The Echinoderm Fauna 

of Ascension Island, 

South Atlantic Ocean 

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SMITHSONIAN CONTRIBUTIONS TO THE MARINE SCIENCES • NUMBER 2 

The Echinoderm Fauna 

of Ascension Island, 

South Atlantic Ocean 

David L. Pawson 

SMITHSONIAN INSTITUTION PRESS 

City of Washington 

1978 
ABSTRAC T 

Pawson, David L. The Echinoderm Fauna of Ascension Island, South Atlantic 

Ocean. Smithsonian Contributions to the Marine Sciences, number 2, 31 pages, 

11 figures, 1978.—Two recent intertidal collecting expeditions and existing 

museum collections have added much to knowledge of the Ascension Island 

echinoderm fauna. Twenty-five species are now known from Ascension; eight are 

new records. One new species, Holothuria (Halodeima) manningi, and one new 

subspecies, Echinometra lucunter polypora, are described. Diadema ascensionis 

Mortensen is regarded as a subspecies of D. antillarum Philippi, and Pseudoboletia atlantica H. L. Clark is regarded as a subspecies of P. maculata Troschel. 

T he echinoderm fauna of Ascension Island includes 8 amphi-Atlantic species, 

3 western Atlantic species, 4 eastern Atlantic species, 5 circumtropical species, 

4 species shared only with St. Helena, and 1 endemic species. There are in addition three endemic subspecies. Twelve species are shared with St. Helena, and 

both islands are closely similar in terms of numbers and relationships of their 

faunal components. Colonization of both islands by planktonic larval stages is 

suggested. Dendrochirotid holothurians, which lack such larval stages, are not 

represented at either St. Helena or Ascension. The structure of the Ascension 

fauna seems to have been determined by vagaries of ocean surface and subsurface currents. In contrast, Bermuda, which sits astride the Gulf Stream, has 

a fauna that is entirely typical of the West Indian region to the south. 

OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded 

in the Institution's annual report, Smithsonian Year. SERIES COVER DESICN: Seascape along the 

Atlantic coast. 

Library of Congress Cataloging in Publication Data 

Pawson, David Leo, 1938-

The Echinoderm fauna of Ascension Island, South Atlantic Ocean. 

(Smithsonian contributions to the marine sciences ; 2) 

Bibliography: p. 

1. Echinodermata—Ascension Island (Atlantic Ocean) I. Title. II. Series. 

QL383.35.A8P38 593'.9 77-20941 
Contents 

Page 

Introduction 1 

Previous Records of Echinoderms from Ascension 2 

Checklist of Ascension Island Echinoderms 4 

Composition of the Ascension Echinoderm Fauna 4 

Relationships of the Ascension Echinoderm Fauna 4 

How "Isolated" Is Ascension? 6 

Material Examined 8 

Class STELLEROIDEA 9 

Subclass ASTEROIDEA 9 

Order PAXILLOSIDA 9 

Family ASTROPECTINIDAE 9 

Tethyaster magnificus (Bell) 9 

Order VALVATIDA 9 

Family CHAETASTERIDAE 9 

Chaetaster longipes (Retzius) 9 

Family OPHIDIASTERIDAE 10 

Ophidiaster guildingi Gray 10 

Linckia guildingi Gray 10 

Subclass OPHIUROIDEA 1 

Order OPHIURIDA 1 

Family OPHIACTIDAE 1 

Ophiactis savignyi (Miiller and Troschel) 1 

Ophiactis lymani Ljungman 1 

Family AMPHIURIDAE 1 

Amphiura capensis Lyman 1 

Ophiostigma abnorme (Lyman) L 

Family OPHIOTHRICIDAE 12 

Ophiothrix (Ophiothrix) roseocaerulans Grube 12 

Class ECHINOIDEA 12 

Order CIDAROIDA 12 

Family CIDARIDAE 12 

Eucidaris clavata Mortensen 12 

Tretocidaris spinosa Mortensen 16 

Order DIADEMATOIDA 17 

Family DIADEMATIDAE 17 

Diadema antillarum ascensionis Mortensen 17 

Order ARBACIOIDA 17 

Family ARBACIIDAE 17 

fCoelopleurus floridanus Agassiz 17 

Order TEMNOPLEUROIDA 17 

Family TOXOPNEUSTIDAE 17 

Pseudoboletia maculata atlantica Clark 17 

iii 
SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Page 

Tripneustes ventricosus (Lamarck) 20 

Order ECHINOIDA 20 

Family ECHINOMETRIDAE 20 

Echinometra lucunter polypora, new subspecies 20 

Echinometra Specimens 22 

Summary of Echinometra Morphometric Data 22 

Order HOLECTYPOIDA 23 

Family ECHINONEIDAE 23 

Echinoneus cyclostomus Leske 23 

Order CLYPEASTEROIDA 23 

Family ROTULIDAE 23 

Heliophora orbiculus (Linnaeus) 23 

Order SPATANGOIDA 24 

Family BRISSIDAE 24 

Brissus unicolor (Leske) 24 

Class HOLOTHUROIDEA 24 

Order ASPIDOCHIROTIDA 24 

Family HOLOTHURIIDAE 24 

Holothuria (Halodeima) grisea Selenka 24 

Holothuria (Halodeima) manningi, new species 26 

Holothuria (Thymiosycia) arenicola Semper 27 

Holothuria (Platyperona) sanctori Delle Chiaje 27 

Family STICHOPODIDAE 27 

Isostichopus badionotus (Selenka) 27 

Order APODIDA 28 

Family SYNAPTIDAE 28 

Euapta lappa (Muller) 28 

Literature Cited 29 
The Echinoderm Fauna 

of Ascension Island, 

South Atlantic Ocean 

David L. Pawson 

Introduction 

Ascension Island lies in the South Atlantic at 

07°57'S, 14°22W, approximately 150 kilometers 

west of the centerline of the mid-Atlantic Ridge 

(Wilson, 1963). It is an entirely volcanic island, 

comprising the uppermost part of a cone which 

rises from a depth of about 3000 meters below sea 

level (Atkins et al., 1964). Daly (1925) has noted that 

the only nonvolcanic material on the island are 

"some small patches of beach material thrown up 

by storm waves." Much of this material is calcareous, 

derived from calcareous algae and mollusk shells. 

The island is approximately circular, with an area 

of about 97 square kilometers (Figure 1). In the 

absence of fossils and other reliable indicators, it is 

difficult to determine the length of time that Ascension has stood above sea level. Estimates range from 

approximately 1.5 million years to considerably less 

than 1 million years (Sullivan, 1974; Daly, 1922; 

J. D. Bell (in litt.) in Chace and Manning, 1972). 

The nearest large land masses are a considerable 

distance away; the coast of Brazil lies 2200 km to 

the west, West Africa is 1300 km to the northeast 

(Figure 2). To the south, 1100 km away, lies St. 

Helena, another volcanic island, but considerably 

older (20 million years; Wilson, 1963) than Ascension. 

David L. Pawson, Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, 

Washington, D.C. 20560. 

Until very recently, no extensive collections of 

invertebrates have been made at Ascension, and 

our knowledge of the echinoderm fauna stems from 

one or two small collections made during the late 

1800s, and visits by Antarctic research vessels during 

the first half of this century. Dr. R. B. Manning, 

National Museum of Natural History, visited Ascension in 1971 and made extensive collections of invertebrates. The interesting material obtained led 

to the organization of a second Smithsonian expedition in 1976. This paper is based upon material 

collected during those two expeditions: Asc. = collection stations for 1976 expedition; RBM = collection stations for 1971 expedition; USNM — catalog numbers using abbreviation for former United 

States National Museum, collections of which are 

in the National Museum of Natural History, Smithsonian Institution. 

ACKNOWLEDGMENTS.—I am grateful to Dr. R. B. 

Manning for making a fine collection of echinoderms at Ascension in 1971. A second expedition to 

the island in 1976 by Dr. Manning, Dr. M. L. 

Jones, Dr. J. Rosewater and myself, of the National 

Museum of Natural History, and Dr. A. J. Provenzano, Jr., of the Old Dominion University, Norfolk, resulted in the amassing of an extensive series 

of shallow water marine invertebrates, among them 

numerous echinoderms. Mr. Ross Simons of the 

Office of the Assistant Secretary for Science, Smithsonian Institution, was especially helpful in making 

necessary arrangements with the U.S. Air Force and 
SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

ENGLISH BAY 

NORTH EAST BAY 

FORT HAYES 

COLLYER POINT 

7

U

5 7 I S — 

MCARTHUR POINT 

TURTLE SHELL BEACH 

SOUTH WEST BAY 

SHELLY BEAC 

l a 52 w 

FICURE 1.—Outline map of Ascension Island, showing collecting localities. 

with the Administrator of Ascension Island. The 

Administrator, Mr. Jeffrey C. Guy, the U.S. base 

commanders Major Henry Spangler and Lieutenant 

Colonel Thomas Morris, and the head of the NASA 

tracking station, Mr. Jefferson Speck, were most 

helpful to us during our stay at Ascension. Our 

expenses were met by a grant from the Smithsonian's 

Fluid Research Fund; we are grateful to Mr. S. 

Dillon Ripley, Secretary of the Smithsonian Institution, for his support. 

For the loan of additional study material, I wish 

to thank Miss Ailsa M. Clark of the British Museum 

(Natural History), Dr. F. Jensenius Madsen, Universitetets Zoologiske Museum, Copenhagen, and 

Dr. Lowell P. Thomas, University of Miami. The 

photographs were made by Mr. V. Krantz, the maps 

and graphs by Irene Jewett. Miss Tamara A. Vance 

assisted with measurements of echinoids and collation of data. I thank Drs. M. L. Jones and R. B. 

Manning for reviewing the manuscript. Partial support for preparation of this paper was derived from 

a grant made by the Smithsonian Research Foundation (SRF 71500525). 

PREVIOUS RECORDS OF ECHINODERMS FROM ASCENSION 

The first record of an echinoderm from the island 

was that of Cuninghame (1699:298), who made the 

following observations: 

One small warted Barbadoes sea egg. Echinus ovarious Barbad, verrucis plurimis minoribus Mus. Petiver 123. 

T h e spines of these are purplish, especially the tips, the 

largest I have yet seen, exceed not a crow-quill in thickness, 

and are scarce an inch long; they end pointed, and are finely 

striated if strictly viewed. Th e naked shell of this was somewha t more than six inches in circumference, and about 5 

broadways and 5y2 lengthways. 

Bell (1881:437) suggested that this "small warted 

Barbadoes sea egg" was undoubtedly a specimen of 

Echinometra sub angular is Leske (= E. lucunter 

(Linnaeus)); Cunninghame's description fits that 

species admirably. In the same paper Bell listed the 

following species from Ascension Island: 

Bell's name 

Cidaris metularia Lamarck 

Diadema setosum Gray 

Tripneustes angulosus Leske 

Echinometra subangularis 

Leske 

Echinoneus cyclostomus Leske 

Rotula dentata Leske 

Linckia diplax Miiller and 

Troschel 

Currently accepted name 

Eucidaris clavata Mortensen 

Diadema antillarum 

ascensionis Mortensen 

Tripneustes ventricosus 

(Lamarck) 

Echiyxometra lucunter 

polypora Pawson 

Same 

Heliophora orbiculus 

(Linnaeus) 

Linckia guildingi Gray 
NUMBER 2 

FIGURE 2.—Central Atlantic Ocean, showing principal islands. 

During the early part of this century, several 

ships paused briefly at Ascension, when they were 

returning from expeditions in the southern oceans, 

and made collections, usually by dredging. Koehler 

(1908) reported the following species from Ascension, collected by the Scotia: 

Currently accepted name 

Tethyaster magniftcus (Bell) 

Koehler's name 

Moiraster magniftcus (Bell) 

Chaetaster longipes (Retzius) 

Amphiura capensis Lyman 

Tretocidaris spinosa 

Mortensen 

Cidaris minor, new species 

}Coelopleurus floridanus 

Agassiz 

Echinometra subangularis 

(Leske) 

Pseudoboletia maculata 

Troschel 

Same 

Same 

Same 

Eucidaris clavata Mortensen 

Same 

Echinometra lucunter 

polypora Pawson 

Pseudoboletia maculata 

atlantica Clark 

dema ascensionis Mortensen (now D. antillarum 

ascensionis) at Ascension, according to Mortensen 

(1909). 

As a result of a visit by the Discovery, Fisher 

(1940) noted the presence of Ophidiaster guildingii 

at Ascension, and Mortensen (1936) listed the following species: 

The Deutsche Sudpolar-Expedition collected DiaMortensen's name 

Ophiothrix roseocaerulans 

Grube 

Ophiactis savignyi (Muller 

and Troschel) 

Ophiostigma abnorme 

(Lyman) 

Eucidaris tribuloides 

(Lamarck) 

Diadema antillarum var. 

ascensionis Mortensen 

Echinometra lucunter 

(Linnaeus) 

Currently accepted name 

Same 

Same 

Same 

Eucidaris clavata Mortensen 

Diadema antillarum 

ascensionis Mortensen 

Echinometra lucunter 

polypora Pawson 
SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Thus, at the time of writing of this paper, 17 

species of echinoderms were known from Ascension. 

The following checklist lists all 25 known species 

in systematic order; new records are marked with an 

asterisk (*). 

ful (see p. 11). The single juvenile specimen of 

Coelopeurus recorded from Ascension was identified by Koehler (1908) as C. floridanus Agassiz; this 

identification must remain in doubt until adult 

specimens are found. 

CHECKLIST OF ASCENSION ISLAND ECHINODERMS 

CRINOIDEA 

None 

ASTEROIDEA 

Family OPHIOTHRICIDAE 

Tethyaster magniftcus (Bell) 

Family CHAETASTERIDAE 

Chaetaster longipes (Retzius) 

Family OPHIDIASTERIDAE 

Ophidiaster guildingi Gray 

Linckia guildingi Gray 

OPHIUROIDEA 

Family OPHIACTIDAE 

Ophiactis savignyi (Muller and Troschel) 

* Ophiactis lymani Ljungman 

Family AMPHIURIDAE 

7 Amphiura capensis Lyman 

Ophiostigma abnorme (Lyman) 

Family OPHIOTHRICIDAE 

Ophiothrix (Ophiothrix) roseocaerulans Grube 

ECHINOIDEA 

Family CIDARIDAE 

Eucidaris clavata Mortensen 

Tretocidaris spinosa Mortensen 

Family DIADEMATIDAE 

Diadema antillarum ascensionis Mortensen 

Family ARBACIIDAE 

?Coelopleurus floridanus Agassiz 

Family TOXOPNEUSTIDAE 

Pseudoboletia maculata atlantica H. L. Clark 

Tripneustes ventricosus (Lamarck) 

Family ECHINOMETRIDAE 

Echinometra lucunter polypora Pawson 

Family ECHINONEIDAE 

Echinoneus cyclostomus Leske 

Family ROTULIDAE 

Heliophora orbiculus (Linnaeus) 

Family BRISSIDAE 

*Brissus unicolor (Leske) 

HOLOTHUROIDEA 

Family HOLOTHURIIDAE 

*Holothuria (Halodeima) grisea Selenka 

^Holothuria (Halodeima) manning!, new species 

^Holothuria (Thymiosycia) arenicola Semper 

*Holothuria (Platyperona) sanctori Delle Chiaje 

Family STICHOPODIDAE 

*Isostichopus badionotus (Selenka) 

Family SYNAPTIDAE 

*Euapta lappa (Muller) 

The record of Amphiura capensis Lyman is doubtCOMPOSITION OF THE ASCENSION ECHINODERM FAUNA 

The fauna as it is known today comprises 25 

species (Table 1), of which one, Amphiura capensis, 

is a doubtful record. The identity of Coelopleurus 

floridanus has yet to be confirmed. Eight species are 

reported from Ascension for the first time, but only 

one of these, Holothuria manningi, is new. 

There are some notable absentees from the fauna. 

No members of the holothurian Order Dendrochirotida have yet been found, despite the fact that 

these "cucumaria-type" holothurians are common 

on both sides of the Atlantic Ocean (see below for 

discussion). No crinoids are known from Ascension. 

It is also surprising that many species that are 

amphi-Atlantic in distribution and can tolerate a 

variety of habitats are apparently absent from 

Ascension. These include such common shallowwater forms as Linckia bouvieri Perrier, Axiognathus 

squamatus (Delle Chiaje), Ophiocoma pumila 

Liitken, Ophioderma appressum (Say), and Ophiolepis paucispina (Say). 

RELATIONSHIPS OF THE ASCENSION ECHINODERM 

FAUNA 

As can be seen from Table 1, the relationships of 

the echinoderm fauna of Ascension are complex: 

8 species (32%) are amphi-Atlantic; 1 species (4%) 

is restricted to Ascension; 3 species (12%) are also 

known from the western Atlantic only; 4 species 

(16%) are also known from the eastern Atlantic 

only; 5 species (20%) are circumtropical in distribution; 4 species (16%) are also known from St. 

Helena only; 12 species (48%) are shared by Ascension and St. Helena. 

These figures are similar to those for the mollusks given by Rosewater (1975). The only notable 

difference lies in the fact that 5 of the 89 Ascension 

mollusk species (6%) occur at Ascension and St. 

Helena only, while 4 of the 25 echinoderms (16%) 

have this distribution pattern. There is some indication here that Ascension-St. Helena are more 
NUMBER 2 

TABLE 1.—Relationships of Ascension echinoderms (+ = present; O = present as species, but 

not as subspecies listed; ? = doubtful record) 

Ascension echinoderms 

Ascension 

Amphi-Atlantic 

Western 

Atlantic 

Eastern Atlantic 

Gosmopolitan- circumtropical 

St. Helena 

St. Helena and 

Ascension 

+ + 

+ + 

+ 

+ 

+ + 

+ + 

+ 

+ 

+ + 

+ + 

+ + 

o ? + 

+ ? 

o + + 

+ ? 

0 + + 

+ 

+ 

+ 

+ 

+ 

+ 

+ + 

+ 

+ + 

1 8 3 b 5 12 6 

"isolated" for the echinoderms than for the mollusks, but little weight can be attached to such 

slender evidence. 

T he relationships expressed in the above percentages imply that propagules have reached Ascension from the east and from the west. It seems 

likely that colonization of Ascension was mediated 

by surface and subsurface transport of planktonic 

larval stages. 

Briggs (1974) has pointed out that Ascension lies 

on the "northern limb of the South Atlantic gyre 

where the water movement is relatively rapid and 

the direction of flow almost due west." He notes 

that if this pattern of surface water flow were constant, then one would expect that for the fishes 

there would be a strong relationship with West 

Africa. But this is not so, and Briggs suspects that 

Ascension comes under the influence of the east-
SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

ward-flowing Equatorial Countercurrent for at least 

part of the year. 

The equatorial undercurrent, flowing eastward at 

velocities of around 0.8 to 2.9 knots (Metcalf et al., 

1962; Sturm and Voigt, 1966; Voigt, 1975), with a 

core which may range from the surface to (usually) 

around 75 meters, has been suggested by Chesher 

(1966) as a likely route for transportation of larvae 

of echinoids across the Atlantic from west to east, 

thereby maintaining genetic continuity between 

populations of amphi-Atlantic species. Chesher calculated that larvae might make the trans-Atlantic 

trip in a minimum of 43 days and a maximum of 

70 days. Scheltema (1968, 1971) suggested that the 

undercurrent would be a potent dispersal agent for 

his so-called teleplanic molluscan larvae. The true 

extent of the equatorial undercurrent is not known. 

Most authors estimate that it extends southwards to 

a latitude of around 2°S. Possibly then the current 

might not directly influence the fauna of Ascension, 

which lies at latitude 7°57/S, some 600 km away. 

Some alternative mechanisms for trans-Atlantic 

transport of pelagic larval stages have been discussed by Scheltema (1968, 1971) for the North 

Atlantic; similar patterns of current flow exist for 

the South Atlantic. For successful transport of larvae 

in the North or South Atlantic gyres, the larvae 

must be eurythermal and long-lived. Six of the ten 

mollusk species discussed by Scheltema in 1971 have 

larval lives of at least three months; two others can 

reach the settling state in less than two months; 

these two, plus the remaining two species, can 

probably delay metamorphosis until conditions are 

suitable for settlement. 

Regrettably, very little is known about the actual 

larval life span of echinoderms. The excellent investigations of Mortensen (1921, 1931, 1938) and 

others are mostly descriptive. 

For Ascension Island species, the following information is available. Linckia guildingi: In the 

related L. multifora the late brachiolaria stage is 

reached after 27 days (Mortensen, 1938); in L. 

laevigata metamorphosis can take place after 22 

days (Yamaguchi, 1973). Ophiactis savignyi: Late 

ophiopluteus is reached after 21 days (Mortensen, 

1931). Eucidaris clavata: In the closely related E. 

tribuloides metamorphosis takes place after about 

25 days (McPherson, 1968). Tripneustes ventricosus: 

Fully developed larva after 22 days (Mortensen, 

1921). Echinometra lucunter: Metamorphosis takes 

places after 19 days (Mortensen, 1921). Holothuria 

species: In H. impatiens metamorphosis can take 

place after 21 days, and in H. difficilis after 14 days 

(Mortensen, 1938). 

Devaney (1973) extracted estimates of average 

lengths of larval life for tropical echinoderms from 

Thorson (1946) as follows: 

Number of days 

0-9 

10-20 

21-30 

31-40 

41-50 

Percentage of species 

7 

33 

26 

17 

13 

While the figures given above provide some useful guidelines, it must always be borne in mind that 

metamorphosis can be delayed for considerable 

periods of time if proper food and/or proper substrate are not available, or if physical factors such 

as temperature and salinity are not optimal (Thorson, 1950). 

The fact that Ascension appears to have received 

colonists from the east and from the west leads to 

the suggestion that the important surface and subsurface currents mentioned above are not exerting 

a continuous influence on the island's fauna. Latitudinal shifts in currents accompanied by extensive 

midocean eddies (Robinson, 1976) over the past one 

million years have no doubt had important effects 

upon composition of the Ascension fauna. 

How "ISOLATED" IS ASCENSION? 

Oceanic islands are useful natural laboratories for 

investigation of effects of isolation upon their resident populations of animals and plants. MacArthur 

and Wilson (1967) noted that new populations 

arriving on an island might pass through three 

overlapping evolutionary phases. During the first 

phase, genetic divergence from the "mother" population might take place (founder effect: see Mayr, 

1963) because the colonizing population is small, 

and contains fewer genes than the "mother population" (the founder principle.) There is some experimental evidence in support of the founder principle (see MacArthur and Wilson, 1967) but some 

critics have suggested that many colonizations are 

made by successive waves of propagules, and that 

large fractions of the genetic variation of the mother 

population can be inserted into the founder popula-
NUMBER 2 

tion, thus reducing genetic drift to a low level. 

During the second phase, adjustments are made to 

the new environment. The third phase comprises 

speciation, secondary emigration, and radiation. 

It is assumed that Ascension has been available 

for colonization only within the past one million 

years or so. The Ascension fauna offers some excellent possibilities for exploration of the effects of 

isolation. Many of the Ascension echinoderm species 

are consistently different in a variety of ways from 

their conspecifics elsewhere. The reader is referred 

to the systematic section of this paper for details, 

but some species are worth mentioning here in this 

context. 

Ophiactis lymani: Ventral arm plates with convex 

distal edges in St. Helena and Ascension forms. 

Specimens of this species from the eastern and 

western Atlantic do not have convex distal edges 

on ventral arm plates. 

Diadema antillarum ascensionis: Tridentate 

pedicellariae in Ascension and St. Helena population (also Fernando de Noronha ?) with curved 

valves. Valves essentially straight in eastern and 

western Atlantic populations of this species (Diadema antillarum antillarum). 

Pseudoboletia maculata atlantica: There are 

usually five pore-pairs to the arc in Ascension and 

St. Helena populations of this species. In Pseudoboletia maculata maculata there are typically four 

pore-pairs. 

Echinometra lucunter polypora: Ascension and 

St. Helena populations have seven pore-pairs to the 

arc, and the test is purplish adapically. In Echinometra lucunter lucunter there are typically six porepairs, and the test is greenish or white adapically. 

Holothuria (Halodeima) grisea: In comparison 

with West Indian specimens of this species, Ascension specimens have smaller buttons with more 

numerous larger perforations, and the ossicles in 

the tube feet are a different shape. 

Holothuria (Platyperona) sanctori: In Ascension 

and St. Helena specimens of this species, the buttons have numerous small knobs. In contrast, specimens from the eastern Atlantic and Mediterranean 

have buttons with very few knobs or with none. 

These striking and consistent differences from 

presumed "mother" populations prompt enquiry 

as to whether they might be environmentally or 

genetically induced. In the absence of experimental 

evidence (rearing of specimens from different Atlantic localities in uniform environments would be 

most informative), it is almost impossible to answer 

the question. If the differences are genetic, one 

must presume that Ascension is genetically isolated 

from the eastern and western Atlantic, but not from 

St. Helena, and that recruitment of newly settling 

juveniles is entirely internal. 

There is some evidence to indicate that Ascension 

is genetically isolated to a considerable degree. 

Amphi-Atlantic populations of many species are 

virtually identical morphologically, and a genetic 

continuity across the Atlantic has been postulated 

for the echinoids by Chesher (1966). But in the case 

of Ascension, it is notable that (1) several amphiAtlantic species appear not to have been able to 

colonize this island, and that (2) many taxa, including Eucidaris clavata, Diadema antillarum 

ascensionis, and Echinometra lucunter polypora 

appear to have originated from populations elsewhere in the Atlantic, but have not been "swamped" 

by continuing recolonization, nor have populations 

of these taxa apparently become established in other 

parts of the Atlantic (Fernando de Noronha may be 

the exception; this area of the Atlantic requires 

further investigation). 

It also seems evident that colonization by planktonic larval stages is the only method by which the 

Ascension echinoderms have reached the island. The 

absence of dendrochirotid holothurians is attributable to the fact that these animals generally lack 

planktotrophic larvae. Some dendrochirotids disperse by rafting on floating weed. In the tropics, and 

certainly in the case of Ascension, this method of 

colonization is not common. 

The Ascension-St. Helena fauna might be interpreted as being in the third evolutionary phase in 

the sense of MacArthur and Wilson (1967). This is 

the phase of "speciation, secondary emigration, and 

radiation." The process of speciation is obviously 

slow, but establishment of subspecies, especially in 

the echinoids, is proceeding rather rapidly. 

One might contrast the fauna of Ascension with 

that of Bermuda, another isolated island, which 

lies 1075 km away from the nearest land-mass. The 

known echinoderm fauna of Bermuda now comprises approximately 50 species (Pawson, in MS); 

none of these are endemic to Bermuda, and all are 

common in the West Indian region. Only one 

species, Lytechinus variegatus (Lamarck), shows 

slight but consistent differences from its West 
8 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Indian conspecifics. Bermuda is a relatively much 

older island than Ascension (36 million years), and 

thus might be expected to have developed some 

endemic species. The single overwhelming factor 

influencing the Bermuda fauna, however, is the 

Gulf Stream; this gigantic river must be rapidly 

transporting endless numbers of larval and early 

juvenile stages of echinoderms from the West Indies 

to Bermuda. No equivalent physical factor exists 

for Ascension. 

MATERIAL EXAMINED 

This report is based upon material from several 

sources. In 1970, Storrs Olson, National Museum 

of Natural History, took time from his search for 

fossil birds to make some shore collections; these 

included species of echinoderms. Stimulated by Dr. 

Olson's discoveries, R. B. Manning visited the 

island in May 1971, and made general collections 

of shallow-water marine invertebrates; these included an excellent series of echinoderms. Further 

material was obtained during a second visit in July 

1976, to Ascension by a party comprising R. B. 

Manning, M. L. Jones, J. Rosewater, A. J. Provenzano, Jr., and me. A specimen of Ophidiaster 

guildingii collected at Ascension by Mr. A. Loveridge, together with ophiuroids and asteroids collected by the U.S. Eclipse Expedition to West Africa 

in 1890 are described in this report. Some echinoderms collected a few years ago by Mrs. K. M. 

Hutchfield, a former resident of Ascension, and 

deposited in the British Museum (Natural History) 

were kindly sent to me for study by Miss Ailsa M. 

Clark. The small collection in the Ascension Historical Society Museum at Fort Hayes was examined 

during July 1976. 

In the station list below only the 1971 Manning 

expedition and the 1976 expedition stations are 

listed. Miscellaneous records are given under the 

relevant species accounts. The number of specimens 

is indicated after the author of the species. 

R. B. MANNING'S 1971 EXPEDITION TO ASCENSION 

RBM 3: 18 May 1971, Turtl e Shell Beach, beach and rocky 

point (MacArthur Point) at northern edge of South West 

Bay, coarse sand beach and rocky intertidal, 1900-2030, RBM 

and D. Rogers 

Holothuria grisea Selenka, 1 

RBM 5: 19 May 1971, North East Bay Beach and tidepools 

on rocky point west of main beach, temperatur e 27°C, salinity 

38%o, 0900-1100, RBM, D. Rogers, P. Kashulines 

Ophidiaster guildingi Gray, 1 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 1 

Eucidaris clavata Mortensen, 1 (found dry on beach, 

not represented in collections) 

Echinoneus cyclostomus Leske, 2 

R BM 9: 20 May 1971, Turtl e Shell Beach (MacArthur Point), 

northern edge of South West Bay, tidepool with sand bottom 

in lava flow area, 0800-0930> RBM and P. Kashulines 

Isostichopus badionotus (Selenka), 1 

RBM 10: 20 May 1971, rocky point at northern edge of 

English Bay, intertidal pools an d subtidal rocky shore, some 

coarse sand bottom, temperatur e 27°C, salinity 39%o, 1430-

1900, RBM and P. Kashulines 

Eucidaris clavata Mortensen, 1 

Holothuria (Halodeima) grisea Selenka, 1 

R BM 12: 21 May 1971, Turtl e Shell Beach, northern edge 

of South West Bay (MacArthur Point), tidepool with sand 

bottom in lava flow area, 1200-1630 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 7 

Echinometra lucunter polypora Pawson, 1 

RBM 13: 22 May 1971, rocky point off Fort Hayes, Georgetown, algal mats in intertidal, 0800-1100, RB M and D. 

Rogers 

Holothuria (Thymiosycia) arenicola Semper, 1 

RBM 14: 22 May 1971, rocky flat near Collyer Point, rock 

surface at low tide with dense algal mat, area locally known 

as Cable and Wireless Beach, 1100-1130, RBM and D. Rogers 

Echinometra lucunter polypora Pawson, 1 

RBM 15: 22 May 1971, same locality as sta 10, but second 

tidepool from shore as well as more isolated tidepool, 1330-

1600, RBM, D. Rogers, K. Double 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 1 

Eucidaris clavata Mortensen, 1 

Echinoneus cyclostomus Leske, 1 

Holothuria (Platyperona) sanctori Delle Chiaje, 2 

RBM 16: 22 May 1971, Shelly Beach, flat exposed at low tide 

on open beach proper, 1830-2330, RBM and D. Rogers 

Eucidaris clavata Mortensen, 1 

Diadema antillarum ascensionis Mortensen, 2 

RBM 18: 23 May 1971, Shelly Beach, tidepools in flat exposed 

at low tide on open beach, temperatur e 27°C, salinity 40%o, 

1000-1200, RBM, D. Rogers, K. Double 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 8 

Schinometra lucunter polypora Pawson, 2 

R BM 20: 23 May 1971, same as sta 14, 1900-2030, RBM 

Eucidaris clavata Mortensen, 1 

Echinometra lucunter polypora Pawson, 2 

R BM 21: 24 May 1971, rocky point at northern edge of English Bay, tidepools on rocky flat, 0800-1200 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 4 

Ophiactis savignyi Muller and Troschel, 2 

Isostichopus badionotus (Selenka), 1 

RBM 22: 24 May 1971, Turtl e Shell Beach, northern edge of 

South West Bay (MacArthur Point), tidepool about 20 feet 

in diameter with clear, soft sand bottom, 1300-1700 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 1 

Eucidaris clavata Mortensen, 1 
NUMBER 2 

Diadema antillarum ascensionis Mortensen, 1 

Echinometra lucunter polypora Pawson, 3 

Holothuria (Thymiosycia) arenicola Semper, 2 

RBM 23: 25 May 1971, same as sta 22, 0800-1030, RBM, K. 

Double 

Eucidaris clavata Mortensen, 1 

Diadema antillarum ascensionis Mortensen, 5 

RBM 24: 25 May 1971, same as sta 14, 1030-1230, RBM and 

K. Double 

Diadema antillarum ascensionis Mortensen, 7 

Echinometra lucunter polypora Pawson, 17 

R BM 24: 25 May 1971, same as sta 14, temperatur e high pool 

42°C, shore pool 38°C, salinity high pool 32%o, shore pool 

28%o, 1300-1530 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 1 

T H E 1976 EXPEDITION TO ASCENSION 

Asc. 1-76: 11 Jul 1976, MacArthur Point, temperature 25°C, 

salinity 34%o 

IB, associated with rocks 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 12 

Ophiactis savignyi (Muller and Troschel), 2 

Eucidaris clavata Mortensen, 7 

Echinometra lucunter polypora Pawson, 27 

Holothuria (Halodeima) grisea Selenka, 8 

1C, in clumps of coralline algae 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 12 

Ophiactis savignyi (Muller and Troschel), 1 

Echinometra lucunter polypora Pawson, 3 

Asc. 3-76: 12 Ju l 1976, English Bay, temperature 28°C (inner 

pool), 25°C (outer pool), salinity 34%o 

3A, sand, inner tidepool 

Isostichopus badionotus (Selenka), 1 

3C, associated with rocks beyond outer pool 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 10 

Ophiactis savignyi (Muller and Troschel), 2 

Eucidaris clavata Mortensen, 1 

3D, associated with rocks, outer pool 

Eucidaris clavata Mortensen, 13 

Holothuria (Halodeima) grisea Selenka, 6 

Holothuria (Platyperona) sanctori Delle Chiaje, 3 

3G, collected by snorkeling in 5-10 m beyond outer tide 

pool, calcareous sand and rock bottom 

Holothuria (Halodeima) manningi Pawson, 3 

Asc. 5-76: 13 Jul 1976, Shelly Beach, temperatur e 31°C, salinity 3496o 

5A, isolated tide pools in back of open shore 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 2 

Ophiactis savignyi (Muller and Troschel), 6 

Holothuria (Halodeima) grisea Selenka, 1 

Holothuria (Thymiosycia) arenicola Semper, 2 

Asc. 6-76: 14 Ju l 1976, Collyer Point, temperature 26°C, 

salinity 34%o 

6A, isolated tide pools 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 48 

Ophiactis lymani Ljungman, 1 

Echinometra lucunter polypora Pawson, 2 

Echinoneus cyclostomus Leske, 1 

6B, associated with exposed rocks 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 3 

Eucidaris clavata Mortensen, 4 

Diadema antillarum ascensionis Mortensen, 4 

Asc. 7-76: 14 July 1976, off Collyer Point, diving, collected by 

Mr. K. Jourdan 

Ophidiaster guildingi Gray, 1 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 2 

Echinometra lucunter polypora Pawson, 1 

Asc. 8-76: 15 Jul 1976. MacArthur Point, isolated tide pool 

Ophiothrix (Ophiothrix) roseocaerulans Grube, 3 

Asc. 9-76: 16 Ju l 1976, Northeast Bay, temperatur e 25°C, 

salinity 34%o 

9C, isolated tide pool 

Ophiothrix (Ophiothrix) roseocaerulans Grube , 7 

Ophiactis savignyi (Muller and Troschel), 1 

9D, associated with rocks in the intertidal 

Holothuria (Platyperona) sanctori Delle Chiaje, 1 

Class STELLEROIDEA 

Subclass ASTEROIDEA 

Order PAXILLOSIDA 

Family ASTROPECTINIDAE 

Tethyaster magniftcus (Bell) 

Archaster magniftcus Bell, 1882:440. 

Monaster magniftcus.—Koehler, 1908:630, pi. 12: figs. 107— 

110.—Mortensen, 1933a:422, pi. 21: figs. 1-2, pi. 22: fig. 1. 

Tethyaster magniftcus.—A. M. Clark and A. H. Clark, 1954: 

16, pis. 9, 10: figs. 2e-g. 

MATERIAL EXAMINED.—None. 

DISTRIBUTION.—This species is known only from 

St. Helena (40 meters) and Ascension Island (72 

meters). 

Order VALVATIDA 

Family CHAETASTERIDAE 

Chaetaster longipes (Retzius) 

Chaetaster longipes.—Koehler, 1908:632.—Mortensen, 1933a: 

431. 

MATERIAL EXAMINED.—USNM 17473, Ascension Island, 77 

m, collected by William Harvey Brown, 28 Ma r 1890, U.S. 

Eclipse Expedition to West Africa, 4 specimens. 
10 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

REMARKS.—The four specimens are typical of the 

species in all respects. Largest specimen has R = 

52 mm. 

DISTRIBUTION.—Madsen (1950) gives the distribution of this species as western Mediterranean, 

European Atlantic coast as far north as Bretagne, 

off West Africa, Morocco and Cape Palmas, St. 

Helena, the Cape Verdes, the Canaries, and the 

Azores, in 30-1140 meters. 

HABITAT AT ASCENSION.—Not known. 

Family OPHIDIASTERIDAE 

Ophidiaster guildingi Gray 

FIGURE 3 

Ophidiaster guildingii.—Clark, 1921a:79.—Fisher, 1940:269. 

MATERIAL EXAMINED.—RBM 5, 1 specimen; Asc. 1B-76, 6 

specimens; Asc. 3D-76, 1 specimen; Asc. 7-76, 1 specimen. 

Ascension Island, collected A. Loveridge, 31 Aug 1963, 1 

specimen. 

REMARKS.—The smallest specimen has R = 10 

mm (station RBM 5); the largest has R = 52 mm. 

The ratio R/r = approximately 1:8. When alive, 

all specimens were mottled light and dark orangebrown, and none were unicolor red. The adambuFICURE 3.—Left, Ophidiaster guildingi Gray from Ascension. 

Right, O. ophidianus (Lamarck) from the Azores. Note conspicuous difference in shape of adambulacral spines. 

lacral spines (see Figure 3) conform exactly to the 

description of H. L. Clark (1921a), and, thus, in all 

respects the Ascension specimens concur with Clark's 

concept of this species. Fisher (1940) was of the 

same opinion concerning a specimen collected at 

Ascension by the Discovery. Mortensen (1933a) recorded O. ophidianus (Lamarck) from St. Helena, 

noting that his specimens were either uniformly red 

or had mottled coloration; he doubted that the two 

species could be separated on the basis of color 

alone. Chapman (1955) records O. ophidianus from 

the Azores without comment, and this species also 

occurs at the Cape Verde Islands (see A. M. Clark, 

1955). The question of the validity of the two 

species and their limits of variation can be settled 

only by a thorough study of several scattered populations. 

DISTRIBUTION.—Common throughout the West 

Indies (Clark, 1921a), and recorded from Ascension 

by Fisher (1940). O. ophidianus is known from the 

Mediterranean, West Africa, and the islands mentioned above. 

HABITAT AT ASCENSION.—On underside of rocks 

or exposed in intertidal zone. Also present subtidally (Asc. 7-76). 

Linckia guildingi Gray 

Linckia diplax.—Bell, 1881:437. 

Linckia guildingii.—Clark, 1921a:67.—Madsen, 1950:216. 

MATERIAL EXAMINED.—British Museum (Natural History) 

Catalogue No. 1972.1.21.3, collected Mrs. K. Hutchfield, 1 

specimen; Catalogue No. 81.10.27.15, collected T. Conry, 1 

specimen. 

REMARKS.—Both specimens undoubtedly represent this widespread species. One specimen (Catalogue No. 81.10.27.15) is that which was identified 

by Bell (1881) as Linckia diplax. 

DISTRIBUTION.—As Clark (1921) points out, this 

seems to be "a truly tropicopolitan species of seastar, absent only from the western coast of America." 

It has not been reported from St. Helena; according 

to Mortensen (1933a) another species which he 

named Linckia formosa occurs there. L. formosa is 

apparently most closely related to the amphiAtlantic species, L. bouvieri Perrier. 

HABITAT AT ASCENSION.—Not known. Probably 

same as for preceding species. 
NUMBER 2 11 

Subclass OPHIUROIDEA 

Order OPHIURIDA 

Family OPHIACTIDAE 

Ophiactis savignyi (Muller and Troschel) 

Ophiactis savignyi.—Mortensen, 1933a:442; 1936:264.—Clark, 

1955:36.—Madsen, 1970:207, fig. 33. 

MATERIAL EXAMINED.—RBM 21, 4 specimens; Asc. 1B-76, 

2 specimens; Asc. 1C-76, 1 specimen; Asc. 3C-76, 2 specimens; 

Asc. 5A-76, 6 specimens; Asc. 9C-76, 1 specimen. 

REMARKS.—All specimens have six arms and all 

possess the very large radial shields that render this 

species readily recognizable. 

DISTRIBUTION.—According to Madsen 1970) this 

species has a circumtropical distribution in littoralsublittoral depths. It has been recorded from Ascension by Mortensen (1936) and also from St. Helena 

(Mortensen, 1933a). 

HABITAT AT ASCENSION.—Under rocks in tide 

pools. Not uncommon in clumps of coralline algae. 

Ophiactis lymani Ljungman 

Ophiactis lymani.—Mortensen, 1933a:442, fig. 15 —Clark, 

1955:35, fig. 12.—Madsen, 1970:208, fig. 34. 

MATERIAL EXAMINED.—Asc. 6A-76, 1 specimen. 

REMARKS.—This species has been well illustrated 

by all of the authors cited in the synonymy above. 

The single specimen from Ascension is typical in 

most respects. Disc spines are virtually absent, there 

being only one or two at the base of each arm. 

Mortensen (1933a) pointed out that in St. Helena 

specimens the ventral arm plates have convex distal 

margins, whereas in populations from elsewhere, 

the distal margins tend to be concave. In the present specimens the distal margins are convex on all 

ventral arm plates until approximately the 12th 

arm joint, where the margins become concave, and 

then they remain so throughout the length of the 

arm. In alcohol the disc is light and dark gray 

mottled, and the arms are light brown and dark 

gray mottled. 

DISTRIBUTION.—Madsen (1970) described this 

species as an amphi-Atlantic sublittoral form, known 

from several localities off tropical West Africa, from 

the Cape Verdes to northern Angola in 0-90 meters, 

from the Virgin Islands in the West Indies, and 

from St. Helena (10-110 meters). The present 

record from Ascension is therefore not unexpected. 

HABITAT AT ASCENSION.—Under rock in isolated 

tide pool. 

Family AMPHIURIDAE 

Amphiura capensis Lyman 

Amphiura capensis.—-Koehler, 1908:634. 

MATERIAL EXAMINED.—None. 

REMARKS.—Koehler recorded this species from 

Ascension Island, and it has not been collected there 

since. Mortensen (1933a) seriously doubted the validity of this record, and suggested that there had 

been a mistake with the locality labels. Further 

doubt is cast upon the validity of Koehler's identification by Mortensen's (1933b) restudy of Koehler's 

(1914) presumed Amphiura capensis from Angola 

and Senegal; Mortensen found that these specimens 

comprised two genera, neither of which was an 

Amphiura. 

Ophiostigma abnorme (Lyman) 

Ophiostigma abnorme.—Mortensen, 1936:293.—Clark, 1955: 

38.—Madsen, 1970:200, fig. 29. 

MATERIAL EXAMINED.—USNM 17488 Ascension Island, 36-

54 m, collected by William Harvey Brown, 25 Mar 1890, U.S. 

Eclipse Expedition to West Africa, 1 specimen; USNM 17489, 

as above, 72 m, 5 specimens. 

REMARKS.—The six specimens are in fair condition; they are typical examples of this species. None 

have numerous spines on the upper surface of the 

disc; at best they are sparsely scattered. 

DISTRIBUTION.—Madsen (1970) notes that this is 

an amphi-Atlantic sublittoral species. It is also 

known from the Cape Verdes. Mortensen (1936) 

first recorded O. abnorme from Ascension. 

HABITAT AT ASCENSION.—Not known; has been 

taken at 16-27 m (Mortensen 1936) and at 36-72 m. 
12 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Family OPHIOTHRICIDAE 

Ophiothrix (Ophiothrix) roseocaerulans Grube 

Ophiothrix roseocaerulans.—Koehler, 1904:97.—Mortensen, 

1933a:440, pi. 22: figs. 5-7; 1936:2262. 

Ophiothrix (Ophiothrix) roseocaerulans.—A. M. Clark, 1967: 

647. 

MATERIAL EXAMINED.—RBM 5, 1 specimen; RBM 12, 7 

specimens; RBM 15, 1 specimen; RBM 18, 9 specimens; 

R BM 21, 5 specimens; RBM 22, 1 specimen; RBM 25, 1 

specimen. Asc. 1B-76, 12 specimens; Asc. 1C-76, 12 specimens; 

Asc. 3C-76, 10 specimens; Asc. 5A-76, 2 specimens; Asc. 6A-76, 

48 specimens; Asc. 6B-76, 3 specimens; Asc. 7-76, 2 specimens; 

Asc. 8-76, 3 specimens; Asc. 9C-76, 7 specimens. South West 

Bay (MacArthur Point), sandy bottom tide pool, collected by 

Storrs Olson, 12 Jul 1970, 2 specimens; Ascension Island, 

from dead Cymatium shell, collected K. Jourdan, Jul 1976, 1 

specimen. 

REMARKS.—These are typical specimens of this 

beautiful species. The color is highly variable, as 

Mortensen (1933a) had noted for his St. Helena 

material. Most commonly shades of blue to purple 

are represented, but light blue and even pink specimens were collected at Ascension. A. M. Clark 

(1967) in her revision of the family Ophiotrichidae 

referred this species to the typical subgenus Ophiothrix (Ophiothrix). 

DISTRIBUTION.—The species is known to occur 

only at St. Helena (see Mortensen, 1933a) and at 

Ascension. 

HABITAT AT ASCENSION.—Almost ubiquitous in 

the intertidal, encountered in clumps of coralline 

algae, under rocks, and in crevices. It was common 

at all stations sampled. 

Class ECHINOIDEA 

Order CIDAROIDA 

Family CIDARIDAE 

Eucidaris clavata Mortensen 

FICURES 4-7 

Cidaris metularia.—Qe\\, 1881:436. 

Cidaris tribuloides juv.—A. Agassiz, 1881:36, pi. I: figs. 3, 5, 6. 

Cidaris minor Koehler, 1908:638, pi. 16: figs. 136-138. [Although C. minor Koehler, 1908, seems to be the oldest 

available name for E. clavata, it is not available, as Mortensen (1928) has pointed out, because it is preoccupied 

by at least two earlier homonyms.] 

Eucidaris tribuloides.—Clark, 1925:21 [in part] —Mortensen, 

1936:213, pi. 1: figs. 13-15 [in part]. 

Eucidaris clavata Mortensen, 1928:408, pi. 42: figs. 1-4; pi. 

67: figs. 10-11, pi. 73: fig. 2, pi. 86: fig. 15; 1932:169, pi. 4: 

figs. 3-5; 1933a:464. 

Not Cidaris minor Koehler, 1914:217 [=Eucidaris tribuloides 

africana~\. 

REMARKS.—The status of the species E. clavata 

has been in doubt for some time. On the basis of 

St. Helena material, Mortensen described his new 

species E. clavata in 1928, and later (1932, 1933a) 

reinforced his opinion of the validity of the species. Clark (1925) called attention to the clavate 

spines of his St. Helena specimens, but also noted 

that not all specimens had such spines. Later, 

Mortensen (1936) described some small specimens 

from Ascension as E. tribuloides and noted their 

similarity to specimens from Annobon, West Africa 

(now Pagalu, Equatorial Guinea), which he regarded as representing a "var. africana." Comparative measurements made upon small numbers of 

specimens (2 from Annobon, 6 from Ascension, 4 

from West Indies) of small size (largest specimen 

18 mm h.d.) tended to support his contention. Examination of larger series of mature specimens for 

the present paper show that Mortensen's conclusions were erroneous, that the Ascension Eucidaris 

is identical to the St. Helena form, and quite distinct from the West African-West Indian species. 

A complete description of E. clavata is not included here; details can be found in Mortensen 

(1928, 1932). However, it is necessary to discuss 

those characters that are of apparent systematic 

importance. 

Relationship between Areole Width and Width 

of Median Area of Interamb: Mortensen (1936) 

measured the width of a primary areole at the 

ambitus, and compared this with the width of the 

median area of the interamb. He found that in 

two West African species measured the areole width 

exceeded slightly the width of the median area; 

by contrast, in three West Indian specimens of 

E. tribuloides the areole width was less than the 

width of the median area. This supposed difference, together with some others of a minor nature, 

led Mortensen to erect a new variety, E. tribuloides 

africana, for the West African forms. I have made 

additional measurements of some "typical" West 

Indian E. tribuloides, and these are presented 

graphically herein (Figure 4). It is apparent that 
NUMBER 2 13 

0 0 

1 I 

h h 

0 0 

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0.9 — 

0.7— 

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HORIZONTAL DIAMETER OF TEST (MM ) 

FIGURE 4.—Comparison of Eucidaris tribuloides (Lamarck) with E. clavata Mortensen 

(for details, see text). 

tribuloides • clavata (Ascension) £ clavata (St. Helena) Q 

the relationship between dimensions of median 

area and areole approaches unity (median area 

width as percentage of areole width: mean 97%) 

and that, in fact, Mortensen's use of this character 

to distinguish a new variety africana was not justifiable. Chesher (1972) has plotted the same parameters to distinguish E. tribuloides from E. thouarsii; 

his graph shows the same results for the relationship between areole and median interamb area in 

E. tribuloides sensu stricto as does Figure 4 herein. 

In the case of Ascension and St. Helena Eucidaris, 

the situation is somewhat different (see Figure 4). 

Here, the areole is almost twice as wide as the 

median interamb area (interamb width as percentage of areole width: mean 51.5%). It is believed that this character is important in distinguishing E. clavata from E. tribuloides. 

Relationship between Diameter of Peristome and 

Diameter of Apical System: As shown in Figure 

5, for E. tribuloides from West Africa and from 

the West Indies area, the peristome and apical system have approximately the same diameter (apical 

system diameter as percentage of peristome diameter: mean 102%). The West African and West 
14 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

1.2 -

1.1 -

I.O -

0.9 -

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0.7 -

o 

1 

D 

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• 

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HORIZONTAL DIAMETER OF TEST (MM ) 

FIGURE 5.—Comparison of Eucidaris tribuloides (Lamarck) with E. clavata Mortensen 

(for details, see text). 

tribuloides (West Indies) • (West Africa) • 

clavata (Ascension) £ (St. Helena) Q 

Indian specimens are indistinguishable in respect 

to this relationship. In contrast, in Ascension and 

St. Helena Eucidaris, the peristome is considerably 

larger than the apical system (apical system diameter as percentage of peristome diameter: mean 

77%). This character also is regarded as important 

in distinguishing Ascension-St. Helena Eucidaris 

from its congeners on each side of the Atlantic. 

Shape of the Spines: Mortensen (1928, 1932) 

regarded the shape of the spines as a feature of 

paramount importance in distinguishing E. clavata 

from E. tribuloides. He noted that while many of 

his St. Helena specimens had the club-shaped spines 

(such as those shown in Figure 6a-b herein) others, 
NUMBER 2 15 

b 

*Sk . &'£ 

f 

FIGURE 6.—Eucidaris clavata Mortensen: a, St. Helena, 20-30 meters; b, St. Helena, 20-30 

meters; c, St. Helena, shore; d, Ascension, shore; e, Ascension, shore; /, St. Helena, 20-30 meters 

(Specimens a-c, f are in the Zoological Museum, Copenhagen.) 
16 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

particularly from the intertidal area, had more 

slender, almost cylindrical, spines (Figures 6c-e, 7). 

In Ascension specimens the spines are almost invariably cylindrical (Figures 6e, 7); on occasional 

specimens a tendency towards clavate form is exhibited (Figure 6d), but in no case were specimens 

with truly club-shaped spines found. No deeper 

water specimens have yet been recovered at Ascension (apart from Koehler's (1908) Cidaris minor), 

so the true range of spine shape for the Ascension 

Eucidaris is not yet known. Examination of a great 

variety of specimens of western Atlantic E. tribuloides from a variety of habitats in the collections 

of the National Museum of National History revealed not one specimen with a tendency to form 

club-shaped spines similar to those from St. Helena. 

It is believed that, while presence of club-shaped 

spines is a useful indicator of the identity of this 

species, this character is highly variable in its 

expression, and, consequently, is not completely 

reliable. 

Affinities of E. clavata: E. clavata is readily distinguished from E. tribuloides on the basis of relationships between dimensions of peristome and 

periproct, relationships between width of ambital 

areoles and width of median interamb areas, and, 

to a lesser extent on the shape of the spines. 

McPherson (1968) measured some specimens of 

Eucidaris from Ascension to complement his study 

of shape and growth of E. tribuloides, and he regarded the Ascension forms as conspecific with 

E. tribuloides sensu stricto. He did not analyze his 

data, however, in a way which would have indicated 

the obvious differences that exist, for such an analysis was not relevant to his study. 

E. clavata may be derived from E. tribuloides, 

as has been suggested by Mortensen (1933a). The 

eastern Pacific species E. thouarsii closely resembles 

E. clavata in terms of the relationship between 

diameter of peristome and apical system, and in 

relationship between areole width and width of 

median interamb area. Th e two species are distinctly separated on the basis of color alone. A form 

from the Galapagos Islands, often referred to as 

E. galapagensis (Doderlein) resembles E. clavata in 

having club-shaped spines. The interesting parallel 

was noted by Mortensen (1928), who commented in 

some detail upon the status of E. galapagensis. 

The complex of taxa, tribuloides-clavata-thouarsiigalapagensis, requires a thorough analysis, based 

upon large series of specimens. The present arrangement of the species is even now not completely 

satisfactory. Th e intriguing question about formation of club-shaped spines at isolated oceanic 

islands has yet to be investigated; a genetic basis is 

suggested by the slender evidence available. 

DISTRIBUTION.—E. clavata is known only from 

Ascension and St. Helena, in depths of 0-60 meters. 

HABITAT AT ASCENSION.—All specimens were 

found either lodged in rock crevices or under rocks, 

always on hard substrates. Mostly smaller specimens 

of up to 38 mm h.d. were found intertidally. Subtidally, within snorkel diving range, considerably 

larger specimens were found (50+ mm h.d.), usually 

wedged inextricably in deep crevices. Off St. Helena, 

Mortensen (1932) found numerous specimens lodged 

in holes and cavities of the sponge Chondrosia 

plebeia Schmidt at depths of 20-30 meters. 

Tretocidaris spinosa Mortensen 

Tretocidaris spinosa Mortensen, 1903:17, 28, pi. 10: figs. 10, 

11, 16.—Koehler, 1908:636, pi. 16: figs. 163, 164.—Mortensen, 1928:317, pis. 33: figs. 1-3, pi. 34: figs. 1-2, pi. 67: fig. 

9, pi. 71: fig. 15, pi. 82: figs. 32-36; 1932:154, pi. 4: figs. 

6-12, 15, pi. 13: fig. 3; 1933a:465. 

FIGURE 7.—Spines from specimens of Eucidaris clavata 

Mortensen, Ascension Island. 

MATERIAL EXAMINED.—None. 

DISTRIBUTION.—Known from Ascension (72 meters) and St. Helena (50-60) meters. 
NUMBER 2 17 

Order DIADEMATOIDA 

Family DIADEMATIDAE 

Diadema antillarum ascensionis Mortensen 

Diadema setosum—Bell, 1881:436. 

Diadema ascensionis Mortensen, 1909:55, pi. 7: fig. 10, pi. 16 

figs. 1, 4, 8, 16-17, 21-23; 1940:279, pi .48: fig. 2, pi. 54 

fig. 4, pi. 61: figs. 6-11, pi. 73: figs. 14-16.—Tommasi, 1966 

11, figs, 3-5—Lima-Verde, 1969:10.—Brito, 1962:5; 1971 

264, fig. 1. 

Diadema antillarum.—Clark, 1925:42 [in part]. 

Diadema antillarum var. ascensionis.—Mortensen, 1933a:465; 

1936:216. 

MATERIAL EXAMINED.—RBM 16, 2 specimens; RBM 22, 1 

specimen; RBM 23, 5 specimens; RBM 24, 7 specimens; Asc. 

6B-76, 4 specimens. Turtle Shell Beach (MacArthur Point), 

rocky tide pools, collected by Storrs Olson 18 Jun 1970, 1 

specimen. 

REMARKS.—The status of the Ascension-St. 

Helena populations of Diadema has been the subject of considerable discussion, mainly on the part 

of Mortensen (1909, 1933a, 1936, 1940). His final 

conclusion was that these populations should be regarded as a separate species from D. antillarum 

Philippi. The main character upon which the 

separation was based is the shape of the tridentate 

pedicellariae, the blades of which are distinctly 

curved in D. ascensionis, while they are more or 

less straight in typical D. antillarum. This character appears to be reasonably consistent, although 

a survey of USNM material of D. antillarum revealed 

that slightly curved tridentate pedicellariae are common. Mortensen (1940) also stated that in D. ascensionis the median series of primary tubercles in the 

interambs are arranged almost in a straight line, 

whereas in D. antillensis the series remain distinct; 

thus, in D. ascensionis there appear to be five series 

of tubercles in each interamb. Again, this character 

seems to be consistent for Ascension populations, 

but numerous specimens of D. antillarum in USNM 

collections show exactly the same type of tubercle 

arrangement. Mortensen (1940) also notes that the 

spines of St. Helena specimens are "somewhat 

coarser" than those of D. antillarum; this is not a 

reliable character, for the size of the spines can vary 

considerably within populations. 

In view of the broad distribution of D. antillarum 

(see below), and the apparent restriction of D. ascensionis to Atlantic islands or island groups, it would 

seem wisest to regard D. ascensionis merely as a 

subspecies of D. antillarum. 

DISTRIBUTION.—D. a. antillarum occurs on both 

sides of the Atlantic, in the west from Bermuda 

south to Brazil, perhaps to 23°S (Tommasi, 1966), 

and in the east from Cape Verde to the Gulf of 

Guinea (Angola) on the African coast, also the 

Azores, Canaries, and Madeira Islands. D. a. ascensionis is known from Ascension (Mortensen, 1909) 

and St. Helena (Mortensen, 1933a), Fernando de 

Noronha (Clark, 1925; Mortensen, 1940), also Isla 

Trindade (Brito, 1971) and Atol das Rocas (LimaVerde, 1969). Atol das Rocas is only 200 km from 

the coast of Brazil, and possibly the Diadema there 

is antillarum rather than ascensionis. Bathymetric 

range is 0-360 meters. 

HABITAT AT ASCENSION.—Common in tide pools, 

in rock crevices, and partially concealed under 

rocks. 

Order ARBACIOIDA 

Family ARBACIIDAE 

"iCoelopleurus floridanus Agassiz 

Coelopleurus floridanus.—Koehler, 1908:640.—Mortensen, 

1935:612, pi. 68: figs. 5-7, p. 88: figs. 17-18, 31-34. 

MATERIAL EXAMINED.—None. 

REMARKS.—The juvenile specimen, 9 mm in 

diameter, upon which Koehler (1908) based his 

identification is the only specimen of this genus 

so far known from Ascension. As Mortensen (1935) 

points out, only additional adult material will settle 

the question of the identity of the species. He also 

notes that the Ascension form may be C. floridanus, 

or the African species C. interruptus Doderlein, or 

perhaps a new species. 

DISTRIBUTION.-—Ascension Island, 72 meters 

(Koehler, 1908); western Atlantic from West Indies 

to Cape Hatteras, U.S.A., in 90-2380 meters (Mortensen, 1935). 

Order TEMNOPLEUROIDA 

Family TOXOPNEUSTIDAE 

Pseudoboletia maculata atlantica Clark 

Pseudoboletia maculata.—Koehler, 1908:641, pi. 15: figs. 139-

142, pi. 16: fig. 165. 
18 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Pseudoboletia atlantica.— Clark, 1912:344; 1925:131.—Mortensen, 1933a:467; 1943:534, pi. 32: figs. 1-5, pi. 39: fig. 6, pi. 

40: fig. 6, pi. 42: figs. 1-3, pi. 43: figs. 1-2, pi. 44: fig. 1, 

pi. 55: figs. 1, 3, 19, 20. 

MATERIAL EXAMINED.—No specimens in collections being 

described here. 

REMARKS.—Koehler (1908) was the first to record 

this species (as P. maculata) from Ascension, the 

two specimens being collected at a depth of 40 

fathoms off Point Pyramid. Clark (1912) regarded 

the Ascension specimens as a new species, P. atlantica, and Mortensen (1933a) reported the species 

from St. Helena. 

Study of the literature of this species and of another Atlantic Ocean species, P. occidentalis Clark, 

together with examination of specimens of both 

(Table 1), has led to the conclusion that P. atlantica 

should be regarded as subspecies of P. maculata 

Troschel and that P. occidentalis is a junior synonym of P. maculata. A brief analysis is given here 

of the features used in the past to distinguish these 

taxa. 

Pseudoboletia MATERIAL EXAMINED.—P occidentalis Clark: holotype (USNM E4531); 4 specimens 

(USNM E12353) from off Venezuela, 83-186 meters, 

diameters 63, 69, 78, 79 mm; 3 specimens (USNM 

El6203, El6204) from off Florida north of Miami, 

19-21 meters, diameters 60, 76, 85 mm. P. atlantica 

Clark: 3 specimens (USNM El6096, diameter 71 

mm; USNM El 1732, diameter 82 mm; USNM 

E5953, diameter 89 mm) from St. Helena. 

Spicules in Gills: In the gills of both P. atlantica 

and P occidentalis spicules of the bihamate and Cshaped type are numerous. The C-shaped spicules 

appear to be more numerous than the bihamate 

type in P atlantica, and the reverse might appear 

to be true in P occidentalis, but it was found that 

the relative proportions of the types of spicules can 

depend to a great extent upon the area of gill that 

is being studied. The same is probably true for 

P. maculata. It is concluded that this character is 

unreliable. Mortensen (1943:537) referred to the 

"remarkable differences from [the Indo-Pacific species] indiana and maculata . . ." in the matter of the 

spicules of P. atlantica, but apparently did not 

regard a supposed difference as being important systematically. 

Number of Plates on the Periproct: Clark (1921b: 

116-117) noted that "In maculata the periproct is 

covered by about 30 plates," and that in P. occidentalis there are "about 20 plates." In the four 

additional specimens of P. occidentalis examined 

there are more than 30 plates in the periproct, and 

the same situation applies in specimens of P. atlantica. Clearly, no reliance can be placed upon 

this character, as has already been pointed out by 

Mortensen (1943). 

Size and Shape of Primary Spines: Clark (1921b) 

noted that the ambital primary spines of P. occidentalis are "about 12 mm long, terete basally, and 

becoming flattened only slightly near tip"; this situation he contrasted with that in P. maculata, 

where the spines are "markedly flattened, with 

bluntly chisel-shaped tips (though with a terminal 

concavity), and are 14-16 mm long." The primary 

spines of the additional specimens of P. occidentalis 

examined are typically 15 mm or more in length, 

often approaching 20 mm. They are terete basally, 

and the degree of flattening near the tip is highly 

variable. Ambital spines of P. atlantica are similiar, 

but tend to be shorter, averaging approximately 14 

mm in length. 

First Appearance of Inner Primary Tubercle: 

Clark (1921:117) notes that in P. maculata the 

inner primary tubercle in the ambs appears first 

on the seventh, eighth, or ninth plate from the 

ocular plate in specimens 52-55 mm in diameter, 

whereas in his specimen of P. occidentalis it occurs 

first on the tenth-twelfth plate. In the additional 

specimens of P. occidentalis, the tubercles first appear on the eighth to the 14th plate from the 

ocular; the number of plates are correlated to some 

extent with size of the specimen. In a specimen of 

63 mm h.d., the first tubercle appears on plates 

8-9 from the ocular, while in a specimen of 78 mm 

h.d. it appears on plates 11-14. In P. atlantica the 

tubercles appear on plates 8-10 from the ocular. 

These figures confirm Clark's (1921b) own suggestion that this character is "inconstant and unreliable." 

Color of Test: The dark brownish or greenish 

blotches which appear to characterize P. maculata 

are also present on the holotype of P. occidentalis. 

They are present and conspicuous in most specimens 

of the additional material of P. occidentalis. Mortensen (1943) notes that in P. atlantica the blotches 

may be absent, or that there may be some darker 

spots or bands in the median spaces aborally. It is 
NUMBER 2 19 

evident that in the Atlantic Pseudoboletia the test 

coloration is somewhat variable. 

Color of Spines: In all specimens of P occidentalis 

examined, the color of the spines has faded somewhat, but in most cases the spines are greenish 

basally and pale fawn elsewhere, or almost totally 

white. In the holotype and most non-type specimens, 

spines located on the greenish blotches on the test 

are mostly dark green, light only at the tips, a 

feature already noted by Clark (1921b) for the 

holotype. In P. atlantica, according to Mortensen 

(1943) the spines may be whitish, with green or 

brown basal areas, or they may be banded with dull 

green or brown. Clark (1921b) noted that in P. 

maculata the spines are "green at base and redpurple or reddish at tip . . . quite different from 

the pale colors of occidentalis." 

Pedicellariae: In his original description of P. 

occidentalis, Clark (1921b) did not describe the 

pedicellariae in detail, and Mortensen (1943) expressed regret that Clark had not illustrated the 

tridentate pedicellariae he had described as "slender, 

with valves 1.25 mm long." I could find no such 

pedicellariae on the holotype or on the additional 

specimens of P occidentalis. All of the tridentate 

pedicellariae found were of the broad-bladed type, 

none of them exceeding 1.1 mm in total length. In 

all features these pedicellariae closely resembled 

those of P. maculata, P atlantica, and P. indiana. 

It is impossible to determine from Mortensen's 

(1943) figures of tridentate pedicellariae from these 

three species exactly how they differ from each 

other, although he mentions (p. 533, 537) that they 

are essentially the same in P. atlantica and P. indiana, and that those of P indiana and P. maculata 

differ. I do not believe that these differences, whatever they might be, are significant. 

The globiferous pedicellariae also present a confusing picture. Mortensen (1943:531) notes that the 

globiferous pedicellariae in P. indiana "are as in 

P. maculata," but two pages later (p. 533) he states 

that the smaller globiferous pedicellariae "differ 

rather conspicuously in the length of the blade, it 

being distinctly longer than the basal part in 

maculata, scarcely as long as the basal part in indiana." His figures show a conspicuous difference in 

the pedicellariae of these two species. The same 

type of pedicellariae in P. atlantica are virtually 

identical to those of P. maculata, and in P. occidentalis a condition resembling that in P. maculata was 

found, although the blade appears to be relatively 

shorter. 

An extensive study of large series of pedicellariae 

from many parts of the world might settle the 

several problems that exist with regard to the 

pedicellariae in this genus, but on the basis of the 

admittedly scanty evidence now available, it would 

seem that they do not afford the best characters 

for distinction of species in Pseudoboletia. 

Number of Pore-Pairs to the Pore-Arc: All species 

in the genus Pseudoboletia have four pore-pairs in 

each pore-arc, except P. atlantica, which has five. 

In this respect, P. atlantica forms an interesting 

parallel to Echinometra from Ascension (see p. 22). 

The presence of five pore-pairs has been noted by 

Mortensen (1943) in a large specimen of P. indiana 

75 mm in diameter, and, conversely, P. atlantica 

frequently has arcs of four pore-pairs. Mortensen 

(1943) states: 

The pore-pairs are in general arranged in arcs of 5 ... . But 

this is by no means constantly so; some specimens have in 

the main only 4 pore-pairs, or there may be here and there 

a plate with only 4 pairs, most of the plates having 5 porepairs. This has nothing to do with age; thus the specimen of 

94 mm h.d. . . has in the main 4-geminate plates, whereas 

the specimens of 62 and 68 mm have regularly 5-geminate 

plates. 

In the present collection, all specimens of P. occidentalis have four pore-pairs to the arc, and all 

specimens of P. atlantica have five. 

It is concluded that the only reasonably consistent 

difference between P. atlantica and other species in 

the genus is the presence of five pore-pairs in each 

pore-arc. There appears to be no evidence for maintaining P. occidentalis as a species distinct from 

P. maculata; all of the distinguishing features enumerated by Clark fall within the range of variation 

of P. maculata. Further, in view of the fact that 

some other echinoid species at Ascension Island 

have undergone some phenetic changes as a result 

of isolation, environment, or a combination of the 

influences of these factors, the presence of five porepairs would not appear to be sufficient to warrant 

maintenance of P. atlantica as a separate species, 

distinct from P. maculata, and it is here recognized 

as a subspecies of P. maculata. The status of 

P. maculata in relation to P. indiana cannot be 

determined here. 
20 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

DISTRIBUTION.—P. maculata atlantica is so far 

known only from Ascension and St. Helena in 

20-40 meters. P. maculata maculata is known from 

Ceylon, the Philippines and the Macclesfield Bank, 

and the Banda and Timor Sea in 20-70 meters 

(Mortensen, 1943), also southern Japan (Utinomi, 

1954); in the western Atlantic, P. m. maculata is 

known from off Barbados (holotype of P. occidentalis), from off Venezuela in 83-186 meters, and 

from off southeastern Florida in 19-21 meters. 

Tripneustes ventricosus (Lamarck) 

Tripneustes angulosus.—Bell, 1881:437. 

Tripneustes esculentus.—Clark, 1925:124. 

Tripneustes ventricosus.—Mortensen, 1943:490. 

MATERIAL EXAMINED.—None. 

REMARKS.—Bell (1881) first reported this species 

(as T. angulosus) from Ascension and Clark (1925) 

referred again to Bell's specimen, confirming its 

identity as T. esculentus (=T. ventricosus). No further specimens of the species have been taken at 

Ascension, in spite of assiduous intertidal and subtidal collecting in what would seem to be suitable 

habitats for the species. 

Mortensen (1933a) was inclined to believe that 

the record of this species from St. Helena (Cunningham, 1910) was erroneous, for he found no further 

material in his collecting around that island. In 

fact, he suggested that the material of this species 

which was described by Cunningham may have 

been collected at Ascension. 

DISTRIBUTION.—Common in the West Indies and 

the west coast of Africa (Mortensen, 1943). The records from Ascension and St. Helena must be regarded as questionable. 

Order ECHINOIDA 

Family ECHINOMETRIDAE 

Echinometra lucunter polypora, new subspecies 

FIGURES 8-10 

Echinometra acufera Mellis, 1875:219. 

Echinometra subangularis.—Bell, 1881:437.—Koehler, 1908: 

640.—Cunningham, 1910:125. 

Echinometra lucunter.—Clark, 1925:143 [in part].—Mortensen, 1933a:468; 1936:224 [in part]; 1943:357, pi. 41: figs. 1-5, 

pi. 42: figs. 12-14, pi. 43: figs. 1-13, pi. 44: fig. 9, pi. 64: 

figs. 17, 20-24 [in part]. 

MATERIAL EXAMINED.—Holotype: USNM E16206, RBM 24, 

25 May 1971, Ascension Island, rocky flat near Collyer Point, 

rock surface at low tide with dense algal mat, collected 

by R. B. Manning and K. Double. Paratypes: USNM E16190, 

RBM 24, 16 specimens (same data as holotype); USNM 

E16186, RBM 12, 1 specimen; USNM EI6179 (4), USNM 

E16191 (1), RBM 14, 5 specimens; USNM E16184, RBM 18, 

2 specimens; USNM E16185, RBM 20, 2 specimens; USNM 

E16187, RMB 22, 3 specimens; USNM E16180, Asc. 1B-76, 

27 specimens; USNM E16181, Asc. 1C-76, 3 specimens; USNM 

E16189, Asc. 6A-76, 2 specimens; USNM E16182, Asc. 7, 

1 specimen; USNM E16183, Turtle Shell Beach (MacArthur 

Point), rocky tide pools, collected Storrs Olson 18 Jun 1970, 

3 specimens. 

DIAGNOSIS.—Like E. I. lucunter, except that there 

are predominantly 7 pore-pairs to the arc, when 

greatest test diameter of approximately 32 mm is 

reached. Upper surface of test with conspicuous 

tinge of purple; no trace of green color adapically. 

REMARKS.—While I am reluctant to erect subspecies in a group that is poorly known in so many 

ways, there seem to be excellent grounds for regarding the Ascension and St. Helena populations of 

E. lucunter (Linnaeus) as distinct from the "typical" amphi-Atlantic populations. Mortensen (1933a, 

1943) has already called attention to differences that 

he noted in St. Helena specimens of this species, 

and my examination of larger samples of specimens from Ascension and elsewhere tend to confirm 

Mortensen's observation (for the St. Helena specimens) that they are "about to develop into a separate variety" (1943:366). Mortensen's observation 

(1943:366) that the Ascension Echinometra are different from St. Helena specimens in some respects 

are contradicted by my present findings, and I could 

find no morphological differences between Ascension and St. Helena. 

DISTRIBUTION.—Ascension and St. Helena, intertidal and shallow subtidal. 

HABITAT AT ASCENSION.—This is by far the most 

common intertidal species at Ascension. Specimens 

were found in great numbers in high splash pools, 

in pools between tidemarks, and in rock faces at 

and slightly below low tide level. While most were 

occupying shallow burrows in the volcanic rock, 

many were lodged in crevices or were exposed on 

the rock surface (Figure 8). Commonly, specimens 

were found in association with Diadema antillarum 
NUMBER 2 21 

FIGURE 8.—Two contrasting habitats for Echinometra lucunter polypora at Collyer Point, 

Ascension Island: upper, specimens on surface of rock; lower, specimens occupying burrows. 

(Photos: R. B. Manning.) 
22 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

ascensionis. J. Rosewater (pers. com.) found small 

clusters of the gastropod mollusk Hipponyx antiquatus (Linnaeus) in the bottoms of several of the 

burrows after removal of Echinometra. This may 

be merely a fortuitous association, for numerous 

specimens of the gastropod were also found in other 

habitats, not associated with Echinometra. Approximately 20 specimens of Echinometra were washed 

in formaldehyde in search of commensals; none 

were found. 

Echinometra Specimens 

COLOR OF TEST.—In all specimens from Ascension, the upper part of the cleaned test has a distinct purple tinge; the test is white elsewhere. By 

contrast, all specimens from the western Atlantic 

examined have the test either more or less white, 

or more often with a greenish tinge to the upper 

part of the test. Color of specimens from Annobon, 

off West Africa (now Pagalu, Equatorial Guinea) is 

variable; some specimens have greenish tests, some 

have a very pale purplish tinge, while others are 

virtually white. According to Koehler (1914), the 

West African specimens he examined are indistinguishable from the West Atlantic forms. Mortensen 

(1943) noted that West African specimens are 

"darker," but apparently he was referring to color 

of the spines. 

Specimens from St. Helena are all purplish adapiFIGURE 9.—Ambulacrum of Echinometra lucunter polypora, 

new subspecies, showing arcs of 7 pore-pairs. 

cally (Mortensen, 1933a) as they are in USNM collections. 

COLOR OF SPINES.—Mortensen (1943) noted that 

the spines "show all intermediates between wholly 

black and wholly white. .. . It is very noteworthy 

however that all the numerous specimens from 

St. Helena, Ascension, and West Africa that I have 

seen are black." The living specimens at Ascension 

appeared quite black upon superficial examination. 

Preserved and dried specimens have dark green 

spines with purplish tips. The same coloration can 

be found in specimens from Annobon, off West 

Africa (USNM El2263). 

NUMBER OF PORE-PAIRS.—Mortensen (1943) noted 

that in West Indian specimens of E. lucunter the 

number of pore-pairs is "more generally 6 (though 

often 7) to each arc," while in St. Helena specimens 

there are "almost constantly 7 (or often 8. . . ." The 

number of pore-pairs in Ascension specimens were 

counted and results are given below, together with 

data gathered from series of E. lucunter from 

the eastern Atlantic (Annobon) and the western 

Atlantic (St. Croix, Virgin Islands; Key West, Florida; and Curacao). The pore-pairs counted were 

those immediately above the ambitus. See Figure 9. 

Summary of Echinometra Morphometric Data 

ASCENSION ISLAND.—Number of specimens examined, 56. Greatest length 9-64 mm, width 8-64 mm. 

Average width as percentage of length 90%. In 12 

specimens the product of length X width was less 

than 900, and 10 (84%) of these specimens have 

6 pore-pairs to the arc. In the 44 specimens where 

length X width exceeded 900, 24 (approximately 

55%) have 7 pore-pairs to the arc, 3 (7%) have predominantly 7 pore-pairs and 10 (23%) have 6 and 

7 pore-pairs present in approximately equal proportions. None of the latter specimens have 6 pore-pairs 

to the arc throughout. 

EASTERN ATLANTIC.—Number of specimens examined, 15. Greatest length 10-60 mm, width 9-50 

mm. Average width as percentage of length 91% . 

In 11 specimens the product of length X width exceeded 900, and in all of these (100%) the number 

of pore-pairs to the arc is 6. No specimens have 

arcs with 7 pore-pairs. 

WESTERN ATLANTIC.—St. Croix Population: Number of specimens examined, 110. Greatest length 

25-62 mm, width 23-58 mm. Average width as per-
NUMBER 2 23 

centage of length 88%. In 74 specimens the product 

of length X width exceeded 900, and in 66 (89%) 

of these there are 6 pore-pairs to the arc. One specimen had predominantly but not exclusively 7 porepairs, and in only 7 specimens (9%) arcs with 7 

pore-pairs were present in equal numbers with arcs 

with 6. No specimens have 7 pore-pairs to the arc 

throughout. 

Key West and Curagao Specimens: Number of 

specimens examined, 30. Greatest length 19-62 mm, 

width 17-54 mm. In 23 specimens the product of 

length X width exceeded 900, and in 15 specimens 

(65%) there are 6 pore-pairs to the arc. In 4 specimens (17%) there are 7 pore-pairs, and in 4 specimens (17%) 6 and 7 pore-pairs were present in 

approximately equal proportions. 

SUMMARY OF DATA.—The data summarized above 

and presented graphically in Figure 10 show that the 

populations of E. lucunter at Ascension are consistently different from those examined from the 

eastern and western Atlantic in terms of number of 

pore-pairs to the arc. After a length of approximately 32 mm is reached (at which point length X 

width will approximate 900), the typical configuration for Ascension specimens is to have 7 pore-pairs, 

while eastern and western Atlantic forms typically 

have 6. 

The combination of characters here regarded as 

taxonomically important (number of pore-pairs and 

color of test) warrant the erection of a new subspecies to accommodate the central Atlantic populations of the species. 

m 

MOSTL Y B POPE-PAIR S 

6 = 7 POPE-PAIR S 

MOSTLY 7 PORE-PAIR ! 

FIGURE 10.—Numbers of pore-pairs to the arc in three populations of Echinometra lucunter (Linnaeus): a, Western Atlantic (St. Croix); b, Ascension; c, Eastern Atlantic (Annobon). (For details, see text.) 

Order HOLECTYPOIDA 

Family ECHINONEIDAE 

Echinoneus cyclostomus Leske 

Echinoneus cyclostomus.—Bell, 1881:437.—Mortensen, 1948: 

75, fig. 60, pi. 1: figs. 14, 26; pi. 12: figs. 21-23. 

MATERIAL EXAMINED.—RBM 5, 2 specimens; RBM 15, 1 

specimen; Asc. 6A-76, 1 specimen. 

REMARKS.—The four specimens (total lengths 20, 

26, 31, 41 mm) are typical of this well-known 

species, and need no further comment here. 

DISTRIBUTION.—A truly "tropicopolitan" species, 

which ranges the Indo-Pacific and the western Atlantic; it has not yet been recorded from West 

Africa (Mortensen, 1948:79). 

HABITAT AT ASCENSION.—Under rocks on hard or 

calcareous sand substrate. 

Order CLYPEASTEROIDA 

Family ROTULIDAE 

Heliophora orbiculus (Linnaeus) 

Rotula dentata.—Bell, 1881:436. 

Rotula orbiculus—Clark, 1925:175.—Mortensen, 1948:459, 

pi. 57: fig. 1, pi. 72: fig. 4; 1951b:298.—Cherbonnier, 

1959: 49, pi. 7: fig. K; 1963:187. 
24 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Heliophora orbiculus—Durham, 1955:185; 1966:U491, fig. 

377, 4a-c. 

MATERIAL EXAMINED.—None. 

REMARKS.—The inclusion of this species in the 

faunal list for Ascension rests upon the record of 

Bell (1881) of two bare tests. No further specimens 

have been collected at Ascension. The species is not 

known from St. Helena. 

DISTRIBUTION.—From Senegal to Angola (Mortensen, 1940), also Ascension Island (Bell, 1881) and 

the Cape Verdes (Mortensen, 1951b). 

Order SPATANGOIDA 

Family BRISSIDAE 

Brissus unicolor (Leske) 

Brissus unicolor.—Mortensen, 1951a:509, pi. 38: fig. 10. 

MATERIAL EXAMINED.—Ascension Island, collected by divers, 

Ascension Historical Society, approximately 1972, specimen 

on display in Ascension Historical Society Museum, Fort 

Hayes, Ascension Island. 

REMARK.—The single specimen of Brissus unicolor was apparently collected by diving at Ascension Island, and was initially identified by Ailsa M. 

Clark of the British Museum (Natural History). No 

other specimens of the species have been recorded 

from Ascension. The bare test was photographed, 

and approximate dimensions (based upon the photograph) are as follows: length 115 mm, greatest width 

87 mm, greatest height 52 mm, height at level of 

apical system 42 mm, length of left posterolateral 

petal 44 mm, length of left anterolateral petal 

29 mm. 

DISTRIBUTION.—Mortensen (1951a) records the 

species from the "warmer regions of both the 

Western and Eastern Atlantic." The record from 

St. Helena (Clark, 1952) is exceedingly doubtful 

although, in the light of the known occurrence of 

the species at Ascension, it seems quite likely that 

it could also occur at St. Helena. Chesher (1972) 

notes that some specimens of Brissus from the Gulf 

of California cannot be distinguished from B. unicolor, and he considers that this species ranges into 

the eastern Pacific, where its relationships with 

B. obesus Verrill have yet to be determined. 

Class HOLOTHUROIDEA 

Order ASPIDOCHIROTIDA 

Family HOLOTHURIIDAE 

Holothuria (Halodeima) grisea Selenka 

FIGURE lla-e 

Holothuria grisea.—Deichmann, 1930:76, pi. 5: figs. 1-4. 

Holothuria (Holothuria) grisea.—Panning, 1934a:31, fig. 23. 

Ludwigothuria grisea.—Deichmann, 1958:311. 

Holothuria (Halodeima) grisea.—Rowe, 1969:138. 

MATERIAL EXAMINED.—RBM 3, 1 specimen; RBM 10, 1 

specimen. Asc. 1B-76, 8 specimens; Asc. 5A-76, 1 specimen; 

Asc. 6A-76, 6 specimens. 

DISTRIBUTION.—In external features, specimens 

conform with previous descriptions. Color in life 

generally reddish ground color, with yellowish and 

brownish patches marking presence of dorsal tube 

feet. Color in alcohol mottled greyish. Ventral feet 

form conspicuous sole, light greenish-yellow in life, 

brownish in alcohol. 

Ossicles in body wall numerous tables and buttons 

(rosettes). Tables (Figure 11a) with small disc carrying few perforations; generally four large central 

perforations surrounded by four to twelve smaller 

peripheral holes. Edge of disc with approximately 

12 blunt projections. Spire short, with one crossbar, 

and terminating in 12 spines, of which four project 

more or less vertically. Dimensions: average diameter of disc 58 /mi (SD 6.75; SE 2.04); average height 

of spire 51 /mi (SD 4.28, SE 1.29). Buttons (rosettes) 

apparently derived from basic form with 4-6 larger 

holes and variable number of smaller holes (Figure 

lid); edges of buttons indented. Length ranges 

from about 36 to about 45 jum; average length 39 

jam (SD 3.72, SE 1.24). 

Ventral tube feet contain well developed end 

plates, together with rods (Figure lib) with perforated ends; some rods develop four large lateral 

perforations as well. Rods average approximately 

115 tun in length. 

Tentacles contain rods (Figure lie) with perforated ends and with short spines near perforations. 

Tentacle rods greatly variable in size, up to maximum length of approximately 250 /xm. 

REMARKS.—The ossicles of the Ascension representatives of this species show some consistent dif-
NUMBER 2 25 

50 urn 

SQjjm 

d 

5Qjum 50urn 

50um 

5 0 urn 

100 um 

50 urn 100 um 

50um 

100 um 50 um 

FIGURE 11.—Holothuria (Halodeima) grisea Selenka: a, tables from body wall; b, rods from 

ventral tube feet of Ascension specimens; c, rods from ventral tube feet of specimen from the 

Bahamas (USNM 32489); d, buttons from body wall; e, rods from tentacles. Holothuria (Halodeima) manningi, new species: /, tables from body wall; g, buttons from body wall; h, rods 

from tentacles; i, perforated plates from tube feet. Holothuria (Platyperona) sanctori Delle 

Chiaje: /, buttons from body wall of specimen from Naples (USNM 17025); k, tables from body 

wall; /, buttons from body wall. Isostichopus badionotus (Selenka): m, tables from body wall 

of juvenile specimens. 
26 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

ferences from those of West Indian specimens. The 

tables are virtually identical, although those from 

Ascension may be slightly higher. The buttons or 

rosettes are smaller in the Ascension form (Deichmann, 1930:77, notes that they are about 50 /un 

in diameter in West Indian forms), and appear to 

have more numerous larger holes. While very few 

of the ossicles illustrated by Deichmann (1930, pi. 5: 

fig. 1) can be found in the ventral tube feet, most 

are the shape shown in Figure 11&. By contrast, 

tube foot ossicles from USNM 32489, a specimen 

from Andros Island, Bahamas (Figure lie), are 

quite different, with more irregular shape, and few 

complete perforations in the ends. It can be seen, 

however, that both of these ossicles follow the same 

basic pattern. The tentacle rods are quite variable 

in both populations, although the Ascension specimens tend to have rods with more numerous perforations. 

DISTRIBUTION.—Common in the tropical western 

Atlantic (Deichmann, 1930), and also known from 

West Africa (Greef, 1882). 

HABITAT AT ASCENSION.—Fairly common under 

rocks or on sand under rockly ledges. Despite bright 

coloration, difficult to see because of covering of 

particles of sand. 

Holothuria (Halodeima) manningi, new species 

FIGURE 11/—g 

MATERIAL EXAMINED.—Holotype: USNM E16167, total 

length 90 mm. Asc. 3G-76, 12 Jul 1976, English Bay, Ascension Island, collected by snorkeling from depths of approximately 5 m in broad surge channel; substrate rock or coarse 

coralline "sand." Water temperature 25°C, salinity 34%o. 

Paratypes: USNM E16168, total length 95 and 80 mm. Same 

locality data as holotype. 

ETYMOLOGY.—The species is named for Dr. Raymond B. Manning, Department of Invertebrate 

Zoology, National Museum of Natural History, 

who has contributed so much to our knowledge of 

Ascension Island invertebrates by his assiduous collecting and who was the first to discover the specimens described herein. 

DIAGNOSIS.—Deposits include tables of average 

height 54 /mi with completely reduced disk and 

with spire surmounted by 12 projections, and 

minute circular buttons of average diameter 22 /un, 

typically with 2 large and 2 small perforations, but 

nature and disposition of perforations highly variable. 

DESCRIPTION.—Body cylindrical, lacking conspicuous tubercles dorsally. In life, dark brown 

dorsally, darker along mid-dorsal interradius, fading 

to lighter brown on flanks; ventral surface light 

brown. In alcohol, color similar. Tentacles olive 

green in life, yellowish green in alcohol. Skin 

slightly rough to touch due to presence of numerous ossicles. Dorsal and ventral tube feet identical. 

Dorsally, feet sparsely scattered; ventrally, feet much 

more numerous, but not forming conspicuous sole. 

Largest specimen with conspicuous naked band 

along mid-ventral radius, but naked area not obvious in smaller specimens. 

Ossicles in dorsal and ventral body wall identical, 

consisting of tables and buttons. Tables with completely reduced disc; basal portion rounded (Figure 

11/). To p of spire with "maltese cross" comprising 

12 projections, none of which appear to point vertically. Spire with one crossbar. Average height of 

tables 54 /xm (SD 3.63). Buttons minute, tending to 

be circular. Typical form (Figure 1 lg) has four perforations, two larger and two smaller, but nature 

and disposition of perforations highly variable. 

Most buttons with only two perforations. Average 

diameter 22 /xm (SD 2.28). 

Tube feet contain end plates, tables, buttons, and 

flat perforated plates (Figure Hi), usually with two 

larger perforations and numerous small perforations 

at ends. Developmental stages of these plates common. 

Tentacles contain scattered minute straight or 

curved spinous rods (Figure llh), averaging approximately 50 tun in length. 

REMARKS.—This species falls within the subgenus 

Halodeima of the genus Holothuria as defined by 

Rowe (1969). It is immediately distinguished from 

all species listed by Rowe, except Holothuria 

(Halodeima) edulis Lesson, in having tables with a 

completely reduced disc. This Indo-Pacific species 

has tables that closely resemble those of Holothuria 

(Halodeima) manningi, but the buttons in both 

species are very different, for in H (H.) edulis the 

buttons tend to be elongate, have generally larger 

holes, and are frequently reduced to form X-shaped 

granules. Further, this latter species has distinctive 

coloration, being brown dorsally and rose red ventrally when alive (Clark, 1946); this color is quite 

consistent and distinctive. 
NUMBER 2 27 

While relationship with H. (H.) edulis might be 

postulated, H. (H.) manningi appears to bear no 

close relationship to any species of Holothuria in 

the Atlantic Ocean. 

The species was found only at English Bay, and 

only in minimum depths of 3-4 meters. Further 

searching in the English Bay area revealed that the 

species is relatively common and conspicuous, lying 

exposed on rocks and calcareous sand. 

Holothuria (Thymiosycia) arenicola Semper 

Holothuria arenicola.—Deichmann, 1930:66, pi. 4: figs. 1-9. 

Holothuria (Holothuria) arenicola.—Panning, 1935:88 fig. 73. 

Bradtothuria arenicola.—Deichmann, 1958:290. 

Holothuria (Thymiosycia) arenicola.—Rowe, 1969:145. 

MATERIAL EXAMINED.—RBM 13, 1 specimen; RBM 22, 2 

specimens; Asc. 5A-76, 2 specimens. 

DESCRIPTION.—Specimens typical of species. Specimen from RBM 13 is juvenile, with tables only in 

body wall; buttons absent. In adult specimens 

tables average 61.5 pm in diameter (SD 2.70, SE 

0.85) and buttons average 48.8 jnm in length (SD 

1.69, SE 0.56). 

REMARKS.—In all characters examined, specimens 

from Ascension conform well with descriptions of 

the species. Dimensions of ossicles fall within the 

range of variation for H. arenicola. Deichmann 

(1930) noted that there was surprisingly little variation in ossicle size throughout the geographic range 

of the species. 

DISTRIBUTION.—This species is cosmopolitan in 

the tropics, generally living under rocks or burrowing into sandy substrates. 

HABITAT AT ASCENSION.—R. B. Manning noted 

that the specimens collected at RBM 22 were found 

"burrowing deep in bottom of pool." The specimens from Asc. 5A-76 were found under rocks, 

burrowing into coarse calcareous rubble. 

Holothuria (Platyperona) sanctori Delle Chiaje 

FIGURE 11/-/ 

Holothuria farcimen.—Mortensen, 1933a:471, fig. 29. 

Holothuria sanctori.—Panning, 1934b:74, fig. 55.—Tortonese, 

1965:61, figs. 21A, 22. 

Microthele sanctori.—Deichmann, 1958:287. 

Holothuria (Platyperona) sanctori.—Rowe, 1969:145. 

MATERIAL EXAMINED.—RBM 15, 2 specimens; Asc. 30-76, 

3 specimens; Asc. 90-76, 1 specimen. 

DESCRIPTION.—Specimens typical of species in 

most respects, although ossicles show some differences. Tables apparently normal (Figure 11 A), but 

buttons consistently possess several small knobs 

(Figure III). 

REMARKS.—Most typical specimens of H. sanctori 

have smooth buttons, with no trace of knobs on 

their surface. A single specimen from Naples 

(USNM 17025) possesses buttons with few knobs 

(Figure 11/); approximately six knobs per button 

was the largest density observed. The presence of 

numerous knobs on the buttons was also observed 

by Mortensen (1933a) in the St. Helena specimens 

he described as Holothuria farcimen Selenka. 

DISTRIBUTION.—Mediterranean Sea, Azores (Selenka, 1867; Chapman, 1955), St. Helena (Mortensen, 1933a). According to Tortonese (1965), the 

bathymetric range is 5-30 meters. At St. Helena the 

species was collected intertidally, and at a depth of 

40 meters (Mortensen, 1933a). The Ascension records are all intertidal. 

HABITAT AT ASCENSION.—Under rocks on rocky 

substrate. 

Family STICHOPODIDAE 

Isostichopus badionotus (Selenka) 

FIGURE 11m 

Stichopus badionotus.—Deichmann, 1930:80, pi. 5: figs. 30-36. 

—Cherbonnier, 1976:631, pi. 1A-C: fig. 1A-G, fig. 2H-O . 

Isostochopus badionotus.—Deichmann, 1958:280. 

MATERIAL EXAMINED.—RBM 9, 1 specimen; RBM 21, 1 

specimen; Asc. 3A-76, 1 specimen (juvenile). 

DESCRIPTION.—Specimens from station RBM 9 

and RBM 21 are typical of the species. Juvenile 

specimen from Asc. 3A-76, white alive and in alcohol, total length 10 mm. Body wall soft, with scattered tube feet. Ossicles exclusively tables (Figure 

11m) with four central perforations, surrounded by 

eight or more marginal perforations. Spire tall, with 

four or more crossbars. Diameter of tables variable, 

usually 50-60 /mi; spire with same dimensions. 

REMARKS.—Clark (1922) described the ossicles of 

a juvenile 20 mm in length, and in that specimen 

the tables were 75 /mi across and the spire 50 ju.ni 

high, with two crossbars and with teeth on the top. 
28 SMITHSONIAN CONTRIBUTIONS TO MARINE SCIENCES 

Differences from the ossicles of the Ascension specimen are obvious. However, Clark's specimen was 

approximately twice as long as the present one, and 

he noted (Clark, 1922:57) that growth changes in 

the ossicles can be quite dramatic. It does not seem 

likely that two species of Isostichopus occur at 

Ascension Island; thus the juvenile specimen is 

assigned to I. badionotus. 

DISTRIBUTION.—Deichmann (1930) notes that this 

species is distributed over "most of the West Indian 

Seas, from Bermuda to Panama." Greef (1882) reported the species (as Stichopus maculata) from 

West Africa, as did Bell (1883) (as S. assimilis), and 

Cherbonnier (1975) confirmed that I. badionotus 

occurs in West African waters. No stichopodids are 

known from St. Helena. 

HABITAT AT ASCENSION.—Exposed on sand or 

rock. Not common intertidally. 

Order APODIDA 

Family SYNAPTIDAE 

Euapta lappa (Muller) 

Euapta lappa—Clark, 1924:464, pi. 1: figs. 5-7.—Heding, 

1928:136, figs 8.2, 9.4, 10.5, 10.6.—Mortensen, 1933a:471. 

MATERIAL EXAMINED.—British Museum, unregistered holothurian, English Bay, Ascension Island; Ascension Island 

Historical Society, Fort Hayes Museum, Dec 1972, one fragment, anterior end of body. 

DESCRIPTION.—Specimen comprises anterior end 

of body approximately 220 mm in length. Tentacles 

14. Color mottled brown. Ossicles comprise anchors 

and anchor plates, all of approximately the same 

size. Anchors average 368 /xm in length and 210 p.m 

in width, and plates average 233 /mi in length and 

166 ju.m in width. 

REMARKS.—This is a typical specimen of E. lappa. 

The dimensions of the anchors and plates conform 

well with those given by Clark (1924) and Heding 

(1928). 

The label with the specimen notes: "white seaslug apparently is never observed during daylight 

hours. This specimen was recovered during darkness." In spite of searching in a variety of habitats 

during the 1976 expedition, no further specimens 

were found. Apparently the species is not common 

in shallow water. 

DISTRIBUTION.—E. lappa is common in the West 

Indies and the Caribbean area generally. Theel 

(1886) records the species or a close relative, from 

off Teneriffe in the Canary Islands, and Mortensen 

(1933a) described what was probably this species 

from St. Helena. 
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