body; proximal limb 0.4-1.5 mm long, with its enlarged anterior end to left of median line and divided into several elongate lobes; distal limb 0.5-2.0 mm long, tapering anteriorly into straight germiduct which joins the seminal receptacle at the point where the genito-intestinal duct is given off; from this point the germiduct runs transversely to cross the vas deferens ventrally and finally unites with the common vitelline duct to form the recurrent uterine duct. This uterine duct widens in form of a spindle on the left of the descending germiduct. Only one normal uterine egg was seen in one paratype; it is oval, 0.17 X 0.1 mm, with a rigid filament at each pole; posterior filament about 0.3 mm long and anterior one about one-third as long. Genito-intestinal duct emptying into right intestinal limb immediately in front of origin of right arm of vitelline reservoir. Seminal receptacle retort-shaped, situated between vas deferens and right intestinal limb shortly anterior to distal end of ovary. Vagina opening widely dorsal to right intestinal limb at a distance of 1.1-3.05 mm from head end, with an outwardly directed, broad-based peg up to 46 long at its opening, surrounded by well developed circular muscles at the point where the vagina is constricted off from the fusiform proximal portion 0.25-0.5 mm long by 0.06-0.15 mm wide. This fusiform portion lies oblique-longitudinally ventral to ejaculatory duct and is continued backward into a straight vaginal duct which is usually distended with yolk cells and opens into the left arm of the vitelline reservoir close to the junction of the two arms. Vitellaria co-extensive with intestinal limbs and their branches from behind level of vaginal pore to posterior end of body proper; right and left vitelline arms joining together some distance (0.45 mm in

156

DISCUSSION

KEY TO SPECIES OF

Axine FROM HAWAIIAN FISHES

118 HABITAT HOLOTYPE DESCRIPTION

the type) posterior to vaginal pore to form a triangular reservoir, from which the common vitelline duct 0 . 3 - 0 . 4 mm long runs backward to join the germiduct as mentioned above. This species resembles Axine sasikala (Unnithan, 1 9 5 7 ) from Cypselurus oligolepis of India in the structure of the terminal genitalia, but differs from it in the number of the atrial spines, in the anatomy of the female genital complex (cf. Systema Helminthum Vol. 4, Fig. 852 b & c), and in the number of testes and clamps, and differs from other members of the genus from Cypselurus [Axine cypseluri (Meserve, 1 9 3 8 ) , A. japonica Price, 1945, A. parawa Unnithan, 1957, and A. yamagutii (Meserve, 1938)] in its larger body size and in the larger number of clamps and testes. The specific name refers to the specific name of the host.

1

Genital atrium with two spiny pads; clamps

testes A. spilonotopteri Genital atrium with four spiny pads: 2 Median spiny genital pad with larger spines anterior; clamps 5 3 - 6 9 ; testes 1 5 - 2 0 : A. belones Median spiny genital pad with larger spines posterior; clamps 22—31; testes 29—41: A. depauperati 96-120;

250-420:

Axinoides buïbosus n. sp.

FIGURE 1 1 8

Gills of Belone platyura; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 176. (Based on seven whole mounts.) Body tapered anteriorly, but somewhat bulging out laterally at level of genital pore, obliquely truncated at posterior end, along which extends the opisthohaptor 0 . 9 - 2 . 0 mm long and bearing one row of 4 4 - 5 7 clamps. Body length from head end to posterior end of opisthohaptor 1 . 6 - 4 . 0 mm, maximum width 0 . 2 5 - 0 . 5 mm at level of anterior end of opisthohaptor. Clamps at posterior end of body axis somewhat out of the row of other clamps, with two rudimentary larval hooklets in front on either side. Lateral sclerites of dorsal and ventral clamp valves jointed about middle; long prong of median spring anchorshaped at tip. No caudal appendage. Head blunt-pointed, 6 0 - 1 1 0 ¡i wide; paired oral suckers muscular, aseptate, 2 0 - 6 0 X 2 8 - 5 0 ¡x. Mouth ventroterminal. Pharynx rounded, 2 3 - 3 7 x esophagus bifurcating immediately behind vaginal pore; intestinal limbs with numerous outer branches, terminating separately at posterior end of body proper. Testes rounded, 12-17 number, arranged in one zigzag row, occupying entire postovarian interintestinal field. Vas deferens winding in preovarian median field; ejaculatory bulb fusiform to oval, may be distended with sperm, provided outside with a thin coat of fine circular and longitudinal muscle fibers which appear to extend over the cirrus. Cirrus subcylindrical, armed inside with numerous pointed spines. In the type

Axinidae

DISCUSSION

119 HABITAT HOLOTYPE DESCRIPTION

157

the shaggy cirrus is seen projecting out of the genital pore, the margin of which is provided with a ring of outer circular and inner longitudinal muscle fibers. Genital pore 30 ¡x wide in inside diameter in the type, situated at a distance of 0 . 1 8 - 0 . 4 mm from head end. Pars prostatica differentiated immediately behind vagina, surrounded by compact mass of prostatic cells which extend around the winding vas deferens too. Ovary 0.14-0.37X0.09-0.15 mm, nearly equatorial, arising from immediately in front of anterior-most testes and bent forward, giving rise to germiduct at its anteromedial end; germiduct forming a small receptacle (oval, 39 X 28 {i in the type) after giving off genito-intestinal canal; latter canal emptying into right intestinal limb at preovarian level. Eggs in utero 128 X 81 /x; posterior filament rigid, 93 X 10 ¡x. Vagina funnelshaped, finely spinose inside, opening middorsally a little anterior to intestinal bifurcation, 0.28-0.96 mm from head end. Immediately in front of the vaginal pore is a small blunt-pointed peg as in A. tylosuri Yamaguti, 1938. Vaginal duct provided with a small sphincter at anterior end, running straight backward in median field dorsal to uterus. Vitellaria commencing on each side a little behind vaginal pore, surrounding intestinal branches throughout their length; vitelline reservoir Y-shaped, pre-ovarian, receiving vaginal duct anteriorly. This species differs from all of the known members of Axinoides in the number of clamps, except for A. gracilis (Linton, 1940) from Tylosurus marinus (= Strongylura marina). This Atlantic species, however, is 2.0-5.2 mm long and nearly uniform in width throughout the body proper and bears 50-60 clamps and 1 4 - 2 0 testes; the ovary is stated to lie at about the anterior third of the body. It is to be noted that the swollen region of the genital pore bulges out laterally without exception in the present new species. The specific name refers to this character.

Axinoides diploporus n. sp.

FIGURE 119

Gills of Ablennes hians (local name "aha'aha"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 7 7 . (Based on 10 whole mounts.) Eight specimens were fixed in completely relaxed condition, so that the measurements taken from them are much greater than those from the other two which were fixed in the fresh state. Body lanceolate, very slender in relaxed specimens, 2 . 3 3 - 1 0 . 5 mm long, widest ( 0 . 1 7 - 0 . 4 5 mm) at base, along which a row of 4 3 - 5 5 clamps is attached. Clamp skeleton of Microcotyle type, consisting of very slender sclerites; one lateral arm apparently unjointed, but the other jointed at middle. On the opisthohaptor there are on one side two pairs of anchors close together toward the middle; the larger anchor is hook-shaped, 18-21 jx long from pointed anterior end to height of curve of blade, with ' o n & smaller anchor hook-shaped, only a simple slender rod 11-14 8-9 fx long, with muscle fibers attached to its base. Oral sucker septate,

i58

DISCUSSION

120 HABITAT DESCRIPTION

pectinate along anterior margin, 2 5 - 5 0 X 3 9 - 7 5 p.. Pharynx pyriform or elliptical, 3 0 - 5 0 X 20-60 (i; esophagus 0.4-1.1 mm long; intestinal limb with short side branches, terminating separately at base of opisthohaptor. Testes rounded, 30-62 in number, extending in a single zigzag row or two longitudinal rows in interintestinal field from equatorial level to near cecal ends. Vas deferens winding in median field; ejaculatory duct muscular, forming a small fusiform swelling 2 7 - 3 0 ¡t, long by 1 6 - 2 3 ¡x wide before passing into bulbous pars prostatica; cirrus elongate, muscular, enclosed together with pars prostatica in a sheath-like pouch, 7 0 - 1 6 0 X 2 0 - 3 5 >*•' unspined. Male genital pore immediately lateral or posterolateral to uterine pore. No common genital pore. Ovary U-shaped, with unequal arms, 0 . 2 4 - 0 . 5 5 mm lineally, 0 . 0 7 - 0 . 1 5 mm wide, immediately pretesticular; germiduct arising from right longer arm; genito-intestinal canal running forward and opening into right intestinal limb. Uterus with wide opening well provided with circular and radial muscle fibers immediately lateral or anterolateral to male pore. A single collapsed egg about 116 X 39 p, with rigid, relatively short filament at each pole. Vitellaria co-extensive with intestine except for its posterior end. Vitelline reservoir Y-shaped; stem short, may be up to 0.5 mm when fully extended; arms comparatively short. Vagina cylindrical, 6 5 - 1 2 0 X 1 3 - 1 6 p, lined with minute incurved spines, provided just in front of its postbifurcal middorsal opening with a broad-based, curved, hollow peg which is 16-25 /x long, truncated at its tip, surrounded by circular muscle fibers at its base; vaginal duct with a sphincter at distal end, its backward course could not be traced, though apparently opening into vitelline reservoir. This species is characterized by two separate genital pores, to which the specific name refers.

Axinoides kola Unnithan, 1 9 5 7

FIGURE 1 2 0

Gills of Ablennes hians (local name "aha'aha"); Hawaii. (Based on five whole mounts.) Body tapered anteriorly, 3 . 8 6 - 4 . 3 5 X 0.7-0.9 mm. Unilateral clamps 6 9 - 7 5 in number, with muscular capsule; lateral sclerites of dorsal valve jointed near base as stated by Unnithan ( 1 9 5 7 ) ; median spring anchor-shaped at tip; of the prehaptoral hooks only one, 2 0 - 2 2 fi long, with recurved ends, was seen in two out of five specimens at about posterior end of body axis. Prohaptoral suckers muscular, 3 2 - 5 0 X 4 0 - 6 8 /x; p h a r y n x 3 7 - 4 8 X 3 5 - 3 7 /x; e s o p h a g u s 0.8-0.9

m m

l°ng>

with rudimentary diverticles laterally; intestinal limbs with inner and outer branches, united posteriorly at posterior end of body proper. Testes small, rounded, very numerous (exact number not determined), occupying whole postovarian interintestinal area. Vas deferens closely winding from ovarian field up to vaginal area, then ascending nearly straight and leading into ejaculatory duct dorsal to intestinal bifurcation;

Axinidae

DISCUSSION

121 HABITAT HOLOTYPE DESCRIPTION

159

ejaculatory duct differentiated into two portions of different structure; narrower posterior part cylindrical, 27-45 x 7-5 /*•» provided with very fine circular muscle fibers; anterior portion bulbous, representing ejaculatory bulb, with thick walls of circular and longitudinal muscles; cirrus narrow except at its anterior end, armed with a crown of extremely small spines, provided with fine circular and longitudinal muscles and surrounded by accompanying cells which were interpreted by Unnithan as prostatic cells. Genital pore 0.57-0.66 mm from head end. Ovary turned back on itself in midregion of body, with its distal end directed forward on right side of proximal portion, measuring as a whole 0.4-0.5 X 0.24-0.3 mm. T h e germiduct arising from the distal end of the ovary gives off the genito-intestinal canal on the right and soon joins the duct from the vitelline reservoir; shell gland cells massed together at the point where the uterine duct bends back on itself. No eggs observed. Vagina subcylindrical, 27-38 X 10-15 densely lined with acute spines which are blunt-pointed at the bottom, opening at a distance of 0.12-0.2 mm behind intestinal bifurcation. In front of the vaginal pore is a transversely elongated oval pit, from the bottom of which arises a round-based peg appearing splintered at the tip. In front of this peg is a compact mass of lamellar muscle fibers, and behind it are numerous wavy muscle fibers, some of which extend backward along the vagina. Vaginal duct arising from posterior end of vagina, near which it is provided with a sphincter, emptying into anterior end of vitelline reservoir. Vitellaria commencing just posterior to intestinal bifurcation; vitelline reservoir 0.3-0.46x0.05-0.11 mm, entirely preovarian, with inflated stem and short lateral arms anteriorly. It is worth noting that this Indian species occurs in the same host species as it does in the Hawaiian waters. Unnithan stated that the vaginal duct opens into the fertilization chamber, but in our Hawaiian specimens it opens into the anterior end of the vitelline reservoir. The course of the vaginal duct as described by Unnithan is too unusual to be taken for granted.

Axinoides strongylurae n. sp.

FIGURE 121

Gills of Strongylura gigantea; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 178. (Based on six whole mounts.) Body slender, gradually tapering anteriorly; 2.5-5.0 mm long, 0.25-0.6 mm wide in front of cotylophore. Cotylophore 1.0-1.3 m m l°ng> oblique, with a row of 21-27 clamps; clamp skeleton 50-100 fi wide, consisting of two pairs of very slender, jointed, lateral sclerites, a pair of slender inner basal sclerites, and an unpaired median spring with anchor-shaped ends. Two pairs of prehaptoral larval hooklets present. Head 80-110 p wide. Oral suckers elliptical, septate, unarmed, 46-70 x 30-47 ¡1.. Pharynx oval to elliptical, 18-37 X 14-26 esophagus

i6o

DISCUSSION

narrow, without diverticles, bifurcating between genital pore and vagina. Intestinal crura simple at anterior part, with numerous short side branches elsewhere, terminating at different levels at base of cotylophore. Testes elliptical or irregularly ovoid, 21-35 number, in posterior interintestinal field from immediately behind ovary to near intestinal ends, arranged in two longitudinal rows. Vas deferens running straight forward, surrounded profusely by large prostate cells which are enclosed in a sheath of longitudinal muscle fibers between intestinal bifurcation and vitelline reservoir; its anterior tapering portion sinuous, leading into elongate elliptical pars prostatica immediately behind bulbus cirri. Cirrus forming an elliptical bulb of longitudinal muscle fibers basally but lined anteriorly with numerous pointed spines. Genital atrium comparatively wide, non-muscular, unarmed, with wide midventral opening at a distance of 0.33-0.8 mm from head end. Ovary tubular, 0.28-0.5 mm long as a whole, U-shaped proximally, with its long distal portion directed forward on right of median line; the germiduct turns inward at the point where the genito-intestinal duct is given off and opens into the vitelline reservoir, where the stem of the vitelline reservoir is somewhat attenuated. In the type the portion of the germiduct between this junction and the point where it bends back on itself is distended with yolk cells as if it were the direct continuation of the stem of the vitelline reservoir. Uterus midventral, running straight forward and opening into genital atrium ventral to bulbus cirri. No eggs observed. Vitellaria co-extensive with intestinal branches, commencing at level of vaginal pore or a little more posteriorly. Vitelline reservoir Y-shaped, with very short arms and a long stem (0.3-0.6 mm), entirely preovarian. Vagina subcylindrical, covered with very fine spines, with a peg at its opening, which lies dorsally just medial to the right intestinal limb. Vaginal duct very narrow, with a sphincter a little behind vagina, apparently emptying into junction of two vitelline arms. This species differs from the most closely related Axinoides bulbosus n. sp. from Belone platyura of Hawaii in possessing more numerous testes, a non-muscular genital atrium, a much more elongated ovary, and a submedian vaginal pore. The symmetrical bulbous swellings at the level of the genital pore, characteristic of A. bulbosus, have never been observed in the present species. The specific name refers to the specific name of the host.

KEY TO SPECIES OF

Axinoides FROM HAWAIIAN FISHES

Male and female genital pores separate; clamps 43-55; testes 30-62: A. diploporus Male and female genital pores common: 2 Body margin bulging out symmetrically at level of genital pore; clamps 44-57; testes 12-17: A. bulbosus Body margin never bulging out symmetrically at level of genital pore: 3 Body rather plump; clamps 62-75; testes over 40: A. kola Body slender; clamps 21-27; testes 21-35: A. strongylurae

Axinidae

Subfamily

122 HABITAT DESCRIPTION

DISCUSSION

123 HABITAT HOLOTYPE DESCRIPTION

ALLOPSEUDAXININAE

161

Yamaguti, 1963

Allopseudaxine katsuwonis (Ishii, 1936) Yamaguti, 1943

FIGURE

122

Gill of Katsuwonus pelamys; Hawaii. (Based on a single mount.) Body about 7 mm in total length, widest (0.95 mm) at the point where the opisthohaptor is attached and whence it tapers gradually toward the pointed anterior end. Opisthohaptor arcuate, 3.4 mm long along its convex margin; clamps 27 in number, each consisting of two pairs of simple arcuate arms of unequal length and a Ushaped median spring apparently perforated along median axis and provided with transversely striated alae as illustrated in my Systema Helminthum Vol. IV (PI. 59, Fig. 387b). Caudal lappet attached to posterior end of cotylophore, truncate conical, about 0.15 mm long; with two pairs of anchors; larger outer anchor 44-48 fi long, with very prominent guard about middle; smaller inner one similar in shape, 25.6 p long. Head 0.15 mm wide, with ventrosubterminal mouth aperture; oral suckers rounded, 35-46 X 37-39 /i, close to each other; pharynx elliptical, 58 X 35 not muscular; esophagus about 0.2 mm long; intestinal limbs with subdivided lateral branches, terminating close together near base of caudal lappet. Testes oval, occupying whole interintestinal field, pre-, para-, and postovarian; their exact number not made out (about 60 after Price, 1962). Genital pore 0.38 mm from head end. Genital atrium with a crown of 12, mostly apically bifid hooks about 46 ¡x long. Ovary tubular, folded back on itself medial to right intestinal limb in postequatorial region. Vitellaria profusely developed along intestine except for its anterior part, confluent in posttesticular region down to base of caudal lappet; vitelline reservoir Y-shaped, its stem sinistral to ovary, about 0.45 mm long. Eggs fusiform, 0.22-0.24 m m l° n & with filament about 60 fi long at each pole. Each vagina divided into a row of about a dozen transverse slits with sclerotized margins, extending along dorsolateral margin a little in front of anterior end of vitellaria. As compared with A. vagans (Ishii, 1936), this species possesses genital spines twice as long and nearly twice as many clamps.

Allopseudaxine yaito n. sp.

FIGURE

123

Gill of Euthynnus yaito (local name "kawakawa"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 179. (Based on three gravid specimens.) Body 7.8-9.0 mm in length, markedly tapered anteriorly, with maximum width of 2.4-3.0 mm at level of ovary. Opisthohaptor arcurate or semicircular, with 15-26 clamps characteristic of this genus, terminating in a conical hook-bearing appendage 0.16-0.27 mm long; of the terminal hooks the outer pair is 45-51 long and the inner 25-28 p long. Head rounded, 0.17-0.35 mm wide; mouth

162

DISCUSSION

124 HABITAT HOLOTYPE DESCRIPTION

cavity with thick wall of meridional muscle fibers; paired suckers small, oval, 3 7 - 6 0 X 4 5 - 5 0 N; pharynx pyriform, 5 5 - 7 0 X 3 2 - 5 0 ¡J.; esophagus simple, wide, bifurcating at about genital pore; intestinal limb with short inner and longer outer branches, right limb terminating at posterior end of body proper, left limb extending along opisthohaptor and reaching base of hook-bearing appendage. Testes comparatively large, 4 0 - 6 5 in number, arranged in two zigzag longitudinal rows in interintestinal field anterior and posterior to ovary, but in one row to left of ovary. Vas deferens narrow, running almost straight forward in median field. Cirrus bulbous, projecting into genital atrium, tipped with a crown of slender acicular spines. Genital atrium opening 0 . 4 - 0 . 7 mm from head end, bifurcal, provided inside its muscular ring with a crown of 13 terminally bifid or trifid spines. Proximal portion of ovary commencing at junction of middle with posterior third of body and ascending on right side of median line beyond equator, where it turns back on itself to give rise to germiduct on right side of stem of vitelline reservoir. Genito-intestinal canal crossing proximal portion of ovary on its ventral side and emptying into right intestinal limb at level of distal end of ovary. Shell gland complex posterior to junction of germiduct with vitelline reservoir. Uterus midventral, containing 4-15 fusiform eggs 0 . 1 8 - 0 . 2 mm long, 6 7 - 8 2 ¡x wide; rigid polar filament up to 0.2 mm long. Vaginae opening ventrosubmarginally at a distance of 0.9 mm from head end in the type, each divided into a longitudinal row of about ten transverse slit-like areolae with heavily cuticularized margins; each row is connected with the reticular vitelline ducts of its own side. Vitellaria co-extensive with intestine, commencing at a level posterior to intestinal bifurcation; anterior-most vitelline ducts of the two sides are connected by an arcuate transverse anastomosis; vitelline reservoir Yshaped, at level of middle portion of ovary. This species closely resembles Allopseudaxine macrova (Unnithan, 1 9 5 7 ) Yamaguti, 1963 from Euthynnus affinis of India (Trivandrum), but differs from it in the number of clamps and testes and in the egg size. In the Indian species the stem of the vitelline reservoir is stated and figured to be postovarian, but in the Hawaiian species it lies at the level of the middle portion of the ovary.

Allopseudaxinoides euthynni Yamaguti,

1965

FIGURE 1 2 4

Gill of Euthynnus yaito (local name "kawakawa"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 4 . (Based on 1 2 whole mounts.) Body large, 5 - 8 mm long from head end to tip of caudal appendage, markedly tapered in head and esophageal region, widest ( 2 . 9 - 5 . 5 m m ) a t opisthohaptor which extends obliquely along the posterior end of the body proper. Opisthohaptor unilateral,

Axinidae

163

bearing a row of 13-15 clamps and a prominent digitiform caudal appendage which is provided at its blunt end with two pairs of anchors; outer anchor 47-53 long, inner one 22-25 fClamp bivalved, 0.15-0.3 mm in diameter; median spring U-shaped, with rounded ends, consisting of sclerotized median piece and parallel-sided muscular flange which appears as a wing-like lateral extension of the median piece in optical section; dorsal valve of clamp is supported by a pair of long arcuate lateral sclerites meeting at tip of valve and curved medially at base; ventral valve is supported by a pair of apically slightly curved sclerites meeting in the median line and articulating at the base with dorsal sclerites at the angle where they bend medially. Beneath the apical ends of the ventral lateral sclerites are paired accessory sclerites which are contiguous to each other in the median line and articulate laterally with the ventral lateral sclerites. Head rounded, 0.13-0.17 mm wide; mouth ventroterminal. Paired oral suckers aseptate, 25-35 x 3°~~43 & pharynx pyriform, 40-70 X 30-43 sometimes protruding into buccal cavity; esophagus simple, 0.38-1.05 mm long, bifurcating a short distance posterior to genital atrium; intestinal limbs with short inner and longer outer branches, terminating in distal portion of opisthohaptor, right limb reaching to base of caudal appendage.

DISCUSSION

Testes up to about 20 in number, irregular in shape, extending in interintestinal field from pre-ovarian area to postovarian area, passing in one row on left side of ovary. Vas deferens narrow, almost straight dorsal to uterus. Cirrus forming a bulb surrounded by fine circular muscle fibers, produced forward into a cuticularized short cylinder tipped with a circular row of delicate spiniform structures which projects into the lumen of the genital atrium. Genital atrium spherical, 42-45 p. in diameter, with thick wall of radial muscle fibers, armed inside with a corona of over a dozen (14-24?) spines 20-25 l ° n § whose bifid tips are curved inwards; these spines are supported at the base by another corona of stumpy denticles. Genital pore midventral, 0.25-0.6 mm from head end. Ovary 1.3-1.8 X 0.15-0.4 mm, turned back on itself in midregion of body, with both ends directed backwards. Genito-intestinal duct crossing proximal and distal ends of ovary and opening into right intestinal limb. Uterus midventral; eggs elliptical, 0.12-0.2 mm long by 58-70 ¡>, wide, with polar filament 0.07-0.14 mm long at each pole. Vitellaria co-extensive with intestine and its branches. The longitudinal vitelline ducts of the two sides are united anteriorly across the median line dorsal to the esophagus, and behind this anastomosis is seen a network of anterior vitelline ducts as shown in Fig. 125A. Vitelline reservoir Y-shaped, its stem 0.4-0.6 mm long, and its right arm crossing ovary about its middle. Vaginae not detected in the type, but in the related Allopseudaxinoid.es vagans (Ishii, 1936) n. comb, rudimentary vaginae are seen just in front of the anterior end of vitellaria. This genus differs from Allopseudaxine Yamaguti, 1943 in the complete

164

absence or radimentation of vaginae and the presence of a pair of subapical accessory sclerites contiguous to each other in the median line and articulating laterally with the ventral lateral sclerites. In the latter respect, my original description and the figure (15B) are not very clear, so they are emended as above and Fig. 15B (1965) is replaced by Fig. 124B which shows the accessory sclerites more clearly in ventral view. The generic diagnosis of Allopseudaxinoides as given in the 1965 paper should be emended as follows so far as the vaginae, accessory sclerites, and the anterior commissures of the vitelline ducts are concerned: Vaginae absent or rudimentary. Accessory sclerites present beneath apices of ventral lateral sclerites. Vitellaria united anteriorly by reticular anastomosis of small vitelline ducts. For further details, see Pacific Science 19(1): 83-85.

125 HABITAT DESCRIPTION

DISCUSSION

Allopseudaxinoides vagans (Ishii, 1936) n. comb.

FIGURE

125

Gill of Katsuwonus pelamys; Hawaii. (Based on a single mount.) Body about 7 mm long, slender anteriorly but enlarged for the greater remaining part; cotylophore about 4.5 mm long along its straight margin provided with 14 clamps; clamp skeleton (Fig. 125A) similar to that of Allopseudaxinoides euthynni. Caudal appendage slender, about 0.3 mm long, bearing two pairs of anchors 49 ju. and 23 ¡x long respectively. Head 0.1 mm wide; oral sucker aseptate, 25 X 18 //.; pharynx elliptical, non-muscular, 46 X 23 ¡x; esophagus apparently bifurcating just posterior to genital pore; intestinal limb with subdivided lateral branches, terminating close together at posterior end of opisthohaptor. Testes distributed in the same manner as in Allopseudaxine katsuwonis and Allopseudaxinoides euthynni; their number could not be determined (30-35 after Price, 1962). Genital atrium provided inside with a crown of 12, apically bifid hooks (22 after Price, 1962) about 23 ¡¡l long. Bulbus cirri elongate pyriform, 23 X 14 ¡i, tipped with a bundle of several minute spines 9 ju. long. Ovary medial to right intestinal limb at level of vitelline reservoir. Egg shrunken, not measured. Vitellaria co-extensive with intestine except for its anterior and posterior ends; vitelline reservoir Y-shaped, stem 0.3 mm long. This species was transferred by Price (1962) to Allopseudaxine, but since the clamp skeleton possesses accessory sclerites similar to that of Allopseudaxinoides euthynni, it should be assigned to Allopseudaxinoides and not to Allopseudaxine in which the accessory sclerites are absent. In view of the fact that the accessory sclerites are present in one genus and absent in another very closely related genus, it seems that this structure is merely of generic importance.

Axinidae

Subfamily

126 HABITAT HOLOTYPE DESCRIPTION

MONAXININAE

165

Unnithan, 1957

Mlomonaxine carangoides Yamaguti, 1965

FIGURE

126

Gills of Carangoides sp.; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 15. (Based on nine whole mounts.) Body moderately large, wedge-shaped in outline, tapering anteriorly, widest (0.2-0.27 mm) at obliquely truncate posterior end, along which is attached a row of 40-50 clamps. Clamp skeleton up to 70-110 ¡x wide, of Microcotyle type, consisting of a Ushaped median piece without accessory apical pieces, two pairs of lateral sclerites, and a pair of curved basal rods. Head end truncate, 0.3-0.4 mm wide, with ventroterminal mouth aperture. Oral suckers elliptical, septate, 0.08-0.11 X 0.15-0.2 mm. Pharynx pyriform, 57-100 X 47-63 JU,; esophagus

0.3-0.5 mm long, with few side branches, bifurcating immediately behind genital atrium. Intestinal limbs with numerous, subdivided, outer branches and fewer, simpler, inner branches, not confluent posteriorly; left limb extending beyond right limb to near extreme left end of body. Testes rounded, very numerous, paved in one layer and occupying whole postovarian interintestinal field; under low power of magnification they appear like a single lobed organ subdivided by inner intestinal branches. Vas deferens winding regularly from one side of median line to the other among inner intestinal branches, convoluted behind intestinal bifurcation. No cirrus differentiated. Genital atrium reniform, 0.16-0.24 X 0.24-0.27 mm, provided with well-developed radial muscle fibers, armed inside with spines of four different types; ventral spines 3075 ¡x long, 34-40 in number, with straight shaft and claw-like point, arranged very close to one another in a transverse row intermingled dorsally at somewhat regular intervals with 14-16 shorter spines whose point is simple and whose shaft is curved out dorsally about the middle; of the lateral spines four lie transversely on each side at the male genital pore, and 20-22, similar in shape to those longer ventral spines and 50-63 /x long, are arranged in a gently curved row immediately lateral to the shorter (30-40 long), stouter claw-like, medial spines which are arranged in a dorsoventral row. Genital pore midventral, prebifureal, 0.380.5 mm from head end. Ovary equatorial, tubular, originating with or without enlargement, immediately in front of anterior-most testes, describing a double loop, with its distal end directed posteriomesad, measuring 0.5-0.7 X 0.6-0.9 mm as a whole. Genito-intestinal duct short, opening into right intestinal limb at level of ootype. Uterus midventral; eggs elliptical, about 0.17 X 0.07-0.075 mm, with long convoluted filament at posterior pole and a shorter, non-convoluted filament at opercular pole. Vitellaria commencing at a level halfway between intestinal bifurcation and level of

i66

DISCUSSION

Subfamily 127 HABITAT HOLOTYPE DESCRIPTION

vaginae, extending along intestinal branches; vitelline reservoir Y-shaped, overlapping ovary on its ventral side. Vaginae double, dorsolateral, symmetrical, opening a short distance behind intestinal bifurcation, 1.0-1.25 mm from head end; each opening provided densely with acicular spines, surrounded by extremely finely denticulated cuticle, with a conspicuous ventral lateral depression immediately in front; at the bottom of this pit is a mass of over a dozen minute conical teeth representing an accessory vaginal armature. This accessory vagina is connected with the vagina proper by a narrow duct. Vaginal ducts running posteromesad, each probably joining anterior part of collecting vitelline duct of its own side. Longitudinal collecting vitelline duct was seen filled with sperm in one paratype. This genus bears a superficial resemblance to Monaxine Unnithan, 1 9 5 7 , but it differs fundamentally in the vagina being paired and in having symmetrical, ventrolateral, prevaginal depressions, each of which is provided at the bottom with a small dense mass of conical teeth. These two characters are sufficient to justify the erection of a new genus, for which the name Allomonaxine was proposed in 1965.

HETERAXININAE

Unnithan, 1 9 5 7

Heteraxinoides caprodontis n. sp.

FIGURE 1 2 7

Gills of Caprodon schlegelii; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 180. (Based on 1 3 whole mounts.) Body flattened, asymmetrically conical, 1 . 3 5 - 3 . 8 mm long, up to 0 . 3 7 - 1 . 2 5 mm wide at posterior end of body proper. Opisthohaptor often extending continuously a little forward around posterior comer of body proper, but usually with two unequal rows of similar clamps (3-6 clamps on shorter side 0 . 1 5 - 0 . 3 5 mm long, 1 3 - 2 7 clamps on longer side 0 . 4 8 - 1 . 7 5 mm long); total number of clamps varying from 17 to 33. Clamp skeleton exactly of Microcotyle type; lateral arm unjointed; median spring with a slender accessory piece on tip of shorter prong. Neither prehaptoral anchors nor caudal appendage. Head rather truncate, 8 0 - 1 2 0 ¡x wide at base, with three (one median and two submedian) conspicuous masses of head organs along frontal margin. Mouth aperture ventrosubterminal. Oral sucker muscular, aseptate, 2 8 - 4 4 x 35—51 ¡i. Pharynx pyriform, weakly muscular, 3 0 - 4 2 X 2 3 - 4 2 ¡i. Esophagus short, not diverticulate, bifurcating dorsal to genital atrium. Intestinal limbs with short inner and longer outer branches, terminating close together behind posterior-most testis at posterior corner of body proper. Testes subglobular, 5-11 in number, arranged irregularly, usually in a zigzag row, in postovarian interintestinal field. Vas deferens median,

Axinidae

167

more or less winding between ovary and intestinal bifurcation; neither pars prostatica nor prostatic cells. A very short ejaculatory duct may be differentiated between vas deferens and cirrus. Cirrus consisting of basal bulb 19 p in diameter and a crown of about a dozen pointed spines 7-13 ft. long and projecting into genital atrium. Genital atrium bifurcal, provided mainly with radial muscle fibers, 2 7 - 3 9 x provided inside with five conical lobes and a crown of minute submarginal spines, the size and number of which could not be determined. Common genital pore 1 1 6 - 1 6 0 ¡x from head end. Ovary curved like an interrogation mark, 0 . 3 5 - 0 . 8 X 0 . 1 5 - 0 . 2 5 mm, postequatorial, with both ends directed backward. The descending germiduct turns to the right after joining the round seminal receptacle to give off genito-intestinal duct which opens into the right intestinal limb, so that the distal portion of the germiduct appears like a direct continuation of the genito-intestinal canal. Ootype anterosinistral to proximal end of ovary. No eggs observed. No definite vagina. In all the specimens examined there is a middorsal group of two or three minute pointed spines immediately behind the intestinal bifurcation. This appears to indicate the residue of an atrophied vagina. Vitellaria co-extensive with intestinal branches; stem of vitelline reservoir markedly curved posteriorly, 0 . 2 5 - 0 . 6 mm long. DISCUSSION

Subfamily 128 HABITAT HOLOTYPE DESCRIPTION

This species differs from the most closely related Heteraxinoides triangularis (Goto, 1894) from Anthias schlegeli of Japan in the number of testes and clamps. In Goto's species the testes are about 12 in number and the clamps on the longer side are 36.

SIBITREMATINAE

Yamaguti,

1966

Sibitrema poonui Yamaguti, 1966

FIGURE 1 2 8

Gill of Parathunnus sibi (local name "poonui") and Neothunnus macropterus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 5 0 . (Based on two gravid specimens.) Body 1 9 . 2 mm in total length, distinctly divided into three regions: body proper, haptoral stalk, and haptoral region. Body proper slender, lanceolate, tapered anteriorly, with a pair of compact eyespots, constricted behind, 11.7 mm long by 1.4 mm wide in posterior part where ovary is situated. Haptoral stalk fusiform, 4.3 X 0.45 mm, containing intestine and vitelline gland alone, attenuated posteriorly and then gradually enlarged to pass into haptoral region which is spatulate, produced posteriorly into a conical terminal appendage. This appendage is 0.2 mm long by 0.2 mm wide at the base and bears on the ventral surface of its apex two pairs of larval hooklets of different size; outer pair 46 ¡x long, inner pair 21 /t long, both with a very prominent

i68

guard and a well-curved blade. On the left border of the haptoral region is a single longitudinal row (about 3 mm long) of 48 clamps 50-90 p. in transverse diameter. Clamp skeleton consisting of a pair of inner basal processes, two pairs of lateral arms, a pair of accessory pieces meeting in median line, and a stout median spring, one end of which is anchorshaped, while the other end is surmounted by a Y-shaped apical piece. Mouth cavity wide, opening ventroterminally, with oval paired suckers (46 X 23 p) laterally and a globular, weakly muscular, median pharynx at its bottom; esophagus simple, 1.45 mm long, contracted at beginning but soon enlarged to width of 0.15 mm, bifurcating immediately behind genital pore. Intestinal limbs with numerous short inner and longer outer branches; right limb terminating at base of terminal appendage, left one 0.5 mm further in front. Testes rounded, 75 in total number, pre-, para-, and postovarian; preovarian testes in two parallel submedian rows of 15 or 16 each; paraovarian testes 18 or 19, in two longitudinal rows immediately outside of ovarian loop; behind the ovary there are only several testes in the median field. Vas deferens median, dorsal to uterus; bulbus cirri weakly muscular, 70 ¡x in diameter, situated just ventral to intestinal bifurcation. Cirrus consisting of several sharp-pointed spines which are 35 p. long and bundled together immediately in front of atrial crown of 12 spines; these spines are 51-56 /x in length including base which forms a ring of 12 backwardly directed prongs; the shaft of each spine is straight, but the apex is curved inward and bifid at the tip. This crown of spines is enclosed in a very thick-walled atrial bulb of radial muscle fibers, which in turn is enclosed in a membranous genital atrium. Genital pore midventral, at anterior end of genital atrium, 1.45 mm from head end.

DISCUSSION

Ovary tubular, bent back on itself on right side of median line, 3.15 mm long as a whole, swollen (0.3 mm wide) at postequatorial proximal end in form of a recurved mass and at distal end in form of a club, from the posterior end of which the germiduct arises. Genito-intestinal canal arising from near middle of germiduct, running obliquely forward across proximal portion of ovary ventrally to empty into right intestinal limb. Vitelline follicles small, co-extensive with intestinal branches, commencing a little behind vaginae; vitelline reservoir Y-shaped, to left of distal end of ovary, connected with germiduct by a narrow descending median stem 0.15 mm long. Uterus straight, midventral, containing a few eggs; eggs fusiform, 0.23-0.25 X 0.07-0.09 mm, with filament 40-60 ¡i long at each pole. Vaginae symmetrical, about 0.5 mm long, divided into a series of several (8-14) areolae, situated laterally about halfway between genital pore and anterior end of vitellaria. This genus closely resembles Allopseudaxine Yamaguti, 1943 in internal anatomy, but it differs markedly in general body shape and, what is more important, in the structure of the clamp. A new subfamily Sibitrematinae was proposed for its reception in 1966.

Axinidae

Subfamily

129 HABITAT HOLOTYPE DESCRIPTION

169

CYPSELUROBRANCHITREMATINAE Yamaguti, 1966

Cypselurobranchitrema

spilonotopteri Yamaguti, 1966

FIGURE 129

Gill of Cypselurus spilonotopterus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 51. (Based on four whole mounts.) Body 7-10 mm in total length, enlarged laterally up to 2.3-3.5 m m midregion; anterior third abruptly tapered toward head end which is 0.2-0.4 mm wide at the level of the oral sucker; posterior third occupied by large cotylophore which is 2.44.2 mm long by 2.8-3.8 mm wide and extends on the ventral side from behind the posterior end of the ovary to a considerable distance back of the posterior end of the body proper. In the type this cotylophore begins in the midventral region at the level of the junction of the middle with the posterior third of the entire body with a smooth semicircular fold 1.2 mm wide, which is followed by a twisted fan-shaped body fold fringed with a semicircular row of 18 or 19 long-stalked clamps. For convenience of reference the clamps are numbered from the front backwards; the first clamp next to the semicircular fold is the smallest (about 0.2 mm in diameter), rather short-stalked, the 12th may be slightly out of the row of other clamps, the 14th to 16th are the largest (up to 0.45 mm in diameter), with longer stalks, and the last, 18th (19th in one paratype), attached to the right posterior end of the body proper, is provided on the proximal anterior margin of its stalk with a blunt-conical or subcylindrical caudal appendage 0.15-0.16 mm long. This appendage is armed in the type with a small guarded hook 35 ¡i long and two dissimilar subapical hooks, one of which is 77 p long and guarded like the apical hook, but the other is simple, falcate, and 37 ¡t. long lineally. In the paratypes either the guarded subapical or the falcate hook is absent. Clamp skeleton 0.180.46 mm in diameter, consisting of an arcuate median spring provided laterally with transversely striated muscular wings and two pairs of curved lateral arms articulating with each other, of which the smaller pair articulates at the distal end with a small, A-shaped accessory sclerite. Head end rounded; mouth aperture wide, subterminal; oral suckers paired, muscular, septate, 53-81 X 65-93 pharynx oval, weakly muscular, 116 X 98 p. in the type; esophagus simple, 0.5-0.7 mm long, bifurcating a little behind genital pore. It is not certain whether the intestinal limbs are confluent posteriorly, or not; there are wide anterolaterally directed diverticles on each side anteriorly, the remaining greater part with few short inner and numerous longer, subdivided, outer branches accompanied by vitellaria and pigment cells; posterior outer branches extending into basal portion of clamp stalks. Testes rounded, about 50 in total number, arranged in two zigzag longitudinal rows, one on each side of median line; anterior ones pre-

170

DISCUSSION

Family 130 HABITAT HOLOTYPE

ovarian, posterior ones paraovarian, some between ovarian limbs. Vas deferens straight or gently undulating in median field, surrounded at its distal end by prostate cells; no pars prostatica differentiated. A distinct globular bulb of very fine muscle fibers is developed around the somewhat swollen distal end of the ejaculatory duct. Cirrus represented by a cylindrical group of very fine acicular spines, enclosed basally in a crown of 18 hooks, which in turn is enclosed in the atrial bulb with thick walls of radial muscle fibers. The hooks are fused near the base, and their simple attenuated points are curved inwards. The thick-walled atrial bulb is 51-80 ¡1. in outside diameter and is enclosed entirely in the genital atrium with a membranous wall. Genital pore midventral, immediately in front of the above mentioned thick-walled atrial bulb, 0.5-0.7 mm from head end. Ovary inverted U-shaped, 2.35 mm long by 0.4 mm wide as a whole in the type, enlarged at proximal end to an elongate compact mass, situated to right of median line in middle third of body. Genito-intestinal duct arising from germiduct just before the latter unites with the stem of the vitelline reservoir. Ootype posterosinistral to this genital junction. Uterus proper alongside vas deferens, opening into genital atrium ventral to male duct. Mature eggs elongate oval, 0 . 2 5 - 0 . 2 6 X 0 . 1 1 - 0 . 1 5 mm, with a rigid filament at each pole; anterior filament 0 . 1 9 - 0 . 2 6 mm long, posterior filament 0 . 1 2 - 0 . 2 mm long, slightly enlarged at tip. Genito-intestinal duct running straight obliquely forward and emptying into right intestinal limb, with distinct accompanying cells. Vaginae indistinct in the type, but present on each side in form of a ventrosubmarginal longitudinal row of several rudimentary areolae just behind level of symmetrical excretory pores in one of the paratypes. Vitelline follicles small, co-extensive with intestinal limbs and their branches; vitelline reservoir Y-shaped, with short arms. Excretory pores symmetrical, dorsosubmarginal, at about level of genital pore or a little posterior to it. This genus resembles AUopseudaxinoides Yamaguti, 1 9 6 5 in general internal anatomy and in the structure of the clamp skeleton, but differs from it in the arrangement of the clamps and in possessing septate oral suckers but no reticular anastomosis of the anterior-most vitelline ducts. I preferred, therefore, to separate this genus as representing a new subfamily, Cypseluribranchitrematinae, and to place it near Allopseudaxininae Yamaguti, 1963.

CEMOCOTYLIDAE Yamaguti, 1963 Cemocotylella carangis n. sp. Gill of Caranx helvolus (local name "black ulua"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 8 1 .

FIGURE 1 3 0

Cemocotylidae

DESCRIPTION

171

(Based on 20 whole mounts.) Body lanceolate, tapering anteriorly, 2.75.3 mm in total length, with maximum width of 0.3-0.8 mm in region of uterus filled with eggs. Opisthohaptor asymmetrical, with a terminal appendage bearing three pairs of anchors; largest outer anchor 41-56 ¡1 long from tip of dorsal root to height of curve of blade, 16-30 ¡x from tip of dorsal root to tip of ventral root; smallest middle anchor slender, 18-28 ft long, apparently recurved at tip; inner anchor with a straight long shaft and a small recurved point, 28-35 P l° n §- Clamps 21-36 in total number, approximately of Microcotyle type though provided with a complex 4-pronged accessory piece on anchor-like tip of shorter arm of median spring, up to 46-58 fi wide at base, 16-25 l° n g row, 4-8 in short row; clamps in long row decreasing in size anteriorly, some of posterior-most also smaller than those in middle region of row; latter clamps with asymmetrical lateral sclerites, of which the outer are definitely longer than the inner; clamps in short row nearly uniform in size and shape. No clamps of so-called "muzzle" type. Head 0.11-0.22 mm wide, abruptly tapered anteriorly into a blunt point, with a ring-shaped compact head organ along each sloping lateral margin and another transversely elongated band-like head organ immediately behind oral sucker and uniting ventral to pharynx; their gland cells irregular in shape, extending longitudinally on each side of esophagus. Oral sucker rounded, muscular, 28-42 X 18-35 # pharynx not muscular, rounded, 35-51 n in diameter. Esophagus usually simple, 0.1-0.2 mm long, with a pair of anterolaterally directed side branches near its anterior end in the type, bifurcating dorsal to genital pore. Intestinal limbs with short outer diverticula except at their posterior ends extending into opisthohaptor, where they end blindly close together. Testes irregular in shape, 20-42 in number, arranged in two to four irregular longitudinal rows in postovarian interintestinal fields, without reaching cecal ends. Vas deferens up to 25 p wide, almost straight, middorsal, obscured by uterus in all gravid specimens; ejaculatory duct swollen proximally, provided throughout with circular muscle fibers. Cirrus consisting of a basal bulb of circular muscle fibers and a sharp-pointed terminal spine 46-58 fi long and 9-14 ¡x wide at its broad base, situated longitudinally with its point directed toward genital pore. Genital bulb muscular, 18-30 X 21-30 ¡x. Common genital pore unarmed, ventral to intestinal bifurcation. Ovary tubular, slender, looped, 0.2-0.45 m m l ° n § lineally. Genitointestinal duct comparatively short, muscular, emptying into right intestinal limb on the right of origin of germiduct. Uterus distended almost throughout its length; occupying whole interintestinal field between ovary and intestinal bifurcation; eggs fusiform, 160-200 X 40-53 ju. in life; polar filament 80-130 p. long. Vitellaria comparatively poorly developed along intestine, leaving both ends of latter free, apparently not confluent posteriorly; vitelline reservoir Y-shaped; its stem 0.15-0.22 mm long, extending longitudinally in ovarian zone. Neither vagina nor seminal receptacle.

172

DISCUSSION

Family Subfamily

151 HABITAT DESCRIPTION

132 HABITAT HOLOTYPE DESCRIPTION

This species differs notably from the most closely related Cemocotylella elongata (Meserve, 19 38) Price, 1962 in the eggs bearing a filament at each pole. In C. elongata there is a filament at the anterior end alone, a varying number of the clamps are said to be of the "muzzle" type, and the vitellaria are confluent posterior to the testes. This "muzzle" type of the clamp skeleton, however, appears to me to be not muzzle-like but merely asymmetrical, as in the present species.

GASTROCOTYLIDAE Price, 1943 GASTROCOTYLINAE

Sproston, 1946

Gastrocotyle trachuri van Beneden et Hesse, 1863

FIGURE 1 3 1

Gills of Trachurops crumenophthalmus; Hawaii. (Based on four non-gravid specimens.) Body 1.3-2.2 X 0.48-0.66 mm. Cotylophore 0.7-1.3 mm long, with 21-25 c l am P s > the skeleton of which is exactly same asfiguredby me in 1938 (PI. VI, Fig. 37). Caudal appendage trapezoidal, 50-100 ¡x long; outer pair of anchors 46-56 ¡¡., inner pair 1826 fi, middle pair 11-16 jx. Oral sucker oval, 18-23 X 14-16 /*.; pharynx bulbous, 23-30 X 16-23 pi esophagus 90-140 bifurcating at about level of genital pore; ceca with side branches, united posteriorly behind testes. Testes several (exact number not discerned), postovarian, near posterior extremity. Genital atrium with a crown of 12 spines which are 25-26 ¡I long, each having a simple, slightly curved point. Genital pore 0.15-0.2 mm from conical head end. Ovary turned back on itself with two ends directed backward, extending along vitelline reservoir on its ventral or dorsal side. Shell gland cells rosette-shaped, immediately in front of anterior-most testis. No eggs observed. Vitellaria co-extensive with intestine; vitelline reservoir 0.20.35 mm long, at about middle of body region bearing cotylophore.

Pseudaxine decapteri n. sp.

FIGURE 1 3 2

Gills of Decapterus pinnulatus (type host, local name "opelu"), D. maruadsi, Caranx mate and Trachurops crumenophthalmus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 182. (Based on 21 whole mounts.) Body lanceolate, 1.45-4.9 m m l°ng> up to 0.36-1.5 mm wide at level of midregion or a little more posterior. Opisthohaptor unilateral, hatchet-shaped, 0.6-2.2 mm long, with a row of 16-44 clamps 27-55 f wide; clamps with flattened, paired, accessory pieces; median spring with paired wing-like expansion at one end and anchorshaped extension at the other end; lateral arms unjointed; basal piece

Gastiocotylidae

173

flattened and applied to transversely striated wall of valve and not projecting mesad into lumen between two clamp valves. Haptoral appendage slightly tapering toward its truncate end, 0.065-0.4 mm long, with two pairs of hooks, of which the longer pair, 25-37 ¡x long, lies about the middle, and the other, 7.5-14 p long, at the tip. Head 0.09-0.12 mm; mouth wide, surmounted dorsally by a blunt-conical lobe. Oral sucker 18-40 p in diameter; pharynx pyriform, 25-53 X 22-43 esophagus simple, 0.05-0.4 mm long; intestinal limbs with numerous side branches, terminating at posterior end of body, with their ends directed toward haptoral appendage and their terminal branches reaching to near base of clamps. Testes large, 6-20 in number, arranged in a zigzag row in one layer and occupying greater part of interintestinal field at posterior two thirds of body. Vas deferens thin-walled, with sperm, winding dorsal to uterus; its narrow distal portion provided with fine circular and longitudinal muscle fibers and surrounded by large, rounded prostatic cells, though not differentiated into typical pars prostatica. The proximal portion of the cirrus forms a spherical bulb (bulbus cirri) of apparently tangled muscle fibers; the distal portion of the cirrus forms a cuticular cylinder. Genital atrium 27-51 ¡J. wide, consisting of short radial muscle fibers enclosed in a limiting membrane, connected with above mentioned bulbus cirri by a ring of circular muscle fibers, in which the basal portions of about 12 or more atrial hooks are imbedded; the longer distal portions of the hooks project into the lumen of the genital atrium. The atrial hooks which are 20-30 /a long (including base 7-9 ¡¡, long), with their points recurved toward the center of the atrial lumen, are arranged in a complete circle. Common genital pore 0.17-0.38 mm from head end, just behind intestinal bifurcation.

DISCUSSION

Ovary 0.2-1.0 mm long as a whole, 0.1-0.32 mm in transverse diameter, looped at junction of anterior with middle third of body, with its two ends directed backward. The germiduct arising from the right distal end of the ovary gives off the genito-intestinal canal after crossing the proximal portion of the ovary ventrally, and then joins the stem of the vitelline reservoir. Genito-intestinal canal obliquely crossing distal portion of ovary. Uterus ventral to vas deferens and male terminalia, apparently opening into genital atrium near its common pore. Eggs elliptical or fusiform, 0.18-0.27 X 0.065-0.08 mm, with filament up to 0.25 mm long at each end. Vitellaria co-extensive with intestine and its branches; vitelline reservoir Y-shaped, largely overlapping ovary. Vagina of each side divided into longitudinal row of 5-13 transversely elongated cuticular pits, beginning just behind level of genital pore. Vaginal ducts of two sides running medioposteriorly to join together. This species differs distinctly from Pseudaxine trachuri Parana et Perugia, 1890 from Caranx trachurus in the genital pore being a little anterior to the intestinal bifurcation. In P. trachuri the genital pore lies a short distance posterior to the intestinal bifurcation. The peculiar structure of the vagina must have been overlooked by Parona and Perugia and sub-

174

sequent authors because it is recognizable in well preserved specimens alone. It is to be noted that the senile specimens which are widest at the testicular level bulge out laterally on the same side as the caudal appendage to give the body an appearance very different from that of the young adult. In such specimens the vitellaria are very strongly developed in the testicular region, whereas the testes show degenerating vesicular structure.

133 HABITAT HOLOTYPE DESCRIPTION

Pseudochauhanea

sphyraenae Yamaguti, 1965

FIGURE 133

Gill of Sphyraena barracuda; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 16. (Based on five whole mounts.) Body lanceolate, tapered anteriorly from level of vagina, usually 4.45-5.8 mm long, but may be up to 10 mm long when completely relaxed, with maximum breadth of 0.32-1.4 mm at posttesticular level. Opisthohaptor without terminal anchors, asymmetrical, without attenuated stalk as seen in Chauhanea madrasensis Ramalingam, 1953; clamps unequal, with skeleton of Gastrocotyle type, 28-50 on the right, 25-37 o n the left, making a total of 58-87. Paired prohaptoral suckers elliptical, muscular, with several septa, 7 2 - 1 1 2 X 37-60 ¡X. Head rounded, truncate at apex, with subterminal mouth opening. Pharynx globular, 37-58 X 35-50 ¡x; esophagus 0.83-2.0 mm long, giving off numerous simple or subdivided side branches at right angles, bifurcating just in front of vaginal pore, anterior-most esophageal branches apparently rosette-shaped. Intestinal limbs with numerous subdivided branches laterally; each may give off posteriorly two secondary limbs which are also provided with side branches and run backward parallel to main limbs; these limbs are not accompanied by the vitellaria posteriorly and may or may not reach the posterior end of the opisthohaptor. Testes rounded, 70-100 in number, pre-, para-, and postovarian, commencing a certain distance (0.5 mm in the type 4.45 mm long) behind vaginal pore and terminating at level of anterior-most clamp. Distal portion of vas deferens running ventral to esophagus, strongly winding and provided with thick wall of circular muscles. Cirrus pouch fusiform, 90160 X 30-45 ¡x, provided outside with well-developed longitudinal muscles, oblique to body axis on right side of esophagus; cirrus unarmed, opening into relatively wide genital atrium which, in turn, opens ventrally close to right margin of body at a distance of 0.36-0.84 mm from head end. In the region of the genital pore the body bulges out a little as shown in the figure. Ovary with irregular outline, confined to middle third of body on right side of median line medial to right intestinal limb, commencing with a compact mass 0.18-0.2 mm wide and ascending for a distance of 0.86-1.4 mm and then descending alongside ascending portion, giving off germiduct just in front of compact proximal mass. Genito-intestinal duct crossing distal end of ovary ventrally, emptying into right intestinal limb.

Gastrocotylidae

DISCUSSION

134

HABITAT DESCRIPTION

175

Uterus midventral, finally running alongside cirrus pouch and opening into genital atrium near its margin. Eggs greatly elongated, 220-230 X 40 X j y with both ends produced into filaments 1 7 0 - 2 5 0 /t long. Vagina bulbous, about 0.11 mm in diameter in the type, opening midventrally just behind intestinal bifurcation, 0.95-2.4 mm from head end; vaginal duct could not be traced backwardly. A pair of narrow symmetrical ducts arising from base of vagina, each provided with a sphincter at distal end, probably united with vitelline duct passing nearby. Vitellaria commencing on each side at level of intestinal bifurcation, leaving posterior ends of intestinal limbs free; vitelline reservoir Y-shaped. This species differs from Chauhanea madrasensis Ramalingam, 1953 from Sphyraena acutipinnis in that the body lacks the haptoral stalk and the septate anterior suckers while it has a longer esophagus and a larger number of testes and the vagina is in a postbifural position. Ramalingam states that the vagina is on the left side, just beneath and parallel to the short unarmed cirrus, and that the vaginal pore is fringed with minute teeth-like spines. This entirely different location of the vagina and the difference in the body shape justify the creation of a new genus, for which the name Pseudochauhatiea was proposed in 1965.

Neothoracocotyle acanthocybii (Meserve, 1938) Hargis, 1956 Syn. Gotocotyla acanthocybii Meserve, 1938

FIGURE 1 3 4

Gills of Acanthocybium solandri; Hawaii. (Based on 18 whole mounts.) Body very much elongated, tapering anteriorly, provided with trapezoid, hook-bearing, caudal appendage at rounded posterior end, 1 2 - 1 6 mm in length, with maximum width of 0.9-1.7 mm at a level anterior to origin of cotylophore. Cotylophores extending one on each side over half the total length of body, unequal in length, bearing 1 5 2 - 2 6 8 pedunculate clamps, of which 8 5 - 1 3 0 are on the longer cotylophore and 8 0 - 1 4 0 on the shorter cotylophore. Except for poorly developed anterior clamps, the chitinous skeleton of clamp is 60-80 p wide and consists of a middle spring bifid at each end, a pair of basal pieces, two pairs of arcuate lateral sclerites, and paired apical accessory sclerites. On the posterior clamp valve there are three or four ribs on each side of median spring. Caudal appendage 0 . 1 5 - 0 . 2 7 mm long, with a pair of anchors 4 7 - 6 5 ¿1 long at its truncate apex. Mouth subterminal; oral sucker ovoid, 35-55 X 5 0 - 6 3 fi, aseptate, unarmed. Pharynx pyriform, 4 2 - 6 3 X 30-60 /i; esophagus 1 . 9 - 2 . 6 mm long, with several lateral branches on each side posteriorly. Intestinal limbs with numerous shorter inner and longer outer branches, united posteriorly just anterior to base of caudal appendage. Testes 5 5 - 1 0 0 in number, irregular in outline and arrangement, occupying whole postovarian interintestinal field. Vas deferens more or less winding in median field dorsal to uterus. No cirrus differentiated. Genital

176

DISCUSSION

Subfamily 135 HABITAT HOLOTYPE DESCRIPTION

atrium a large globular cavity, armed with very numerous acicular spines, the number and length of which could not be discerned because of their overlapping position. Genital pore ventral to esophagus at a distance of 0.6-1.0 mm from head end. Ovary inverted U-shaped, 2.5-3.5 m m l° n & originating in front of testicular area with distinct enlargement; its ascending limb pressed against descending limb; its anterior turning point may be anterior or posterior to origin of longer cotylophore or just level with it; distal descending limb lies on the right or left side of the median line, but usually on the same side as the longer cotylophore; the whole organ extends from the posterior half of the middle third of the body to the anterior half of the posterior third. Genito-intestinal duct running forward along distal portion of ovary on its medial side and opening into right intestine. Vitellaria co-extensive with intestinal branches, very close to each other at intestinal bifurcation, confluent posteriorly. Vitelline reservoir Y-shaped, 0.4-0.9 mm long; common stem relatively short. Eggs elliptical, 0.170.27 X 0.06-0.12 mm, with stiff polar filament 0.1-0.17 mm long at each end. Vagina middorsal, slit-like, a little in front of anterior end of vitellaria. This species was assigned by Hargis ( 1 9 5 6 ) to Neothoracocotyle, but it differs markedly from the type species of this genus in the extremely long ovary which extends as far forward as the anterior end of the longer cotylophore or beyond it, in the esophagus possessing lateral branches, and in the caudal lappet bearing one pair of anchors instead of two pairs, etc.

AREOTESTINAE

Yamaguti,

1965

Areotestis sibi Yamaguti, 1965

FIGURE I 3 5

Gill of Parathunnus sibi (type host), Neothunnus macropterus, and Thunnus alalonga; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 17. (Based on 16 whole mounts.) Body proper widened from level of anterior end of ovary to cotylophore, 1 1 - 2 5 X 4 . 5 - 1 6 mm, abruptly narrowed anterior to ovary and gradually tapering toward head which is 0 . 1 1 0.21 mm in diameter. There are 63-105 clamps arranged in an oblique row along entire posterior margin of body proper, whose posterior extremity is prolonged into a conical appendage bearing two pairs of hooks; clamp skeleton consisting of two pairs of arcuate lateral arms, a pair of short basal arms, a pair of accessory sclerites, and a median spring; longer prong of median spring anchor-shaped, but shorter prong slightly truncate apically and bearing simple, paired and terminally bifid, unpaired, poorly sclerotized, apical pieces just beneath the simple accessory sclerites. Of the caudal hooks the outer pair is 40-54 /i long and the inner pair 22-30 ¡x

Gastiocotylidae

DISCUSSION

177

long, both with a very prominent guard and a long well-curved blade. Head end usually rounded, with wide mouth aperture ventrally; at the bottom of the buccal cavity is a pair of comparatively small, aseptate, muscular suckers 20-33 f- by 27-50 ¡¡.. Pharynx oval, 45-60 x 35-50 p.; esophagus simple, 0.06-1.6 mm long, bifurcating a little behind genital pore; intestinal limbs simple anteriorly, sooner or later giving diverticles which unite with one another and form network extending throughout enlarged portion of body proper, enclosing variable number of testes in the meshes. Testes rounded, separated into 70-170 flat areolae, very irregular in size and outline, commencing at junction of anterior with middle third of body; each areola comprising 1-20 testes. Vas deferens strongly twisted posteriorly when distended with sperm, running in interintestinal field dorsal to uterus but more loosely winding anteriorly and differentiated into a sigmoid pars prostatica surrounded by prostate cells a short distance posterior to genital pore. Ejaculatory duct narrow, winding. Cirrus pouch funnel-shaped, containing bulbus cirri at its widest anterior portion, continued into genital atrium; cirrus consisting of a basal bulb 45-50 ¡¡. in diameter and an apical bundle of elongate cuticular shingles projecting into genital atrium. The structure and number of the shingles could not be discerned, because they are massed tightly together. They appear to arise from the anterior border of the truncate conical, membranous extension of the bulbus cirri. Genital atrium 65-93 in diameter, provided with thick wall of circular muscle fibers, provided inside with a crown of 13-18 hooks which measure 40-55 ¡i in length including the cylindrical base 1 4 19 ft, long, each being bifid at the incurved tip. Genital pore ventral to esophagus, 0.36-0.75 mm from head end. Ovary tubular, arising from posterior end of interintestinal field at anterior end of posterior third of body in form of a compact V-shaped mass of very small primordial germ cells, then extending forward just medial to left intestinal limb, turning back on itself at about midbody and descending along medial side of ascending portion; as a whole the ovary measures 2.6-6.5 m m length and 0.12-0.6 mm in maximum width. Genito-intestinal duct frequently forming a rounded or elliptical seminal receptacle 12-25 P diameter near its origin from germiduct, opening into left intestinal limb, usually at a level a little anterior to its origin. Eggs fusiform, thick-shelled, 175-265 X 70-120 ¡J, in mounted condition, produced at each end into rigid process which is 70-200 ¡x long and may or may not terminate in a disc 8-25 p in diameter. Vagina entirely lacking. Vitellaria completely co-extensive with intestine and its network; their rudimentary follicles commencing along esophagus at varying levels posterior to genital atrium; vitelline reservoir Y-shaped, its stem 0.45-1.3 mm long, immediately dextral to distal portion of ovary. This obviously gastrocotylid species cannot be assigned to any known genus on account of the absence of a vagina and the peculiar arrangement of the testes. A new genus and a new subfamily, referring to the areolate

178

testes, were therefore proposed for its reception. The original spelling of the subfamily name should be emended to read Areotestinae, because testis is genitive singular. For the diagnosis of the subfamily and further details, see Pacific Science 19(1): 8 9 - 9 1 . Family Subfamily 136 HABITAT HOLOTYPE DESCRIPTION

MICROCOTYLIDAE Taschenberg, 1879 MICROCOTYLINAE

Monticelli, 1892

Microcotyle bothi n. sp.

FIGURE 1 3 6

Gill of Bothns mancus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 183. (Based on 33 whole mounts.) Body elongate, 3.8-7.9 mm in total length, with maximum width of 0.68-1.3 mm in ovariotesticular region. Opisthohaptor with a total of 4 5 - 6 5 stalked clamps; clamp skeleton of Microcotyle type, 7 0 - 1 0 0 fi. wide. Oral sucker with incipient septum, unarmed, 50-116 X 50-100 p. Pharynx 75-128 X 75-140 p; esophagus simple, bi-

DISCUSSION

137 HABITAT HOLOTYPE

furcating immediately posterior to genital pore; intestinal limbs with short side branches, terminating at different levels in opisthohaptor. Testes rounded or irregular in shape, 18-48 in number, occupying greater part of postovarian interintestinal field. Vas deferens winding in median field. On each side of the vas deferens there are many prostatic cells, but no pars prostatica is differentiated. Cirrus bulb rudimentary. Genital atrium scyphiform, spined, with well-developed muscle fibers, with its lumen 60-120 /t in anteroposterior diameter, 70-160 /a in transverse diameter. Genital pore ventromedian, 0.3-0.56 mm from head end. Ovary tubular, irregularly looped, measuring 0.4-1.0 X 0.18-0.42 mm as a whole, situated in middle third of body, with both ends directed backward. Genito-intestinal canal short, opening into right intestinal limb at level of distal end of ovary. Shell gland complex dorsal to posterior part of stem of vitelline reservoir. Uterus ventromedian; eggs elliptical, 200280 n long by 70-100 /x wide, with extremely long fine filament at opercular pole; opposite filament short, may be hook-like at tip. Vitellaria co-extensive with intestinal limbs except for their anterior portion; vitelline reservoir Y-shaped; both arms may or may not be reunited anteriorly. Vagina unarmed, middorsal, 1.0-1.5 m m fr°m head end. Vaginal duct inverted Y-shaped posteriorly, joining lateral arms of vitelline reservoir. This species differs from any of the known members of the genus in the combined character of the number of clamps and the number of testes. Microcotyle emmelichthyops n. sp. Gills of Emmelichthyops sp.; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No.

FIGURE

184.

137

Microcotylidae

DESCRIPTION

DISCUSSION

179

(Based on 23 whole mounts.) Body lanceolate, 2 . 3 - 1 1 . 0 mm in total length, with maximum width of 0.2-1.2 mm in midregion. Head 0.090.15 mm wide, with more or less flattened apex and paired cell masses, one on each side, immediately in front of oral suckers. Oral suckers oval, septate at middle, 42-70 X 32-82 ¡t. Pharynx globular, 23-58 X 25-47 /*> esophagus 0.25-0.6 mm long, without distinct side branches, though somewhat diverticulate, bifurcating immediately behind genital pore. Intestinal limb with numerous lateral branches, terminating at different levels at posterior end of body proper. Opisthohaptor hatchet-shaped, developed as direct posterior extension of body proper, 0.8-2.5 mm long, with two rows of numerous clamps, the total number of which varies from 62 to 115. Clamps of usual Microcotyle type, 40-80 wide; both prongs of middle spring bifid, that of shorter prong provided with a styliform median piece enclosed in a capsule-like structure at base. Testes rounded, 20-46 in number, occupying whole postovarian interintestinal field in irregular longitudinal rows. Vas deferens only slightly winding in median field, surrounded by gland cells in preovarian area. Muscular bulbus cirri bulbous or conical, 23-70 /x in diameter, unarmed, projecting into genital atrium at its bottom. Genital atrium comparatively large, muscular, constricted into a larger anterior chamber 0.06-0.2 mm in inside diameter and densely lined with rosethorn-shaped spines, and a smaller posterior chamber, at the bottom of which a group of rosethomshaped spines is set on each side of the bulbus cirri. Genital pore oval, large, at center of anterior chamber, 0.27-0.67 mm from head end. On the anterodorsal side of this anterior chamber is attached an oval bulb of lamellar muscle fibers as in Microcotyle polymixiae n. sp. Ovary tubular, turned back on itself twice to form a double loop, measuring 0.25-0.95 X 0.1-0.4 m m a s a whole, with both ends swollen to right of median line. The germiduct arising from the posterior end of the ovary forms an N-shaped curve, its posterior limb serving as seminal receptacle and giving off the genito-intestinal canal before uniting with the vitelline duct. Seminal receptacle cylindrical to claviform, 40-60 /*. wide, lying transversely between the two ends of the ovary. Uterus midventral, containing a longitudinal series of eggs; eggs large, elliptical, with rather pointed ends, 0.18-0.23 X 0.07-0.14 mm; anterior filament very long, fine, usually convoluted terminally; posterior filament much shorter. Vitelline follicles small, co-extensive with intestine and its branches, leaving beginning of intestine and posterior end of longer intestinal limb free; vitelline reservoir Y-shaped, ventral to ovary; stem gently curved, 0.20.5 mm long lineally; two arms apparently emptying into paired longitudinal vitelline ducts, connected with inverted Y-shaped vaginal duct near their outer ends; vaginal pore oval, middorsal, 0.48-1.44 mm from head end, 0.16-0.6 mm posterior to genital pore. This species differs from the most closely related Microcotyle cepolae Yamaguti, 1937 in the genital atrium consisting of a larger anterior and a smaller posterior chamber and in the number of testes (20-46 vs. 15-20). The eggs are shorter than those of M. cepolae.

i8o

138 HABITAT HOLOTYPE DESCRIPTION

DISCUSSION

Microcotyle polymixiae n. sp.

FIGURE 1 3 8

Gills of Polymixia japonica; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 185. (Based on 82 whole mounts.) Body lanceolate, tapered anteriorly, 3 . 5 8.5 mm long, 0.6-1.4 mm wide at level of ovary. Opisthohaptor hatchetshaped in profile, 1.3-1.9 mm long, with 57-88 clamps in two rows, 26-47 on the right and 27-47 on the left. Clamp skeleton 50-90 ¡x in diameter; median spring bifid at both ends; shorter prong with a simple styliform apical appendage, the swollen base of which is enclosed in a capsule-like structure. Head 0.15-0.22 mm in diameter, with rather flattened apex. Oral sucker strongly muscular, septate, unarmed, 39-80 X 46-90 ¡x. Pharynx rounded, 35-51 X 37-60 ¡x; esophagus simple, 0.16-0.4 mm long; intestinal limbs simple anteriorly, but with numerous, short inner, and longer outer branches for most part, terminating separately at posterior end of body proper. Testes oval, very variable in number (15-75), occupying entire postovarian interintestinal field. Vas deferens running straight forward in median field, surrounded by prostate cells for a considerable distance anterior to ovary, though not differentiated into pars prostatica, and by accompanying cells distally. Cirrus projecting in form of a papilla about 25 /x wide, at bottom of posterior recess of genital atrium which is armed laterally with few (3-6) denticles. Genital atrium circular, 60-200X90230 /x, provided with well developed radial muscle fibers, covered inside with sharp-pointed spines 10-12 ¡x long. Immediately anterodorsal to the genital atrium is an oval bulb of lamellar muscle fibers. Genital pore opening ventrally at a distance of 0.2-0.45 mm from head end, a little in front of intestinal bifurcation. Ovary 0.5-1.15 X 0.2-0.45 mm, arising immediately in front of anteriormost testis, ascending on the right of median line and bending back on itself two times, giving rise to germiduct at backwardly directed distal end. Germiduct swollen in form of a seminal receptacle before giving off genito-intestinal canal; latter opening into right cecum behind distal end of ovary. Shell gland complex to left of proximal portion of ovary behind level of origin of genito-intestinal canal. Uterus opening into genital atrium, where it is armed along the inner margin with minute deciduous spines. Two abortive eggs were observed in the uterus of the type, but mature ones observed in paratypes, fusiform, 0.17-0.26 X 0.06-0.095 mm; anterior filament extremely fine, convoluted; posterior filament short, 5060 ix long, usually curved. Vagina simple, unarmed, opening middorsally just in front of body constriction, 0.46-1.3 mm from head end; vaginal duct median, bifurcating before joining arms of vitelline reservoir. Vitellaria co-extensive with intestine except for its simple anterior-most portion; vitelline reservoir Y-shaped, with its stem overlapping ovary; two arms very long, united anteriorly with bifurcate vaginal duct. Of the Microcotyle species hitherto reported, M. pomacanthi MacCallum, 1915 from the Atlantic appears to resemble the present species in the

Microcotylidae

181

number of clamps and testes, but I prefer to regard the Hawaiian species as distinct in view of the fact that the host fish lives in the deep of the Pacific in contrast with the Atlantic host from an unnatural source (New York Aquarium). In this connection, Hargis ( 1 9 5 6 ) suggests that study of material from natural habitats is necessary to define clearly the hosts and the limits of host specificity.

KEY TO SPECIES OF

Microcotyle

FROM HAWAIIAN FISHES

139 HABITAT HOLOTYPE DESCRIPTION

1 Genital atrium scyphiform, without muscle bulb anterodorsally; clamps 4 5 - 6 5 ; testes 1 8 - 4 8 ; parasitic on Bothns: M. bothi Genital atrium otherwise, with spined recess on each side of median line and muscle bulb anterodorsally: 2 2 Clamps 5 7 - 8 8 ; testes 15-75; parasitic on Polymixia: M. polymixiae Clamps 6 2 - 1 1 5 ; testes 2 0 - 4 6 ; parasitic on Emmelichthyops: M. emmelichthyops Aspinatrium kahala n. sp.

FIGURE 1 3 9

Gills of Seriola dumerilii (local name "kahala"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 8 6 . (Based on seven whole mounts.) Body elongate, tapered anteriorly, 8 - 1 6 mm long, widest ( 0 . 6 5 - 1 . 5 mm) in region of testes. Opisthohaptor subsymmetrical, with 6 8 - 7 8 clamps, of which 3 1 - 3 8 are on one side and 3 2 - 4 0 on the other; skeleton of each clamp of Microcotyle type, 4 0 - 1 8 0 /x in transverse diameter; two lateral arms unjointed; longer prong of median spring widely bifid at tip, short prong also widely bifid, but surmounted by dagger-shaped accessory piece, the slender median styliform process of which reaches to the apex of the clamp valve. Head enlarged, 0 . 3 6 - 0 . 6 mm in diameter, with wide oral aperture and prominent dorsal lobe, at the apex of which are paired head organs close together; head gland cells irregular in size and shape are massed together on each side of anterior portion of esophagus. Oral suckers aseptate, 0 . 1 - 0 . 1 1 X 0 . 1 2 - 0 . 1 3 M M > apart one from the other. Pharynx oval, small, poorly muscular, 46-51 FJ. in diameter; esophagus simple, 0 . 1 5 - 0 . 5 mm long, bifurcating a little anterior to genital pore. Intestinal limbs simple anteriorly, branched elsewhere, especially posteriorly, extending into opisthohaptor, where they terminate parallel to each other at different levels. Testes oval, 5 0 - 1 1 0 in number, close together in one layer, occupying entire postovarian interintestinal field. Vas deferens running forward in median field, may or may not be convoluted at or near its distal end. Cirrus rod-shaped in the type, rather rounded conical in the paratypes, unarmed, projecting into genital atrium, provided at its base with a conspicuous bulb (bulbus cirri) of circular and longitudinal muscle fibers, of which the longitudinal extend backward over the distal end of the vas deferens to form bulbus ejaculatorius. Genital atrium 8 0 - 1 6 0 yx transversely in inside diameter, surrounded by well developed lamellar muscles, opening midventrally by a transverse slit at a distance of 0 . 5 5 - 1 . 2 mm from head end.

i8a

DISCUSSION

140 HABITAT HOLOTYPE

Ovary shaped like an interrogation mark, 1 . 3 - 2 mm long by 0.2-0.5 mm wide as a whole, situated largely in posterior half of middle third of body, with its compact proximal end on the right of median line at junction of middle with posterior third of body in the type, the proximal portion ascending in the median line forms an N-shaped curve on the left side of the median line; the distal portion descends on the right of the median line between the stem of the vitelline reservoir and the right intestinal limb; the germiduct arising from the distal end of this descending portion runs backward and gives off the genito-intestinal canal just before joining the vitelline reservoir. Shell gland cells well developed, distributed not only around this genital junction but also in the narrow space among anterior testes. Genito-intestinal canal runs obliquely forward, emptying into right intestinal limb. Proximal uterine duct runs forward along left side of stem of vitelline reservoir. Uterus distended with eggs in the type some distance posterior to vagina, opening into genital atrium ventral to cirrus. Eggs elliptical, 0 . 1 1 - 0 . 1 4 X 0.055-0.07 mm, with very long fine filament at pointed opercular pole. Vitelline follicles commencing shortly posterior to vagina, extending along intestinal limbs and their branches, except for a considerable length of their simple anterior part as well as their simple posterior ends which intrude into opisthohaptor. Vitelline reservoir Y-shaped, extending greater part of middle third of body; its stem comparatively narrow, 1 . 9 - 5 . 8 mm long; arms rather short, 0 . 1 8 - 0 . 4 M M long, uniting with paired vaginal ducts just before the latter join the longitudinal collecting vitelline ducts. Vagina consisting of a transversely elongated oval central body and small paired retort-shaped lateral bodies about 40 ¡x wide at base and lined with cuticular villi, situated at middle of anterior third of body; each of these lateral bodies is connected with the arm of the vitelline reservoir of its own side by a long narrow vaginal duct about 2.8-5.9 m m and running longitudinally just medial to the intestinal limb of the same side; vaginal pore transversely elongated oval, opening middorsally 1 . 2 5 - 2 . 4 mm posterior to head end. This species differs from any of the known members of the genus by the enormous numbers of testes. Aspinatrium pogoniae (MacCallum, 1913) Yamaguti, 1963 from Atlantic Pogonias chromis possesses the most numerous (75) testes among the known Aspinatrium species, but in this species there are 54 clamps on each side and the oral suckers are spined. In all of the other known species [spari (Yam., 1 9 3 7 ) , acanthogobii (Yam., 1 9 4 0 ) , trachini (Par. et Per. 1 8 8 9 ) , and virgatarum (Tubangui, 1 9 3 1 ) ] the testes are under 20 in number. The specific name refers to the local name for the host.

Bivagma kyphosi n. sp. Gills of Kyphosus cinerascens; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No.

FIGURE 140

187.

Microcotylidae

DESCRIPTION

DISCUSSION

183

(Based on six whole mounts.) Body tapered toward both extremities, 2.6-3.4 m m ' n length, with maximum width of 0.29-0.45 mm at level of ovary. Opisthohaptor 0.7-1.0 mm long, subsymmetrical, with subequal number of clamps, of which 30-46 are on the long side and 20-28 on the short side, making a total of 50-62. Clamp skeleton of Microcotyle type; median spring with a styliform apical piece on shorter, terminally bifid prong; longer prong widely bifid at tip. Head end truncate, 0.17-0.26 mm wide, often everted, exposing oral sucker as in the type. Oral sucker oval, 37-50 X 45-80 ¡x. Pharynx 27-38 X 27-35 /X; esophagus very short, with a pair of lateral branches immediately behind pharynx, bifurcating immediately in front of genital pore, with a compact group of cells, probably glandular, on each side. Intestinal limbs with numerous short inner and longer outer branches, but simple at their posterior portion, not accompanied by vitellaria, right one terminating at base of opisthohaptor, but left one reaching to near posterior end of opisthohaptor in the type. Testes comparatively small, 20-30 in number, occupying whole interintestinal field between ovary and posterior end of vitellaria in two longitudinal rows. Vas deferens narrow and undulating. Ejaculatory duct divided into two parts; proximal portion with a thick coat of circular muscles, winding in median field at level of vaginae; distal portion differentiated into a straight cylindrical structure 115-125 /¿ long by 32-43 ¡1 wide and provided with thick wall of very fine circular muscle fibers and a finely annulated cuticular lining. Cirrus projecting into genital atrium in form of an unarmed flattened bulb which is about 50 ¿u. in diameter in the type 3.4 mm long, and crowned with several slender rods. Genital atrium similar in shape to bulbus cirri, 37-40 X 57-70 ¡x, provided inside with a circle of about 30 spines, the tips of which are converged toward the apex of the atrium. Genital pore 0.16-0.22 mm from head end. Ovary tubular, originating at anterior end of testes and, after forming a double loop, gives off the germiduct on the right of median line at about junction of anterior with middle third of body. Genito-intestinal duct opening into right intestinal limb at level of origin of germiduct. Shell gland complex immediately in front of anterior-most testes. Eggs elongated oval, 120-150X60-75 posterior filament terminating in a conical expansion. Vaginae situated symmetrically dorsal to intestine, sucker-like, about 50 ¡x in diameter, opening dorsally, one on each side, just in front of anterior end of vitellaria at level of winding muscular portion of ejaculatory duct; vaginal ducts joining together, but could not be traced further backward. Vitellaria extending along intestine except for its anterior and posterior portions, from level of winding muscular portion of ejaculatory duct to near base of opisthohaptor; vitelline reservoir Y-shaped, with long stem, which curves to the right near its posterior end to join the germiduct. The most outstanding features of this species are the genital atrium being provided with a crown of spines and the ejaculatory duct being differentiated into two portions of entirely different structure.

184

Subfamily

141 HABITAT HOLOTYPE DESCRIPTION

METAMICROCOTYLINAE

Metamicrocotyla

mugilis

Yamaguti, 1963

n . sp.

FIGURE

141

Gills of Mugil cephalus; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 188. (Based on five partly macerated and mutilated whole mounts.) Body elongate, 7-10 mm long, widest (0.6-0.8 mm) near anterior extremity or a little more posteriorly. Prehaptoral region somewhat enlarged and frilled laterally, where the ventral median interintestinal field projects in form of a laterally well delimited knob 0.2 mm in diameter in the type. Opisthohaptor elliptical, flat, well constricted off from body proper, 1 . 1 1.2 X 0.4-0.6 mm, with symmetrical longitudinal rows of 19 clamps each; clamp skeleton of Microcotyle type, 6 0 - 1 3 0 ¡x wide, gradually diminishing in size posteriorly, consisting of two pairs of slender unjointed lateral arms, a median spring with an apical spine on shorter prong, and a pair of short basal pieces. Oral suckers aseptate, 46-58 X 35—46 ¡x, fringed with minute spines along anterior margin. Pharynx 37-46 X 37-46 esophagus narrow, 0.3-0.8 mm long, not diverticulate, bifurcating dorsal to genital atrium. Intestinal limbs with numerous side branches, terminating at different levels in opisthohaptor; in the type the right limb reaches to near the posterior end of the opisthohaptor, whereas the left limb ends near the anterior end of the haptor. Testes rounded or oval, smaller posteriorly, 76-86 in number, arranged in a double or zigzag row in median field, extending from behind ovary to junction of middle with posterior third of body and not reaching to posterior end of vitellaria. Vas deferens distended with sperm, strongly winding in median field between ovary and genital atrium. Neither cirrus nor cirrus pouch. Genital atrium only 46 ¡x in transverse inside diameter in the type, armed with three pairs of bundles of inwardly directed, terminally recurved, acicular spines; each bundle consists of 5 or 6 spines, the total number of the spines varying from 15 to 18, and their length varying from 45 ¡x to 70 ¡x, the anterior-most spines being the shortest and the middle ones the longest. Genital pore at intestinal bifurcation, 0.40.9 mm from head end. Ovary shaped like an interrogation mark, measuring 0.6-0.7 X O-2S~°-42 mm as a whole, with its nodular proximal end immediately in front of anterior-most testes and its distal end on right side of stem of vitelline reservoir. Germiduct twisted, giving off genito-intestinal canal just before joining stem of vitelline reservoir immediately anteroventral to proximal swelling of ovary. Uterus midventral, straight, muscular for greater distal portion, opening into genital atrium. Eggs not observed. Vitellaria coextensive with intestinal limbs, except their beginning and posterior portion extending into opisthohaptor. Vitelline reservoir Y-shaped, ventral to ovary; its stem sigmoid, 0.25-0.35 mm long lineally. Vagina absent.

Microcotylidae

185

DISCUSSION

This species differs from the most closely related Metamicrocotyla bora Yamaguti, 1953, from Mugil cephalus of Macassar, in the number of clamps and testes and in the posterior extent of the vitellaria. The ventral median prehaptoral lcnob is one of the important features differentiating the present species from all other known members of the genus.

Subfamily

PROSTATOMICROCOTYLINAE

142 HABITAT HOLOTYPE DESCRIPTION

n. subf.

Prostatomicrocotyla kuhliae n. g., n. sp.

FIGURE 1 4 2

Gills of Kuhlia sandvicensis; Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 189. (Based on five whole mounts.) Body elongate, tapering toward both extremities, 2.2-3.3 x o-3-°-55 m m - Opisthohaptor extending obliquely, beginning at level of posterior testes, with 80-120 clamps in two subequal rows; clamp skeleton 20-45 /* wide, consisting of two pairs of unjointed arcuate lateral sclerites, a pair of short incurved basal sclerites, and a median spring with bifid ends; to the apex of the shorter prong of the median spring is attached a styliform piece; accessory sclerites absent. Head 0.12-0.14 mm wide; in the type it is approximately 3-lobed, each lobe bearing a few head organs. Oral sucker 37-63 X 45-63 /t, unarmed, but septate at middle. Pharynx bulbous, 35-50 X 30-33 ¡i; esophagus 0.120.28 mm long, with a pair of lateral diverticles toward its middle. Intestinal limbs with inner and outer branches; left limb extending a little beyond right one and terminating about midlevel of opisthohaptor. Testes round, comparatively large, 7-19 in number, occupying nearly whole postovarian interintestinal field in middle third of body. Vas deferens may be strongly distended with sperm and convoluted; ejaculatory duct sigmoid, provided with well developed, circular muscles; its distal end passes through a bulb of circular muscle fibers and terminates in a narrow, sclerotized, cylindrical cirrus enlarged a little at tip. This cirrus is 4250 p. long, guarded by a conical sclerotized sheath, through the apex of which it projects into the genital atrium. Genital atrium oval to elliptical, unarmed, 65-70 X 30-63 ¡x, with its wall provided with lamellar muscle fibers, enclosing above mentioned muscle bulb (bulbus cirri), cirrus, and conical sheath of cirrus. In the type the cirrus appears to consist of a conical distal half and a cylindrical proximal half, but in one of the paratypes it appears undivided. Genital pore ventral to posterior part of esophagus at a distance of 0.16-0.26 mm from head end. In this species as well as in the related species from Abudufdef abdominalis symmetrical prostatic complexes characteristic of the genus are present. Each half consists of a small prostatic vesicle containing fine granules and surrounded by prostate cells and a cylindrical prostatic duct, the proximal end of which is constricted by a sphincter and the distal end of which joins the

i86

DISCUSSION

143 HABITAT HOLOTYPE DESCRIPTION

corresponding part of the opposite duct and opens into the base of the cirrus midventrally. Ovary inverted U-shaped, 0.4 mm long longitudinally, situated in the type at junction of anterior with middle third of body, with both ends directed backward. Genito-intestinal duct short, opening into right intestinal limb near distal end of ovary. After joining the vitelline reservoir the germiduct runs obliquely backward to be enclosed in the shell gland complex. Uterine eggs one at a time, elongate oval, 0 . 1 4 - 0 . 1 6 X 0 . 0 7 5 - 0 . 1 mm, with a fine filament at each pole. Vitellaria co-extensive with intestine. Vagina with thick sclerotized margin, opening midventrally a short distance behind intestinal bifurcation, 0 . 3 3 - 0 . 5 7 mm from head end; vaginal ducts symmetrical, outcurved near vagina, then parallel to each other and distended with sperm, each opening into arm of vitelline reservoir of its own side near its outer end. This species is characterized by the midventral vaginal aperture and the symmetrical prostatic complexes, the efferent ducts of which open jointly into the base of the cirrus. Such a prostatic complex has never been observed in any of the known microcotylid Monogenea. This feature alone constitutes not only a generic but also a subfamily character. The new compound generic name refers to this feature.

Prostatomicrocotyla maomao n. sp.

FIGURE 1 4 3

Gills of Abudefduf dbdominalis (local name "maomao"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 1 9 0 . (Based on 1 9 whole mounts.) Body lanceolate, 2 . 6 - 3 . 6 mm long, 0 . 2 5 0.5 mm wide in midregion or at anterior part of cotylophore. Opisthohaptor 1.0-1.7 m m l°ng> commencing at equatorial level and projecting far back of body proper, with 9 5 - 1 2 5 clamps of Microcotyle pattern; 5 8 clamps on the right and 57 on the left in the type; lateral arms of clamp slender, unjointed; median spring bifid at both ends, its shorter prong with a styliform apical piece. Head with flattened conical apex, 0.1 mm wide; a median apical and paired submedian head organs present. Mouth wide, ventrosubterminal; oral sucker septate, 50 X 60 Pharynx pyriform, 304 6 X 2 3 - 3 7 /*; esophagus simple, 0 . 0 9 - 0 . 1 9 mm long, bifurcating immediately behind genital pore; intestinal limbs with short branches, terminating close to each other at different levels about middle of opisthohaptor. Testes rounded, 15-25 in number, occupying whole anterior postovarian interintestinal field. Vas deferens undulating in pre-ovarian median field; ejaculatory duct sigmoid, provided with circular muscles. Cirrus tubular, consisting of a proximal portion guarded by conical sclerotized sheath (30 ju long by 26 /x wide in the type) and a well sclerotized, spiniform, distal portion, the tapering tip of which is recurved and projects out of the genital pore. Prostatic complex as in the type species of the genus.

Microcotylidae

DISCUSSION

Genital atrium not well developed, unarmed, opening ventral to posterior part of esophagus. Ovary tubular, looped twice, 0.3-0.53 X 0.07-0.25 mm, originating immediately in front of anterior-most testes. In the type it ascends medial to the right intestinal limb, and after crossing anterior part of stem of vitelline reservoir dorsally turns backward, then forward, and after forming another loop gives off the germiduct at its distal end. Uterus midventral, differentiated into metraterm before opening into genital atrium. No mature eggs observed, though a longitudinal series of round to oval immature eggs was seen in one paratype. Vagina unarmed, opening midventrally shortly behind intestinal bifurcation; vaginal ducts outcurved near vagina, then parallel to each other, each opening into arm of vitelline reservoir of its own side. Vitellaria co-extensive with intestine; vitelline reservoir Y-shaped, overlapping ovary. This species differs from the closely related Prostatomicrocotyla kuhliae n. sp. in the absence of lamellar muscles at the base of the cirrus and around the genital atrium. PROSTATOMICROCOTYLINAE

SUBFAMILY DIAGNOSIS

187

n. subf.

Microcotylidae. Opisthohaptor similar to that of Microcotylinae, not divided into two separate marginal frills. Vitellaria extending whole length of intestine. Symmetrical prostatic complex connected with cirrus. Vagina opening midventrally, vaginal ducts inverted U-shaped. Prostatomicrocotyla n. g.

GENERIC DIAGNOSIS

T Y P E SPECIES OTHER SPECIES

Microcotylidae, Prostatomicrocotylinae. Body elongate. Opisthohaptor symmetrical or subsymmetrical, projecting backward beyond body proper, with numerous clamps of Microcotyle pattern, commencing at level of posterior testes. Anchor-bearing terminal lobe absent. A median and paired submedian head organs present. Prohaptoral suckers septate; pharynx bulbous; esophagus bifurcating posterior to genital pore; intestinal limbs with side branches, not united posteriorly. Testes postovarian; ejaculatory duct sigmoid, muscular. Symmetrical prostatic ducts opening together into cirrus; cirrus tubular, with sclerotized sheath. Genital atrium unarmed; genital pore prebifurcal. Ovary tubular, looped. Genito-intestinal duct present. Eggs filamented at both poles. Vagina opening midventrally; vaginal ducts symmetrical, each opening into arm of Y-shaped vitelline reservoir. Vitellaria extending whole length of intestine. Gill parasites of marine teleosts. P. kuhliae n. sp. P. acanthogobii (Yamaguti, 1940) n. comb., syn. Microcotyle acanthogobii Yamaguti, 1940; P. maomao n. sp.; P. spari (Yamaguti, 1937) n. comb., syn. Microcotyle spari Yamaguti, 1937.

i88

Family

144 HABITAT HOLOTYPE DESCRIPTION

ALLOMICROCOTYLIDAE Yamaguti, 1965

Allomicrocotyla

onaga Yamaguti, 1965

FIGURE

144

Gill of Etelis carbunculus (local name "onaga"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 18. (Based on five whole mounts.) Body proper fusiform to elliptical, 2.54.0 X 0.8-1.6 mm. Opisthohaptor shaped like an asymmetrical fan fringed with two rows of clamps along its semicircular posterior margin which is 0.8-1.4 mm long. At one end of the opisthohaptor there are two pairs of anchors of different size and shape. Clamps 40-63 in number, arranged in two rows of equal or subequal length, 20-31 in one row and 20-33 in the other; clamp skeleton of uniform structure, consisting of a basally jointed median spring, two pairs of unjointed lateral arms, and a pair of basal sclerites, each of which articulates with the base of the two lateral arms at one end and with the enlarged end of dorsal prong of the median spring at the other end; the narrow solid ventral prong tapers toward its bifid tip reaching the tips of the ventral lateral arms, while the short dorsal prong curves ventrad and terminates in a transversely enlarged solid pad which is united by muscle with another ventrally curved hollow median sclerite reaching to tip of dorsal lateral arms. Head more or less pointed anteriorly, 0.11-0.13 mm wide at level of oral suckers; at the apex is a compact group of gland ducts originating from the group of parapharyngeal, postsuctorial gland cells and passing dorsal to the oral suckers. I prefer to designate the apical group of gland ducts as apical organ, and the parapharyngeal mass of gland cells as apical gland or head gland although the structural details of the gland cells could not be discerned except for the granular cytoplasm surrounding the dark-staining nucleus which is definitely larger than the adjoining parenchymatous nuclei. Mouth comparatively wide, opening ventrally at level of base of head. Oral suckers opening into buccal cavity, one on each side of anterior end of pharynx, strongly muscular, aseptate, 40-55 ¡x X 50-56 ¡x. Pharynx pyriform, 37-65 X 32-51 ¡x, cellular except at the apex which is provided with circular muscle fibers. Nerve commissure and paired nerve trunk conspicuous, former dorsal to anterior end of esophagus. Esophagus simple, without diverticles; intestinal limbs simple at the beginning as well as at the posterior portion intruding into the opisthohaptor, giving off numerous short inner and longer outer branches in swollen region of body proper. Testes rounded, 10-20 in number, arranged irregularly in postovarian interintestinal fieM, but not beyond level of posterior end of vitellaria. Vas deferens slightly winding on the right of median line, provided with a dense coat of prostatic cells along greater distal portion. No pars prostatica differentiated. Ejaculatory duct wider than distal end of vas deferens, provided with circular muscle fibers. Cirrus complex, consisting of

Allomicrocotylidae

189

a more or less pointed pyriform bulbus cirri of lamellar muscles enclosed in a horseshoe-shaped pad of lamellar muscles, and an inverted cone, on the anterior base of . which is set a midventrally interrupted crown of long, apically outcurved spines projecting into the genital atrium. The pointed conical apex of the bulbus cirri fits into the midventral groove of the above-mentioned cone and projects a little into the base of the genital atrium, whereas the apex of the inverted cone is attached to the middorsal side of the bulbus cirri. The ejaculatory duct leads into the bulbus cirri ventral to this point of attachment. Genital atrium forming a powerful ring (69-84 in outside diameter) of circular muscle fibers basally, but thin-walled distally, provided with circular and longitudinal muscles; the latter fibers extend backward over the atrial ring and continue to the outer surface of the horseshoe-shaped muscle pad, thus simulating the cirrus pouch. Common genital pore ventral to posterior part of esophagus, 0.28-0.35 mm from head end.

DISCUSSION

Ovary shaped like an interrogation mark, 0.5-0.7 X 0.35-0.4 mm, originating at posterior end of middle third of body to right of median line; its swollen distal portion with three constrictions in the type and occupying whole breadth of interintestinal field. Genito-intestinal duct crossing proximal portion of ovary and emptying into right intestinal limb. Uterus midventral, very wide, may be distended with numerous eggs, thus occupying greater part of pre-ovarian interintestinal field, opening into genital atrium across rim of atrial ring mentioned above. Uterine eggs elongate oval, 1 3 0 - 1 5 2 x 6 5 - 7 2 n; anterior filament rather rigid, 35-70 ¡i long; posterior filament extremely long and slender, forming close coils at posterior end of egg. Vagina funnel-shaped, 58 /n by 30 ¡i in the type, provided with circular and longitudinal muscle fibers, opening dorsally just on the right of median line shortly behind intestinal bifurcation; vaginal duct arising from posterior end of vagina, provided with heavily sclerotized walls down to end of its fusiform swelling, then reduced to a narrow duct, but soon becoming enlarged to a small ampulla 23-39 ¡t. long by 18-26 fi wide. The comparatively wide duct arising from the posterior end of this ampulla soon (70 p. behind the ampulla in the type) divides into inverted V-shaped duct distended with yolk cells. Each limb of this duct empties into the lateral arm of the Y-shaped vitelline reservoir of its own side, so that the vagina is directly connected with the vitelline reservoir. Vitellaria co-extensive with intestine and its branches in fusiformly enlarged portion of body proper, leaving simple anterior and posterior portions of intestine free. Vitelline reservoir Y-shaped, largely overlapping ovary. This genus bears a certain resemblance to Pyragraphorus Sproston, 1946 and Mlopyragraphorus Yamaguti, 1963 in general anatomy, but it differs fundamentally from both of them in the structure of the clamp skeleton, especially in the paired basal pieces articulating with the median piece. Moreover, the structure of the cirrus is entirely different from that of any of the known members of the Monogenea. In view of these characteristics

îço

there is no doubt that this genus represents a distinct family. For the diagnosis of the family and further details, see Pacific Science 19(1): 91-94.

Superfamily Family Subfamily

145 HABITAT HOLOTYPE DESCRIPTION

POLYSTOMATOIDEA Price, 1936 HEXABOTHRIIDAE Price, 1942 HEXABOTHRIINAE

Price,

1942

Hexabothrium dasyatis n. sp.

FIGURE 1 4 5

Gills of Dasyatis sp. (D. hawaiiensis ?); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 191. (Based on 51 whole mounts, of which 30 were fixed in Schaudinn's solution and 2 1 in formalin.) Body slender, 4 - 1 0 . 5 mm in length, with maximum width of 0 . 4 - 0 . 9 mm at middle of anterior half of body; posterior half gradually attenuated posteriorly, but enlarged laterally at level of middle pair of suckers of opisthohaptor. The suckers and sclerites of the opisthohaptor gave the following measurements (length of sclerite was measured lineally from the height of anterior curve to that of posterior curve): Anterior sucker 0 . 1 - 0 . 1 4 X 0 . 0 7 - 0 . 1 2 mm; anterior sclerite 0 . 1 4 - 0 . 1 9 mm long. Middle sucker 0 . 1 - 0 . 1 7 X 0 . 0 8 - 0 . 1 4 m m > middle sclerite 0 . 1 6 - 0 . 2 1 mm long. Posterior sucker 0 . 2 - 0 . 3 mm in diameter; posterior sclerite 0 . 2 8 - 0 . 3 4 m m Each posterior sucker is surmounted by a conspicuous lamellar muscle bolster, to which is attached a strong bundle of muscle fibers coming from the posterior wall of the body proper; a weaker muscle bundle is attached to each of the other suckers, though there is no special muscle bolster as seen for the posterior sucker. Haptoral appendix arising dorsally between two anterior suckers, cylindrical, 0 . 3 - 0 . 7 mm long, 0 . 1 5 - 0 . 3 4 mm wide at distal end provided with a pair of anchors 4 0 - 5 0 ju. long and a pair of protrusible suckers; this sucker usually 0.12-0.16 mm long by 0.08-0.1 mm wide, but wider than long (0.08-0.1 X 0 . 1 3 - 0 . 1 4 mm) when protruded. Oral sucker ventroterminal, 0 . 1 5 - 0 . 2 6 X 0 . 2 5 - 0 . 4 mm, surmounted by a preoral lobe 4 0 - 9 0 jx anteroposteriorly, distinctly notched at its bottom. Prepharynx 5 0 - 1 2 0 ¡x long; pharynx globular, 4 5 - 7 0 X 4 2 - 7 0 /*; esophagus 0 . 1 - 0 . 3 3 m m l°ng> with lateral branches posteriorly. Intestinal limbs with numerous diverticles at greater anterior portion, united in center of opisthohaptor, sending a pair of lateral diverticles and a posterior into space between suckers, and a dorsal into haptoral appendix. Testes very irregular in outline, 15-38 in number, arranged irregularly in postovarian interintestinal field. Vas deferens strongly distended (up to 0.16 mm) with sperm and winding forward in median field from in

Hexabothriidae

DISCUSSION

146 HABITAT DESCRIPTION

191

front of testicular area. There is a large elliptical cirrus pouch 0 . 5 - 0 . 8 5 mm long by 0 . 1 - 0 . 3 5 m m and occupying almost entire postbifurcal interintestinal field; at its posterior end is a prostatic vesicle about 6 0 - 1 2 0 P in diameter; prostatic cells profusely developed around posterior end of cirrus pouch. The distal portion of the ejaculatory duct is differentiated into a wide, densely spined cirrus which is 0 . 3 5 - 0 . 7 mm long. Genital pore ventromedian, just behind intestinal bifurcation. Ovary tubular, winding, 0 . 1 - 0 . 3 m m l°ng> situated to right of median line immediately in front of testes; the germiduct arising ventrally from the anterior end of the ovary joins the duct from the retort-shaped seminal receptacle 50-90 ¡x in diameter at the point where it gives off the genitointestinal canal, and then unites with the vitelline reservoir. Uterus ventral to male terminal duct, opening ventrally by common genital pore. Eggs elliptical, 1 5 0 - 1 8 0 X 6 0 ¡j. in life, produced at each pole into filament variable in length ( 1 0 0 - 1 5 0 /*). Vitellaria co-extensive with greater anterior part of intestinal diverticula, but very few at posterior cecal union and its posterior extension; vitelline reservoir Y-shaped, immediately preovarian; each arm joining vaginal duct near its lateral end. Vaginal apertures wide, symmetrical, one on each side of anterior end of cirrus pouch; vaginal ducts running parallel to each other along intestinal limbs, each forming fusiform or cylindrical muscular swelling 0 . 2 - 0 . 3 mm long before uniting with arm of vitelline reservoir. This species resembles Hexabothrium appendiculatum (Kuhn, 1 8 2 9 ) and H. canicula (Cerf., 1899) but is much more slender than either of them.

Erpocotyle sphyrnae (MacCallum,

1931)

Price,

1942

FIGURE 1 4 6

Gills of Sphyrna lewini; Hawaii. (Based on 1 0 whole mounts.) Body tapered anteriorly, 2 . 1 - 6 . 0 mm in length exclusive of caudal appendix, 0.3-0.8 mm wide in testicular region. Opisthohaptor 0 . 5 6 - 1 . 2 8 mm wide at level of middle pair of haptoral suckers; suckers 0.08-0.2 mm in diameter; haptoral hook with sharppointed claw, 0 . 3 5 - 0 . 5 mm long along its curve; caudal appendix 0.3-0.6 X 0 . 1 6 - 0 . 4 5 mm, with a pair of terminal suckers 0 . 1 - 0 . 1 6 mm in diameter and a pair of hooks 25-60 ¡¡. long between two suckers, each of which is provided at the base with a small sucker-like diverticle 25 x 37 p. Head bowl-shaped, 0 . 1 2 - 0 . 3 6 mm wide. Mouth with six (two median and four submedian) muscular pits of irregular outline at bottom. Pharynx 3 5 - 5 0 X 3 0 - 7 0 /A; esophagus 0.04-0.25 mm long; intestinal limbs united posteriorly and then prolonged posteriorly, giving off a blind extension into caudal appendix, where it terminates near the paired hooks. Testes round to oval, 3 0 - 6 0 in number, occupying whole postovarian interintestinal field. Vas deferens strongly winding; ejaculatory duct cylindrical, 0 . 1 4 - 0 . 1 8 mm long, with well developed longitudinal muscles;

192

DISCUSSION

cirrus enclosed in an elongate oval or elliptical muscular sac 0.13-0.25 mm long by 0.04-0.08 mm wide; cirrus unarmed. Genital pore ventromedian, shortly postbifurcal, 0.26-0.6 mm from head end. Ovary 0.22-0.6 X 0.18-0.3 mm, irregular in outline, largely to left of median line, originating just in front of anterior-most testes, turning back on itself before giving rise to germiduct; seminal receptacle 25-75 x 10-54 /»> immediately in front of distal end of ovary. Genito-intestinal duct crossing ovary on its ventral side and opening into left intestinal limb. Shell gland complex anterior to seminal receptacle. Uterus midventral; eggs fusiform, 132-180 X 37-58 jx in life, with filament 0.1-0.12 mm long at each pole. Vagina elongate, 0.16 mm long, ciliated inside, opening ventrosublaterally, just behind level of genital pore; vaginal ducts parallel to each other, apparently opening into arms of vitelline reservoir. Vitellaria co-extensive with intestine and its posterior extensions. As compared with Price's description of MacCallum's original slides, our Hawaiian specimens show different measurements, especially in the pharynx ( 1 1 4 X 95 ¡x after Price). Price did not mention the six muscular pits at the bottom of the mouth, one of the characteristics of this species, nor the presence of a diverticle-like accessory sucker at the inner end of each sucker of the haptoral appendix. In Price's figure 1 B (1942) the esophagus is practically lacking, but in our specimens it is distinct, measuring 0.04-0.25 mm in length.

Appendix Order

ASPIDOCOTYLEA Monticelli, 1892

Family

ASPIDOGASTERIDAE Poche, 1907

Subfamily

147 HABITAT HOLOTYPE DESCRIPTION

ASPIDOGASTERINAE

Lobatostoma

albulae n. sp.

FIGURE

147

Intestine of Albula vulpes (local name "o'io"); Hawaii. U.S. Nat. Mus. Helm. Coll., S.Y. No. 192. (Based on two whole mounts.) Body massive, 2.3-2.9 mm long, covered ventrally by large elliptical haptoral shield which is 1.4-2.0 mm long by 0.8-1.3 mm wide. This ventral shield is divided anterior to uterus into a number of small alternating alveoli and laterally into a longitudinal row of 13 large alveoli with marginal sense organs; the greater part of the ventral surface is provided with two longitudinal rows of transversely elongated alveoli; the length of the body posterior to the haptoral shield is about 0.5 mm. Head end with three anterior lobes and two large posterior lobes, with mouth aperture in center. Prepharynx 50-120 ¡a long; pharynx strongly muscular, 0.13-0.15X0.1-0.15 mm; esophagus leading into intestine at level of anterior end of ventral shield; cecum could not be traced to its posterior end. Testis ovoid, 0.4-0.5 X 0.32-0.35 mm, just postequatorial, sinistral. Cirrus pouch oval, 0.1-0.16 X 0.09-0.12 mm; genital pore to left of median line at level of anterior end of haptoral shield. Ovary oval, 0.16-0.2 X 0.14-0.16 mm, immediately pretesticular. Vitellaria in two lateral longitudinal rows extending from near anterior end of haptoral shield to level of its posterior end; vitelline reservoir compact (90 wide in the type), situated laterally between ovary and testis. Uterine coils extending from left side of ovary and testis to posterior extremity and occupying whole intervitellarian field. Eggs elliptical, embryonated, 80-93

DISCUSSION

Chauhan, 1954

X

55-63 /T.

The present species, the second species of the genus from the Pacific, appears more closely related to Lobatostoma ringens (Linton, 1907) Eckmann, 1932 than to any other species, but differs from it in the number of the marginal loculi (36-42 in L. ringens), in the proportion of the body posterior to the haptoral shield being distinctly shorter, and in the testis being almost contiguous to the ovary.

41 Host-parasite list

The hosts are arranged in alphabetical order for convenience of reference (after Handbook of Hawaiian Fishes by Gosline and Brock, i960), regardless of their systematic relationships. T h e names of the parasites listed here are all new except for those in which the original authors' names and dates are given. The number of hosts examined is indicated in parentheses after each host name. The hosts which were examined and in which no Monogenea were found, as well as those from which Monogenea were recovered but no mounts were available for identification, are not listed.

PARASITE

HOST

Ablennes hians (28) Abudefduf

abdominalis (45)

Acanthocybium solandri (7) Acanthurus dussumieri ( 1 7 )

Acanthurus leucopareius (5) Acanthurus mata (10)

Acanthurus nigrofuscus (20)

Acanthurus nigroris (25)

Acanthurus olivaceus (25) Acanthurus sandvicensis (50) Acanthurus thompsoni (15) Aethobatis narinari (2) Albulavulpes (16) Alutera scripta (10) Amanses carolae (8) Amanses pardalis (20) Amanses sandwichiensis (5) Aphareus rutilans (2)

Axinoides diploporus Axinoides kola Unnithan, 1957 Benedenia hawaiiensis Neohaliotrema maomao Yamaguti, 1965 Prostatomicrocotyla maomao Capsala nozawae (Goto, 1894) Neothoracocotyle acanthocybii (Meserve, 1938) Benedenia hawaiiensis Cleithrarticus cleithrarticus Mizelle, 1963 Cleithrarticus bulbovagina Haliotrema palmatum Haliotrema serpenticirrus Haliotrema sigmoidocirrus Haliotrema zancli Haliotrema flexicirrus Cleithrarticus cleithrarticus Mizelle, 1963 Haliotrema palmatum Haliotrema sigmoidocirrus Haliotrema zancli Benedenia hawaiiensis Haliotrema ctenochaeti Haliotrema flexicirrus Haliotrema angulare Haliotrema flexicirrus Haliotrema macracantha Cleithrarticus cleithrarticus Mizelle, 1963 Haliotrema zancli Haliotrema acanthuri Haliotrema macracantha Alloheterocotyla aetobatis (Hargis, 1955) Pseudopterinotrema albulae Yamaguti, 1966 Lobatostoma albulae Benedenia hawaiiensis Benedenia hawaiiensis Enoplocotyle hawaiiensis Haliotrema amanses Benedenia hawaiiensis Pseudattobenedenia apharei Yamaguti, 1966 Diplectanum opakapaka

Host-parasite list

Aprion virescens ( 8 ) Artiillo auricilla (18) Arothron hispidus (25) Auxis thazard (15) Balistes bursa (10) Belone platyura (3) Bodianus bilunulatus (25) Bothus maneus (10) Brotula multibarbata (6) Caesioperca thompsoni (4) Caprodon schlegelii (4) Carangoides sp. ( 1 ) Caranx helvolus (2) Caranx lugubris (3) Caranx mate (38) Caranx sexfasciatus (8) Centropyge potteri (6)

Chaetodon auriga (20)

Chaetodon corallicola (3) Chaetodon fremblii (40) Chaetodon lunula

(15)

Chaetodon miliaris (122)

Chaetodon multicinctus (7) Chaetodon ornatissimus (1) Chromis ovalis (37)

Chromis verater (22) Coris flavovittatus ( 3 ) Coris gaimardi ( 1 ) Ctenochaetus strigosus (25) Cypselurus spilonotopterus

Dactylopterus orientalis (6) Dascyllus albisella (30) Dasyatis sp. (4) Decapterus maruadsi (11) Decapterus pinnulatus (45)

(17)

195

Pseudodiscocotyla opakapaka Yamaguti, 1965 Pseudonitzschia uku Yamaguti, 1965 Pseudobetiedenia elongata Diplectanum curvivagina Ancyrocephalus ornatus Hexostoma keokeo Enoplocotyle hawaiiensis Axinoides bulbosus Benedenia bodiani Haliotrema bodiani Microcotyle bothi Haliotrema brotulae Haliotrema spiculare Haliotrema caesiopercae Enoplocotyle hawaiiensis Heteraxinoides caprodontis Allomonaxine carangoides Yamaguti, 1965 Cemocotylella carangis Pseudempleurosoma carangis Yamaguti, 1965 Neomicrocotyle carangis Pseudaxine decapteri Protomicrocotyle celebesensis Yamaguti, 1953 Pseudempleurosoma carangis Yamaguti, 1 9 6 ; Enoplocotyle hawaiiensis Haliotrema pterophdlus Haliotrema centropygis Haliotrema annulocirrus Pseudohaliotrematoides aurigae Pseudohaliotrematoides microphallus Pseudohaliotrematoides triangulovagina Haliotrema jlagellatum Haliotrema -flagellatum Haliotrema spirale Enoplocotyle hawaiiensis Haliotrema annulocirrus Pseudohaliotrematodes aurigae Benedenia hawaiiensis Haliotrema microphallus Haliotrema scyphovagina Haliotrema scyphovagina Haliotrema microphallus Benedenia hawaiiensis Haliotrema chromidis Haliotrema pterophallus Haliotrema brotulae Haliotrema pterophallus Benedenia lolo Benedenia lolo Haliotrema ctenochaeti Haliotrema zancli Axine spilonotopteri Cypselurobranchitrema spilonotopteri Yamaguti, 1966 Parancyrocephaloides dactylopteri Benedenia hawaiiensis Diploheterocotyla dasyatis Yamaguti, 1965 Hexabothrium dasyatis Pseudaxine decapteri Pseudodichlidophora decapteri Yamaguti, 1965 AUopseudodichlidophora opelu Yamaguti, 1965

196

Dendrochirus brachypterus (8) Emmelichthyops sp. (8) Epinephelns quernus (8)

Etelis carbunculus (6)

Etelis marshi (29) Euthynnus yaito (57)

Forcipiger longirostris (30) Hemiramphus depauperatus (36) Holocentrus lacteoguttatus (42) Holocentrns sammara (8) Holocentrus scythrops (2)

Holocentrus spinifer (4) Istiompax marlina ( 1 ) Istiophorus orientalis ( 1 ) Katsuwonus pelamys (58) Kuhlia sandvicertsis (35)

Kyphosus cinerascens (18)

Lactoria diaphanus (12) Lepidocybium flavobrunneum (11)

Makaira ampia (1) Makaira audax (7)

Makaira sp. (2) Melichthys vidua (10) Merinthe macrocephala (12) Monotaxis grandoculis (?) (4) Mugil cephalus Mulloidichthys Mulloidichthys Mulloidichthys

(23) auriflamma (22) pfluegeri (54) samoensis (27)

Myripristis berndti (46) Myripristis chryseres (10) Naso annulatus (1) Naso brevirostris (25)

Pseudaxine decapteri Enoplocotyle hawaiiensis Microcotyle emmelichthyops Allobenedenia epinepheli Haliotrema epinepheli Diplectanum quemi Pseudobenedenia ovalis Lagenivaginopseudobenedenia etelis Yamaguti, 1966 Allomicrocotyla onaga Yamaguti, 1965 Pseudobenedenia ovalis Neohexostoma kawakawa Mlopseudaxine yaito Allopseudaxinoides euthynni Yamaguti, 1965 Pseudohaliotrematoides triangulovagina Axine depauperati Haliotrema chelicirrus Haliotrema chelicirrus Benedenia hawaiiensis Enoplocotyle hawaiiensis Haliotrema chelicirrus Benedenia hawaiiensis Pseudohaliotrematoides falcatus Capsala ovalis (Goto, 1894) Capsala ovalis (Goto, 1894) Capsaloides istiophori Allopseudaxine katsuwonis (Ishii, 1936) Mlopseudaxine vagans (Ishii, 1936) Murraytrematoides kuhliae Diplectanum kuhliae Prostatomicrocotyla kuhliae Diplectanum diplobulbus Diplectanum nenue Diplectanum spiculare Acleotrema kyphosi B ¡vagina kyphosi Haliotrema lactoriae Pseudopisthogyne lepidocybii Yamaguti, 1965 Allopseudopisthogyne constricta Yamaguti, 1965 Pseudopisthogynopsis lepidocybii Yamaguti, 1965 Capsala ovalis (Goto, 1894) Capsaloides sinuatus (Goto, 1894) Capsala ovalis (Goto, 1894) Capsaloides istiophori Capsaloides sinuatus (Goto, 1894) Capsaloides cristatus Capsaloides nairagi Haliotrema brotulae Pseudobenedenia merinthe Lamellodiscus epsilon Haliotrema angulocimis Metamicrocoyla mugilis Haliotrema spirale Haliotrema spirale Benedenia hawaiiensis Haliotrema spirale Pseudempleurosoma carangis Yamaguti, 1965 Ancyrocephalus pauu Nasobranchitrema pacificum Yamaguti, 1965 Pseudancyrocephalus kala

Host-parasite list

Naso hexacanthus

(36)

Naso lituratus (15) Naso unicornis (17)

Neothunnus

macropterus ( 3 1 )

Ostichthys japonicus (4) Parathunnus sibi (26)

Pseudancyrocephalus longicirrus Pseudancyrocephalus longispicularis Pseudoancyrocephalus nasonis Nasobranchitrema pacificum Yamaguti, 1965 Benedenia hawaiiensis Nasobranchitrema pacificum Yamaguti, 1965 Oligoncobenedenia nasonis Yamaguti, 1965 Pseudancyrocephalus kala Pseudancyrocephalus longicirrus Nasobranchitrema pacificum Yamaguti, 1965 Pseudancyrocephalus duplicatus Dioncopseudobenedenia kala Yamaguti, 1965 Dioncopseudobenedenia macracantha Capsala gotoi Capsala neothunni Capsala (Cabdlerocotyla) biparasitica 1894) Areotestis sibi Yamaguti, 1965 Nasicola klawei (Stunkard, 1962) Hexastoma sibi Neohexostoma kawakawa Sibitrema poonui Ancyrocephalus pauu Capsala gotoi

Priacanthus cruentatus (25)

Capsala nozawae (Goto, 1894) Capsala (Cabdlerocotyla) biparasitica 1894) Nasicola klawei (Stunkard, 1962) Hexostoma sibi Sibitrema poonui Yamaguti, 1966 Areotestis sibi Yamaguti, 1965 Axine belones Abildgaard, 1794 Benedenia hawaiiensis Ancyrocephalus parupenei Haliotrema spirale Haliotrema minutospirale Benedenia hawaiiensis Ancyrocephalus parupenei Haliotrema minutospirale Benedenia hawaiiensis Haliotrema minutospirale Haliotrema spirale Ancyrocephalus parupenei Benedenia hawaiiensis Haliotrema brotulae Haliotrema curvicirrus Haliotrema bifurcocirrus Benedenia hawaiiensis Haliotrema pervagoris Haliotrema rectangulare Microcotyle polymixiae Haliotrema bisegmentatum Haliotrema pterophallus Pseudobenedenia elongata Pseudobenedenia ovalis Enoplocotyle hawaiiensis Diplectanum priacanthi Benedenia hawaiiensis Haliotrema priacanthi

Pristipomoides microlepis (18)

Pseudallobenedenia

Parexocoetus brachypterus (1) Parupeneus chryserydros (2)

Parupeneus multifasciatus (40)

Parupeneus pleurostigma (20)

Parupeneus porphyreus (15)

Pervagor spilosoma (4)

Polymixia japonicus (6) Pomacentrus jenkinsi (8) Priacanthus boops (5)

197

(Goto,

(Goto,

opakapaka Yamaguti,

1966

198

Pristipomoides sieboldii (20)

Promethichthys promethens (10) Scarus sordidus (8) Scomber japonicus (20) Scomberoides sancti-petri (6) Seriola dumerilii (12) Sphyraena barracuda (9) Sphyraena helleri (23) Sphyrna lewini (20) Strongylura gigantea (2) Synodus dermatogenys (14) Tetrapterus angustirostris (2)

Thunnus alalonga (2) Trachurops crumenophthalmus (70) Xanthichthys rìngens (5) Xiphias gladius (8) Zanclus canescens (50)

Zebrasoma flavescens (14) Zebrasoma veliferum (6)

Pseudodiscocotyla opakapaka Yamaguti, 1965 Diplectatium opakapaka Pseudobenedenia elongata Diplectatium curvivagina Diplectanum opakapaka Pseudodiscocotyla opakapaka Yamaguti, 1965 Gempylitrema longipedunculatum Benedenia hawaiiensis Benedenia scari Kuhnia scombri (Kuhn, 1829) Allodiscocotyla lae Aspinatrium kahala VaUisiopsis sphyraenae Pseudochauhanea sphyraenae Yamaguti, 1965 Metopisthogyne sphyraenae Yamaguti, 1966 Erpocotyle sphyrnae (MacCallum, 1931) Pseudohaliotrematoides recurvatus Axinoides strongylurae Benedenia hawaiiensis Capsala ovalis (Goto, 1894) Capsaloides cristatus Capsaloides nairagi Capsaloides tetrapteri Capsala nozawae (Goto, 1894) Hexostoma sibi Gastrocotyle trachuri van Beneden et Hesse, 1863 Pseudaxine decapteri Benedenia hawaiiensis Tristoma adintegrum Tristoma adcoccineum Haliotrema canescens Haliotrema tubulovagina Haliotrema zancli Pseudohaliotrematoides zancli Haliotrema brotulae Haliotrema macracantha Haliotrema macracantha

5 1 Summary

Of the total of 147 species collected, including those reported in Pacific Science (1965 and 1966) as representing new genera, 107 were considered to be new, and the remaining 40 are either cosmopolitan or are already known from Hawaiian waters and the Atlantic Ocean in accordance with the wide distribution of their hosts. Considerable host-specificity is suggested by the host-parasite records for some species, whereas Benedenia hawaiietisis (Capsalidae) and Enoplocotyle hawaiiensis (Microbothriidae) were found on 24 and on 8 different host species, respectively. Such polyxenous parasitism has been observed in some Digenea from Hawaii, also. It is really surprising that the Hawaiian fauna of the Monogenea is unusually rich in ancyrocephaline species, in accordance with the abundance of offshore and littoral fishes. Most of these helminths are highly host-specific and appear to show a pronounced endemic character, probably as a result of the long isolation of their host population. Unfortunately, no extensive investigation comparable with ours has been carried out for this group of Monogenea in other waters. I suggest that a wide field in research upon the dactyogyrid Monogenea awaits the attenten of future taxonomists, as does that upon the didymozoid Digenea. A great deal of technical dexterity is required, however, for exploration in this fascinating field. Two new names, Nasicola and Alloheterocotyla, are proposed as new combinations. Keys are given for those genera that are represented by three or more species. A host-parasite list is appended, arranged in alphabetical order of host names.

ABBREVIATIONS USED IN FIGURES AB AC AG AM AO AP AR AS AVGD BC BE C CA CL CP CS CV DA DE DS E ES GA GB GD GI GO GP GT HG HO I IB ID M MB MC

atrial bulb accompanying cell apical gland atrial muscle apical organ accessory piece atrial ring atrial spine accessory vaginal duct bulbus cirri bulbus ejaculatorius cirrus caudal appendage haptoral clamp cirrus pouch cirrus spine circumvaginal pouch dorsal anchor ductus ejaculatorius ductus seminalis egg esophagus genital atrium genital bulb germiduct genito-intestinal duct Goto's organ or gland genital pore gonotyl head gland head organ intestine intestinal branch intestinal diverticle mouth median bar muscle cylinder

MH O OC OH OS OT P PC PD PG PH PL PP PR PV PVL RS S SB SC SD SG SP T U UD UP V VA VD VGD VP VR VT VTD W •

marginal hooklet ovary eyespot opisthohaptor oral sucker oo type pharynx prostatic cell prostatic duct vaginal peg prohaptor papilla pars prostatica prostatic reservoir prostatic vesicle postvaginal lobe receptaculum seminis sucker submedian bar sheath of cirrus squamodisc shell gland sphincter testis uterus uterine duct uterine pore vagina ventral anchor vas deferens vaginal duct vaginal pore vitelline reservoir vitelline gland vitelline duct window canalis receptaculi sem

Plates

202

PLATE I

FIGURE

i

Benedenia bodiani n. sp. A holotype, ventral view B haptoral anchors of para type C terminal genitalia of holotype, ventral view D egg of paratype

FIGURE

2

Benedenia hawaiiensis n. sp. A holotype, ventral view B haptoral anchors of holotype C terminal genitalia of paratype, ventral view

FIGURE

3

Benedenia lolo n. sp. A holotype, ventral view B haptoral anchors of holotype C terminal genitalia of holotype, ventral view

FIGURE

4

Benedenia scan n. sp. A holotype, ventral view B haptoral anchors of holotype C terminal genitalia of paratype, ventral view

204

P L A T E II

FIGURE 5

Pseudobenedertia elongata n. sp. A holotype, ventral view B haptoral anchors of holotype C terminal genitalia of paratype, ventral view

FIGURE 6

Pseudobenedetiia merinthe n. sp. A holotype, ventral view B haptoral anchors of paratype C terminal genitalia of paratype, ventral view

FIGURE 7

Pseudobenedetiia ovalis n. sp. A holotype, ventral view B haptoral anchors of holotype C terminal genitalia of holotype, ventral view

P L A T E III

FIGURE

8

Allobenedenia epinepheli n. sp. A holotype, ventral view B haptoral anchors of holotype

FIGURE

9

Pseudallobenedenia apharei Yamaguti, 1966 A holotype, ventral view B haptoral anchors of paratype

FIGURE

10

Pseudallobenedenia opakapaka Yamaguti, 1966 A holotype, ventral view B haptoral anchors of paratype

FIGURE 1 1

Lagenivaginopseudobenedenia etelis Yamaguti, 1966 A holotype, ventral view B haptoral anchors of holotype

2o8

PLATE IV

FIGURE 12

Dioncopseudobenedenia kala Yamaguti, 1965 A holotype, ventral view B haptoral anchors of paratype C Goto's gland D prostate cells extensively developed among vitelline follicles in holotype

FIGURE 13

Dioncopseudobenedenia macracantha n. sp. A holotype, ventral view B haptoral anchors of paratype C terminal genitalia of holotype, ventral view D prostate cells developed among vitelline follicles

FIGURE 14

Oligoncobenedenia nasonis Yamaguti, 1965 A holotype, ventral view B hapotoral anchors of paratype

FIGURE 15

Capsala gotoi n. sp. A holotype, ventral view B haptoral anchors of holotype C marginal teeth of holotype D showing arrangement of marginal teeth E terminal genitalia of holotype, ventral view

PLATE V

FIGURE

16

Capsah neothuntii n. sp. A holotype, ventral view B haptoral anchors of holotype C marginal teeth of paratype D showing arrangement of marginal teeth E terminal genitalia of holotype, ventral F egg of paratype

FIGURE

17

Capsala nozawae (Goto, 1894) A entire worm, ventral view B haptoral anchors C terminal genitalia D egg

FIGURE

18

Capsala oralis (Goto, 1894) A entire worm, ventral view B haptoral anchor C marginal teeth D terminal genitalia, ventral view E egg

212

PLATE VI

FIGURE

19

Capsala (Caballerocotyla) biparasitica (Goto, 1894) A holotype, ventral view B haptoral anchors C marginal tooth D showing arrangement of marginal teeth E terminal genitalia F egg

FIGURE

20

Capsaloides cristatus n. sp. A holotype, ventral view B haptoral hook of holotype C marginal teeth of holotype D terminal genitalia of holotype, ventral view E egg of paratype

FIGURE

21

Capsaloides istiophori n. sp. A holotype, ventral view B haptoral anchors of paratype C marginal teeth of paratype D terminal genitalia of paratype, ventral view E egg of paratype

214

PLATE VII

FIGURE 22

Capsaloides nairagi n. sp. A holotype, ventral view B haptoral anchors of holotype C marginal teeth of holotype D terminal genitalia of holotype, ventral view E egg of paratype

FIGURE 23

Capsaloides sinuatus (Goto, 1894) A haptoral anchors B marginal teeth C terminal genitalia, ventral view D egg

FIGURE 24

Capsaloides tetrapteri n. sp. A holotype, ventral view B haptoral anchors of paratype C marginal hooklet of paratype D marginal teeth of paratype E terminal genitalia of paratype, dorsal view

2x6

PLATE VIII

FIGURE 25

Tristoma adcoccineum n. sp. A holotype, ventral view B haptoral anchors of para type C marginal teeth of paratype D showing arrangement of marginal teeth E terminal genitalia of paratype, ventral view F egg of paratype

FIGURE 26

Tristoma adintegrum n. sp. A holotype, ventral view B haptoral anchors of paratype C marginal teeth of paratype D showing arrangement of marginal teeth in paratype E terminal genitalia of paratype, ventral view

FIGURE 27

Nasicola klawei (Stunkard, 1962) n. comb. A entire worm, ventral view B haptoral anchors C inner marginal teeth D outer marginal teeth E terminal genitalia, ventral view F egg

2l8

P L A T E IX

FIGURE

28

Pseudotiitzschia uku Yamaguti, 1965 A holotype, ventral view B egg of paratype

FIGURE

29

Enoplocotyle hawaiiensis n. sp. A holotype, ventral view B haptoral hooks of holotype C copulatory organ of holotype

FIGURE

30

Diploheterocotyla dasyatis Yamaguti, 1965 A holotype, ventral view B haptoral anchors of holotype

FIGURE

31

Alloheterocotyla aetobatis (Hargis, 1955) n. comb. A entire worm, ventral view B haptoral anchors C cirrus D egg

FIGURE

32

Ancyrocephalus ornatus n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view C egg of paratype

220

PLATE X

FIGURE 33

Ancyrocephalus parupenei n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype C egg of paratype

FIGURE 34

Ancyrocephalus pauu n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view C egg of paratype

FIGURE 35

Haliotrema acanthuri n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

Haliotrema amanses n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view

36

35A

222

P L A T E XI

FIGURE

37

Haliotrema angulare n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype C egg of paratype

FIGURE

38

Haliotrema angulocirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, dorsal view

FIGURE

39

Haliotrema atinulocirrus n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, ventral view

FIGURE

40

Haliotrema bifurcocirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

41

Haliotrema bisegmentatum n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view

224

P L A T E XII

FIGURE 42

Haliotrema bodiani n. sp. A genitalia of paratype, dorsal view B anchor apparatus of holotype, dorsal view

FIGURE 43

Haliotrema brotulae n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view

FIGURE 44

Haliotrema caesiopercae n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view

FIGURE 45

Haliotrema canescens n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 46

Haliotrema centropygis n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

226

P L A T E XIII

FIGURE

47

Haliotrema chelicirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

48

Haliotrema chromidis n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

49

Haliotrema ctenochaeti n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view C cirrus of paratype, ventral view

FIGURE

50

Haliotrema curvicirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

51

Haliotrema epinepheli n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view C cirrus and uterus of paratype, ventral view

228

PLATE XIV

FIGURE

52

Haliotrema flagellatum n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

53

Haliotrema flexicirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

54

Haliotrema lactoriae n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view

FIGURE

55

Haliotrema macracantha n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

56

Haliotrema microphallus n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view

230

PLATE X V

FIGURE 57

Haliotrema minutospirale n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view

FIGURE 58

Haliotrema palmatum n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 59

Haliotrema pervagoris n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 60

Haliotrema priacanthi n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 61

Haliotrema pterophallus n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view C copulatory organ of holotype, ventral view

FIGURE 62

Haliotrema rectangulare n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

57A

59 a

59s

232

PLATE XVI

FIGURE 63

Haliotrema scyphovagina n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 64

Haliotrema serpenticirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 65

Haliotrema sigmoidocirrus n. sp. A genitalia of holotype, dorsal view B anchor apparatus of holotype, dorsal view

FIGURE 66

Haliotrema spiculare n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view

FIGURE 67

Haliotrema spirale n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, dorsal view C egg of paratype

FIGURE 68

Haliotrema tubulovagina n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, dorsal view

334

PLATE XVII

FIGURE

69

Haliotrema zancli n. sp. A holotype, dorsal view B anchor apparatus of paratype, dorsal view C copulatory organ of paratype, dorsal view

FIGURE

70

Cleithrarticus bulbovagina n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, dorsal view

FIGURE

71

Cleithrarticus cleithrarticus Mizelle, 1963 A genitalia, dorsal view B anchor apparatus, ventral view

FIGURE

72

Pseudancyrocephalus kala n. g., n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view

PLATE XVIII

FIGURE

73

Pseudancyrocephalus duplicatus n. sp. A holotype, ventral view B copulatory organ of holotype, ventral view C egg of paratype

FIGURE

74

Pseudancyrocephalns longicirrus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

75

Pseudancyrocephalus longispicularis n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE

76

Pseudancyrocephalus nasonis n. sp. A holotype, ventral view B male terminal genitalia of paratype, dorsal C egg of paratype

338

PLATE XIX

FIGURE 77

Neohaliotrema maomao Yamaguti, 1965 A holotype, dorsal view B copulatory organ of holotype, dorsal view C egg of paratype

FIGURE 78

Pseudohaliotrematoides aurigae n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view C egg of paratype

FIGURE 79

Pseudohaliotrematoides falcatus n. sp. A genitalia of paratype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 80

Pseudohaliotrematoides microphallus n. sp. A genitalia of holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 81

Pseudohaliotrematoides recurvatus n. sp. A genitalia of paratype, dorsal view B anchor apparatus of holotype, ventral view C cirrus of paratype, ventral view

240

PLATE XX

FIGURE 82

Pseudohaliotrematoides triangulovagina n. sp. A genitalia of holotype, ventral view B anchor apparatus of paratype, ventral view C copulatory organ of paratype, ventral view

FIGURE 83

Pseudohaliotrematoides zancli n. sp. A holotype, ventral view B anchor apparatus of holotype, ventral view C copulatory organ of holotype, ventral view

FIGURE 84

Paraticyrocephaloides dactylopteri n. sp. A holotype, dorsal view B anchor apparatus of holotype, dorsal view C terminal genitalia of holotype, dorsal view

242

PLATE XXI

FIGURE 85

Murraytrematoides kuhliae n. sp. A holotype, ventral view B anchor apparatus of holotype, ventral view C terminal genitalia of paratype, dorsal view D vagina of paratype, dorsal view

FIGURE 86

Pseudempleurosoma carangis Yamaguti, 1965 A holotype, ventral view B anchor apparatus of holotype, ventral view

FIGURE 87

Nasobranchitrema pacificum Yamaguti, 1965 A holotype, ventral view B anchor apparatus of paratype, ventral view

FIGURE 88

Diplectanum curvivagina n. sp. A genitalia of holotype, dorsal view B opisthohaptor of paratype, ventral view

244

P L A T E XXII

FIGURE 89

Diplectanum diplobulbus n. sp. A genitalia of holotype, ventral view B opisthohaptor of paratype, dorsal view

FIGURE 90

Diplectanum kuhliae n. sp. A genitalia of holotype, dorsal view B opisthohaptor of paratype, ventral view C egg of paratype

FIGURE 91

Diplectanum nenne n. sp. A genitalia of holotype, ventral view B opisthohaptor of holotype, ventral view

FIGURE 92

Diplectanum opakapaka n. sp. A holotype, ventral view B opisthohaptor of holotype, ventral view C genitalia of holotype, ventral view

246

P L A T E XXIII

FIGURE

93

Diplectanum priacanthi n. sp. A genitalia of holotype, ventral view B opisthohaptor of paratype, dorsal view C egg of paratype

FIGURE

94

Diplectanum querni n. sp. A genitalia of paratype, ventral view B opisthohaptor of holotype, ventral view

FIGURE 9 5

FIGURE

96

Diplectanum spiculare n. sp. A genitalia of holotype, ventral view B opisthohaptor of paratype, dorsal view Lamellodiscus epsilon n. sp. A holotype, ventral view B opisthohaptor of paratype, ventral view C genitalia of holotype, ventral view D egg of holotype

PLATE XXIV

FIGURE 97

Acleotrema kyphosi n. sp. A holotype, ventral view B genitalia of paratype, ventral view C posterior extremity of paratype, ventral view D genital atrium showing saw-teeth in paratype, ventral

FIGURE 98

Gempylitrema longipedunculatum n. g., n. sp. A holotype, ventral view B anterior extremity of holotype, ventral view C clamp of holotype, ventral view D ovarian complex of paratype, ventral view E terminal genitalia of paratype, ventral view

250

PLATE X X V

FIGURE

99

Pseudodiclidophora decapteri Yamaguti, 1965 A holotype, ventral view B clamp of paratype, ventral view C male terminal genitalia of paratype, ventral view D egg of paratype

FIGURE

100

Allopseudodiclidophora opelu Yamaguti, 1965 A holotype, ventral view B clamp of holotype, ventral view C—E caudal anchors of holotype F male terminalia of holotype, ventral view

FIGURE

101

Mlodiscocotyla lae n. sp. A holotype, ventral view B clamp of holotype, ventral view C caudal anchors of holotype D male terminal genitalia of holotype, ventral view E egg of paratype

PLATE XXVI

FIGURE

102

Pseudopisthogyne lepidocybii Yamaguti, 1965 A holotype, ventral view B larger caudal anchor of paratype C - D large and small clamps of holotype, ventral E terminal genitalia of holotype, ventral view F vagina and its ducts of paratype, ventral view

FIGURE

103

Allopseudopisthogyne constricta Yamaguti, 1965 A holotype, ventral view B larger caudal anchor of holotype C - D large and small clamps of paratype E terminal genitalia of paratype, ventral view F vagina and its ducts of paratype, ventral view

=54

PLATE XXVII

FIGURE

104

FIGURE

105

Metopisthogyne sphyraenae Yamaguti, 1966 A holotype, ventral view B caudal anchors of paratype C vagina of paratype, ventral view Pseudopisthogynopsis lepidocybii Yamaguti, 1965 A holotype, ventral view B—C large and small clamps of paratype D terminal genitalia of paratype, ventral view E vagina and its ducts of holotype, ventral view

256

PLATE XXVIII

FIGURE 106

Vallisiopsis sphyraenae n. sp. A holotype, ventral view B clamp of holotype, ventral view G caudal anchors of paratype D terminal genitalia of paratype, ventral view E vagina of holotype, ventral view

FIGURE 107

Holotype of Pseudodiscocotyla opakapaka Yamaguti, 1965, dorsal view

FIGURE 108

Hexostoma keokeo n. sp. A holotype, ventral view B larger sucker-like clamp of paratype, ventral view C caudal anchors of paratype D terminal genitalia, including vagina, of paratype, ventral view

258

PLATE XXIX

FIGURE 109

Hexostoma sibi n. sp. A holotype, ventral view B - C large and small sucker-like clamps of para type, ventral view D caudal anchors of paratype E terminal genitalia, including vagina, of paratype, ventral view

FIGURE 110

Neohexostoma kawakawa n. sp. A holotype, ventral view B sucker-like clamp of paratype, ventral view C caudal anchors of holotype D terminal genitalia, including vagina, of paratype, ventral view

FIGURE 111

Kuhnia scombri (Kuhn, 1829), vagina and shell gland complex, dorsal view

FIGURE 112

Protomicrocotyle celebesensis Yamaguti, 1953, ventral view

18IÊ ilfl O

Wßig§ vi •

Ml®

2ÓO

PLATE XXX

FIGURE

113

Neomicrocotyle carangis n. sp. A holotype, ventral view B caudal anchors of holotype C terminal genitalia of paratype, ventral view D atrial spine

FIGURE

114

Pseudopterinotrema albulae Yamaguti, 1966, holotype, ventral view

FIGURE

115

Terminal genitalia of Axine belones Abildgaard, 1794, ventral view (uterus not shown)

FIGURE

116

Axine depauperati n. sp. A holotype, ventral view B clamp of holotype, ventral view C larval hooklets D terminal genitalia of paratype, ventral view (uterus not shown) E vagina of paratype, dorsal view

262

PLATE XXXI

FIGURE 117

Axine spilonotopteri n. sp. A holotype, dorsal view B anterior extremity of holotype, dorsal view C clamp of paratype D larval hooklet E terminal genitalia of paratype, dorsal view (uterus not shown) F anterior atrial spines G posterior atrial spines H vagina of holotype, dorsal view I egg of paratype

FIGURE 118

Axinoides bulbosus n. sp. A holotype, ventral view B clamp of holotype C larval hooklet D terminal genitalia of paratype, ventral view (uterus not shown)

FIGURE 119

Axinoides diploporus n. sp. A holotype, ventral view B clamp of paratype C larval hooklet D male terminalia of paratype, dorsal view E female terminalia of paratype, dorsal view F vagina of paratype, dorsal view

264

PLATE XXXII

FIGURE

120

Female genitalia of Axinoides kola Unnithan, 1957, ventral view

FIGURE

121

Axinoides strongylurae n. sp. A holotype, ventral view B clamp of holotype C larval hooklets D terminal genitalia of holotype, ventral view E vagina of paratype, ventral view

FIGURE

122

Male terminalia of Allopseudaxine katsuwonis (Ishii, 1936)

FIGURE

123

Allopseudaxine yaito n. sp. A holotype, ventral view B clamp of holotype, ventral view C caudal anchors of paratype D terminal genitalia of holotype, ventral view (uterus not shown)

FIGURE

124

Allopseudaxinoides euthynni Yamaguti, 1965 A holotype, ventral view B clamp of holotype, ventral view

FIGURE

125

Allopseudaxinoides vagans (Ishii, 1936) n. comb. A clamp skeleton, ventral view B terminal genitalia, ventral view

266

P L A T E XXXIII

FIGURE

126

Allomonaxine carangoides Yamaguti, 1965 A holotype, ventral view B terminal genitalia of paratype, ventral view C vagina of paratype, dorsal view

FIGURE

127

Heteraxinoides caprodontis n. sp. A holotype, ventral view B clamp of holotype C terminal genitalia of holotype, ventral view (uterus not shown)

FIGURE

128

Sibitrema poonui Yamaguti, 1966 A holotype, ventral view B caudal anchors of paratype C egg of paratype

FIGURE

129

Cypselurobranchitrema spilonotopteri Yamaguti, 1966, holotype, ventral view

268

PLATE XXXIV

FIGURE

130

Cemocotylella carangis n. sp. A holotype, ventral view B clamp on long side of paratype C clamp on short side of paratype D caudal anchors of paratype E terminal genitalia of adult paratype (uterus not shown)

FIGURE 1 3 1

Male terminalia of Gastrocotyle trachuri van Beneden et Hesse, 1863

FIGURE

132

Pseudaxine decapteri n. sp. A holotype, ventral view B clamp of paratype C larger caudal anchors D smaller apical anchors E terminal genitalia of holotype, ventral view (uterus not shown)

FIGURE

133

Pseudochauhanea sphyraenae Yamaguti, 1965 A holotype, ventral view B clamp of paratype C vagina and its accessory ducts of paratype, dorsal view

270

PLATE XXXV

FIGURE 134

Neothoracocotyle acanthocybii (Meserve, 1938) A entire worm cut into two pieces, dorsal view B clamp C caudal anchors D genial atrium armed with numerous acicular spines, ventral view E acicular atrial spine F ovarian complex, dorsal view

FIGURE 135

Areotestis sibi Yamaguti, 1965 A holotype, dorsal view B clamp of paratype, dorsal view C caudal anchors of holotype D terminal genitalia of paratype, ventral view

PLATE XXXVI

FIGURE 136

Microcotyle bothi N. sp. A holotype, dorsal view B clamp of holotype C terminal genitalia of paratype D egg of paratype

FIGURE 137

Microcotyle emmelichthyops n. sp. A holotype, ventral view B clamp of holotype C terminal genitalia of holotype, ventral view

FIGURE 138

Microcotyle polymixiae n. sp. A holotype, ventral view B clamp of paratype C terminal genitalia of holotype, ventral view D egg of paratype

274

PLATE XXXVII

FIGURE

139

Aspinatrium kahala n. sp. A holotype, dorsal view B clamp of holotype C terminal genitalia of holotype, dorsal view (uterus not shown) D vagina of paratype, ventral view

FIGURE

140

Bivagina kyphosi n. sp. A holotype, dorsal view B clamp of paratype C terminal genitalia of paratype, ventral view (uterus not shown)

FIGURE

141

Metamicrocotyla mugilis n. sp. A holotype, ventral view B clamp of holotype C anterior extremity of holotype, ventral view D terminal genitalia of paratype, ventral view

276

PLATE XXXVIII

FIGURE

142

Prostatomicrocotyla kuhliae n. g., n. sp. A holotype, dorsal view B clamp of paratype C terminal genitalia of paratype, ventral view

FIGURE

143

Prostatomicrocotyla maomao n. sp. A holotype, ventral view B clamp of holotype, ventral view C terminal genitalia of paratype, ventral view

PLATE XXXIX

FIGURE 144

Allomicrocotyla onaga Yamaguti, 1965 A holotype, ventral view B clamp of paratype, dorsal view C caudal anchors of holotype D terminal genitalia of holotype, ventral view

FIGURE 145

Hexabothrium dasyatis n. sp. A holotype, dorsal view B posterior sucker C anchor on caudal appendage of holotype D terminal genitalia, including vagina, of paratype, ventral

FIGURE 146

Erpocotyle sphyrnae (MacCallum, 1931), ventral view

FIGURE

Lobatostoma albulae n. sp., holotype, ventral view

147

References

1952. Some Chilean monogenetic trematodes. Rep. Lund Univ. Chile Exped. 1948-1949. Lunds Univ. Àrsskr. n. F. Avd. 2, 4 7 ( 1 1 ) , 26 pp. BYCHOWSKY, B. E. 1957. Monogenetic trematodes, their systematics and phytogeny. Akad. Nauk SSSR, 1-509. Translated from Russian by W . }. Hargis, Jr., AIBS, Washington, D . C . BYCHOWSKY, B. E., and L. F. NAGIBINA. 1954. New monogenetic trematodes from the Pacific Ocean. [In Russian] Zool. Zhum. 33(1) :30-38. CERFONTAINE, p. 1899. Les Onchocotylinae (Contribution â l'étude des Octocotylides, V ) . Arch. Biol. 16:345-478. DELAROCHE, F. D. 1811. Sur deux animaux vivant sur les branchies des poissons. Nouv. Bull. Sci. Philom. Paris 2(44) :2-JO~2-JII. DILLON, w . A., and w. j . HARGIS, JR. 1965. Monogenetic trematodes from the Southern Pacific Ocean, I. Monopisthocotyleids from New Zealand fishes. Biol. Antarct. Sea, 2. Antarctic Res. Ser. 5:229-249. 1965. Idem, II. Polyopisthocotyleids from New Zealand fishes. The families Discocotylidae, Microcotylidae, Axinidae and Gastrocotylidae. Ibid., 251-280. GOTO, s. 1894. Studies on the ectoparasitic trematodes of Japan. J. Coll. Sci. Tokyo 8:1-273. HARGIS, w. j., JR. 1955. Monogenetic trematodes of Gulf of Mexico fishes, Part IV. The superfamily Capsaloidea Price, 1936. Rev. Ibér. Par. Vol. Extr. 116. 1956. Monogenetic trematodes of Gulf of Mexico fishes, Part X . T h e BRINKMAN, A., JR.

family Microcotylidae Taschenb.,

1879. Trans. Amer. Microsc.

Soc.

75(4) :43^~4531956. Monogenetic trematodes of Gulf of Mexico fishes, Part XII. The family Gastrocotylidae Price, 1943. Bull. Mar. Sci. Gulf and Caribbean 6(i}:28~43. HARGIS, w . j., JR., and w . A. DILLON. 1965. Monogenetic trematodes from the Southern Pacific Ocean, Part III. Diplasiocotyle johtistoni Sandars, 1944 from New Zealand and Australia, with description of a new family. Proc. Helm. Soc. Wash. 32(2) :22o-224. ISHII, N. 1936. Some new ectoparasitic trematodes of marine fishes. Zool. Mag. Tokyo 48:783-786. JOHNSTON, T. H. 1931. New trematodes from the subantarctic and antarctic. Austral. J. Exp. Biol. Med. Sci. 8:91-98. JOHNSTON, T. H., and 0. w . TIEGS. 1922. New gyrodactylid trematodes from Australian fishes together with a reclassification of the superfamily Gyrodactyloidea. Proc. Linn. Soc. N . S. Wales 47:83-131. LINTON, E. 1907. Notes on parasites of Bermuda fishes. Proc. U. S. Nat. Mus. 33:85-126. 1940. Trematodes from fishes, mainly from the Woods Hole region, Massachusetts. Proc. U. S. Nat. Mus. 88:1-172.

282

Further notes on the genus Microcotyle. Zool. Jb. Syst. 3 5 : 3 8 9 - 4 0 2 . 1915. Some new species of ectoparasitic trematodes. Zoologica, N. Y.

MACCALLUM, G. A. 1 9 1 3 .

1:393-410.

1916. Some new species of parasitic trematodes from marine fishes. Zoopathologica 1 : 3 - 3 8 . 1931. Four new species of trematode worms of the subfamily Onchocotylinae. Proc. U. S. Nat. Mus. 79:1-8. MESERVE, F. G. 1 9 3 8 . List of twenty-two species of monogenetic trematodes from the South Pacific. Proc. Minnesota Acad. Sci. 6:58. MIZELLE, j . D. 1 9 6 3 . Studies on monogenetic trematodes, XXIV. A new dactylogyrid genus from Acanthurus olivaceus Bloch. J. Parasitol. 49(5): 75 2 -753MIZELLE, J . D., and c. E. PRICE. 1 9 6 5 . Studies on monogenetic trematodes, XXVIII. Gill parasites of the piranha with proposal of Anacanthorus gen. n. J. Parasitol. 5 i ( i ) : 3 o - 3 6 . PARONA, C., and A. PERUGIA. 1 8 8 9 . Di alcuni trematodi ectoparassiti di pesci marini. (Nota prev.) Ann. Mus. Stor. Nat. Genova 2 7 : 7 4 0 - 7 4 7 . PRICE, E. w. 1 9 3 8 . North American monogenetic trematodes, II. TTie families Monocotylidae, Microbothriidae, Acanthocotylidae, and Udonellidae (Capsaloidea). J. Wash. Acad. Sci. 2 8 : 1 0 9 - 1 2 6 . 1939. North American monogenetic trematodes, III. The family Capsalidae (Capsaloidea). Ibid. 2 9 : 6 3 - 9 2 . I 9 6 0 . Idem, VIII. The family Hexostomatidae. Proc. Helm. Soc. Wash. 2 8 ( i ) : 4 - 9 . 1962. Idem, X. The family Axinidae. Ibid. 29(1):!—18. 1962. Idem, XI. The family Heteraxinidae. J. Parasitol. 48(3) :402418.

1962. Redescription of two exotic species of monogenetic trematodes and the proposal of a new family. Proc. Biol. Soc. Wash. 7 5 : 2 9 5 - 3 0 2 . RAMALINGAM, K. 1 9 6 1 . On a new species of the genus Heteraxine (Monogenea: Axinidae) from the gills of Caranx kalla Cuv. et Val. Mag. Nat. Hist. 13 s. 4 ( 3 7 ) : 1 - 5 . SETTI, E. 1 8 9 8 . Tristomum perugiae n. sp., sulle brachie del Tetrapterus belone Raf. Arch. Parasitol. Paris 1 : 3 0 8 - 3 1 3 . SPROSTON, N. G. 1 9 4 5 . The genus Kuhnia n. g. (Trematoda:Monogenea). An examinataion of the value of some specific characters, including factors of relative growth. Parasitology 3 6 : 1 7 6 - 1 9 0 . 1946. A synopsis of the monogenetic trematodes. Trans. Zool. Soc. London 2 5 ( 4 ) : 1 8 5 - 6 0 0 . STUNKARD, H. w. 1 9 6 2 . CaballeTocotyh.1 khwei sp. nov., a monogenetic trematode from the nasal capsule of Neothunnus macropterus. J. Parasitol. 4 8 ( 6 ) : 88 3 - 8 9 0 .

Vallisiopsis contorta n. g. and n. sp. and Gastrocotyle indica n. sp., monogenetic trematodes from marine fishes of the Madras coast. Parasitology 4 1 ( 3 - 4 ) : 1 6 2 - 1 6 5 . TAGLIANI, G. 1 9 1 2 . Enoplocotyle minima nov. gen., nov. sp., trematode monogenetico parassita sulla cute di Muraena Helena L. Rich, anatom. e sistem. Arch. Zool. Napoli 5 : 2 8 1 - 3 1 8 . TASCHENBERG, E. O. 1 8 7 9 . Zur Systematik der monogenetischen Trematoden. Z. Naturw. Berlin 5 2 : 2 3 2 - 2 6 5 . UNNITHAN, R. v. 1 9 5 7 . On the functional morphology of a new fauna of Monogenea on fishes from Trivandrum and environs, Part I. Axinidae fam. nov. Bull. Centr. Res. Inst. Univ. Kerala 5 ( 2 ) : 2 7 - 1 2 2 . SUBHAPRADHA, G. K. 1 9 5 1 .

283

1962. Idem, Part II. Opisthogynidae fam. nov. (Gastrocotyloidea). Parasitology 5 2 : 3 1 5 - 5 5 1 . YAMAGUTI, s. 1934. Studies on the helminth fauna of Japan, Part 2. Trematodes of fishes, I. Jap. J. Zool. 5(3) :249~54i. 1937. Idem, Part 19. Fourteen new ectoparasitic trematodes of fishes. Publ. by author. 28 pp. 1938. Idem, Part 24. Trematodes of fishes, V . Jap. J. Zool. 8 ( 1 ) : 1953. Parasitic worms mainly from Celebes, Part 2. Monogenetic trematodes of fishes. Acta Med. Okayama 8:203-256. 1963. Systema helminthum, Vol. IV. Monogenea and Aspidocotylea. Interscience Publishers, New York. 699 pp. 1965. New monogenetic trematodes from Hawaiian fishes, I. Pacif. Sci. 1 9 ( 1 ) : 55~951966. New monogenetic trematodes from Hawaiian fishes, II. Ibid. 20(4) =419-434.

Index

Abortipedia Unnithan, 1962, 149 Acleotrema kyphosi n. sp., 124 Allobenedenia epinepheli n. sp., 27 Allodiscocotylinae Tripartii, 1959, 130 Allodiseocotyla lae n. sp., 130 Alloheterocotyla n. g., 60 Alloheterocotyla aetobatìs (Hargis, 1955), 59 Allomicrocotyla onaga Yamaguti, 1965, 188 Allomicrocotylidae Yamaguti, 1965, 188 Allomonaxine caragoides Yamaguti, 1965, 165 Allopseudaxine katsuwonis (Ishii, 1936), 161 Allopseudaxine yaito n. sp., 161 Allopseudaxininae Yamaguti, 1963, 161 Allopseudaxinoides euthynni Yamaguti, 1965, 162 Allopseudaxinoides vagans (Ishii, 1936), 164 Allopseudodiclidophora opelu Yamaguti, 1965, 129 Allopseudodiclidophorinae Yamaguti, 1965, 129 Allopseudopisthogyne constricta Yamaguti, 1965, 134 Ancyrocephalinae Bychowsky, 1937, 61 Ancyrocephalus parupenei n. sp., 62 Ancyrocephalus pauu n. sp., 62 Ancyrocephalus ornatus n. sp., 61 Areotestinae Yamaguti, 1965, 176 Areotestis sibi Yamaguti, 1965, 176 Aspidocotylea Monticelli, 1892, 192 Aspidogasteridae Poche, 1907, 192 Aspidogasterinae Chauhan, 1954, 192 Aspinatrium kahala n. sp., 181 Axine belones Abildgaard, 1794, 152 Axine depauperati n. sp., 153 Axine spilonopteri n. sp., 154 Axinidae Unnithan, 1957, 152 Axininae Monticelli, 1903, 152 Axinoides bulbosus n. sp., 156 Axinoides diploporus n. sp., 157 Axinoides kala Unnithan, 1957, 158 Axinoides strongylurae n. sp., 159 Benedenia bodiani n. sp., 19 Benedenia hawaiiensis n. sp., 20

Benedenia lolo n. sp., 21 Benedenia scari n. sp., 23 Benedeniinae Johnston, 1931, 19 Bivagina kyphosi n. sp., 182 Capsala gotoi n. sp., 36 Capsala neothunni n. sp., 37 Capsala nozawae (Goto, 1894), 39 Capsala ovalis (Goto, 1894), 40 Capsala (Caballerocotyla) biparasitica (Goto, 1894), 40 Caballerocotyla klawei Stunkard, 1962, 53 Capsalidae Baird, 1853, 19 Capsalinae Johnston, 1929, 36 Capsaloidea Price, 1936, 19 Capsaloides cristatus n. sp., 42 Capsaloides istiophori n. sp., 43 Capsaloides nairagi n. sp., 45 Capsaloides sinuatus (Goto, 1894), 46 Capsaloides tetrapteri n. sp., 48 Cemocotylella carangis n. sp., 170 Cemocotylidae Yamaguti, 1963, 170 Cleithrarticus bulbovagina n. sp., 96 Cleithrartìcus cleithrarticus Mizelle, 1963, 97 Cypselurobranchitrema spilonopteri Yamaguti, 1966, 169 Cypselurobranchitrematinae Yamaguti, 1966, 169 Dactylogyridae Bychowsky, 1933, 6i Dactylogyroidea Yamaguti, 1963, 61 Diclidophoridae Cerfontaine, 1895, 125 Diclidophoroidea Price, 1936, 125 Dioncopseudobenedenia kala Yamaguti, 1965, 33 Dioncopseudobenedenia macracantha n. sp., 34 Diplectanidae Bychowsky, 1957, 1 1 4 Diplectanum curvivagina n. sp., 1 1 6 Diplectanum diplobulbus n. sp., 1 1 6 Diplectanum kuhliae n. sp., 1 1 7 Diplectanum nenue n. sp., 1 1 8 Diplectanum opakapaka n. sp., 1 1 9 Diplectanum priacanthi n. sp., 120 Diplectanum quemi n. sp., 1 2 1 Diplectanum spiculare n. sp., 1 2 1

286

Diploheterocotyla dasyatis Yamaguti, 1965, 58 Discocotylidae Price, 1936,130 Enoplocotyle hawaiietisis n. sp., 56 Enoplocotylinae Tagliani, 1912, 56 Erpocotyle sphymae (MacCallum, 1931), 191 Gastrocotyla acanthocybii Meserve, 1938, x

75 Gastrocotyle trachwri v. Beneden et Hesse, 1863, 172 Gastrocotylidae Price, 1943,172 Gastrocotylinae Sproston, 1946, 172 Gempylitrema n. g., 127 Gempylitrema gempylli (Dillon et Hargis, 1965) n. comb., 127 Gempylitrema longipedunculatum n. g., n. sp., 125 Gempylitrematinae n. subf., 1 2 5 , 1 2 7 Haliotrema acanthuri n. sp., 64 Haliotrema amanses n. sp., 65 Haliotrema angulare n. sp., 66 Haliotrema angulocirrus n. sp., 66 Haliotrema annulocirrus n. sp., 67 Haliotrema bifurcocirrtis n. sp., 68 Haliotrema bisegmentatum n. sp., 69 Haliotrema bodiani n. sp., 70 Haliotrema brotulae n. sp., 71 Haliotrema caesiopercae n. sp., 72 Haliotrema canescens n. sp., 72 Haliotrema centropygis n. sp., 73 Haliotrema chelicirrus n. sp., 74 Haliotrema chromidis n. sp., 75 Haliotrema ctenochaeti n. sp., 76 Haliotrema curvicirrus n. sp., 76 Haliotrema epinepheli n. sp., 77 Haliotrema flagellatum n. sp., 78 Haliotrema flexicirrus n. sp., 79 Haliotrema lactoriae n. sp., 80 Haliotrema macracantha n. sp., 80 Haliotrema microphallus n. sp., 81 Haliotrema minutospirale n. sp., 82 Haliotrema pdmatum n. sp., 83 Haliotrema pervagoris n. sp., 84 Haliotrema priacanthi n. sp., 85 Haliotrema pterophallus n. sp., 86 Haliotrema rectangulare n. sp., 87 Haliotrema scyphovagina n. sp., 87 Haliotrema serpenticirrus n. sp., 88 Haliotrema sigmoidocirrus n. sp., 89 Haliotrema spiculare n. sp., 90 Haliotrema spirale n. sp., 91 Haliotrema tubulovagina n. sp., 92 Haliotrema zancli n. sp., 93 Heteraxininae Unnithan, 1957, 166 Heteraxinoides caprodontis n. sp., 166 Heterocotyle aetobatis Hargis, 1955, 59

Heterocotyle fhridana of Pearse, 1949, 59 Hexabothriidae Price, 1942, 190 Hexabothriinae Price, 1942, 190 Hexabothrium dasyatis n. sp., 190 Hexostoma keokeo n. sp., 141 Hexostoma sibi n. sp., 143 Hexostomatidae Price, 1936, 141 Kuhtiia scombri (Kuhn, 1829), 145 Lagenivaginopseudobenedenia etelis Yamaguti, 1966, 32 Lamellodiscus epsilon n. sp., 123 Lobatostoma albulae n. sp., 192 Mazocraeidae Price, 1936,145 Mazocraeinae Price, 1961,145 Metamicrocotyla mugilis n. sp., 184 Metamicrocotylinae Yamaguti, 1963, 184 Metopisthogyne sphyraenae Yamaguti, 1966, 136 Microbothriidae Price, 1936, 56 Microcotyloidea Unnithan, 1957, 152 Mierocotyle bothi n. sp., 178 Microcotyle emmelichthyops n. sp., 178 Miarocotyle polymixiae n. sp., 180 Microcotylidae Taschenberg, 1879, 178 Microcotylinae Monticelli, 1892,178 Monaxininae Unnithan, 1957, 165 Monocotylea Odhner, 1912, 19 Monocotylidae Taschenberg, 1879, 58 Monocotylinae Gamble, 1896, 58 Murraytrematoides kuhliae n. sp., 1 1 2 Nasicola n. g., 55 Nasicola klawei (Stunkard, 1962), 53 Nasobranchitrema pacificum Yamaguti, 1965, 1 1 4 Neohaliotrema maomao Yamaguti, 1965, 105 Neohexostoma kawakawa n. sp., 144 Neomicrocotyle carangis n. sp., 148 Neomicrocotyle indica (Unnithan, 1962) renamed N. unnithani n. sp., 150 Neomicrocotylinae Ramalingam, 1960,148 Neothoracocotyle acanthocybii (Meserve, 1938), 175 Nitzschiinae Johnston, 1931, 55 Oligoncobenedenia nasonis Yamaguti, 1965, 35 Opisthogyninae Unnithan, 1962, 132 Parahaliotrema Mizelle et Price, 1964, syn. of Haliotrema J. et T., 1922, 65 Parancyrocephaloides dactylopteri n. sp., 111 Polyopisthocotylea Odhner, 1912, 125

Index

Polystomatoidea Price, 1936, 190 Prostatomicrocotyla n. g., 187 Prostatomicrocotyla kuhliae n. g., n. sp, 185 Prostatomicrocotyla maomao n. sp., 186 Prostatomicrocotylinae n. subf., 185, 187 Protomicrocotyle celebesensis Yamaguti, 1953, 146 Protomicrocotylidae Price, 1936, 146 Protomicrocotylinae Johnston et Tiegs, 1922, 146 Pseudallobenedenia apharei Yamaguti, 1966, 29 Pseudallobenedenia opakapaka Yamaguti, 1966, 3! Pseudancyrocephdus n. g., 100 Pseudancyrocephdus duplicatus n. sp., 100 Pseudancyrocephdus kda n. g., n. sp., 98 Pseudancyrocephdus longicirrus n. sp., 101 Pseudancyrocephdus longispicularis n. sp., 102 Pseudancyrocephalus nasonis n. sp., 103 Pseudaxine decapteri n. sp., 172 Pseudempleurosoma carangis Yamaguti, 1965, 113 Pseudobenedenia elongata n. sp., 24 Pseudobenedenia merinthe n. sp., 25 Pseudobenedenia ovalis n. sp., 26 Pseudochauhanea sphyraenae Yamaguti, 1965, 174 Pseudodiclidophora decapteri Yamaguti, 1965, 127 Pseudodiclidophoridae Yamaguti, 1965, 127

287

Pseudodiclidophorinae Yamaguti, 1965, 127 Pseudodiscocojtyla opakapaka Yamaguti, 1965, 140 Pseudodiscocotylinae Yamaguti, 1965, 140 Pseudohdiotrematoides aurigae n. sp., 106 Pseudohdiotrematoides falcatus n. sp., 106 Pseudohdiotrematoides microphallus n. sp., 107 Pseudohdiotrematoides recurvatus n. sp., 108 Pseudohdiotrematoides triangulovagina n. sp., 109 Pseudohdiotrematoides zancli n. sp., 110 Pseudonitzschia uku Yamaguti, 1965, 55 Pseudopisthogytie lepidocybii Yamaguti, 1965, 132 Pseudopisthogynopsis lepidocybii Yamaguti, 1965, 137 Pseudopterinotrema albulae Yamaguti, 1966, 150 Pterinotrematidae Bychowsky et Nagibina, 1959, 150 Sibitrema poonui Yamaguti, 1966, 167 Sibitrematinae Yamaguti, 1966, 167 Tristoma adintegrum n. sp., 51 Tristoma adococcineum n. sp., 50 Vallisiinae Price, 1943, 139 Vdlisiopsis sphyraenae n. sp., 139