Monograph of the Neotropical Fern Genus Polybotrya (Dryopteridaceae) [34]

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\ Monograph of the Neotropical Fern Genus Polybotrya (Dryopteridaceae) RobbinC. Moran

Volume 34, Article November 1987

1

Monograph of the Neotropical Fern Genus

Polybotrya (Dryopteridaceae) RobbinC. Moran Illinois

Natural History Survey

Illinois

Department of Energy and Natural Resources

Department of Plant Biology University of Illinois

Illinois

at

Urbana-Champaign

Natural History Survey Bulletin

Volume 34. Article November 1987

1

This work

dedicated to

is

Dr. Robbin C.

parents, Livia

Ann Moran and John Howard Moran.

currently works at the Missouri Botanical Garden in St. Louis.

Natural History Survey, Lorin

Illinois

A

Moran

my

I.

Nevling, Chief

Division of the Illinois Department of Energy and Natural Resources

Printed by Authority of the State of Illinois

(62997—1,200—11-87)

No

charge

is

publications

made

is

for

available

most publications of the

Illinois Natural

ing them. Requests for multiple copies should be

made of Illinois

History Survey, and a

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are available to

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of those

anyone request-

writing and should explain the use to be

the publications. Address correspondence to the Office of the Chief at the address below.

Natural History Survey

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607 East Peabody Drive Champaign, Illinois 61820 Citation:

Moran, R.C. 1987. Monograph ofthe Neotropical Fern Genus /'o/)*o/r>'ecies

cells for

of Polybotrya ranges from 12

to 24,

with most species having between 14 and 18.

Both the epistomium and hypostomium consist

of Polybotrya as acrostichoid, but three types

coenosoric, and a

the species of

paraphysate

percent of the stalks from a single sample.

leaf.

Pteridologists previously described the sori

of

stalks, but

most conspicu-

ous aspect of dimorphy, but differences

on the stem,

have

In dried or rehydrated material, the apical

leaves oi Polybotrya resemble

a skeleton of the sterile ones because their

phy,

About three-fourths of

Polybotrya

of three or four thin-walled, transversely

elongated

cells.

All species of Polybotrya

have glabrous sporangial capsules, except P. imbcns. which has short, subulate hairs

at

the top of the capsule near the annulus (Fig.

30e,n. Usually two of these hairs occur on either

side

of the

annulus.

creating

the

impression that the capsule has "homs.""

Spores. Spore sizes, measured by the longest axis, are given

(when

available) at

the end of each species description.

Numbers

Monograph

November 1987

are for spwres

being placed

medium

is

measured immediately

after

water because

of

Poi.ybotra

ferns

(e.g.,

2S

Dryopieris and Poly stu hum).

this

Polybotrya spores are monolete, with the

readily available to taxonomists.

aperture linear and one-third to three-fourths

in distilled

Fifteen spores

were measured per specimen.

Spores of most Polybotrya species range

from 45-65 microns

with extremes

in length,

The

the length of the long axis.

aperture

is

often obscured by the broad [lerispore folds

and smaller spines. The exospore appears

of 32 and 80 microns. According to Tryon

smooth

and Tryon (1982). Polybotrya has relatively

genera of dryopteroid ferns. The perispore

large spores

compared

to those

of other gen-

era in their tribe Dryopteroideae. appyear dark

The spores

brown when viewed with

trans-

compound microscope deep orange when viewed with reflected

(Fig. 12), as

consists of

two

it

does

layers: the

spores of most

in

lower layer

is

thin

and appressed to the exospore; the upper layer is

thicker, with inflated folds

and echinate to

No constant differ-

mitted light under a

various degrees (Fig. 12).

but

ences were found between the three subgen-

light

under a dissecting microscope.

Spores of Polybotrya are within the genus

encountered

FiciURF.

1

1

sides of the

.

in

compared

fairly

era or smaller species groups.

The

uniform

to the variation

other genera of dryopteroid

appear

seriatis (note in

c.

a.

cell al the

peri-

P. allenuata: b. P. sorhifolia. showing both

P. espirilosanlensis; d. P. speciosa:

g the globose, glandular

between species

prominence and density of

sporal folds and spines. Typically, the in-

Sporangia of various Polybotrya species,

same sporangium;

principal differences

in the

c.

P.

osmundacea;

base of the paraphysis).

f,g.

P.fracli-

Illinois

Figure c.

12.

f.

bC.

Moran 3241 (CR). 26 (GH).

c

P.pinien.

scrralifolio.d. a. P. semipinnaki-.b. P. osmumtacea-.c. P. speciosa. a: Duane et al. i. P. cylindrica: P. h. crassirhizoma: P. P. alfredii: g. la Sola 251 (US), e: Schiinkc .?S0 (GH). c: Femller 261 (GH). d: Lellingcr & de

Spovcs oU\>tyhotrva.

P. gomezii:

6W->-' (F)

Natural History Survey

f:

M,mw

3I6S (CR).

and h arc x 5(XK1,

all

g;

Plowman

others are

x

1(XX).

et al.

4025 (GH).

h:

Handro 222S (GH).

i:

Webh

—

.

Monograph

November 1987

developed and the spines numerous that they impart a "fuzzy" appearance. However, the folds may be rela-

Polybotra

of

27

flated folds are well

P. altescandens , P. polyhotryoides, and P.

are so

serratlfolia (Fig. 13).

and P. sor-

tively low. as in P. goyazensis hifolia. or the spines

and/or density, as

Species

may

range

clearly

is

species bifolia

height

in

P. speciosa (Fig. I2i).

also differ in spore size. This

shown by

the

two

terrestrial

subgenus Sorbifoliu: P. sor-

the

in

may be reduced

in

and P. fractiserialis differ greatly

spore size

(40-47 and 52-56 microns

in

long,

Each of the four counts

had a chromosome number of h

=

4

i

a find-

.

ing that argues, along with morphological

among

features, for classifying Polyhotrya

dryopteroid

the

n

ferns,

= 4\. Chromosome

of which have

all

counts are

still

needed

from the other species of Polyhotrya. espe-

where polyploidy may be involved

cially

the evolution of

in

one species from another,

as in P. fractiserialis

and P. sorhifolia.

respectively), a difference that probably reflects different

ploidy levels.

Comparison of the spores shown

Figure

in

12 with the spores of other dryopteroid ferns

by Tryon and Tryon (1982) shows the spores of Polyhotrya are most like

Cladistic Analysis of the Species

A

cladogram of species relationships was

illustrated

constructed using the

that

sion 2.3 (Swofford

those of

Maxonia and Stigmaiopteris (Tryon

and Tryon include Cyclodium

Cyclodium. which

leris).

lated to Polyhotrya,

is

in

Stigmatnp-

most closely

re-

has spores similar to

ronym

PAUP program, verPAUP is an ac-

1985;

Using Par-

for Phylogenetic Analysis

simony). Table 5 shows the input data used in the analysis,

and Table 6 gives the charac-

and character

ters

used

states

in the input

data

those of Polyhotrya but less spiny (A.R.

matrix.

Smith 1986). This observation supports evi-

pothesized evolutionary pathways) for the

dence from external morphology that these

characters (Table 6) are

genera form a closely related group.

Further information on the characters and jus-

Chromosome Numbers

pathways

The

The only previous reports of chromosome numbers in Polyhotrya came from two sepacounts of P. osmundacea. one from

rate

Jamaica and the other from Trinidad; both gave a chromosome number of n = 41

(Walker 1966; Smith

&

Mickel 1977). To

in

Figure 14.

Morphology and in

the data set,

found a large number of equally par-

simonious cladograms. Therefore, a consen-

was printed

sus cladogram (Fig. 15)

50

first

trees to

terns they all

species

collected meiotic

in the

Because of homoplasy

PAUP

numbers

I

given

is

agreed on

the genus.

shown

(hy-

trees

section.

add to the information about chromosome in

state

of their postulated evolutionary

tification

Anatomy

character

had

the

for the

determine the branching patin

common. The 50

trees

branching patterns for

— about one-third of

the genus.

12

The

material during fieldwork in Latin America.

groups that had congruent branching patterns

Young

fertile

were subgenera Soromanes and

hours

in

segments were placed for 3-5 water

distilled

paradichlorobenzene.

saturated

with

The segments were

— group of species caudata — puhens).

(Fig. 15, .serratlfolia

the

then removed, blotted gently, and placed in

(Fig.

a fixative of 3;

the

acid. until

The it

1

ethyl alcohol to glacial acetic

material

was stored

in a

freezer

could be examined. Sporangia were

squashed

in a

drop of aceto-carmine and then

photographed This work

number counts

related to P. caudata

15,

remaining

numerous, grams.

new chromosome

for four species

P. alfredii.

equally

shown on

Homoplasy

accounted

species

Nevertheless,

species are

gram, a recorded

.Sorhifolia

espiritosantcnsis) and

parsimonious distinct

for

in

the

clado-

groups

of

the consensus clado-

result that supports the

subdivision of the genus.

following

28

Ii.i-iNOis

Naiurai. History Survey

Vol. 34. An.

1

"f

Figure

13.

Chromosome squashes of

interpretations are at the right,

a.

polyhotry aides, Costa Rica, Cartago.

3709 (MO);

d. P. alfredii,

four sfwcies of Polybotrya. All squashes have n

P. altescimdem. Ecuador. Pichincha.

Moran 2I7S (MO);

c.

Moron

= 4l. My

.^559 [CV\): b. P.

P. serralijhlia, Venezuela. Trujillo.

Costa Rica. Cartago. Moran 2442 (CR).

Moran

Monograph

November 1987

Table

5.

= unknown

29

Polybotra

Data matrix for cladistic analysis of 35 species of Polybotrya. Sec text for discussion of

character states and polaiily. Ancestor ?

of

character state.

=

NA = not

hypothetica! ancestor possessing

applicable

all

primitive character states.

.

.

Illinois

30

.

Nai ural History Survey

Tabi F. 6. Characters and character The numbers given to each character

states

used

Vol. 34, An.

in the cladistic analysis

of 35 species of Polyhotrya.

correspond with those shown on one of the cladograms

state

in

Figure 14.

= 4-pinnate;

Dissection of sterile leaves (Fig. 14a).

1

pinnate-pinnatifid; 4 2.

Venation (Fig. 14b).

3.

Type of

=

2-pinnate; 5

=

= close and

long-parallel;

fertile leaf (Fig.

botryoid; 3

14c).

= coenosoric; 4 =

=

1

1

=

1

3-pinnate-pinnatifid; 2

=

3-pinnate; 3

= 2-

-pinnate.

=

1

obliquely ascending: 2

= anastomosing.

botryoid, but with lamina not completely reduced; 2

= fully

caudate.

4.

Pinnule arrangement (Fig. 14d).

5.

Symmetry of pinnule base

0=

anadromic;

=catadromic.

1

= symmetrical and

(Fig. 14b).

truncate;

1

= prolonged

acroscopically

and truncate; 2 = symmetrical and cuneate. 6.

Submarginal connecting strand (Fig. 14e).

7.

Stem

scale base (Fig.

= absent;

14d).0= attached by a single O=

=

8.

Hair type (Fig. 14b).

9.

Pubescence of laminar surface (Fig. 14b). O

long, acicular;

1

1

point;

= several =

1

small, jointed;

=

connections; 2

= present.

attached across the width of the base.

2=

uncinate.

both surfaces pubescent;

= glabrous;

1

2

=

abaxial

surface pubescent. 10. 1

1.

= glabrous;

Pubescence of laminar margin (Fig. I4d).

0=

Pubescence of costae (Fig. 14b).

Lamina base

13.

Scale color (Fig. I4f).

=ciliate.

uniform and dense pubescence;

1

= moderately

pubescent

= glabrous.

or with scattered hairs; 2 12.

1

= deltate;

(Fig. I4b).

=

1

=

= cuneate.

reduced; 2

golden or yellow;

1

= brown;

2

=

reddish or bnghl castaneous; 3

= cream

or whitish. 14.

Receptacular hairs (Fig. 14d).

15.

Size of lamina (Fig. 14d).

16.

Costal scale type (Fig.

0= >

140-

and tortuous; 3

= caducous.

17.

Apex of

leaf (Fig. !4d).

18.

Stem

19.

Shape of the

20.

Spore size (Fig. I4d).

.sterile

habit (Fig. I4d).

=

=

=

1

meter;

1

=