DEAMIS M. DEVAA Studies on Ophiocomid

v Brittlestars. I. A New

^m Genus (Clarkcoma) of

W Ophiocominae with a *

Reevaluation of the

Genus Ophiocoma

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SMITHSONIAN CONTRIBUTIONS TO

ZOOLOGY

NUMBER 51

Dennis M. Devaney Studie s Oil

Brittlestars. I. A New

Genus (Clarkcoma) of

Ophiocominae with a

Reevaluation of the

Genus Ophiocoma

SMITHSONIAN INSTITUTION PRESS

CITY OF WASHINGTON

I97O
ABSTRACT

Devaney, Dennis M. Studies on Ophiocomid Brittlestars. I. A New Genus (Clarkcoma) of Ophiocominae with a Reevaluation of the Genus Ophiocoma. Smithsonian

Contributions to Zoology, 51:1-41, 1970.—Internal as well as external skeletal features

support the decision to divide the shallow water tropical genus Ophiocoma into species

groups. Differences in embryological and larval morphology also suggest partition of

the genus. Two species formerly in Ophiocoma are now placed in the new genus Clarkcoma (type-species, Ophiocoma canaliculata Liitken). The relationship of the oral

papillae and buccal tentacle scale, sequence of arm spines, and nature of oral and

dental plates have been analyzed in order to reach conclusions regarding the taxonomic

position of the taxa. These characters also suggest intergeneric relations within the

subfamily. Descriptions and keys are given for the two genera as well as for the intrageneric groups and species of Ophiocoma; also, the specific limits of many species are

reviewed.

Contribution No. 349, Hawaii Institute of Marine Biology, University of Hawaii

Official publication date is hand stamped in a limited number of initial copies and is recorded

in the Institution's annual report, Smithsonian Year.

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Dennis M. Devaney Studies Oil

Brittlestars. I. A New

Genus (Clarkcoma) of

Ophiocominae with a

Reevaluation of the

Genus Ophiocoma

Stimulated in part by H. L. Clark's (1921) revision

of the Ophiocominae and by Murakami's (1963) report on the oral and dental plates of ophiuroids, recent

examination of many species of ophiocomid brittlestars has made it possible to reach some substantial

conclusions regarding the relationships among this

largest subfamily of Ophiocomidae in the order Chilophiurida (Matsumoto, 1917). Of particular interest

has been the genus Ophiocoma, whose species not only

show affinity with other genera in the subfamily but

indicate a polyphyletic assemblage of related taxa. At

the same time, conventional external characters have

been found inadequate to define the genus, and careful examination of internal skeletal plates has necessitated the removal of two species (bollonsi and canaliculata) from Ophiocoma and the formation of four

separate groups.

This study has resulted to a large extent from research on the systematics and postlarval growth

changes of ophiocomid brittlestars.1 Part of the work

was completed while the author held a visiting postdoctoral research associateship through the National

Research Council at the Smithsonian Institution in

1968—1969. Essential to this study has been the availability of the collections at the United States National

1

 In partial fulfillment of requirements for the PhD degree,

Department of Zoology, University of Hawaii, 1968.

Dennis M. Devaney, Bernice P. Bishop Museum, P.O. Box

6037, Honolulu, Hawaii 96818.

Museum (USNM) which contain specimens collected

by the Albatross and other important specimens. I

thank Dr. David L. Pawson and Miss Maureen

Downey in the Division of Echinoderms at the Smithsonian Institution for their encouragement during this

project. My sincere appreciation is also extended to

Dr. H. B. Fell at the Museum of Comparative Zoology

(MCZ), Captain Fred Ziesenhenne at the Allan Hancock Foundation (AHF), Dr. H.-E. Gruner at the

Zoologisches Museum Berlin (ZMB), and Miss Ailsa

M. Clark at the British Museum (Natural History)

for making collections at their institutions available or

for contributing valuable suggestions during this study.

I am deeply grateful to Dr. Roland W. Force, director

of the Bernice P. Bishop Museum (BPBM), Honolulu,

for permitting me to participate in the 1967 Smithsonian-Bishop Museum-National Geographic Mollusk

Expedition to southeastern Polynesia, from which

specimens essential to this work were collected and

now are deposited in the Bishop Museum.

This publication is the first in an anticipated series

of reports dealing with the species and genera of the

Ophiocomidae.

Clarkcoma, new genus

TYPE-SPECIES.—Ophiocoma canaliculata Liitken,

1869.

DIAGNOSIS.—Ophiocominae with thin, compressed,

minutely serrated arm spines; five to eight arm spines

1
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

along each side of arm segments just beyond disc edge

and fewer distally; second or third spine in row longest (Figure 9). Disc granules low, rounded and evenly

distributed over aboral surface; ambital granules sometimes slightly larger or more elongate; granules absent

or reduced and scales exposed interradially near oral

shields and genital slits. Oral plates (jaws) with abradial muscle area auriculate, having a deep central

region with median ridge and short branching processes

(Figure 4) ; adradial muscle area less than one-third

total length of plate and confined to lower (oral) portion (Figure 5). Adoral shields with proximal edges

well in front of oral shield and nearly or actually meeting (Figures 1,2). Four or five oral papillae along each

jaw margin; outer papilla broadest, but one or more

small granules usually present between outer papilla

and buccal tentacle scale; buccal tentacle scale separated from outer oral papilla and not abutting against

adoral shield (Figures 1, 2); an integumentary area

separates these two ossicles. Upper (aboral) arm plates

rhomboidal, with narrowly tapering lateral borders;

less than one-half of maximum breadth contiguous

with adjacent plates along distal and proximal edges

(Figures 10, 11). Lower (oral) arm plates approximately two times broader than long (Figures 12, 13).

Dental plate from 1.9 to 3.2 times longer than broad;

septum of upper tooth foramen equal to or narrower

than lower septum (Figures 8,14).

REMARKS.—When H. L. Clark (1921) reviewed the

genus Ophiocoma he was unable to relate either O.

bollonsi or O. canaliculata within his species-group

framework. Discussing canaliculata he stated (p. 128) :

"The species is a very distinct one, quite different from

any other member of the genus, particularly in the

form of the arm-spines and the large adoral plates."

He noted that bollonsi (known at the time only from

the type-specimen) was "apparently most nearly related to canaliculata, with which species it has several

important characters in common, notably the large

adoral plates" (Clark, 1921, p. 132). Several characters of each species in new material at hand indicate

the necessity to remove these species from Ophiocoma

and place them in a new genusV Clarkcoma.

The following features characterize Clarkcoma, new

genus, and serve to separate it from Ophiocoma: (1)

The arm spines are quite thin and compressed, in contrast to the more rounded, thicker spines of Ophiocoma

(with the exception of O. pusilla) ; (2) the adoral

shields converge in front of the oral shield and often

come in contact (Figures 1, 2), whereas in Ophiocoma

FIGURE 1.—Clarkcoma canaliculata; oral mouth sectors (d.d. 15 mm) : a, buccal tentacle scale;

b, outer oral papilla; c, accessory oral papillae; d, ventral shield; e, adoral shield; /, oral shield.
NUMBER 51

FIGURE 2.—Clarkcoma canaliculata; oral mouth sectors (d.d. 20 mm). (Abbreviations as in

Figure 1.)

the adorals are confined to the sides of the oral shield

(Figure 3); (3) the buccal tentacle scale is small,

vertically directed, and separated from the adoral

shield, and one or more small rounded granular papillae intrude between the broad outer oral papilla and

the buccal tentacle scale (Figures 1, 2), whereas in

Ophiocoma the buccal tentacle scale is relatively large,

more horizontally directed, adjacent to the outer oral

papilla, in contact with the adoral shield, and no small

papillae occur between the outer oral papilla and

buccal tentacle scale (Figure 3) ; (4) the oral plate

shows an abradial muscle surface with a deep convexity, a narrow median ridge, and several short processes (Figure 4) ; the adradial muscle is restricted to

only a small part of the adradial side of the plate

(Figure 5). In Ophiocoma however, the abradial

muscle surface is broken into a series of shallow somewhat parallel ridges and grooves (except O. pusilla)

and the adradial muscle surface extends the whole

length of the plate (Figure 44).

Both species of Clarkcoma are limited to southern

temperate waters, whereas species of Ophiocoma, as

now restricted, appear in tropical and subtropical

waters. The two genera have been reported together

only at one Western Australian locality (Rottnest

Island, where Ophiocoma occidentalis and Clarkcoma

canaliculata were collected (H. L. Clark, 1938, 1946).

The new genus is named in honor of Hubert Lyman

Clark, Austin H. Clark, and Ailsa M. Clark, all of

FIGURE 3.—Ophiocoma erinaceus; oral mouth sector (d.d.

11 mm), oral shield aberrantly split. (Abbreviations as in

Figure 1.)

whom have made many significant contributions in

echinoderm systematics.

RELATIONSHIPS.—In the separation of the outer oral

papilla from the buccal tentacle scale, Clarkcoma approaches the more evident separation of these ossicles
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

found in Ophiocomina (Figure 6) and in Ophiopteris

(Figure 7) within the subfamily Ophiocominae. In all

three genera the buccal tentacle scale is not in contact

with the adoral shield, in contrast to the condition in

the other genera—Ophiocoma (Figure 3), Ophiomastix, Ophiarthrum, and Ophiocomella—in the subfamily. Likewise, Clarkcoma, Ophiocomina, and

Ophiopteris are similar in having the adoral shields

located along the interior angle of a broad oral shield

and usually meeting within. In this respect they also

differ from the four other genera in the subfamily.

FIGURE 4.—Clarkcoma bollonsi; abradial surface of oral plate.

g, Abradial muscle, scar.

FIGURE 5.—Clarkcoma bollonsi; adradial surface of oral plate.

h, Adradial muscle scar.

FIGURE 6.—Ophiocomina nigra; oral mouth sectors (d.d. 10 mm). (Abbreviations as in Figure 1.)
NUMBER 5 1

FIGURE 7.—Ophiopteris papillosa, oral mouth sectors (d.d.

12 mm). (Abbreviations as in Figure 1.)

In the nature of the thin, compressed arm spines

Clarkcoma also shows greater similarity to Ophiopteris

and to Ophiocomina than to the other genera.

Clarkcoma, however, is easily distinguished from

Ophiocomina and Ophiopteris by the presence of

hylinated tips of the teeth, a character which it shares

with the other genera of Ophiocominae. Clarkcoma

has well-developed teeth foramina in the dental plate

(Figure 8), whereas these are reduced in Ophiopteris

and absent in Ophiocomina. The jaw plate of Ophiocomina has a smooth and relatively smaller abradial

muscle surface, unlike the condition noted for Clarkcoma. The adradial muscle surface of the jaw plate,

however, is approximately the same size and shape in

Clarkcoma, Ophiocomina, and Ophiopteris, being

short and restricted to the oral portion of the plate,

whereas in other genera of Ophiocominae it is elongate and often crosses most of the plate.

Clarkcoma, Ophiocomina, and Ophiopteris each

has two species restricted to temperate waters, in contrast to the more tropical distribution of the other

Ophiocominae genera.

Clarkcoma appears to be more closely related to the

Ophiocomina-0phiopteris branch of the Ophiocominae than to other genera in the subfamily.

SPECIES EVALUATION. Clarkcoma bollonsi is known

from temperate waters around New Zealand, while

C. canaliculata has been reported from temperate

waters of Australia. The species show many similarities,

and in the following evaluation the two taxa are considered together for purposes of comparison.

FIGURE 8.—Clarkcoma canaliculata; proximal surface of dental plates (d.d. 18 mm), i, Dental papillae area.

Clarkcoma bollonsi (Farquhar)

Ophiocoma bollonsi Farquhar, 1908, p. 108.—H. L. Clark,

1921, p. 132.—Koehler, 1922, p. 314.—Mortensen, 1924,

p. 120, fig. 9; 1936, p. 260.—Fell, 1949a, p. 123, fig. 10;

1952, p. 24; 1958, pp. 2, 29; 1962, pp. 58 (fig. b), 59.—

Hurley, 1959, pp. 144-145, figs. 2-4.—Graham, 1962,

p. 200.—Pawson, 1965, p. 255.—McKnight, 1967, pp. 305-

306.

MATERIAL EXAMINED.—New Zealand: Cook Strait,

BPBM, no number (4) ; Foveaux Strait, USNM

E10,137 (2) ; no definite locality, BPBM W1611 (1).

DIAGNOSIS.—See under Clarkcoma canaliculata

(Liitken).

Clarkcoma canaliculata (Liitken)

Ophiocoma canaliculata Liitken, 1869, p. 46; Lyman, 1882,

pp. 168, 177; Koehler, 1904, p. 75, figs. 30-32; 1922,

p. 314; H. L. Clark, 1921, pp. 123, 128; 1928, p. 437, figs.

130a,b; 1938, p. 332; 1946, p. 244j A. M. Clark, 1966,

pp. 291, 294, 327.

Ophiocoma canaliculata var. pulchra H. L. Clark, 1928,

p. 439, figs. 131a,b.

Ophiocoma punctata Koehler, 1931, p. 205, pi. 14, figs. 2-5.

Ophiocoma pulchra H. L. Clark, 1938, p. 333; 1946, p. 244.—

Dakin, Bennett, and Pope, 1960, p. 324, pi. 85 (bottom).—

A. M. Clark, 1966, pp. 291, 327.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 9.—Clarkcoma canaliculata; proximal view of arm segment and spines (segment 15).

DIAGNOSIS (for Clarkcoma bollonsi and C. canaliculata) .—Disc diameter (d.d.) of both species to 24 mm;

arms between three and four times as long as disc diameter. Granules in both species covering aboral surface

of disc and extending into oral interradial area to variable extent. Specimens of C. canaliculata from New

South Wales having more extensive granulation interradially than those from South and Western Australia.

Aboral surface of longest arm spines of both species

often showing evidence of a slight central depression

("canaliculate") ; more evident for specimens of C.

canaliculata examined. Longest spines frequently widened at tip (Figure 11). Mortensen (1924, p. 121)

noted the outer part of a few of the arm spines in C.

bollonsi was swollen. He suggested that a "parasitic

organism" might be the cause of this condition, and in

sectioning these spines, he found a "peculiar radiating

structure." No evidence of a foreign organism could

be detected, however, but Fell (1952, p. 24) noted

"the presence of three kinds of spines on otherwise similar material" and concluded that "this would confirm

Mortensen's opinion that club-shaped spines are

pathological."

Sequence of spines on each side of first ten proximal

arm segments for an 11-mm (d.d.) specimen of C. bollonsi: 3-4-4(or 5)-5-6-6(or 7)-6(or 7)-6-6-5(or 6);

number of spines decreasing distally, with four and five

spines beyond 25th segment. Farther out on the arm,

four, and finally three spines.

Three specimens of C. canaliculata (d.d. 7-18 mm)

with following spine sequence: each side of first four

proximal segments with 3-3(or 4)-3(or 4)-4(or 5)

spines; beyond segment 3, an increase in number

of spines on each segment with increasing size of speciFIGURE 10.—Clarkcoma bollonsi; upper and part of lateral

arm plates with arm spines removed (d.d. 20 mm).

MATERIAL EXAMINED.—New South Wales: Newport,

MCZ 6726 (1); Port Jackson, MCZ 5905 (paratype,

Ophiocoma punctate Koehler); USNM 38638 (1);

Shell Harbor, MCZ 5237 (1). South Australia: St.

Vincent Gulf, MCZ 3462 (3), 5905 (1); Spencer

Gulf, MCZ 4664 (2 paratypes, Ophiocoma pulchra

H. L. Clark). Western Australia: Bunkers Bay, MCZ

5218 (2) ; Cape Naturaliste, BPBM, no number (5);

Cheyne Beach, BPBM, no number (2).
NUMBER 5 1

men determined by comparing spine sequence of small

and large specimens (see Table 1).

An evident specific difference between C. bollonsi

and C. canaliculata appears in the shape of the dental

plates, and this is reflected externally by the extent of

the dental papillae. In C. bollonsi a greater proportion

of the plate is occupied by dental papillae tubercles,

and the overall length to breadth ratio of the plate is

greater than for C. canaliculata (compare Figure 8,

FIGURE 11.—Clarkcoma canaliculata; aboral side of disc,

upper arm plates and arm spines (d.d. 20 mm).

TABLE 1.—Number of arm spines on arm segments of

Clarkcoma canaliculata

m*c

diameter

Number

of spinet

Segment!

7 mm

18 mm

7 mm

18 mm

7 mm

18 mm

7 mm

18 nun

6

6

7

7

5

5

3

3

segment 6

segments 5-15

none

segments 6-10

out to segment 12

out to segment 35

segments 21 to end

segments 47 to end

14). This difference appears in similar-sized specimens

of each species.

Clarkcoma bollonsi has dental papillae arranged

regularly in several transverse rows, their number

reduced toward the teeth; papillae in the lateral columns are larger than those of center. Clarkcoma

canaliculata has papillae occurring in nearly the same

FIGURE 12.—Clarkcoma bollonsi; lower arm plates and tentacle scales, some removed or broken (d.d. 20 mm.)

FIGURE 13.—Clarkcoma canaliculata; lower arm plates and

tentacle scales, including segment 15 (d.d. 24 mm).
8 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

number above and below (near teeth); irregularly

placed in three or four columns; relatively larger and

less extensive than for bollonsi of similar size. Number

of papillae varying according to size of specimens. C.

bollonsi with dental papillae area slightly wider than

area occupied by teeth (Figure 14) ; length-to-breadth

ratio of plate, 2.9-3.1 : 1. For C. canaliculata dental

papillae area about same width as tooth area (Figure

8 ); length-to-breadth ratio, 2.0-2.7 : 1.

FIOURE 14.—Clarkcoma bollonsi; proximal surface of dental

plate (d.d. 20 mm).

There is greater evidence of the canaliculate shape

of the upper surface of the longer arm spines in C.

canaliculata than in C. bollonsi, but the presence of

these spines on C. bollonsi makes the character difficult

to use as a means for species differentiation.

In his key to the species of Ophiocoma, H. L. Clark

(1921, p. 123) distinguished canaliculata and bollonsi

by differences in disc granules: those of bollonsi "at

least near the disc-margin, higher than thick, becoming

more or less markedly spiniform"; those of canaliculata

"nearly or quite spherical and of more or less uniform

size." The spiniform nature of the granules at the disc

margin as originally reported by Farquhar (1908) for

the type of bollonsi has not been apparent, however, in

the specimens I have examined. In these specimens the

marginal disc granules do not appear to differ from

those on either the oral or aboral surface of the disc.

It must be assumed that there is a certain amount of

individual variation in this character and that such

variation does not reflect a constant specific distinction

between the two species.

FIABITAT AND DISTRIBUTION.—Clarkcoma bollonsi

was first taken from a depth of 16 meters in Cook

Strait, New Zealand (Farquhar, 1908). Mortensen

(1924) recorded specimens collected from a "hard

bottom" in depths ranging from 5 to 120 fathoms at

several New Zealand localities and, later (1936), a

single specimen from 128 meters in Cook Strait. Hurley (1959) gave an interesting report on the habitat

and apparent density of C. bollonsi through the use of

underwater photography. He noted the ophiuroids occurring in gregarious masses, and related this to their

manner of feeding, suggesting that this species formed

part of "a typical filter or detritus feeding community

in an outer sublittoral cobble bottom where there is

considerable seafloor current" (Hurley, 1959, p. 145).

Fell (1958) reported this species from a number of

New Zealand stations ranging in depth from 3 to 350

fathoms. Pawson (1965) reported specimens from the

holdfasts of the algae Lessonia and Durvillea apparently collected intertidally at the Snares Islands. McKnight (1967) listed C. bollonsi from the Chatham

Rise off eastern New Zealand collected in 210 meters.

Clarkcoma bollonsi, therefore, apparently is restricted to waters along the coast of New Zealand and

on the Chatham Rise. The southern limit of this species

appears to be the Snares Islands at latitude 48° South

(Pawson, 1965).

Dakin, Bennett, and Pope (1960, p. 324) mention

the occurence of C. canaliculata (as Ophiocoma pulchra) from Australian low water level on rocky coasts,

"especially where there are rockpools and large stones

resting upon pockets of sand or gravel. The ophiuroids

lie under the stones and keep strictly in the shade under

such conditions." Koehler (1931) obtained his specimens (as Ophiocoma punctata) in depths of 5 to 8
NUMBER 51

meters off Port Jackson, Australia, and A. M. Clark

(1966) reported specimens (as Ophiocoma canaliculata) from two stations at depths of 1.5 and 4.5 fathoms

at Port Phillip, Victoria.

Clarkcoma canaliculata is known from temperate

Australian waters. Its range extends from the vicinity

of Shell Harbor, New South Wales (lat. 34° S), along

the South Australian coast to Rottnest Island, Western Australia (lat. 33° S) ; it has not yet been reported

from Tasmania.

DISCUSSION.—H. L. Clark (1928) -considered

Ophiocoma canaliculata to have two color forms, and

he designated one form by the variety name pulchra.

The basic difference was in pigmentation of the arm

spines and oral arm plates. In 1931 Koehler described

a species from Port Jackson, New South Wales, under

the name Ophiocoma punctata. Although resembling

O. canaliculata quite closely, Koehler listed several

characters which he regarded as sufficient to distinguish the two species. These included the form of the

upper arm plates, less-pronounced grooves on the

spines, a difference in the shape of the oral shields,

disc-granule size, and pigmentation (Figure 15). H. L.

Clark (1938) regarded Koehler's species to be identical with O. canaliculata var. pulchra, and considered

pulchra a distinct species because no intermediate

specimens of O. canaliculata and O. pulchra had been

seen. He noted, however, that the distributional range

of the two species coincided and their morphological

features were remarkably similar. Later, a similar diagFIGURE 15.—Clarkcoma canaliculata (MCZ 5237, labeled

"Ophiocoma pulchra, Shell Harbor, Australia"); upper side

of arm.

nosis was made, and he noted that "the actual relationship of the two forms still is an open question"

(H.L.Clark, 1946, p. 245).

Two of H. L. Clark's paratypes labeled Ophiocoma

pulchra (MCZ 4664) and one of Koehler's paratypes

described as O. punctata (MCZ 5901) have been examined. Comparison with specimens identified as O.

canaliculata reveals several of the differences mentioned by Koehler (1931) which distinguished punctata from canaliculata, basically in the pigmentation.

I am not convinced, however, that the differences are

specific; they may only reflect variation in a single

species. Until more specimens are available for comparison, Ophiocoma pulchra is considered conspecific

with Clarkcoma canaliculata.

Genus Ophiocoma Agassiz

Ophiocoma Agassiz, 1836, p. 192.—Miiller and Troschel,

1842, p. 98.—Liitken, 1869, p. 94.—Lyman, 1882, pp.

167-168.—H. L. Clark, 1921, pp. 120-121.

TYPE-SPECIES.—Ophiura echinata Lamarck, 1816

(see H. L. Clark, 1915, p. 290).

DIAGNOSIS.—Ophiocominae with three to seven

solid (except O. pusilla), generally smooth arm spines.

Disc with granules, uniform or variable in size and

shape, sometimes extending into oral interradial region.

Oral plates (jaws) with well-developed abradial muscle surface having a series of indentations or shallow

ridges and grooves (except O. pusilla). Adoral shields

confined to sides of oral shield and not meeting in

front of oral shield. Oral papillae, 3, 4, rarely 5, contiguous; outer usually widest. Buccal tentacle scale

in contact with both ventral and adoral shields.

REMARKS.—Louis Agassiz (1836) first proposed the

generic name Ophiocoma for a large number of species

described by Lamarck in 1816. Agassiz simply included

all the species in Lamarck's genus Ophiura which had

been designated and listed as section B by Blainville

(1834, p. 244) for that group of species characterized

by long arm spines that were not appressed against the

arm segments. As Loriol (1894, p. 25) pointed out,

this brief diagnosis was applicable to many species

which subsequently became separated into several other

genera.

Only three species considered by Agassiz as Ophiocoma belong to this genus under its present definition,

and two of these, O. squamata and O. echinata, were

nominally designated by Agassiz in his original work.
10

A third Lamarckian species, scolopendrina, was included along with the other species merely by "etc."

H. L. Clark (1915, p. 290) designated the type-species

of the genus correctly as Ophiura echinata, even

though Lyman (1865, p. 70) had erroneously designated O. scolopendrina Agassiz.

Miiller and Troschel (1842) focused attention on

fundamental characters by which the genus could be

more accurately defined. They indicated the importance of both oral and dental papillae (which were

to become the key family characters) as well as the

granulation of the disc. Greater elaboration of the

generic characters was presented by Lyman (1882),

but his intrageneric characters (internal disc scaling

and nature of the radial shields) have not lead to

definitive conclusions regarding species interrelationships.

Liitken (1869) first pointed out that certain species

of Ophiocoma shared characters that linked them more

closely to each other than to other species in the genus.

The possible relationships of the species were discussed

in more comprehensive terms by H. L. Clark (1921)

who noted that differences in disc granulation, number

of tentacle scales, pigmentation, and limits of geographic distribution could be used to divide the genus

into three groups—designated BREVIPES, PUMILA, and

SCOLOPENDRINA after nominal species in each group.

All but four of the species of Ophiocoma recognized

by Clark were placed in these groups. Two of the four

not grouped by Clark (bollonsi and canaliculata) have

been removed and form the new genus Clarkcoma,

while the other two {pica and pusilla), together with

O. longispina, form a separate group in the genus

Ophiocoma.

Through the work of Grave (1898) and Mortensen

(1921, 1931, 1937) we know that three species of

Ophiocoma in the SCOLOPENDRINA group (echinata,

erinaceus, and scolopendrina) have a unique "thorny"

fertilization membrane as well as larvae with very similar skeletons. In contrast, Mortensen (1937) found

Ophiocoma pica to have a smooth fertilization membrane and a markedly different larval skeleton.

Recently Ophiocoma pumila, collected in British Honduras (7 March 1969), was fertilized, and stages in

its larval development were followed. In contrast to

members of the SCOLOPENDRINA group, but similar to

O. pica, the fertilization membrane of pumila is smooth,

yet the skeleton shows the well-developed body rods

with transverse and end rods in contact (Figure 16).

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

In this respect the larval skeleton is more like that

found in the SCOLOPENDRINA group. Thus, although

the evidence is not complete, there are differences in

embryological and larval characters between several

species of Ophiocoma, which, on the basis of adult

characters, are considered in separate groups. Extension of this study may further show that premetamorphosis stages provide morphological characters that

support the separation of the species in these and other

ophiuroid taxa.

FIGURE 16.—Ophiocoma pumila; 13-day-old larva.

RELATIONSHIPS.—H. L. Clark (1921) briefly discussed the relationships of other genera in the subfamily to Ophiocoma. Although distinguishing Ophiomastix from Ophiocoma, he felt that the line separating

the two genera was not clear. For example, three

species of Ophiomastix (asperula, elegans, and mixta)

were considered to be difficult to separate from species

of Ophiocoma in the PUMILA group on the basis of the

disc granulation alone. Further, he recognized Ophiocoma pusilla, which was considered to have "clubshaped" arm spines, a primary diagnostic feature of

Ophiomastix, while other species of Ophiocoma also

shared this character with Ophiomastix even though

lacking distinct disc spinules. With the exception of

Liitken (1869, p. 95), Clark and others, however, failed

to note that species of Ophiomastix have an alternating

number of arm spines beyond the disc edge occurring

on opposite sides of the same segment or on adjacent

segments, in addition to having the upper spine usually

greatly enlarged or swollen (Figure 50). The important

consideration here is that the alternating sequence and

enlargement of the upper arm spines also are charac-
NUMBER 51 11

teristic of species in the SCOLOPENDRINA group of Ophiocoma (although these species do not have the arm

spines as strongly modified into "clubs" as do some of

the species in Ophiomastix).

The alternation and enlargement of the upper arm

spines is also evident in the genus Ophiarthrum, whose

three species H. L. Clark regarded simply as specialized

offshoots of Ophiocoma in which the disc granules

were lost. The relationship of Ophiomastix and Ophiarthrum to the SCOLOPENDINA group of Ophiocoma is

further indicated by the similarity in the shape of the

oral and dental plates.

The genus Ophiopteris, with two species showing an

interesting and puzzling discontinuous distribution on

opposite sides of the Pacific, was suggested by H. L.

Clark to have been derived independently from two

species of Ophiocoma (aethiops and erinaceus) in the

SCOLOPENDRINA group. There is no evidence, however,

to support this suggestion, and there are striking differences in the relationships of the oral papillae and

buccal tentacle scale as well as in characteristics of the

oral and dental plates between the two genera. Furthermore, the arm spines are of an entirely different

nature and do not alternate in Ophiopteris as in the

SCOLOPENDRINA group. In fact, there is no evidence

of Ophiopteris having evolved from any extant species

of Ophiocoma, and Ophiopteris shows closer morphological affinity to Ophiocomina and Clarkcoma as indicated earlier.

Another genus, Ophiocomella, made up of small,

primarily hexamerous species, had not been established at the time of Clark's 1921 review of the subfamily; however, one species, parva, considered (as

O. sexradia) in this genus was placed in the PUMILA

group of Ophiocoma. Arguments supporting the validity of Ophiocomella have been presented by A. H.

Clark (1939) and Ailsa M. Clark (in Parslow and

Clark, 1963). Further evidence (given in the present

paper) is based on differences in the arm spine sequence and oral (jaw) plate that indicate separation

of Ophiocomella from species in the PUMILA group of

Ophiocoma.

Ophiocomina, the sixth genus in the subfamily, was

considered by H. L. Clark (1915, 1921) to belong in

another family (Ophiacanthidae). Mortensen (1920)

and Koehler (1922) nonetheless gave strong evidence

to support the inclusion of Ophiocomina in the

Ophiocomidae. The very small and smooth surface of

the abradial muscle area of the oral plate and the lack

of hylinated teeth separate Ophiocomina from any

species of Ophiocoma; yet, these and other features

suggest closer affinity to Ophiopteris and Clarkcoma.

SPECIES EVALUATION.—By the time H. L. Clark

(1921) reviewed the genus Ophiocoma 32 specific

names had been assigned to it. Of these, Clark removed 22 names as synonyms in other genera. In addition, species correctly assigned to Ophiocoma which

are considered merely synonyms for other species in

the genus also were listed by Clark. Several corrections

(based on the present study) to this evaluation are as

follows:

(1) Ophiocoma dentata Miiller and Troschel, 1842,

is the senior synonym for O. insularia Lyman, 1861,

O. variegata Smith, 1876, and H. L. Clark's (1921)

two varieties of O. brevipes (dentata and doederleini).

(2) O. doederleini Loriol, 1899, is considered a valid

species.

(3) O. insularia var. longispina H. L. Clark, 1917,

is considered a valid species.

(4) O. tumida Miiller and Troschel is a junior synonym of Ophioderma longicauda (according to Koehler, 1924, p. 342).

(5) O. wendti Miiller and Troschel, 1842, is the

senior synonym for O. riisei Liitken, 1859.

(6) O. punctata Duchassaing, 1850, is a junior homonym for O. punctata Forbes, 1841, and apparently

is a synonym of O. pumila (according to Lyman, 1872,

p. 7) or O. brevipes (according to Koehler, 1907a,

p. 327).

Since 1915, several new species have been proposed,

and their taxonomic position in the genus Ophiocoma

is as follows:

(1) Ophiacantha macroplaca H. L. Clark, 1915,

is a valid species of Ophiocoma.

(2) Ophiocoma pulchra H. L. Clark, 1928, appears

to be merely a color form of O. canaliculata Liitken,

1869 (now considered in the genus Clarkcoma).

(3) Ophiocoma punctata Koehler, 1931, is a junior

primary homonym for O. punctata Forbes, 1841, and a

junior synonym for O. canaliculata Liitken, 1869.

(4) Ophiocoma delicata H. L. Clark, 1932, is a

species of Ophiarachna (family Ophiodermatidae).

(5) Ophiocoma anaglyptica Ely, 1944, is retained

as a valid species.

(6) Ophiocoma latilanxa Murakami, 1943, is considered a junior synonym for O. pusilla (Brock, 1888).

(7) Ophiocoma alternans Endean, 1963, is a junior

homonym for O. alternans Martens, 1870.
12 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Key to Species-Groups of Ophiocoma

1. Similar number of arm spines on each side of arm segments beyond disc; upper arm spines

not noticeably thickened 2

Alternating number of arm spines, usually 3 and 4 on each side of same or adjacent segments

beyond disc; upper arm spine thicker and often markedly longer than lower spines.

Scolopendrina group

2. Disc granules uniform in size, rarely elongate or spiniform; two tentacle scales on more than

first five proximal segments 3

Disc granules variable in size, some elongate or spiniform; one tentacle scale on all but the

first five proximal segments Pumila group

3. Upper arm plates with angular lateral margins and much broader along distal than proximal

border (Figure 27); disc granules not closely packed around oral shield Pica group

Upper arm plates with broadly rounded margins and not much broader along distal than

proximal border (Figure 17); disc granules closely packed up to oral shield.

Brevipes group

1. BREVIPES Group

Three species in the BREVIPES group of Ophiocoma

are recognized in this paper: O. brevipes Peters, 1851;

O. dentate Miiller and Troschel, 1842; and O. doederleini Loriol, 1899. All three species have Indo-Pacific

distribution, and have been found primarily in shallow

sublittoral waters, usually under boulders or attached

coral on a sand or sand-and-rubble substratum.

DIAGNOSIS.—Four to six arm spines on each side

of proximal arm segments beyond disc edge; upper

arm spine seldom equal to and usually shorter than

other spines in the same row (Figure 18). Dental plate

between 1.8 and 2.3 times longer than broad, with

a wide vertical septum dividing each tooth foramen,

and dental papillae region limited to approximately

25 percent of the total plate length (Figure 19). Upper

arm plates broadly oval, with outer edges only slightly

curved and contiguous along distal edge of following

plate for about 45 percent of maximum breadth

(Figure 17). Disc granules closely packed, small and

spherical, covering oral interradial region entirely to

mouth shields and nearly to genital slits. Two tentacle

scales on each side of oral arm plate on many segments

from beginning of arm.

In contrast to other members of the genus, the

BREVIPES group is characterized by having a dental

plate that is relatively much shorter, and broader than

FIGURE 17.—Ophiocoma dentata; upper arm plates and arm

spines, about segment 15 (d.d. 19 mm).

long (Figure 19). It shows a very small semicircular

region for the tooth papillae and wide flat septa which

divide the teeth foramina. The nature of this skeletal

ossicle together with other morphological features

listed above serve to separate the species in this group

from others in the genus.

Key to Species

1. Similar number of arm spines on each side of arm segments beyond disc; upper arm spines

surface white or yellow-white o. brevipes

Length of second and third arm spines equal to or more than breadth of proximal upper arm

plate; oral surface gray, brown or variegated 2

2. Arm spines conspicuously annulated in color (Figures 18, 20); 5 (seldom 4) arm spines

on segment 6 O. doederleini

Arm spines not annulated in color; 4 (seldom 5) arm spines on segment 6 O. dentata
NUMBER 5 1 13

FIGURE 18.—Ophiocoma dent at a (left) and Ophiocoma doederleini; lateral view of arm spines.

Both views from about segment 15; specimens from Eniwetok (d.d. 21 mm).

FIGURE 19.—Ophiocoma dentata; proximal (left) and distal

sides of dental plates (d.d. 21 mm).

DISCUSSION.—According to H. L. Clark (1921),

the BREVIPES group was the ancestral stock from which

both the SCOLOPENDRINA and PUMILA groups evolved.

Clark followed Matsumoto's (1917) speculation that

Ophiocoma brevipes was the most primitive species in

the genus, based on its limited number of dental papillae. There is no reason, however, to consider this character as necessarily primitive; just as likely it could be

a particular specialization related to the feeding habits

of the species. Likewise, there is no paleontological evidence to support H. L. Clark's suggestions that the

SCOLOPENDRINA and PUMILA groups evolved from

brevipes through (a) changes in pigmentation, (b)

changes in disc granulation size, (c) increase in the

number of dental papillae. Without better support, it

seems advisable to consider the BREVIPES group as a

relatively homogeneous species complex in the genus.

SPECIES EVALUATION.—As an aid in following the

somewhat complicated taxonomic revision of the

species in the BREVIPES group, synonymies are given

below with the major references included for each

species.

Ophiocoma brevipes Peters

Ophiocoma brevipes Peters, 1851, p. 466.—Lyman, 1865,

p. 92; 1874, p. 225; 1882, p. 172 (part).—Martens, 1870,

p. 252.—H. L. Clark, 1921, p. 129, pi. 13, fig. 7, pi. 34,

figs. 3, 4; 1938, p. 333; 1946, p. 342.—Ely, 1942, p. 56,

figs. 16a, b, pi. 13c—A. H. Clark, 1949, p. 53.

Ophiocoma brevispinosa Smith, 1876, p. 40.

Ophiocoma dentata Miiller and Troschel

Ophiocoma dentata Miiller and Troschel, 1842, p. 99, pi.

7, figs. 3,3a.—Liitken, 1859, p. 267.—Lyman, 1865, p.

70.—H. L. Clark, 1921, p. 121.—Koehler, 1922, p. 314.

(?) Ophiocoma squamata (Lamarck).—Miiller and Troschel,

1842, p. 102.

Ophiocoma insularia Lyman, 1861, p. 80; 1865, p. 89; 1874,

p. 225.—H. L. Clark, 1915, p. 291, pi. 15, figs. 3, 4.—Ely,

1942, p. 57, fig. 17, pi. 13a.
14 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Ophiocoma ternispina Martens, 1870, p. 252.—Lyman, 1874,

p. 225.

Ophiocoma brevipes Peters.—Lyman, 1874, p. 225; 1882,

p. 172 (part).—Loriol, 1894, p. 25, pi. 23, figs. 4, 4a.—

Koehler, 1922, p. 319, pi. 72, figs. 6-9; Matsumoto, 1917,

p. 343 (part), figs. 3a-c.

Ophiocoma variegata Smith, 1876, p. 39; 1879, p. 565, pi.

51, figs. 1-lc.

Ophiocoma marmorata Marktanner-Turneretscher, 1887,

p. 303, pi. 12, figs. 16, 17.—H. L. Clark, 1915, p. 294.

Ophiocoma brevipes var. variegata Smith.—H. L. Clark, 1921,

p. 130 (forma dentata and doederleini).

Ophiocoma brevipes var. insularia Lyman.—H. L. Clark,

1921, p. 130.

Ophiocoma scolopendrina (Lamarck).—H. L. Clark, 1909,

p. 524 (according to H. L. Clark, 1938, p. 559).

Ophiocoma insularia var. variegata Smith.—H. L. Clark,

1938, p. 330 (forma dentata and doederleini); 1939, p.

94; 1946, p. 246 (forma dentata and doederleini).—Ely,

1942, p. 60, pi. 13b.—Endean, 1957, p. 244.—Domantay

and Domantay, 1966, p. 53.

Ophiocoma doederleini Loriol

Ophiocoma doederleini Loriol, 1899, p. 30, pi. 3, fig. 2.—

Koehler, 1905, p. 60; 1922, p. 312, 321-322, pi. 72,

figs. 1-3.

REMARKS.—In 1938, H. L. Clark considered the

problem relating to various species which had been

designated as Ophiocoma brevipes and O. insularia.

On the basis of adult specimens from Lord Howe

Island, he described two color forms of Ophiocoma

insularia var. variegata. One form was characterized

by a reticulated disc pattern and was considered identical to Ophiocoma dentata described by Liitken

(1859); the other, with a spotted disc, was considered

similar to O. doederleini described by Loriol (1899).

For H. L. Clark, this appearance of two apparently

sympatric color forms confirmed the relationship between Liitken's and LorioPs species. He stated that

they were "easily recognized but seem to be unquestionably mere color forms of variegata" (H. L. Clark,

1946, p. 246). Recent examination of specimens from

several other Indo-Pacific localities has revealed, however, that H. L. Clark's interpretation requires

modification.

At Eniwetok, specimens with a gray, reticulated disc

pattern and very definite annulated arm spines were

collected together with specimens having a brownish

disc covered with blackish spots but lacking annulated

arm spines (Figures 20, 21). The pigmentation of the

•••• •

wi : •---•" *•-* E

IBfa fM fe #«

W I t

i If jflr

FIGURE 20.—Ophiocoma doederleini; upper side of specimen with reticulated disc pattern

(d.d. 23 mm).
NUMBER 51 15

FIGURE 21.—Ophiocoma dent at a; upper side of specimen

with spotted disc pattern (d.d. 26 mm).

disc at first recalled H. L. Clark's (1938) color forms,

dentata and doederleini, respectively. Clark, however,

had not mentioned the appearance of annulated arm

spines on either of his Lord Howe Island forms, although Loriol (1899) reported this feature in his

original description of O. doederleini. Moreover, the

occurrence of another color variety from Eniwetok

(Figure 22) corresponded closely with Koehler's

(1922) redescription and figures of the type-specimen

of O. doederleini. Koehler had compared the type with

specimens of O. dentata (as O. brevipes) and noted

that there were small black spots irregularly arranged

on the disc of O. doederleini and that "each of them

is surrounded by a lighter circle, a feature which Loriol

did not notice" (Koehler, 1922, p. 321).

When the Eniwetok specimens having the reticulated disc and annulated arm spines were compared

with the specimen having spots encircled with a lighter

outline and also having annulated arm spines, close

morphological similarity was revealed. In contrast,

several differences aside from pigmentation were noted

between these specimens and those which lacked the

annulated arm spines. First, a difference in the arm

spine sequence was noted (see Table 2). Seven specimens with annulated arm spines (Ophiocoma doederleini) were compared with five specimens without an378-616 O—70 2

FIGURE 22.—Ophiocoma doederleini; upper side of specimen

with spotted disc pattern (d.d. 19 mm).

nulated arm spines (Ophiocoma dentata). Differences

between the two species on the basis of the sequence

of arm spines are given below:

Ophiocoma doederleini

Four arm spines on segment

4.

Four or five arm spines on

segment 6.

Five spines on segments 7

and 8 (d.d. more than 12

mm); five out to segment

14 with increase in size.

Four arm spines as far as

segments 32 to 38 (d.d.

13—14 mm) and out to

approximately segment 55

in a 24-mm specimen.

Ophiocoma dentata

Three and four arm spines on

segment 4.

Four spines on segment 6.

Five spines on segments 7

and 8 (rarely five, when

d.d. more than 20 mm);

five out to segment 13

(d.d. more than 23 mm).

Four arm spines as far as

segment 17 (d.d. 13-14

mm) and out to approximately segment 25 in a 24-

mm specimen.

The above data support Koehler's (1922) findings.

His examination of the type of doederleini revealed the

presence of five arm spines on each side of the arm

segments at the base of the arm, dropping to four spines

some distance from the arm base. For dentata (as

brevipes) he noted, however, that five arm spines were

quite unusual and four spines did not occur far from

the arm base.
16

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE 2.—Arm spine sequence of (a) Ophiocoma dentata and (b) O. doederleini

ARM SPINE SEQUENCE

28-

26-

24-

22-

20-

18-

16-

14-

12-

10-

24-

22-

20-

18-

16-

14-

12-

10-

8-

1 234567 8 91011121314151617181920212223242 5 30 35 40 45 50 55 60

arm segment

.-••I' l

1234567 8 91011121314151617181920212223242 5 30 35 40 45 50 55 60

• 3 D 4 • 5 arm segment

number of arm spines

In addition, Koehler reported that the breadth of

the arms of doederleini was greater than that of dentata (as brevipes) due to a greater length of arm spines

as well as a greater breadth without arm spines. To

verify this, the arm span (composed of the length of

longest arm spines on each side of segment, the breadth

of the aboral arm plate, and the breadth of the lateral

plates) was analyzed, taking the tenth segment beyond

the disc edge for comparison and using the specimens

determined as dentata and doederleini from Eniwetok

(see Table 3). The percentage of the total arm span

occupied by the longest arm spines, aboral plate

breadth, and lateral arm plates is given for each specimen examined.

The percentage means of the total arm span occupied by the arm spines differed significantly between

the two species (t=4.4, 11 degrees of freedom), with

specimens of dentata having a range from 54 to 61

percent and doederleini having a range from 61 to 65

percent. The difference in the percentage means of the

arm span taken up by the breadth of the aboral arm

plate showed an opposite trend: the aboral arm plate

of dentata occupied a significantly greater part of the

arm span than that of doederleini (t—6.3, 11 degrees

of freedom), and no overlap between the two samples

was noted. Comparison of the total arm span for the

two species supports Koehler's contention that doederleini has a relatively greater arm span than dentata

for specimens of comparable size. For example, the

arm span of a 26-28-mm (d.d.) specimen of dentata

was 13.1 mm, while for a smaller specimen of doederleini (d.d. 24 mm), the arm span was 15.2 mm.

Further evidence for the separation of the two

species resulted when the Eniwetok specimens were

compared with several specimens identified as

Ophiocoma brevipes from Cocos-Keeling (USNM

E7450) and those identified as O. insularia var.

variegata forma dentata and doederleini by H. L. Clark
NUMBER 51 17

TABLE 3.—Arm span (10th free segment) of Ophiocoma dentata and O. doederleini

from Eniwetok

Disc diameter

(nun)

12-15

22

23.5

25-27

26-28

Range: 12-28

X

9

11-12.5

14

19.5

21.5

23

24

Range: 9-24

X

»;

Ophiocoma dentata (N=5 )

Percent spine

length

56

61

60

55

54

54-61%

57. 2%

3. 12

Percent aboral

plate

26

28

27

32

28

26. 32%

28. 2%

2.26

Percent lateral

plates

18

11

13

13

18

Ophiocoma doederleini (N=7 )

64

61

62

62

63

63

65

61-65%

62. 9%

1.39

20

22

22

24

21

22

21

20-24%

21.8%

1.30

16

17

16

14

16

15

14

Total arm

span (mm)

7.4

11.9

12.0

11.4

13.1

7.0

8.3

10.7

11.7

13.7

14.4

15.2

(1938, 1946) from Lord Howe Island (MCZ 5228,

5227). In both cases there are specimens with reticulated or spotted discs but lacking annulated arm spines.

The arm spine sequence for these specimens was similar

to that noted in the specimens determined as dentata

from Eniwetok and additional specimens from the

Hawaiian Islands.

It is apparent now that both dentata and doederleini have at least two color forms. The reticulated-disc

color variety of doederleini (Figure 20) is reported

here from Eniwetok for the first time. Additional specimens of this color form of doederleini also have been

collected by the author from the Marquesas Islands

(where dentata was not found and not previously reported) ; also, examples of this color form from the

Indian Ocean (Mauritius and Amirantes Islands) and

Tahiti are deposited in the United States National

Museum.

The spotted-disc color variety of doederleini can be

distinguished from that of dentata by the presence of

white rings around the disc spots as well as by the

presence of annulated arm spines. It is quite evident

after reexamination that the specimens which H. L.

Clark (1938, 1946) considered as doederleini represent

merely a spotted variety of dentata and are not conspecific with Loriol's species. Furthermore, it is evident

that the reticulated specimens (with annulated arm

spines) from Eniwetok, the Marquesas, and other

Indo-Pacific localities differ from those reported by

H. L. Clark (1938, 1946) as O. insularia var. variegata

forma dentata. The same is probably true in the case

of Liitken's (1859) specimens of O. dentata from the

Nicobar Islands, and Marktanner-Turneretscher's

(1887) reticulated form described as Ophiocoma marmorata. With the exception of the reticulated disc pattern, neither of these specimens was reported as having

annulated arm spines or more than four arm spines. In

these and other respects they agree with the external

features noted for Ophiocoma dentata as originally

described by Muller and Troschel.

The status of Muller and Troschel's species, Ophiocoma dentata, has been determined after examination of the type-specimen deposited in the Zoologisches

Museum Berlin (No. 931). The following is a clarification of the taxonomy of this species. Lyman (1865,

p. 70) stated that Muller and Troschel's Ophiocoma

dentata was invalid, appearing to be "only a middling

sized Ophiocoma echinata." Liitken (1859) described
18 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

additional specimens from the Nicobar Islands (see

above) which he considered O. dentata. Subsequent

reports, especially by Lyman (1882) and H. L. Clark

(1921), considered Liitken's specimens to represent a

species different from that of Miiller and Troschel.

The type-specimen of dentata, however, reveals characters which not only indicate that Lyman was mistaken in considering it as O. echinata but confirms the

fact that it belongs in the BREVIPES group of Ophiocoma and also supports the conclusion that Miiller

and Troschel's dentata is conspecific with Lyman's

(1861) Ophiocoma insularia and Smith's (1876)

Ophiocoma variegata. Of primary importance is the

similarity in the nature of the arm spines and their nonalternating sequence. Examination of several of

Lyman's syntypes of insularia at the Museum of Comparative Zoology, Harvard, and data sent by Ailsa M.

Clark on Smith's type of variegata substantiate the conspecificity of these species with dentata. Furthermore,

the species identified as Ophiocoma ternispina by Martens (1870) from the Philippines (Flores) cannot, on

the basis of its description, be separated from dentata,

and examination of comparative material from that

locality suggests that ternispina is synonymous with

dentata.

The description of Ophiocoma squamata (Lamarck)

by Miiller and Troschel (1842) certainly suggests dentata. As Lyman (1874, p. 225) mentioned, however,

the type-specimen of squamata was lost, so the brief description could be of either brevipes or dentata.

The variability in the color of the aboral surface occurring in O. dentata has, as I have pointed out, resulted in the previous establishment of new species and

color varieties. The aboral surface of the disc and arms

may be either variegated, with brown and white or

dark gray and white, or they may be uniformly brown

or gray. Orally, the color is generally lighter brown or

gray, seldom white. The very uniformly dark gray

variety is typical of the specimens described as O. insularia by Lyman. In the Hawaiian Islands and eastern

part of the Indo-Pacific many specimens show a uniformly dark gray color as adults, although younger

specimens are often variegated aborally. The color

forms in which the arms are variegated or marbled

brown with gray and white, the disc pattern reticulated

and the arm spines, while not annulated, but broadly

banded, appear to be more common in the west-central

Pacific and in the Indian Ocean.

Specimens identified by Balinsky (1957) as Ophiocoma insularia from Inhaca Island, Mozambique, and

reexamined by the author are considered to be O. pusilla (Brock), as has been proved to be the case in several other instances based on published reports and in

museum collection records (see pages 27-28).

A species syntopic with O. dentata and often confused with the latter is O. brevipes Peters. H. L. Clark

(1938, 1946) was able to distinguish the two species

after his earlier (1921) attempts at separation were

inconclusive. Ely (1942) also correctly distinguished

the two species based on Hawaiian specimens. Lyman

(1874) unfortunately had confused the issue when he

commented on the type-specimens of O. brevipes, O.

ternispina, and O. insularia (the last two species are

now considered O. dentata). In reference to brevipes

he stated, with regard to the number and length of

the arm spines, "five spines occur on the first eight

joints, and then four, and .. . the upper . . . the

longest" (Lyman, 1874, p. 225). My own examination

of five of Peter's (1851) syntypes (ZMB 961, 962,

4660) having disc diameters of from 12 to 18 mm

showed (a) an arm spine-sequence of 3-3-3-4 for the

first four segments with five and /or six spines to segment 10 and then four spines continuing distally well

beyond segment 30, and (b) in no case the upper arm

spine longest, rather the third spine often the longest

in the row. The arm spine sequence for these typespecimens closely parallels that found on specimens

from a number of Indo-Pacific localities (see Table 4).

Separation of brevipes from dentata and doederleini

can be made by comparing the arm spine sequences

for specimens of similar size (see Tables 2 and 4).

Equally good as a distinguishing character is the relationship between the maximum arm spine length and

the breadth of the upper (aboral) arm plate: in O.

brevipes the longest arm spine rarely exceeds, and

usually is less than, the breadth of the arm plate; in

comparison, O. dentata and O. doederleini have the

longest arm spine greatly exceeding the breadth of the

upper plate. A third means of separating O. brevipes

from the other two species is by differences in the

pigmentation: O. brevipes is nearly all white or light

cream colored on the oral surface of arms and mouth

plates, whereas the other two species show gray, brown,

or variegated coloration on the oral surface.

2. PICA Group

Three species are considered in the PICA group of

Ophiocoma: O. longispina H. L. Clark, 1917, in south-
NUMBER 51 19

TABLE 4.—Arm spine sequence of Ophiocoma brevipes

Ophiocoma

brevipes ARM SPINE SEQUENCE

5 6 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 30 35 40 50 60 70

segment number

M B 3 l-x-:-:-:-M 5

I I 4 S O 6

number of arm spines

eastern Polynesia (Easter and Pitcaim Islands), and

O. pica Miiller and Troschel, 1842, and O. pusilla

(Brock, 1888), both in the Indo-Pacific. These three

species are known to occur together only at Pitcaim

Island.

DIAGNOSIS.—Four to seven arm spines on each side

of proximal arm segments beyond disc margin; second

or third spine in row longest (Figure 23); spines tapering and elongate. Dental plate 2.3 to 3.0 times longer

than broad; dental papillae region occupying one third

of total plate length; septa dividing tooth foramina

flat and widened in O. pica and O. longispina but

narrow in O. pusilla (Figures 24—26). Upper arm

FIGURE 23.—Ophicoma pica; arm spines from segment 15

(upper spines at left, lower spines at right).

FIGURE 24.—Ophiocoma pica; proximal side of three dental

plates from different specimens (d.d. 15-19 mm).
20 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

plates with convex or median truncated distal edge,

narrowing proximally, with even, tapering lateral margins (Figures 27-29). Disc granules small, rounded,

uniform in size, closely packed, and extending over part

of oral interbrachial region. Two tentacle scales, the

outer larger and tapering toward tip.

FIGURE 25.—Ophiocoma longispina; proximal (left) and

distal views of dental plates (d.d. 10 mm).

FIGURE 27.—Ophiocoma pica; upper arm plates and lateral

arm plates with spines removed, including segment 15 (d.d.

19mm).

FIGURE 26.—Ophiocoma pusilla; proximal side of dental

plate (d.d. 7.5 mm).

DISCUSSION.—Similarity in the size and shape of the

disc granules, regularity and sequence of the arm

spines, number of tentacle scales, length-to-breadth

ratio of the oral shields, and shape of the upper and

lower arm plates suggest inclusion of the three species

in the PICA group of Ophiocoma.

FIGURE 28.—Ophiocoma longispina; upper arm plates with

some spines attached. Easter Island specimen (d.d.

10 mm).
NUMBER 51 21

FIGURE 29.—Ophiocoma pusilla; upper arm plates, segments

9-14 (d.d. 6 mm).

Variation in the thickness and length of the arm

spines, pigmentation, number of oral papillae, and certain features of the oral and dental plates serve to distinguish the three species.

In contrast to species in the other groups of Ophiocoma, those in the PICA group show some differences

in the morphological features of the oral and dental

plates. The oral and dental plates of O. longispina are

intermediate between those of O. pica and O. pusilla.

It is evident that pusilla shows the greatest divergence

from the typical Ophiocoma condition in the nature

of the oral plate. A comparison of the oral and dental

plates of the three species will now be considered.

Oral plate. Murakami (1963, p. 28, pi. vn, figs. 11,

12, 15, 16) described and illustrated this plate for pica

and pusilla (as latilanxa). In pica the abradial muscle

area has well-defined ridges and grooves, and these interrupt or break into the midproximal edge of the muscle surface. In longispina these ridges and grooves are

reduced, and there is a less-marked interruption of the

midproximal edge of the muscle surface (Figure 30).

In pusilla, unlike any other species of Ophiocoma, the

ridges and grooves are absent, and the proximal edge

of the muscle area curves inward but is uninterrupted.

FIGURE 30.—Ophiocoma longispina; abradial surface of oral

plate (d.d. 9 mm).

In addition to the abradial surface, Murakami also

noted that the oral plate of pica was "higher than long"

while that of pusilla (as latilanxa) was "rather low and

about as long as high." Murakami's "length" was measured along the oral-aboral axis of the plate, and his

"height" was measured along the distal-proximal axis.

The oral plate of longispina is about as high as long

(Figure 30). The adradial muscle scar was described

by Murakami (1963) for pica as "very narrow and

somewhat J-shaped," while that of pusilla (as latilanxa) was "narrow and elongate S-shaped." The

adradial muscle of longispina resembles pica in having

the oral part curved to almost form a J-shape (Figure 31).

Dental plate. Murakami (1963, pp. 26-27, pi. Ill,

figs. 2, 3) described and illustrated this plate for pica

and pusilla (as latilanxa). The dental plate of pica

was said to be "two and a half times as long as broad

somewhat slipper-shaped as that of O. latilanxa."

Further examination of the dental plate for both

Key to Species

1. Arm spines very fragile, hollow; 3 (seldom 4) oral papillae on each jaw angle O. pusilla

Arm spines not fragile, solid; 4 (sometimes 5) oral papillae on each jaw angle 2

2. Disc variegated with yellowish lines and yellow spot on each side of arm base of disc; lower

arm plates lighter along distal edge O. pica

Disc uniformly blackish; lower arm plates near disc uniformly dark o. longispina
22 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

species shows that the expanded oral portion of the

dental plate of pica is not characteristic as Murakami

indicated; rather, this portion of the plate is usually

straight or tapering inward (Figure 24). Further,

there is a difference in the nature of the septa dividing

the teeth foramina: in pica, the septa are flattened and

wide, while in pusilla they are narrow and compressed

(Figures 24, 26). The dental plate of longispina has

the same septal characteristics as that of pica but shows

the evident expanded oral portion (Figure 25) similar

to pusilla.

In thickness, the arm spines of longispina appear to

be intermediate between those of pica and pusilla.

They are not nearly as robust as those of pica, and

they show a small lumen, in contrast to the nearly

solid spines of pica and the very hollow spines of

pusilla.

With the exception of pica we know nothing about

the larvae of this group. Mortensen (1937) did show

that the larval skeleton of pica (as lineolata) differs

significantly from other members of the Ophiocominae

(Ophiocomina nigra, Ophiocoma echinata, O. erinaceus, and O. scolopendrina). More recently, it has been

found to differ from that of Ophiocoma pumila as well.

SPECIES EVALUATION.—Because of the taxonomic

changes necessitated in review of the PICA group, rather

detailed species evaluations are presented for Ophiocoma longispina and O. pusilla. A clarification of the

taxonomy of these two species is presented below.

Ophiocoma longispina H. L. Clark

Ophiocoma insularia var. longispina H. L. Clark, 1917, p.

441.

Ophiocoma brevipes var. longispina H. L. Clark, 1921, p.

131.

Ophiocoma insularia longispina H. L. Clark: Downey, 1969,

p. 104.

MATERIAL EXAMINED.—Easter Island: USN M E647

(type, Shore, 21 December 1904, Albatross collection);

BPBM, no numbers (3: two specimens from west coast,

between Hanga Roa and Hanga Piko, tidepool, 0-2

feet, 25 January 1969, and a specimen having no specified locality, both collected by J. E. Randall). Pitcairn

Island: BPBM, no number (1, Sta. PIT vni, off south

coast, coral bottom, 20-25 fathoms, dredge haul 4,

20 October 1967, collected by D. M. Devaney).

DIAGNOSIS (based on specimens having disc

diameters of 9-12 mm).—Arm spines long, tapering;

sequence: 3-3-4-4(or 5)-4(or 5)-5-5-5-5-5, and four

spines as far as segments 29 or 32, decreasing to three

spines on distal segments. Upper arm spines longest,

4 to 6 mm, equal to length of four segments (Figure

32). Arm four to five times disc diameter in length.

Disc granules small, rounded, closely packed, covering

radial shields and extending some distance into interradial region. Upper arm plates broadly rounded and

widest distally, inwardly tapering proximally, fanshaped, slightly broader than long in proximal part

of arm, becoming longer than broad on distal segments

(Figure 28). Lower arm plates in proximal part of

arm broader than long, distal border rounded medially

(although sometimes with slight central concavity)

with moderately acute lateral edges and incurved sides

directed toward proximal edge (Figure 35). Tentacle

scales two, of about equal length, outer widest, both

tapering toward tip (Figure 35). Oral shields longer

than broad, ovate. Adoral shields triangular, with

widest angle proximally directed (Figure 33). Usually

four oral papillae, outer broadest, overlying part of

buccal tentacle scale (Figure 33). One to four additional papillae above (oral to) jaw apex. Five to ten

dental papillae. Teeth, three or four each jaw, narrow

with hylinated tips. Dental plate 2.4 to 2.9 times longer

than broad; septa dividing teeth foramina wide and

flat; dental papillae region widened, occupying about

one third of total length (Figures 25, 34). Oral plates

(jaws) : abradial muscle surface with evidence of

shallow ridges and grooves, outer margin interrupted

(Figure 30); adradial muscle surface J-shaped (Figure 31). Pigmentation: blackish-brown in alcohol, only

slightly darker above than below; borders of oral

shields and dental and oral papillae whitish.

Size range examined: disc diameter, 9 to 14 mm;

arm length, 45 to 60 mm.

FIGURE 31.—Ophiocoma longispina; adradial surface of oral

plate (d.d. 9 mm), h, Adradial muscle scar.
NUMBER 51 23

FIGURE 32.—Ophiocoma longispina; aboral side of type-specimen (d.d. 10 mm).

FIGURE 33.—Ophiocoma longispina; oral mouth sectors of type-specimen (d.d. 10 mm).

DISCUSSION.—The original description of this species by H. L. Clark (1917) was based on a single specimen collected at Easter Island. Clark was unsure of the

status of this ophiuroid. He correctly noted several

differences from specimens of O. insularia ( — dentata)

also collected at Easter Island but he provisionally left

the specimen as a variety {longispina) of that species.

Later, Clark (1921) again mentioned this form, but

he added no further information, having only transferred O. insularia to O. brevipes and making

longispina a variety of the latter. Recently, Downey

(1969) listed Ophiocoma insularia longispina H. L.

Clark in her type catalog.

Failure to recognize the specific taxonomic position

of longispina was corrected when additional specimens

were made available to the author by Dr. J. E. Randall,

who visited Easter Island in January and February

1969. Three specimens of longispina collected syntopically with six specimens of O. dentata allowed further

comparison of the two species and, most importantly,

made examination of internal characters possible. This

provided convincing evidence for the recognition of

longispina as a separate species and led to its recognition from Pitcairn Island.

The additional specimens show that longispina can

be distinguished from dentata (with which it was

originally allied) in the following ways:

(1) Greater length of the arm spines (suggested by

H.L.Clark, 1917).
24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

(2) Different sequence of arm spines: longispina

has four spines on segment 3 and five or four spines

on segment 4; dentata has only three spines on segment

3 and four spines on segment 4. Also, longispina has a

FIGURE 34.—Ophiocoma longispina (left) and O. dentata;

proximal side of dental plates, both from specimens collected

at Easter Island (d.d. 10 mm).

FIGURE 35.—Ophiocoma longispina; oral arm plates, tentacle

scales, and arm spines (d.d. 12 mm).

greater number of segments with four spines than

dentata, even when specimens of the latter species

are larger. For example, four specimens of longispina

from Easter Island (including the type), with disc

diameters of from 9 to 14 mm, had four spines as far

as segments 29 to 35. Four specimens of dentata from

the same locality, with disc diameters 13 to 23 mm, had

four arm spines only as far as segments 18 to 24.

(3) Difference in shape of the arm spines: longispina with more-elongate, tapering spines (Figure 32),

in contrast to the broader, stubby, more truncated

spines of dentata (Figures 17, 18).

(4) Disc granulation: longispina with portions of

the oral interradial region free of granules, whereas

there is nearly complete granulation of this region in

dentata (and in all species in the BREVIPES group). In

both species the granules are approximately the same

size but they appear less closely packed in longispina.

(5) Differences in the size and shape of the dental

plates (Figure 34) : length-to-breadth ratio and area

occupied by the dental papillae are greater for longispina than for dentata.

(6) Differences in shape of upper arm plate: longispina with more angular lateral margins (Figure 28),

compared to the broadly rounded lateral margins of

dentata (Figure 17).

(7) Difference in shape of the oral shields: in

longispina the oral shields are relatively longer than

broad, compared to the more rounded ones of dentata.

Several characters separate longispina from its apparently closest relative, O. pica. Pigmentation provides a convenient way to distinguish the two species.

For pica there is a yellowish spot at either side of the

arm base on the disc. Usually there are also radiating

lines of yellow on the dark-brown background of the

disc, normally there is a considerable amount of yellow

on the proximal parts of the lower arm plates near the

disc, and there also is yellow on the peripheral sides of

the oral and adoral shields. In contrast, O. longispina

is uniformly dark blackish brown. Morphologically,

longispina has a greater portion of the oral interradial

region of the disc granulated, and the relative length

of the arm spines is greater than for pica. Furthermore,

on longispina the two tentacle scales are the same

length (Figure 35), whereas on pica the inner scale

is narrower and longer than the outer one. Differences

in the oral and dental plates of the two species have

been discussed above.
NUMBER 5 1 25

Ophiocoma pica Miiller and Troschel

Ophiocoma pica Miiller and Troschel, 1842, p. 101.—Loriol,

1894, p. 28 (with a complete bibliography to that date).—

H. L. Clark, 1915, p. 293; 1921, p. 127, pi. 13, fig. 8

(color); 1938, p. 333; 1946, p. 244.—Ely, 1942, p. 54,

figs. 15a,b, pi. 12b.—A. H. Clark, 1949, p. 51.—A. M.

Clark, 1952, p. 207; 1967, pp. 47, 55.—Balinsky, 1957,

pp. 26, 31.

Ophiocoma lineolata Miiller and Troschel, 1842, p. 102.—,

Loriol, 1894, p. 28 (with a complete bibliography to that

date).—Koehler, 1922, p. 324, pi. 73, figs. 1-4.—Mortensen, 1937, pp. 51-52, fig. 41 (larval skeleton), pi. 8, figs.

1-3 (larva).—Boone, 1938, p. 148, pi. 52.—Tortonese,

1953, p. 33.

Ophiocoma sannio Lyman, 1861, p. 81; 1865, p. 91.

DIAGNOSIS.—The external features of O. pica have

been adequately described by several authors. Two

works which may be consulted are those of Lyman

(1865) and Ely (1942). Additional comments referring to the internal morphology of this species have

been presented in this paper in the discussion of the

PICA group, and characters separating pica from longispina have been given.

DISCUSSION.—This species, which is widely distributed throughout the Indo-Pacific (H. L. Clark, 1921),

appears to be primarily a coral dwelling form. In the

Hawaiian Islands, Johnston Island, the Tuamotus, and

Pitcairn Island, I found it most commonly between the

branches of the scleractinian coral Pocillipora meandrina var. nobilis. I did not find Ophiocoma pica at

the Marquesan Islands in 1967, and found no evidence

of Pocillopora meandrina there; however, at the northern Tuamotu Islands of Takaroa and Manihi, near the

Marquesas, I found O. pica within the branches of

P. meandrina. Additional specimens were collected

from this same coral species at Pitcairn Island. A. H.

Clark (1952) reported the species from the coral Stylophora mardax at Rongerik Atoll, Marshall Islands.

My own collecting of O. pica indicates that small specimens, especially, are most common in the coral habitat.

Specimens less than 15 mm (d.d.) were found in

Pocillopora, but larger specimens occasionally were

found under rock or dead coral rubble as well as in

living coral.

One still finds modern descriptions of Ophiocoma

pica under the name O. lineolata Desjardins, even

though the conspecific nature of the two species was

recognized by Lyman (1865) after examination of the

two type specimens and after unanimous agreement

that the two species were synonymous. The continued

use of the name O. lineolata (although appropriately

descriptive) is unacceptable since Miiller and Troschel

were the first to publish and describe both species in

1842, and Lyman clearly established pica as the nominal species.

Ophiocoma pusilla (Brock)

Ophiomastix pusilla Brock, 1888, p. 499 (Amboina).—

Pfeffer, 1900, p. 85 (Ternate, no other data) .—Koehler,

1905, p. 65, pi. 6, figs. 9, 10, pi. 13, fig. 3 (Moluccas).—

Ailsa M. Clark, 1967, p. 45, fig. 5 (Red Sea, Aqaba).

Ophiocoma pusilla (Brock).—H.L.Clark, 1921, p. 131.

Ophiocoma latUanxa Murakami, 1943a, p. 194, fig. 13

(Palao); 1943b, p. 217 (Ryukyu).

Ophiocoma sp.—Ailsa M. Clark, 1952, p. 208 (Red Sea).

Ophiocoma insularia Lyman.—Balinsky, 1957, p. 26 (Mozambique).

Ophiocoma insularia var. variegata Smith.—H. L. Clark,

1938, p. 330 (part, Lord Howe Island).

Ophiocoma scolopendrina (Lamarck).—H. L. Clark, 1921,

pi. 13, fig. 9 (color) (Torres Strait).

STATUS OF TYPE MATERIAL.—In the original description of Ophiomastix pusilla, Brock gave the size of his

largest individual as 8 mm (d.d.), with a disc-diameter-to-arm-length ratio of 1:5. Aside from this, there

was no indication that a specific individual was being

described nor was there any type designation. Brock

mentioned only, "wurde von mir in zahlreichen Exemplaren in Amboina erbeutet" (Brock, 1888, p. 500).

Dr. P. Kuenzer at the Gottingen Museum informed

me that Brock's original specimens deposited there

were destroyed in World War II. Apparently, however,

two specimens from Brock's original series were transferred to the Zoologisches Museum Berlin prior to

that time. These specimens have been examined and,

although smaller than Brock's largest specimen, they

are considered part of the syntypic series. The fact that

the two specimens differ slightly in certain external

characters (with one showing more evidently the

characters originally presented by Brock) leads me to

designate a lectotype in this paper. Some of the more

important features and variations of the two specimens

are given below in the description of the species.

LECTOTYPE.—ZMB 5429 (Marine Tiergruppen);

disc diameter, 4 mm. Label with specimen: "Ophiomastix pusilla, Amboina 5429 Brock. Type."

PARALECTOTYPE: ZMB 4777 (Marine Tiergruppen) ; disc diameter, 3.5 mm.

DIAGNOSIS—Disc diameter up to 10 mm; sexually

mature specimens from 6 mm (Eniwetok, September
26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

1966). Small, uniformly distributed granules entering

oral interradial area but not reaching oral shields and

leaving an area near genital openings with exposed

scales (paralectotype with several widely spaced spiniform granules among normal granules near edge of

disc aborally). Two tentacle scales each side of proximal arm segments (lectotype with two scales to segment 22; larger specimen, d.d. 7.5 mm, with two scales

to segment 40) ; outer scale largest. Arm spines typically long, tapering, fragile, and hollow (lumen of

spine greater than thickness of spine wall) also not

smooth; occasional thickening of one to three adjacent,

next to uppermost arm spines occurring from segments

8 to 12; enlargement of outer part of these spines also

combined with increased length of these modified

spines, in alcohol appearing as a gelatinous epithelial

envelope around spine (lectotype with enlarged spines

only on one side of 10th segment of three arms;

paralectotype without enlarged spines). Arm spine

sequence for 7-mm specimen: 3-3-4-4(or 5)-5(or 4)-

5(or 6)-5(rarely 6)-5-5-5 for the proximal ten segments; beyond segment 6, development of fifth arm

spine on more segments with size increase to segment 20

(lectotype with five spines to segment 8) ; distally. number of spines 4 then, near arm tip, 3. Oral papillae 3,

less often 4, outer papilla broadest, its outer margin

overlapping inner edge of buccal tentacle scale.

Dental papillae in two and three rows, marginal

papillae slightly larger than medial ones; from 6

to 15 papillae depending on size (lectotype with

6-8 in two rows). One to four granular papillae

above (oral to) apex of each jaw. Dental plate

(Figure 26) with widened lower portion, narrow

septa dividing teeth foramina; length-to-width ratio,

2.3-2.7 : 1. Teeth 3 or 4; oralmost shortest and narrow, second and third longer and narrow; tips of teeth

hylinated. Oral shields longer than wide; length-towidth ratio, 1.2 to 1.7 : 1 (lectotype, 1.3 : 1; in no

case were these plates noted to be twice as long as

broad, as originally indicated by Brock). Adoral shields

widely separated, triangular, outer edge in contact

with ventral shield; limited to sides of mouth shields.

Oral plate (jaw) lacking ridges and grooves on abradial muscle surface (see Murakami, 1963, pi. vn, fig.

11). Upper arm plates with margin broadly arched

distally and tapering sharply proximally (Figure 29).

Lower arm plates with convex distal margin, tapering

proximally. Arms banded in most cases, dark brown

and lighter yellowish or white; dark aboral arm plates

often with various mottled pattern, or uniform tan to

black; oral surface of arms lighter than aboral surface.

Disc spotted, reticulated, or solid color (brown or gray),

usually with white spot on either side of each arm

base; periphery of disc sometimes gray with median

white area and a dark gray spot centrally located (lectotype with tan disc and lighter ambital area).

DISCUSSION.—Brock (1888) originally characterized pusilla as having club-shaped or claviform arm

spines. Unlike any other species of Ophiomastix, however, these arm spines occurred on the second rather

than the uppermost spine and only on a few adjacent

segments in the proximal region of the arm. Ophiomastix pusilla was considered different from other species

in the genus not only by the number, position, and

shape of its club-shaped spines but by its color, small

size, and presence of fine disc granules without disc

spinules. The combination of the fine, even covering of

granules and the transformed second row of arm spines

into clubs led Brock (1888) to consider Ophiomastix

pusilla as an aberrant species, possibly to be placed in a

separate genus.

Koehler (1905) reported two specimens from the

Siboga Expedition in the Dutch East Indies (Indonesia) which he compared with one of Brock's original specimens. Koehler's largest specimen, with a

disc diameter of only 5 mm (compared with Brock's

largest, 8 mm), showed only a partial development of

the club-shaped arm spines from the second row. It

was concluded that this characteristic was perhaps a reflection of the smaller size of the specimen, especially

since Koehler's smallest specimen revealed no trace of

claviform spines. In other respects the specimens were

essentially the same as those described by Brock.

H. L. Clark (1921) transferred the species to Ophiocoma on the basis that granules rather than spinules

on the disc outweighed the presence of clavate arm

spines as a generic character. He was inclined to believe the species might be the young of some larger and

as yet unknown Ophiocoma. Unknowingly, he gave

a color figure of pusilla—which was called Ophiocoma

scolopendrina juv. (H. L. Clark, 1921, pi. 13, fig. 9) —

wherein the limited presence and position of the swollen arm spines are clearly indicated.2

 This dry speci-

'A reexamination of one of the specimens (MCZ 3766;

d.d. 6.5 mm) confirmed the identity as O. pusilla. According

to one label, this specimen, collected at Mer Island, Torres

Strait, was drawn by a Mr. Gross. Other labels read:

"Ophiocoma scolopendrina? juv." and "May be young

erinaceus."
NUMBER 5 1 27

men shows the enlarged, next to uppermost arm spines

on the tenth segment of only two rays in contrast to

Clark's figure, which shows these spines on each side

of one segment of each ray.

The known distributional range of Ophiocoma

pusilla was expanded when A. M. Clark (1967) reported several specimens from the Red Sea and Gulf

of Aqaba. She continued to use the generic name

Ophiomastix, noting that several other species of

Ophiomastix had a continuous coat of granules with

spinelets intermingled. The typical absence of spinelets, however, is unknown in any species of Ophiomastix. Ophiocoma pusilla also was compared with

0. brevipes, and similarity was noted in color pattern

and extension of the fine disc granules to the oral side

of the disc. Considerable variation was found in the

number and, to a lesser degree, in the position of the

club-shaped spines. These modified spines were observed from the eighth to twelfth segments, usually on

two or three consecutive segments. In contrast to

Koehler's (1905) conclusion noted above, Miss Clark

found the clavate spines less conspicuous in the larger

(d.d. 7 mm) than in the smaller specimens at her

disposal.

Murakami (1943a) erected the species Ophiocoma

latilanxa from Palau Islands in the western Pacific;

and he reported additional specimens from Yaeyama

Island in the Ryukyu Group (Murakami, 1943b).

The type was described as small (d.d. 6.5 mm) and

covered with fine, dense granules which did not reach

the oral shield ventrally. The arm spines were slender

with the upper one or two quite long. No mention was

made concerning a thickening of the spines. Ophiocoma latilanxa was considered most closely related to

O. lubrica Koehler, 1898. It was distinguished from O.

lubrica, however, by having broad pentagonal lower

arm plates, more numerous dental papillae, and a

differently shaped oral shield. It should also be noted

that in Koehler's (1898) description of O. lubrica, the

arm spines were four in number, cylindrical, thick, and

blunt at the tip; in these respects they differed from

the spines of O. latilanxa as Murakami described

them. Although H. L. Clark (1921) considered O.

lubrica as a synonym for O. scolopendrina, the status

of O. lubrica awaits clarification by examination of the

type-specimens, deposited in Calcutta.

The description of Ophiocoma latilanxa did not

suggest relationship to Ophiocoma pusilla, primarily

because of the emphasis on the modified club-shaped

spines attributed to the latter species and of their absence in the former. Several new lines of evidence,

however, have suggested reconsideration, and the likelihood that the two species are conspecific.

First, several brittlestars described (by Balinsky,

1957) as Ophiocoma insularia from Inhaca Island,

Mozambique, were made available to me. On examination, however, the specimens proved not to be O.

insularia. Differences in the shape, size, and sequence

of arm spines, the nature of the dental and oral plates,

and the number of dental papillae indicated that the

specimens were quite distinct from any species in the

BREVIPES group of Ophiocoma. The specimens were

small, with a disc diameter less than 10 mm. One

specimen had peculiar dark circles, each of which was

surrounded by a lighter ring. This color pattern was

noted by Balinsky, and it led him to compare his

specimens with Ophiocoma delicata described by H.

L. Clark (1932). At my request, Ailsa M. Clark kindly

examined the type specimen of O. delicata, deposited

in the British Museum, and reported that the specimen

represented a species of Ophiarachna near mauritiensis

(family Ophiodermatidae). My own examination of

a paratype of Ophiocoma delicata deposited in the

Museum of Comparative Zoology, Harvard, agreed

with her determination. She suggested that Balinsky's

specimens (as Ophiocoma insularia) might be the

same species as a small specimen which she described

as Ophiocoma sp. from the Red Sea (A. M. Clark,

1952) and which she later united with additional

material from the Gulf of Aqaba as Ophiomastix

pusilla (A. M. Clark, 1967).

Second, in another collection of small ophiuroids

from Eniwetok atoll, Marshall Islands, I found specimens similar to those from Inhaca Island. The fact

that the Eniwetok specimens were sexually mature removed doubts that they were juvenile forms of some

larger species.

The relationship between both the Eniwetok and

Inhaca Island specimens and Murakami's Ophiocoma

latilanxa finally became apparent after a comparison

of the dental and oral plates. Murakami's (1963) description and figures of these plates for O. latilanxa

coincided remarkably well with those dissected from

the Eniwetok and Inhaca Island specimens.

A careful examination of the Inhaca Island specimens revealed the presence of several thickened arm

spines in one specimen. Instead of the presence of the

swollen clavate spines on the next to uppermost arm
28 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

spine, the enlarged spines were located on the third

or even fourth spine in a row. The thickened arm spines

appeared irregularly on one or both sides of two or

three segments on three arms only. The other three

larger and smaller specimens from Inhaca Island

lacked the swollen spines. Eniwetok specimens (four)

also had no modified arm spines. Examination of three

specimens (USNM E8620) labeled Ophiocoma brevipes var. variegata, from Yap Island (Caroline Islands), and identical with Eniwetok material of O.

pusilla showed the modified arm spines on only two

arms of one specimen.

Additional specimens (inMCZ) identified as Ophiocoma insularia var. variegata by H. L. Clark proved, on

examination, to be O. pusilla. These specimens are from

Green Island on the Great Barrier Reef (MCZ 3754,

1 specimen), Lord Howe Island (MCZ 5227, 1 specimen; 5229, 4 specimens) ,

3

 and Port Galera, Mindoro,

in the Philippine Islands (MCZ 4002, 1 specimen).

Final verification of the taxonomy of O. pusilla came

when two of Brock's original specimens of Ophiomastix

pusilla from Amboina and deposited in the Zoologisches Museum Berlin were made available through

the kindness of Dr. Gruner. These specimens left no

doubt that the specimens from Inhaca Island, Eniwetok, and other localities mentioned above were conspecific with Brock's species. Unfortunately, attempts to

examine Murakami's type specimens of Ophiocoma

latilanxa have been unsuccessful and correspondence

with Dr. Kikuchi of the Amakusa Marine Biological

Laboratory in Japan indicated that the type specimens

are lost.

Recent collections by the author reveal the presence

of Ophiocoma pusilla in several southeastern Polynesian localities, including Anaa, Manihi, and Puka Puka

Atolls in the Tuamotu group, and Pitcairn Island. A

specimen also was collected by Dr. John E. Randall

at Marcus Island in the north-central Pacific Ocean.

These specimens as well as those from Inhaca Island

and Eniwetok are, for the most part, deposited in the

collections of the Bernice P. Bishop Museum, Honolulu.

The retention of pusilla in the genus Ophiomastix on

the basis of the peculiar thickening of a few arm spines

is considered unwarranted in view of the differences

in the sequence of the arm spines (in Ophiomastix, but

not in pusilla, there is an irregular alternation of arm

spines similar to that noted for the SCOLOPENDRINA

group of Ophiocoma) and typical lack of disc spinules

in pusilla. This species, while showing several peculiar

features, is best considered as a member of the PICA

group of Ophiocoma. The relationship of O. pusilla

with other species in the PICA group has been discussed

above.

HABITAT.—Brock,(1888) gave no particular information on the habitat or depth at which his specimens

of pusilla were collected at Amboina. In his ecological

notes, Balinsky (1957, pp. 30-31) recorded some of the

major biotopes in which ophiuroids were found at

Inhaca Island, Mozambique. He reported Ophiocoma

pusilla (as O. insularia) from a coral reef environment

"in the infralittoral fringe," where it was listed among

the less-common and rare species. Further on, this species also was reported as common in another "more

tropical" reef area (Ponta Torres Reef) where the base

of the reef was very shallow. Dr. Balinsky has informed

me that this species favored dead coral heads. The

fragile nature of the arm spines and the fact that a

barnacle was found on one of the oral arm plates suggest that the species avoids contact with a coarse particulate substratum where repeated abrasion might

occur. Specimens from Eniwetok were collected from

relatively quiet water and were extracted from broken

pieces of coral at depths of from five to ten feet. Tuamotu specimens were collected from live and dead

coral heads, usually at the base of the broken coral.

Specimens from Pitcairn Island were dredged, with

broken coral, from 20 to 58 fathoms. As Koehler

(1905) suggested, a Siboga station depth record of 701

meters for this species probably is a mistake. It appears

that Ophiocoma pusilla is confined to the shallow sublittoral zone within a coral substratum.

3. PUMILA Group

The PUMILA group of Ophiocoma is represented by

three species: O. alexandri Lyman, 1860, in the tropical eastern Pacific; O. pumila Liitken, 1856, in the

tropical West Indies and tropical West Africa; and

O. valenciae Miiller and Troschel, 1842, in tropical

East Africa and the western Indian Ocean.4

* These specimens are among those designated by H. L.

Clark (1938, 1946) as Ophiocoma insularia var. variegata

forma dentata).

•Martens (1870, p. 250) listed O. valenciae from collections made at Fiji and Samoa in the Indo-Pacific, but this

listing is assumed to be based on erroneous data or species

identification. Pacific records require verification.
NUMBER 51 29

Ophiocoma alexandri has been reported from Baja

California (Santa Maria Bay) and the Revillagidedo

Islands to Ecuador and the Galapagos Islands. O.

pumila shows a wide distribution from insular and

mainland regions of the Caribbean, north to Bermuda

and south to Brazil, and off the west African

coast (Azores, Gulf of Guinea, Cape Verde Islands).

O. valenciae is known from the east coast of Africa to

Durban in the south, up into the Red Sea, and from

several localities in the Indian Ocean. With few exceptions, none of the species has been reported from

depths exceeding 25 meters.

DIAGNOSIS.—Four to seven arm spines on each side

of proximal arm segments beyond disc margin; second or third arm spine longer than uppermost (Figure 36). Dental plate 2.4 to 2.8 times as long as broad,

with a narrow vertical septum dividing each tooth foramen and dental papillae region occupying approximately 30 percent of the total plate length (Figures

37-39). Upper (aboral) arm plates oval, contiguous

along distal edge of following plate from 25 percent

to (rarely) 50 percent of maximum breadth of plate

(Figures 40, 41). Disc with rounded granules and

more-elongate, squat, spiniform granules interspersed

and not tightly packed (Figure 42), fewer extending

orally nearly to mouth shield and genital apertures.

Two tentacle scales on only a few proximal segments,

followed by a single scale on more distal segments.

Key to Species

1. Five arm spines seldom beyond segment 10 (d.d. over 6 mm) O. pumila

Five arm spines continuing beyond segment 10 (d.d. over 6 mm) 2

2. Light-colored stripe along middle of oral arm plates O. alexandri

No light-colored stripe along middle of oral arm plates O. Valencia*

DISCUSSION.—The three species in the PUMILA

group are typically pentamerous. According to H. L.

Clark (1921, 1946) the young of Ophiocoma alexandri

and O. pumila were thought to exist as both fiveand six-armed individuals in their smaller sizes. Morphological criteria established by A. H. Clark (1939),

Ailsa M. Clark (in Parslow and Clark, 1963), and the

present investigator strongly suggest, however, that the

small hexamerous ophiocomids should be separated

and placed in the genus Ophiocomella. A significant

point to be made here is that recent study indicates

that Ophiocomella exists in the hexamerous or pentamerous (rarely seven arms) form with the six-armed

form most common. Owing to the small size of ophiocomellids, external features relatively similar to small

specimens of the PUMILA group of Ophiocoma, and the

failure to recognize the existence of pentamerous individuals of Ophiocomella, there has been some confusion as to their taxonomic position.

Although a more complete discussion of the systematics and re-evaluation of the genus Ophiocomella

will be forthcoming, several morphological features

FIGURE 36.—Ophiocoma alexandri; proximal view of arm segment 14 with arm spines

(d.d. 18 mm).
30 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 37.—Ophiocoma pumila; proximal side of dental FIGURE 39.—Ophiocoma valenciae; proximal side of dental

plate (d.d. 12 mm). plate, broken (d.d. 13 mm).

FIGURE 38.—Ophiocoma alexandri; proximal side of dental

plate (d.d. 13 mm).

have been found which serve to differentiate that genus

from those species in the PUMILA group of Ophiocoma.

First, with few exceptions, Ophiocomella is characterized by an arm spine sequence of 2 or 2 and 3-3-3 or

3 and 4 for the proximal three segments. In a few cases

the pattern 3-3-3 and 4 or 2 and 3-3-4 has been obFIGURE 40.—Ophiocoma pumila; upper arm plates and

spines, from segments 12—17 (d.d. 13 mm).

served. In contrast, the three species of Ophiocoma in

the PUMILA group quite consistently show a sequence of

3-3-4 regardless of the size of the specimen.

Second, the oral plate (jaw) reveals a significant

difference in the two genera: for Ophiocomella there
NUMBER 51 31

FIGURE 41.—Ophiocoma alexandri; upper arm plates and

spines, from segments 15-20 (d.d. 17 mm).

FIGURE 42.—Ophiocoma alexandri; edge of disc showing

granules (d.d. 17 mm).

is characteristically an opening near the center of the

adradial muscle scar (Figure 43a,b); no specimens

of Ophiocoma, including all three species in the

PUMILA group have revealed this opening on the adradial surface of the oral plate (Figure 44a). The

functional significance of this aperature remains to be

defined. Its presence in the commonly self-dividing

(fissiparous) genus Ophiocomella and a similar feature in the fissiparous Ophiactis savignyi may suggest,

however, a relationship to the phenomenon of fissiparity. The opening is thought to lead to the water

vascular system.

In addition to morphological characters, species in

the PUMILA group of Ophiocoma show differences in

distribution from Ophiocomella. In the Indo-Pacific,

Ophiocomellasexradia (synonyms: Ophiocomaparva,

Ophiocomella clippertoni, O. schultzi, and Ophiomastix sexradiata) is widely distributed, however,

there is no representative of the PUMILA group in the

Indo-Pacific except in the western Indian Ocean,

where the range of Ophiocoma valenciae and Ophiocomella sexradia overlap (Balinsky, 1957). In the

eastern tropical Pacific, Ophiocomella has been reported from Clipperton Island (as O. clippertoni) and

the Galapagos Islands (as O. schmitti) by A. H. Clark

(1939). Geographic overlap of Ophiocomella and

Ophiocoma alexandri (based on examination of specimens in AHF, USNM, and MCZ) has been noted at

the Galapagos, Revillagidedo Islands (Clarion Island), western Panama (Secas Island), and Costa Rica

(Port Culebra and Parker Bay). Further north along

the Central American coast up to Baja California,

however, there is no evidence of Ophiocomella occurFIGURE 43.—Ophiocomella; abradial surface of oral plate (left) and adradial surfaces of oral

plates (middle and right) from specimens collected at Bermuda (dd. 7 mm). ;, Aperture through

adradial muscle scar.
32 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

ring, although Ophiocoma alexandri is well known.

In the Caribbean and throughout the West Indian

report of any small hexamerous ophiocomids from the

appear to be widely distributed, however, there is no

report of any small hexamerous ophiocomids from the

West African localities where Ophiocoma pumila has

been collected. There is some evidence that Ophiocomella and the young of Ophiocoma pumila and O.

alexandri share a similar habitat. Their syntopic association does not preclude different ecological niches,

but presently little is known concerning aspects of their

life histories.

The suggestion by H. L. Clark (1921, p. 124) that

species in the PUMILA group evolved "directly from

brevipes" based on a similarity in pigmentation, is

FIGURE 44.—Ophiocoma pumila; abradial (above) and

adradial surfaces of oral plates (d.d. 13 mm).

doubtful. Very marked differences in the dental plates,

the presence of only a single tentacle scale on all but

a few of the most proximal arm segments in species in

the PUMILA group, and differences in the size and extent of disc granules clearly separate representatives of

the two groups.

Within the group, valenciae and alexandri are more

alike in their arm spine sequences. Both species show

the development of six (up to seven in alexandri) arm

spines on segments near the disc and have a large

number of segments with five arm spines, and in both

respects differ from pumila. Furthermore, Ailsa M.

Clark (1966, p. 44) found that the ratio of arm length

to disc diameter for valenciae can range from 5.25 to

8.5 : 1. This range is well within that indicated by

H. L. Clark (1921, p. 123) for alexandri and pumila

and thus does not offer a character by which valenciae

can be separated from these species as he indicated in

his key.

In the PUMILA group, the third arm spine in the row

(counting from the bottom) is generally the longest,

being distinctly longer than the lower two spines on

those segments beyond the disc. This means that on

the tenth free segment (beginning with the first segment with a well-developed upper arm plate) the

longest spine for pumila is the next to uppermost in the

row, since in this species only four spines occur that far

out on the arm. For alexandri and valenciae, however,

with as many as five or six arm spines on the tenth free

segment, the longest arm spine is the third or fourth

spine from the top, respectively. Although this relationship is generally true, I have found some specimens of

valenciae having the fourth from the lowest arm spine

equaling or slightly exceeding the length of the third

lowest spine.

Development and larval rearing of O. pumila were

carried out by the author. It is significant that the

fertilized egg has a smooth membrane in contrast to

that of species in the SCOLOPENDRINA group and that

the larval skeleton shows body rods coming together

with the formation of small terminal and end rods

(Figure 16) in contrast to the condition noted by

Mortensen (1937) for the larval skeleton of O. pica.

4. SCOLOPENDWNA Group

The SCOLOPENDRINA group of Ophiocoma has the

greatest number of species in the genus and shows a

pan-tropical distribution: O. aethiops Lutken, 1859,
NUMBER 5 1 33

FIGURE 45.—Ophiocoma erinaceus; internal view, three

sectors of jaw (d.d. 28 m): r, teeth; s, dental papillae; t,

dental plate.

tropical eastern Pacific; O. "alternans" Endean, 1963,

subtropical southeast Australia; O. anaglyptica Ely,

1944, tropical central Pacific; O. echinata (Lamarck,

1816), tropical West Indies;5 O. erinaceus Miiller

and Troschel, 1842, tropical Indo-Pacific; O. macroplaca (H. L. Clark, 1915), eastern Indo-Pacific; O.

occidentals H. L. Clark, 1938, subtropical Western

Australia; 0. scolopendrina (Lamarck, 1816), tropical

Indo-Pacific; O. wendti Miiller and Troschel, 1842,

tropical West Indies.

DIAGNOSIS.—Three to five (rarely six) arm spines

on each side of proximal arm segments beyond disc

edge, with upper spine longest and often thickened; a

short distance beyond disc, arm spines alternate (typically three and four) either on opposite sides of the

same arm segment or on adjacent segments (Figure

46). Dental plate between 2.4 and 2.6 times as long as

broad, with very narrow vertical septa dividing the

teeth foramina, and dental papillae region occupying

one third of the total plate length (Figures 45, 47).

Upper (aboral) arm plates with uneven lateral borders where arm spines alternate on each side of same

segment (Figure 48). Disc granules coarse and spherical, except in O. anaglyptica where they may be more

flattened. One or two tentacle scales on each side of

oral arm plates.

FIGURE 46.—Ophiocoma erinaceus; distal view of 10th arm

segment (d.d. 20 mm).

FIGURE 47.—Ophiocoma anaglyptica; proximal (left) and

distal surfaces of dental plate (d.d. 11 mm).

5

 Ophiocoma echinata has been reported from Liberia

(H. L. Clark, 1921) but that record requires further

verification.

FIGURE 48.—Ophiocoma erinaceus; aboral view of 10th arm

segment with upper arm plate and arm spines (d.d.

15 mm).
34 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Key to Species

1. A group of exposed and enlarged scales in oral interbrachial disc region; disc granules often

flattened, pavement-like; fourth (upper) arm spine flask-shaped (Figure 49).

O. anaglyptica

No enlarged scales in oral interbrachial disc region; disc granules rounded; upper arm spines

not flask-shaped 2

2. Four spines on each side of third arm segment O. macroplaca

Three spines on each side of third arm segment 3

3. Oral surface of arms, especially proximally, white or yellow-white, sometimes variegated but

never all black; Indo-Pacific O. scolopendrina

Oral surface of arm, including proximal area, partly or all black, reddish, or dark brown

to tan " 4

4. Two spines on each side of first arm segment; Caribbean O. wendti

Three spines on each side of first arm segment 5

5. Upper arm spine, on side with 3 spines, as long as or longer than upper arm spine on opposite

or adjacent side of segment with 4 arm spines; eastern tropical Pacific O. aethiops

Upper arm spine on side with 4 spines longer than upper arm spine on opposite or adjacent

side of segment with 3 arm spines 6

6. Twenty to 36 disc granules per square mm 7

Nine to 16 granules per square mm; Indo-Pacific 8

7. Disc granules entering as V-shaped group into oral interradial region, leaving scales usually

exposed between disc and oral shield; West Indies O. echinata

Disc granules covering all but small portion of oral interradial region, not leaving scales exposed

between disc and oral shield; Australia O. "alternans"

8. Oral surface of arms and spines reddish brown; Western Australia O. occidentalis

Oral surface of arm and spines black or dark gray; Indo-Pacific O. erinaceus

DISCUSSION.—The sequence of arm spines on particular segments has been of considerable help in distinguishing several species of Ophiocoma in the

SCOLOPENDRINA group. Arm spines on the first several

proximal segments characteristically remain constant

throughout the growth of an individual for all species

of Ophiocoma examined. The arm spines on more distal segments increase in number in a relatively consistent manner for each species.

The identity of Ophiocoma macroplaca and its separation from the sympatric O. erinaceus in the Hawaiian Islands were determined in part by the use of the

arm spine sequence. O. macroplaca was originally described in the genus Ophiacantha by H. L. Clark

(1915) on the basis of a single, small (d.d. 2 mm) specimen. In 1949, A. H. Clark transferred the species

to Ophiomastix asperula on the basis of the few

scattered elongate granules noted on the disc of the

original specimen. My own examination of the typespecimen (MCZ 3700) and comparison with additional specimens of Ophiocoma collected in the

Hawaiian Islands indicated that disc granules alone are

typical of macroplaca and that it is a member of the

genus Ophiocoma in the SCOLOPENDRINA group. A

comparison of the arm spine sequences over the size

ranges of erinaceus and macroplaca illustrates one

method for distinguishing the two species (see Table

5). The regular presence of four spines on the third

segment for macroplaca and three spines on the third

segment for erinaceus is characteristic. The alternation

of the arm spines for both species as characteristic of

the group is indicated by the diagonal lines in

Table 5.

The arm spine sequence was instrumental in proving

that records of Ophiocoma scolopendrina from the

Hawaiian Islands are erroneous. Examination of the

specimens recorded as scolopendrina by A. H. Clark

(1949, pp. 52-53) from the 1902 Albatross stations

around the Hawaiian Islands shows that all but two

(USNM E7089 and E7088 are close to Ophiacantha

bisquamata Matsumoto) should be referred to macroplaca. Moreover, the specimen listed by Ely (1942,

p. 52) and described by H. L. Clark as scolopendrina

from Maui (MCZ 4515) has been reexamined and

also found to be macroplaca. The following characteristics separate the two taxa:
NUMBER 51 35

1. macroplaca: 4 arm spines on each side of segment 3.

scolopendrina: 3 spines on each side of segment 3.

2. macroplaca: ratio of upper arm spine length to aboral

arm plate length (for segment 10) 3.5-4.1:1 (X=3.4:1)

(N=28).

scolopendrina: ratio, 2.2-2.5 : 1(X = 2.4 : 1)(N=23).

3. macroplaca: oral arm plate with distal margin broadly

rounded, not concave, and lateral margins flared distally

at outer edges.

scolopendrina: oral arm plate with distal margin broadly

truncated, sometimes concave; lateral margins not

flared distally at outer edges.

4. macroplaca: Two tentacle scales present on specimens

larger than 2 mm (d.d.) and increasing regularly on

more segments with growth.

scolopendrina: One or two tentacle scales, only a few

proximal segments with two scales on specimens less than

10 mm (d.d.) ; frequently irregular number on distal

segments with growth.

In addition to morphological criteria, macroplaca

and scolopendrina are differentiated ecologically. Several workers (H. L. Clark, 1921; Murakami, 1938;

Balinsky, 1957; Ailsa M. Clark, 1952; Magnus, 1962,

1964; Shiino, 1964) have given accounts of the restricted littoral habitat of scolopendrina. In contrast,

O. macraplaca has only once been collected in the littoral zone (H. L. Clark, 1915) and is much more

common in depths between 5 and 100 meters.

The specimens listed by Koehler (1907a) as

Ophiocoma scolopendrina from "iles Sandwich" are

deposited in the Museum d'Histoire Naturelle de Paris

but cannot be located (Dr. Cherbonnier, personal

communication), and their determination remains

suspect until verification can be made. Likewise, the

species described as Ophiocoma variabilis by Grube

(1857) from Hawaii (Insel Woahu = Oahu) suggests

that this species is probably conspecific with scolopendrina and that there must have been a mistake in

the locality record. With reference to the arm spines,

Grube later stated: "mit Ausnahme der ersten 3, im

Bereich der Scheibe befindlichen Facher meist ze je 4,

dort nur zu je 3" (Grube, 1860, p. 32), which implies

that the first three segments have only three arm

spines. It has been shown above that Hawaiian specimens of macroplaca carry four spines on the third segment. In addition, Grube's description of the relative

length of the upper arm spine comes closer to that

noted for scolopendrina, and the pigmentation also is

similar to that known for this species. Unfortunately,

no examination of Grube's specimens has been possible because the whereabouts of the types originally

deposited in the Tartu Museum cannot be confirmed.

The arm spine sequence was also instrumental in

confirming Lutken's (1856, p. 2; 1859, p. 245) and

Martens' (1870, p. 251) suspicions that Ophiocoma

riisei is indeed a junior synonym for O. wendti described by Miiller and Troschel in 1842.6

 An examination of the type of O. wendti (ZMB 929) showed the

presence of only two arm spines on each side of the

first arm segment, a characteristic of this West Indian

species alone among other species in the SCOLOPENDRINA group. Indo-Pacific records of O. wendti

refer to several different taxa and are considered in

more detail below.

The erroneous records of O. wendti from the IndoPacific have been shown in part by an examination

of specimens Koehler (1922) described as this species:

six specimens from Samoa (USNM E4890) and one

specimen from the Philippines (USNM 40948) represent O. erinaceus (schoenleini form) and O. scolopendrina, respectively. Koehler's (1905, 1927) records

of this species from Indonesia and the Fiji Islands appear to represent the same polymorphic form of O.

erinaceus, based on the descriptions and my compariFIOURE 49.—Ophiocoma anaglyptica; upper arm spines.

* Ljungman (1872, p. 615) correctly considered some West

Indian material as Ophiocoma wendti, following Martens'

suggestion.
36 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE 5.—Arm spine sequence of Ophiocoma macroplaca and O. erinaceus

Ophiocoma

macroplaca ARM SPINE SEQUENCE

18 19 20 21 22 23 24 25 30 35 40 45 50

segment number

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 30 35 40 45 50 55 60 65 70 80

segment number

3 LZZ14 ^M 5

TZZ1 3-4 Z H 4-6 gggj 5-6

number of arm spines
NUMBER 5 1 37

son of similar specimens from those localities. H. L.

Clark (1938, p. 336) probably was correct in his assumption that Koehler's (1907b) record of O. wendti

from Shark Bay, Western Australia, is conspecific with

O. occidentalis. I have examined a specimen (ZMB

4559) labeled O. wendti from the same locality and it

conforms closely with O. occidentalis. Boone's (1938)

record of wendti from the Hawaiian Islands is certainly

in error, as her description and photographs strongly

indicate O. erinaceus. The color, large number of arm

segments with two tentacle scales, and arm spine

sequence point to this. In addition, the specimens

(ZMB 7076) reported by Hertz (1927, p. 118) as

wendti from the Seychelles have been reexamined. The

presence of three arm spines on the first segment

together with other differences show that these specimens are not wendti but are examples of scolopendrina.

Several lines of evidence, however, suggest that another species from the Indo-Pacific (perhaps in the

genus Ophiomastix) also has been mistakenly named

Ophiocoma wendti. Koehler (1907a, pi. 13, fig. 38)

described and illustrated a specimen with enlarged

claviform arm spines that were distinctly annulated.

The disc cover revealed coarse granules. H. L. Clark

(1921, pp. 129, 134) reported a similar specimen under

the name wendti from Zanzibar. That specimen (MCZ

1795), with a disc diameter of 25 mm, combines the

characters of Ophiocoma in the nature of the disc

granules with those of Ophiomastix in the nature of

the arm spines. Ailsa M. Clark reports (personal communication) that the British Museum has two specimens from Zanzibar that also fit this description.

Since Koehler's (1907a) material with the claviform

arm spines could be from the same locality, it is possible

that it does repesent a new taxon. It remains for more

specimens, especially smaller individuals, to be examined before a satisfactory taxonomic decision can be

reached.

Each of the species in the SCOLOPENDRINA group appears to develop the disc granules at a characteristic

size. Those species and the mimimum disc diameters at

which granules have been observed are as follows:

O. aethiops:

O. anaglyptica:

O. echinata:

O. erinaceus:

5.5 mm

4.5 mm

2.3 mm

7.5 mm

O. macroplaca: 2.0 mm

O. scolopendrina: 2.5 mm

O. wendti: 7.5 mm

This feature offers one method by which young specimens in the group can be identified, and it is especially

helpful where closely related species may be collected

FIGURE 50.—Ophiomastix annulosa; proximal view of arm

segment (d.d. 19 mm).

together (for example, O. echinata and O. wendti; and

O. erinaceus and O. scolopendrina or O. macroplaca).

Martens (1870) described Ophiocoma alternans

from the Philippines, based on a small specimen which

subsequently has been considered a synonym of O. scolopendrina (H. L. Clark, 1921, p. 121). The species described by Endean (1963) as Ophiocoma alternans becomes a junior homonym, and a new name will have

to be given for this Australian species. An apparently

well-defined geographic boundary seems to separate

Endean's species from northern relatives at the Great

Barrier Reef. It is difficult to judge the merit of several

qualitative differences used by Endean to separate his

species from O. erinaceus or O. occidentalis, but the

extension of the disc granules to the oral shield apparently is the best character for separating O. "alternans" from those two species. Examination of three

paratypes of "alternans" deposited in the Allan Hancock Foundation (AHF 797.1) also indicates that the

pigmentation as reported by Endean differs from

erinaceus.
38 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Variation in several morphological characters has led

some workers to consider some examples of Ophiocoma

erinaceus as representing more than a single species.

For example, Ophiocoma schoenleini Mtiller and Troschel, 1842, has been distinguished from O. erinaceus

primarily by having only one tentacle scale, relatively

shorter upper arm spines, and a different pattern of

disc granulation. Over a limited range in the IndoPacific, both this form and that with two tentacle

scales (typical erinaceus) have been collected together.

Both forms have been reported by Matsumoto (1917)

from the Ryukyu Islands and Formosa, by H. L. Clark

(1921) from Amboina and Torres Strait, by A. H.

Clark (1954) from Fiji, Samoa, and the Gilbert Islands,7

 by H. L. Clark. (1921, 1946) and Endean

(1957) from several localities along the Great Barrier

Reef, and by Domantay and Domantay (1966) from

the Philippines.

Specimens of both forms, from syntopic collecting

sites, have been examined from the Philippines, Torres

Strait, Fiji, and Samoa. These have been compared

with the type-specimen of O. schoenleini (ZMB 930).

In addition to the difference in the number of tentacle

scales, the two forms show several contrasting characters, but these overlap to a variable extent in some specimens from the same locality. A comparison of contrasting characters usually associated with each of the

two forms is presented below. Data are based on specimens from 8 to 20 mm (d.d.).

Specimens with two Specimens with one

tentacle scales (N=22) tentacle scale (N=39)

1. Four arm spines most 1. Three arm spines most

often on fourth seg- often on fourth segment, ment.

2. Maximum arm spin e 2. Maximum arm spin e

length to breadth of length to breadth of

oral plate (tenth free oral plate (tenth free

arm segment), X=2.2: arm segment), X=2.8:

1; range, 1.9 to 2.6:1. 1; range, 2.3 to 3.2:1.

3. Disc granules less often 3. Disc granules more often

extending into oral in- extending into oral interradius of disc. terradius of disc.

There appeared to be no difference in the pigmentation

of the two forms examined, and on both forms the disc

granules were not noted in specimens of less than 7.5

mm (d.d.).

7

 The specimens reported from the Gilbert Islands (USNM

E8061) have been reexamined and found to be O. scolopendrina.

The syntopic occurrence of both the one-scale and

two-scale forms in certain parts of the central IndoPacific and the presence of some specimens with characters (listed above) which were intermediate or mixed

between the two forms suggest that we are dealing

with polymorphs of the same species having phenotypically linked morphological characters. In the Indian

Ocean and eastern part of the Pacific only the form

of O. erinaceus having two tentacle scales is known.

Literature Cited

Agassiz, Louis

1836. Prodrome d'une Monographic des Radiaires ou

Echinodermes. Memoires de la Societe des Sciences

naturelles de Neuchatel, 1:168-199.

Balinsky, J. B.

1957. The Ophiuroidea of Inhaca Island. Annals of the

Natal Museum, 14(1): 1-35.

Blainville, H. M. D. de

1834. Manuel d'actinologie ou zoophytologie. Paris. 243

pages.

Boone, Lee

1938. The Marine Algae, Coelenterata, Annelida Polychaeta, Echinodermata, Crustacea, and Mollusca of

the World Cruises of Yachts Ara, 1928-1929, and

Alva, 1931-1932, .4 foa Mediterranean Cruise, 1933,

and Alva South American Cruise, 1933, William K.

Vanderbilt, Commanding. Part IV. Echinodermata.

Bulletin of the Vanderbilt Marine Museum, 7:115-

193.

Brock, J.

1888. Die Ophiuridenfauna des indischen Archipels.

Zeitschrift fur wissenschaftliche Zoologie, 47:465—

539.

Clark, Austin H.

1939. Echinoderms (Other than Holothurians) Collected

on the Presidential Cruise of 1938. Smithsonian

Miscellaneous Collections, 98(11) : 1—18.

1949. Ophiuroidea of the Hawaiian Islands. Bernice P.

Bishop Museum Bulletin, 195:1-133.

1952. Echinoderms from the Marshall Islands. Proceedings of the United States National Museum, 102:

265-303.

1954. Records of Indopacific Echinoderms. Pacific Science, 8(3): 243-263.

Clark, Ailsa M.

1952. The "Manihini" Expedition to the Gulf of Aqaba,

1948-1949. VII. Echinodermata. Bulletin of the

British Museum (Natural History) Zoology, 1:203—

214.

1966. Port Phillip Survey 1957-1963. Echinodermata.

Memoirs of the National Museum, Melbourne

(Victoria), 27:289-355 (with Station data in

Table A, pp. 377-384, and Charts 1, 2 at end of

volume).
NUMBER 51 39

1967. Echinoderms from the Red Sea. Part 2. (Crinoids,

Ophiuroids, Echinoids, and more Asteroids). Sea

Fisheries Research Station Israel Bulletin, 41:26—

58.

Clark, Hubert Lyman

1909. Scientific Results of the Trawling expedition of

H.M.C.S. Thetis off the Coast of New South Wales,

in February and March, 1898. Echinodermata.

Memoirs of the Australia Museum 4(11 ) :519-564 .

1915. Catalogue of Recent Ophiurans Based on the Collection of the Museum of Comparative Zoology.

Memoirs of the Museum of Comparative Zoology

at Harvard, 25(4): 165-376.

1917. Reports on the Scientific Results of the Albatross

Expedition to the Tropical Pacific, 1899-1900

(Part 18). Reports on the Scientific Results of the

Albatross Expedition to the Eastern Tropical Pacific, 1904-1905 (Part 30). Ophiuroidea. Bulletin

of the Museum of Comparative Zoology at Harvard,

61(12):428-453.

1921. The Echinoderm Fauna of Torres Strait: Its Composition and Its Origin. Carnegie Institution of

Washington Publication, 294:1-223.

1928. The Sea Lilies, Sea Stars, Brittlestars, and SeaUrchins of the South Australian Museum. Records

of the South Australian Museum, 3(4) :361-482.

1932. Echinodermata, other than Asteroids. Scientific Reports, Great Barrier Reef Expedition 1928-1929,

4(7):197-239.

1938. Echinoderms from Australia, an Account of Collections Made in 1929 and 1932. Memoirs of the

Museum of Comparative Zoology at Harvard, 55:

1-596.

1939. Ophiuroidea. Scientific Reports, the John Murray

Expedition, 1933-1934, 6(2):29-136 .

1946. The Echinoderm Fauna of Australia, Its Composition and Its Origin. Carnegie Institution of Washington Publication, 566:1-567.

Dakin, William J.; Isobel Bennett; and Elizabeth Pope

1960. Austrian Seashores. Revised edition, 372 pages. Sydney: Angus and Robertson.

Downey, Maureen E.

1969. Catalog of Recent Ophiuroid Type Specimens in

Major Collections in the United States. United

States National Museum Bulletin, 293:1-239.

Domantay, Jose, and Cecilia R. Domantay

1966. Studies on the Classification and Distribution of

Philippine Littoral Ophiuroidea (Brittle Stars).

Philippine Journal of Science, 95(1) : 1-76 .

Duchassaing, P.

1850. Annimaux radiaires des Antilles. 33 pages. Paris:

J. B. Bailliere et Fils.

Ely, Charles A.

1942. Shallow-Water Asteroidea and Ophiuroidea of

Hawaii. Bernice P. Bishop Museum Bulletin,

176:1-63.

1944. A New Brittle-Star (Ophiocoma anaglyptica)

from Canton Island. Journal of the Washington

Academy of Sciences, 34(11) : 373-375.

Endean, R.

1957. The Biogeography of Queensland's Shallow-Water

Echinoderm Fauna (Excluding Crinoidea) with

a Rearrangement of the Faunistic Provinces of

Tropical Australia. Australian Journal of Marine

and Freshwater Research, 8(3) : 233-273.

1963. A New Species of Brittle-Star (Echinodermata,

Ophiuroidea) from Northern New South Wales.

Proceedings of the Linnean Society of New South

Wales, 88(3): 295-297.

Farquhar, H.

1908. Description of a New Ophiuroid. Transactions and

Proceedings of the New Zealand Institute, 40:108.

Fell, H. Barraclough

1949a. New Zealand Littoral Ophiuroids. Turatara, 2(3) :

121-129.

1949b. The Constitution and Relations of the New Zealand

Echinoderm Fauna. Transactions of the Royal

Society of New Zealand, 77(5) :208-212.

1952. Echinoderms from Southern New Zealand. Zoology

Publications from Victoria University of Wellington, 18:1-37.

1958. Deep-Sea Echinoderms of New Zealand. Zoology

Publications from Victoria University of Wellington, 24:1-40.

1962. Native Sea-Stars. 64 pages. Wellington: A. H. and

A. W. Reed Ltd.

Forbes, Edward

1841. A History of British Starfishes and Other Animals

of the Class Echinodermata. 267 pages. London:

John Van Voorst.

Graham, John

1962. The North Otago Shelf Fauna. Part II. Echinodermata. Transactions of the Royal Society of New

Zealand, Zoology, 2(23): 199-202.

Grave, Caswell

1898. Embryology of Ophicoma echinata, Agassiz. Preliminary Note. The Johns Hopkins University Circulars, 18:6-7.

Grube, A. E.

1857. Diagnosen einigen neuen Echinodermen. Archiv

fiir Naturgeschichte, 23:340-344.

1860. Beschreibungen neuer oder weniger bekannter

Seesterne und Seeigel. Nova acta Academic

Caesareae Leopoldino Caroline germanicae naturae

curiosorum, 27:1—50.

Hertz, Mathilde

1927. Die Ophiuroiden der Deutschen Tiefsee-Expedition.

I. Chilophiurida Matsumoto (Ophiolepididae,

Ophioleucidae, Ophiodermatidae, Ophiocomidae).

In, C. Chun, editor, Wissenschaftliche Ergebnisse

der Deutschen Tiefsee-Expedition auf dem Dampfer

Valdivia, 1898-1899, volume 22, part 3, pages

59-122.

Hurley, D. E.

1959. Some Features of the Benthic Environment in Cook

Strait. New Zealand Journal of Science, 2:137-147.
40 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Koehler, Rene

1898. Echinodermes recueillis par VInvestigator dans

l'Ocean Indien. II. Les Ophiures Httorales. Bulletin

Scientifique de la France et de la Belgique, 31:54-

124.

1904. Ophiures nouvelles ou peu connues. Memoires de la

Societe Zoologique de France, 17 :54—119.

1905. Ophiures de l'Expedition du Siboga. Partie 2.

Ophiures Httorales. In, M. C. W. Weber, SibogaExpedie . . . 1899-1900, monograph 45b, pages

1-142.

1907a. Revision de la collection des Ophiures du Museum

d'Histoire naturelle de Paris. Bulletin Scientifique

de la France et de la Belgique, 41: 79-351.

1907b. Die Fauna Siidwest-Australiens, Ophiuroidea.

Ergebnisse der Hamburger siidwest-australischen

Forschungsreise 1905, 1 (4): 241-254.

1922. Ophiurans of the Philippine Seas and Adjacent

Waters. United States National Museum Bulletin,

100(5):1-480.

1924. Les Echinodermes des mers d'Europe. Volume 1,

362 pages. Paris: Gaston Doin et Co.

1927. Ophiures recueillis aux lies Gilbert, Marshall, et

Fiji. Goteborgs K. Vetenskaps-och vitterhessamhalles handlingar, Serie 4, 33(3) : 1-13.

1931. Ophiures recueillis par le Dr. Th. Mortensen dan

les mers d'Australie et dans l'Archipel Malais.

Videnskabelige Meddelelser fra Dansk naturhistoriske Forening i Kjobenhavn, 89:1-295.

Lamarck, Jean B. P. A. de

1816. Histoire naturelle des animaux sans vertebres. Volume 2 (1st edition), 568 pages. Paris: Verdiere.

Ljungman, Axel V.

1872. Forteckning ofver uti Vestindien af Dr. A. Goes

samt under korvetten Josefinas espedition i Atlantiska Oceanen samlade Ophiurider. Ofversigt af

Kongel. Vetenskaps-Akademiens Fbrhandlingar,

1871(6):615-657.

Loriol, P. de

1894. Catalogue raisonne des Echinodermes recueillis par

M. V. de Robillard a 1'Ile Maurice. III. Ophiurides, Astrophytides et Crinoides. Memoires de la

Societe de Physique et d'Histoire Naturelle de

Geneve, 32(1):1-64.

1899. Notes pour servir a l'histoire des Echinodermes.

VII. Memoires de la Societe de Physique et d'Histoire Naturelle de Geneve, 33(1): 1-34.

Lutken, C. F.

1856. Bid rag til Kundskab om Slangestjernerne. 3. Bidrag

til Kundskab om Ophiurerne ved Central-Amerikas

Vestkyst. Videnskabelige Meddelelser fra den naturhistoriske Forening i Kjobenhavn, 1856, 1-2:

20-26.

1859. Additamenta ad historiam Ophiuridarum. Beskrivelser af nye eller hidtil kun ufuldstacndigt kjendte

Arter af Slangestjerner. Anden Afdeling. Det Kongelige Danske Videnskabernes Selskab Skrifter,

naturvidenskabelig og mathematisk Afdeling, series

5,5:177-271.

1869. Additamenta ad historiam Ophiuridarum. Beskrivende og kritiske Bidrag til Kundskab om Slangestjerner. Tredie Afdeling. Det Kongelige Danske

Videnskabernes Selskab Skrifter, naturvidenskabelig

og mathematisk Afdeling, series 5, 8: 24-109.

Lyman, Theodore

1860. Description of New Ophiuridae, Belonging to the

Smithsonian Institution and to the Museum of

Comparative Zoology at Cambridge. Proceedings of

the Boston Society of Natural History, 7:252-262.

1861. Descriptions of New Ophiuridae. Proceedings of the

Boston Society of Natural History, 8:75—86.

1865. Ophiuridae and Astrophytidae. Memoires of the

Museum of Comparative Zoology at Harvard,

1(1):1-200.

1872. Note sur les Ophiurides et Euryales qui se trouvent

dans les collections du Museum d'Histoire Naturelle de Paris. Annales Sciences Naturelles, Zoologie et Paleontologie, series 5, 16(4): 1-8.

1874. Ophiuridae and Astrophytidae, New and Old.

Bulletin of the Museum of Comparative Zoology

at Harvard, 3(10) :221-272.

1882. Report of the Ophiuroidea Dredged by H.M.S.

Challenger, 1873-1876. Challenger Reports, Zoology, 5(14):1-386.

McKnight, D. G.

1967. Additions to the Echinoderm Fauna of the Chatham Rise. New Zealand Journal of Marine and

Freshwater Research, 1 (3): 291-313.

Magnus, Dietrich E. B.

1962. Uber das "Abwieden" der Flutwasseroberflach

durch den Schlangenstem, Ophiocoma scolopendrina (Lamarck). Verhandlungen der Deutschen

Zoologischen Gesellschaft in Jena, 62:471-481.

1964. Gezeitenstromung und Nahrungsfiltration bei

Ophiuren und Crinoiden. Helgolander wissenschaftliche Merresunterseeische, 10 (1-4): 104-117.

Marktanner-Turneretscher, G.

1887. Beschreibung neuer Ophiuriden und Bemerkungen

zu bekannten. Annalen des K.K. Naturhistorischen

H of museums, 2:291-316.

Martens, E. von

1870. Die Ophiuriden des indischen Oceans. Archiv fur

Naturgeschichte, 36:244-263.

Matsumoto, Hikoshichiro

1917. A Monograph of Japanese Ophiuroidea, Arranged

According to a New Classification. Journal of the

College of Science, Imperial University of Tokyo,

38(2):1-408.

Mortensen, Th.

1920. Notes on some Scandinavian Echinoderms with

Descriptions of Two New Ophiuroids. Videnskabelige Meddelelser fra Dansk naturhistoriske Forening

i Kjobenhavn, 72:45-79.

1921. Studies of the Development and Larval Forms of

Echinoderms. 261 pages. Copenhagen: G. E. C.

Gad.
NUMBER 5 1 41

1924. Papers from Dr. Th. Mortensen's Pacific Expedition, 1914-1916. XX. Echinoderms of New Zealand

and Auckland-Campbell Islands. II. Ophiuroidea.

Videnskabelige Meddelelser fra Dansk naturhistoriske Forening i Kjobenhavn, 77:91-177.

1931. Contributions to the Study of the Development and

Larval Forms of Echinoderms. Volumes 1, 2. Det

Kongelige Danske Videnskabernes Selskab Skrifter,

naturvidenskabelig og mathematisk Afdeling, series

9,4:1-39.

1936. Echinoidea and Ophiuroidea. In Discovery Reports,

12:199-348.

1937. /Contribution to the Study of the Development and

Larval Forms of Echinoderms. Volume 3. Det

Kongelige Danske Videnskabernes Selskab Skrifter,

naturvidenskabelig og mathematisk Afdeling, series

9, 7(3):1-65.

Miiller, Johannes, and Franz Herrmann Troschel

1842. System der Asteriden. 134 pages. Braunschweig:

F. Vieweg und Sohn.

Murakami, Shiro

1938. A Curious Habit of Ophiocoma scolopendrina (Lamarck). [In Japanese.] Kagaku Nanyo, 1(20):

40-41.

1943a. Report on the Ophiurans of Palau, Carolina Islands. Journal of the Department of Agrieulture,

Kyusyu Imperial University, 7(4): 159-204.

1943b. Report on the Ophiurans of Yaeyama, Ryukyu.

Journal of the Department of Agriculture, Kyusyu

Imperial University, 7(5) : 205-219.

1963. The Dental and Oral Plates of Ophiuroidea. Transactions of the Royal Society of New Zealand, Zoology, 4(1):1-48.

Parslow, Rosemary E., and Ailsa M. Clark

1963. Ophiuroidea of the Lesser Antilles. Studies on the

Fauna of Curacao and other Caribbean Islands,

15:24-50.

Pawson, David L.

1965. New Records of Echinoderms from the Snares Islands to the South of New Zealand. Transactions of

the Royal Society of New Zealand, Zoology, 6(25) :

253-260.

Peters, Wilhelm

1851. Uebersicht der von ihm an der Kiiste von Mossambique eingesammelten Ophiuren, unter denen sich

zwei neue Gattungen befinden. Koniglich Akademie

der wissenschaften, Berlin, Bericht, 1851, pages

463-466.

Pfeffer, Georg

1900. Echinodermen von Ternate. Echiniden, Asteriden,

Ophiuriden, und Comatuliden. Abhandlungen

herausgegeben von der Senckenbergischen naturforschenden Gesellschaft, 25:81-86.

Shiino, Sueo M.

1964. Results of Amami Expedition. 1. General Remarks.

University of Mie Report of the Faculty of Fisheries, 5(1):145-152.

Smith, Edgar A.

1876. Descriptions of Two New Species of Ophiocoma.

Annals and Magazine of Natural History, series 4,

18(l):39-40.

1879. Transit of Venus Expeditions, 1874—75. Collections

from Rodriguez Island. Mollusca (Echinodermata).

Philosophical Transactions of the Royal Society of

London, 168 (extra volume): 473-484, 564-568.

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