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Memoirsof the MuseumofVictoria 50(2): 307-323(1990) ISSN 0814-1827

A REVIEW OF THE GENUS SMILASTERIAS (ECHINODERMATA, ASTEROIDEA), WITH DESCRIPTIONS OF TWO NEW SPECIES

FROM SOUTH-EASTERN AUSTRALIA, ONE A GASTRIC BROODER,

AND A NEW SPECIES FROM MACQUARIE ISLAND

By P. Mark O'Loughlin and Timothy D. O'Hara

c/o Department of InvertebrateZoology, Museum ofVictoria, Swanston Street, Melbourne, Victoria 3000, Australia

Abstract

O'Loughlin, P.M. and O'Hara,T.D., 1990.Areviewof thegenusSmilasterias (Echinoder- mata, Asteroidea), with descriptions oftwo newspecies fromsouth-easternAustralia, onea gastric brooder, anda newspeciesfrom Macquarie Island.MemoirsoftheMuseumofVic-

toria 50(2): 307-323.

Anemendeddiagnosis is providedfor thegenusSmilasterias Sladen. Threenewspecies of Smilasterias are described.S. multiparasp.nov.andS.tasmaniaesp.nov.areendemictosouth- eastern Australia, and S. clarkailsasp. nov. is from Macquarie Island.The seasonalgastric broodinghabitofS. multiparasp. nov. isdescribed.Descriptions are given forS.scalprifera (Sladen),S.triremis(Sladen)andS.irregularisH.L.Clark. Akeyto the speciesof Smilasterias and a distribution map forthe three south-eastern Australianspecies are provided.

Introduction

The type species of the genus Smilasterias, S.

scalprifera, and an additional speciesS. triremis, weredescribedby Sladen(1889)frommaterialcol- lected by H.M.S. "Challenger" in subantarctic waters. H.L. Clark (1928) described a third spe- cies S. irregularis from a single specimen in poor condition from South Australia.

Subsequently, H.L. Clark (1938) examined a single specimen from San Remo, Victoria(NMV

F52993),and 17specimensinpoorconditioninthe

MuseumofComparative Zoology which werecol- lectedin Western Port and Port Phillip Bay, Vic-

toria.Heconcluded that theywereall conspecific andclose to S. irregularis. Because of inadequate comparativematerialH.L. Clark (1946) expressed his uncertainty about the number of species of SmilasteriasfromsouthernAustralia, and whether the Australian material was congeneric with that collected by H.M.S. "Challenger".

In her report on the BANZARE asteroids,

A.M.Clark(1962)detailedasinglespecimenfrom MacquarieIslandasSmilasteriassp. (cf.irregularis H.L. Clark),and one fromoff Princess Elizabeth LandasSmilasteriassp.(cf.triremisSladen).The Macquarie Islandspecimen and descriptionof S.

irregularissuggestedtoher thepossibilityofa fur-

thergenus intermediatebetween Smilasteriasand

Allostichaster,butthe lackof comparative material inclinedherto leave the identityofthesespecimens unresolved.

Recentcollectinghasprovided anabundanceof materialfromsouth-easternAustralia,Macquarie Island, and subantarctic and antarctic waters.

There is material conspecific with the San Remo

specimen examined by H.L.Clark(1938),andwith theMacquarieIslandspecimen examined byA.M.

Clark (1962). S. scalprifera (Sladen), S. triremis (Sladen), and S. irregularis H.L. Clark are all

represented. And during museum examinations, material representing anewspeciesof Smilasterias from south-eastern Tasmania has been found.

A singlespecimen(NMV F53029) fromoff the

westcoastofTasmaniaisdiscussed asithas charac- teristics of both Smilasterias Sladen and Allostichaster Verrill.

Abbreviations and Terminology

AM, Australian Museum, Sydney

BMNH, British Museum (Natural History),

London

NMV, Museum of Victoria, Melbourne QVM, Queen Victoria Museum, Launceston, Tasmania

307

https://doi.org/10.24199/j.mmv.1990.50.05

31 March 1990

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308 P. M. O'LOUGHLINAND T. D.O'HARA

SAM, South Australian Museum, Adelaide TM, Tasmanian Museum, Hobart

WAM, Western Australian Museum, Perth

R, length of arm from centreof disc

r, radius ofdisc to interbrachial apex gbr, greatest breadth of arm

ht, greatest height of arm

1, length of spinelet w, medial width of spinelet

abactinal plates, plates on the aboral surface extending from the superomarginal plates

dorsolateral plates, skeletal plates between the carinal and superomarginal plates

autotomy, facility for lossofpartsofthebody under adverse stimulation, generally limited to single arms or parts ofarms (A.M. Clark, 1967)

fissipary, restrictedformofautotomy inwhich

div;siontakes place across the disc and results in the separation oftwo approximately equal parts, bothofwhicharecapable of regeneratingto form a complete specimen (A.M. Clark, 1967)

Asteriidae Gray, 1840 Asteriinae Verrill, 1914 Smilasterias Sladen, 1889 Asterias(Smilasterias) Sladen, 1889: 562, 578.

Smilasterias.-Fisher, 1923: 250,602.-1930: 239.-

1940: 260.-H.L.Clark, 1946: 156.-A.M.Clark, 1962:

85.

Type species. Asterias scalprifeia Sladen, 1889 (subsequent designation by Fisher, 1923).

Diagnosis (emended). Rays5,subcylindrical; Rup to 82 mm; single madreporite, not fissiparous.

Abactinal skeletonfinely reticulate; carinal plates small, often irregular, form fine median longitu- dinal ridge,linked tosuperomarginal platesbyup

to7-16smalldorsolateralplates;dorsolateralarea broad, plates frequently transverselyelongatecreat- ing transverseribbing, irregular series oflongitu- dinal linkages; bothseriesofmarginalplatessmall but distinct; no actinal papulae, lnferomarginal plates with obliquecomb of 2-5 flattened spines;

adambulacral plates with 2-4 spines. Abactinal spinelets numerous, spacedorgroupedon plates, slightlytaperingto clavate, stout to thin. Crossed and straight pedicellariae present; pedicellariaenot clusteredaroundoronspinesorspineletsonrays.

Distribution. Antarctica: Palmer Archipelago.

Subantarctic: off Macquarie, Kerguelen, Heard, Marion, Falkland Islands. SE Australia: from Nuyts Archipelago (SA) to Shellharbour (NSW), BassStrait Islands,northernandeastern coastsof Tasmania. 0-354 m.

Remarks. Sladen (1889) distinguished his ne subgenus Asterias (Smilasterias), containing t

speciesA. scalpriferaandA. triremis, fromothi

"Asterias"groupsbytheobliquecombsofflatten"

inferomarginaland adambulacralspines, the "su compact"dorsolateral skeleton,andthenumeroui groupedabactinalspinelets.However, ontheoth four species now described, and even on son specimens ofS. scalprifera (Sladen, 1889) and .

triremis (Sladen, 1889), thespineletsare spacedan not noticeably grouped together.

In his final re-diagnosis of the genus Fisht (1940) described, amongst other features, tin inferomarginal plates asbeing ontheventrolaten border ofthe ray, thepresenceofaseriesofsma

actinal plates, the first pair of postoral adami bulacralplatesaslonger thanthesecondpair,an., strright pedicellariaescatteredonallray surfaces

None ofthese features is consistent across all o>

the species of Smilasterias. The inferomarginal plates donot alwaysmark adistinct actinolaterai border, variation occurring within species and in the same specimen. Actinal plates may be very reduced in number and size, or lacking, as in thti

small species .S'. tasmaniaesp. nov. Inmost case;' the first pair of postoral adambulacralplates art contiguous, but theyarenot always longer thanthe secondpair. Intwoof the southern Australianspe- cies, S. multiparasp.nov.andS. tasmaniae, there

maybea fewisolated straight pedicellariaeon the actinal interradial surfaces in the former and oni

the oralspinesin thelatter, but otherwisestraight pedicellariae arepresentonlyinthefurrowinthese species.

Thesizeand form ofthepedicellariaein S. mul- tipara and S. tasmaniaeare relatively consistent, butthereisconsiderable variationinthesize,form anddistributionofstraight pedicellariaein S. scal- prifera, S. triremisand S. clarkailsa sp. nov.,and

in the distribution of straight pedicellariae for differentpopulationsin S. irregularisH.L.Clark, 1928.

Tous,themostdistinctivediagnosticcharacteris- tic for Smilasterias is the form ofthe abactinal skeletonasdescribed. However,inmostofthe spe- cies,thereissomevariation betweensimilar-sized specimensinthedegree ofcalcificationofthe skele- ton and in the abactinal plate arrangement. This varies fromareticular arrangement, with upto3 longitudinal linkages and many irregular or Y- shaped dorsolateral plates, to mainly transverse series ofelongate plates withoneornolongitudi- nal connections. This was noted by A.M. Clark (1962) forS. triremis, but itisalso trueofS. scal- prifera, S. clarkailsaand S. tasmaniae. The form

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REVIEW OFSMILASTERIAS(ECHINODERMATA) 309

Table 1. Contrasting characteristics ofthe species of Smilasterias.

Species of Maximum R Dorsolateral Inferomargi- Abactinal Superomargi-Actinal Straight Smilasterias, dis- plates link- nal spines spinelet nalbeading; series of pedicellariae tribution, depth ing carinals perplate. arrange- spinelets per plates outside

range and

superomarg- inals

Shape of spines

ment, shape plate, shape furrow

S. scalprifera 82 mm Up to 16; Combs of Mostly Not beaded. Up to3/4 Rangeof Marion, Kergue- transverse upto 5, grouped. Upto 10. length ofa largeto len. Heard, series with mostly 4. Mostlycla- 1/w = 5-6 ray; 2 series small lanceo- Falkland Islands very irregu- Flattened, vate, 1/w = basally; lateand

40(?15)-267 m. lar longitu- broad, 3-4 plates with incipient

(Typespecies) dinal flared, upto 4, felipedal

linkages. truncate. mostly 2-3

spines.

ones; occur actinally, marginally, in arcs. Rare abactinally.

S. triremis 61 mm Up to8; Combs of Mostly Not beaded. Up to 1/2 Small lanceo-

Palmer transverse upto 5, grouped. Up to 10. lengthofa lateones Archipelago. series with mostly 3. Semi- 1/w = 4-5 ray; plates on allray

Heard, and very irregu- Flattened, capitate to rarely surfaces;

between Heard larlongitu- broad, slightly spiniferous largefeli-

and Kerguelen dinal flared, trun- tapered. 1/w pedal ones

Islands. 93-354 linkages cate to = 3-4 maybe on

m. slightly

rounded

someor all

raysurfaces

S. clarkailsa sp. 35 mm Up to 7; 2 or 3. Flat- Spaced. Fine bead- Up to 1/2 Lanceolate, nov. Macquarie transverse tened, trun- Mostlystout ing. Mostly length ofa sometimes Island. 69-135 serieswith cate, often and cylindri- 2 or3. 1/w ray; maybe felipedal;

m. (4 specimens irregular flared. cal. 1/w = = 2.5 1-5 plates mayoccur

only) longitudinal

linkages.

2.5 with spines actinally,

marginally, abactinally

S. irregularis 65 mm Up to 8; Up to 3, Spaced. Prominent May be up Lanceolate SA, Vic, NSW, transverse mostly 2. Cylindrical beading. Up to4 thin ones may

northern Tas. series, with Flattened, to clavate. to 3, mostly plates in a occuracti- 1-30 m. (readily mostly 1 truncate. 1/w = 3 with 1 on series; may nally, margi- autotomous) irregular not flared the proximal be 1-2 nally and

series of lobe. 1/w = plateswith abactinally

longitudinal 4 spines on NSW

linkages specimens

S. multiparasp. 38 mm Up to 7; 2. Flattened Spaced. Fine bead- Maybeup May beiso-

nov. Vic, transverse truncate, Semi- ing orstria- to6 thin latedones on

northern and series, with not flared. capitate to tions. plates ina the actinal

eastern Tas. 0-3 mostly 2 slightly Mostly 2, series; rarely interradial

m (gastric irregular tapered. 1/w aligned spiniferous. surfaces, or

brooding) series of

longitudinal linkages

= 2.5 transversely.

1/w = 3.5

very rarely

some

actinally.

S. tusmaniae sp. 20 mm Up to 8; 2. Flattened Spaced. Fine stria- None A fewon the

nov. South- transverse truncate, Very stout, tions. oral spines

eastern Tas. 0-8 series, with sometimes sometimes Mostly 2 or m. (3 specimens up to 3 very with slight flared or 3. 1/w = 4

only) irregular

series of longitudinal linkages

waist and swollen end

semi- capitate. 1/w

= 2

(4)

310 P. M. O'LOUGHLIN ANDT. D.O'HARA

oftheabactinalskeletonis relatively consistentin S. irregularisandS.multiparaandhasbeenfigured (fig. 2).

In their keystothe southern generaofAsterii- naebothFisher (1930)andA.M.Clark(1962) refer tothebeadingonthesuperomarginalplatesofthe related genus, AllostichasterVerrill, 1914. A.M.

Clarkspecificallynotedtheabsence ofbeadingfor Smilasterias. However, thesuperomarginalplates ofS. irregularisareprominently beaded. Thoseof S. multipara, S. clarkailsa and the S. sp. (cf.

triremis)specimensometimes haveveryfinebead- ing.TheotherspeciesofSmilasteriashavenobead- ing.Giventheconsistencyof othercharacteristics,

wedonot considerbeadingtobe taxonomicallysig- nificant for Smilasterias.

Theaboral discsurface isgenerally a reticulum of small plates, but in two taxonomically uncer- tainspecimens,the BANZAREspecimendescribed byA.M. Clark (1962) asS. sp. (cf. triremis), and an "Asteriinae" specimen described herein, there are 10 large radialandinterradialplatesbordering the disc and giving the disc a distinctly stellar

appearance. These plates are also present in Allostichaster regularis H.L. Clark, 1928. More specimens are needed before the taxonomic sig- nificanceoftheseplatescan beproperly assessed.

UnlikesomeAllostichasterspecies,noneofthe Smilasteriasspeciesis fissiparous,but onespecies, S. irregularis, is readily autotomous. Museum

specimens ofthis species, includingthe holotype, are rarely intact.

Ineachspeciessmallspecimensdiffer fromlarge ones by having a more compact skeleton, fewer dorsolateral transverse plates, restricted papular areas, feweractinalplates, fewerspineletsperplate, and, inthecasesofS. scalprifera, S. triremisand

S. clarkailsa, feweradambulacral and inferomar- ginal spines.Allcharactersdescribedinthispaper refer to larger specimens unless otherwise stated.

Although the greatest depth recorded for the described species is 354 m for S. triremis, the S.

sp.(cf. triremis)specimenwascollectedfrom 1266 m.

Some of the contrasting characteristics of the speciesofSmilasteriasaresummarizedinTable 1

.

SOUTH AUSTRALIA

Nuyts Archipelago

Shellharbour

35°S

-40°S

Smilasterias irregularis H.L. Clark1928 a Smilasterias multipara sp.nov.

Smilasterias tasmaniae sp.nov.

140°E

150°E

Figure 1. Mapshowingtherecorded occurrence oftheAustralianspeciesofSmilasterias. (EGSS-EastGippsland Scallop Survey).

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REVIEW OFSMILASTERIAS(ECHINODEKMAIA) 3!I

Key to the species of Smilasterias Sladen

10 distinctly larger radialand interradial platesbordering the discaborally Smilasterias sp. (cf. triremis) (Sladen, 1889) (A.M. Clark, 1962) Aboral disc a reticulum ofsmall plates only 2 lnferomarginalplateswithcombsofpredominantly 3-4 flared spines;acti- nal serieslong, uptohalf the length ofa rayorlonger; abactinal spinclets oftengrouped;upto2crossed pedicellariaeperspinelelonrays abactinally 3

lnferomarginal plateswith 2-3 spines, often flared; actinal series long, up to half the length of a ray; abactinal spinclets not grouped; 3-4 crossed pedicellariaeperspineleton raysabactinally Smilasteriaselarkailsasp. nov.

lnferomarginalplateswithpredominantly2spines,not flared; actinalseries short or lacking, up to 6 plates; abactinal spinelcts not grouped; up to 2 crossed pedicellariae per spinelet on rays abactinally 4 lnferomarginalplateswithpredominantly4spines;adambulacralplateswith predominantly3spines; straight pedicellariaerare abactinally; actinal plates spiniferous Smilasterias sealprij'era (Sladen, 1889) lnferomarginal plateswithpredominantly3spines;adambulacralplateswith predominantly2spines;straight pedicellariae abactinally; actinal plates rarely spiniferous Smilasterias triremis (Sladen, 1889) Short series ofthin actinal plates present on rays; pedicellariae present on upper abactinal surface; oral spines lacking pedicellariae; rays long, with

only slight proximal swelling, R/gbr >4 5

Scriesofactinal plates lacking; upperabactinal surface lackingpedicellar- iae;a fewpedicellariaeonoral spines; rays short,swollen proximally, R/gbr

< 4 Smilasterias tasmariiae sp. nov.

Superomarginalplatescontiguous or Imbricatinglongitudinally, withtrans- verse papularareas very rarelycontinuous between them; superomarginal plateswith mostly 3 spinclets, one on a prominent proximal lobe; mostly one irregular series of longitudinal dorsolateral plate linkages along mid- ray; readilyautotomous; livecolour mostly mottled reddish-brownandcream Smilasterias irregularis H.L. Clark, 1928 Superomarginalplatesoftenseparatedlongitudinally,withtransversepapular areascontinuous between them; superomarginal platesmostly with 2 spine- lets,aligned transversely; mostly 2irregularseriesoflongitudinal dorsolateral platelinkagesalongmid-ray;not readilyautotomous;livecolour verydark grey over pale cream Smilasterias multipara sp. nov.

Smilasterias multipara Sp. nov. tidalpools,8Feb 1986, M.O'Loughlfn, WAM428-86(5);

Tasmania, Stanley, 6 Nov 1979, J.R. Penprase, TM

Plate I a, b, figures I, 2, 3 H1546 (2 brooding); Greens Beach, 28. Oct 1978, M.

.,.,,.. . . ., . ,., , ,~. ,, , ,.,.,,. O'l.ouglilin,NMV153027(1 brooding);I,ulworth,22Nov

Smilasterias irregularisII.E.Clark, 1928. II.I..Clark, J * .., ....,, ,,.,„,', ,

,,,10 ...„,. , 1982, M. () l.oiiglilin, NMV 153035 I brooding I 2.

1938: 195 (in part). ,.,. . . , ...\ _ .... ,,,

,,.,,. .. ,. , ,. ,-., , Oilier nialeiial. Vieloria, (ape Hiidgcwalcr, 20 Jan,

Smtlasteriassp^MsnneResearchGroupofVictoria,

^

NMV FJ302g(])i NMV F53034(10), NMV

L

F53039(3); CastleCove, 29 Dec 1986,NMVF53573(53);

Materielexamined. Holotype. Victoria, Flinders,ocean Bushrangers Hay,28Mai 1981,NMV F53020(2);25Jan platform, lowerinlerlidalpool, 12. Ian 1986,M.O'l ongli 1986, NMV 1-5.3031(7); Flinders, 26 Apr 1935, NMV

lin, NMV F53036 (dry). I 52994(1); 16 Jan 1968, NMV 1-52996(1); 6 Inn 1969, Paratypes.Typelocality, NMV l<53030(3 specimens), NMVF53000(2);6Sep 1969,TM111594(10); 17Dee 1969,

NMV F53033(8), NMV F53037(l), AM J20I99I5), NMV F53002(5); 8 Mai 1976, NMV I 53005(10), AM UMNH 1986.10.1.1-5(5); Victoria,CapeBridgewater,20 19915(5); 26 Feb 1977, NMV F53007(8); 14 Jan 1979, Jan 1979, M.O'l.ouglilin, NMVF53011(12); Bushrangers NMV F53008(l),NMV F53010(8); 10Mar 1980, NMV

Hay, lower interlidal pools, 25 Ian 1986, M. O'l ongli- I'530I6(5); 7 Apr 1980, NMV F53017(l); 16 Nov 1980.

lin, SAM KI760(5); Minders, oceanplatform, Iowa inter- NMV I 53018(3); 22 Jan 1982, NMV 1.53021(5); 26 Dei

(6)

312 P. M. O'LOUGHLIN ANDT. D. O'HARA

1983, NMV 1-53025(1); 12 Dec 1985, NMV 1-53026(11);

8 Feb 1986, NMV 1-53032(26); 3 Nov 1986, NMV

1-53046(15 brooding), NMV F53047(31); 2 Aug 1987,

NMV 1-53574(6); 9Oct 1987,NMV F53575(4I brooding

l 61); Western Port, 10 .Ian 1970, NMV [-53006(1);

Crawfish Rock, 15 Feb 1969, NMV 1-52999(1); Balnar- ring,29Nov 1969, NMV 1-53001(2); Phillip Island,Cal Bay, nodale, NMV 1-53004(3); Kitty Miller Bay,7 Apr

1968, NMV 1-52997(5); 25 Oct 1987, NMV 1-53571(

I

brooding);SanRemo,coll.,G,Coghill 28 Jan 1909,iden- tified by H.I . Clark as S. irregularis (seeClark, 1938:

195), NMV F52993(l);Capcliptrap,7Mar 1982,NMV

1-53022(2); Walkerville 7 Mar 1982, NMV 1-53023(2).

Bass Strait islands. King Island, Narracoopa, 30Sep [935, NMV1-52995(4);8Mar1980,NMV F53012(3); City ol'MelbourneBay,Nov 1969,2-3m, I'M H1646(2);Cape Wickham,9Mar 1980,NMV 1-53013(2);Cunie, 10Mar

1980, NMV 1-53014(6); C.ulchway. 10 Mar 1980, NMV

1-53015(7), Frith Island, May 1974, NMV 1-53003(2),AM

J16596(2).

Tasmania. West Point, 9 Dec 1977, AM .111401(2);

Manawah, Green Point, 21 Jan 1975, AM .19018(1);

Hunter Island, Jan 1954, AM .16843(7); Circular Head,

Highl'ieldPoint, I 14Jan 1983,TMHI768(23);Jacobs Boat Harbour, 31 Jan 1969,TM 111592(13);PortFatla, Cowrie Beach, I Dec 1968, NMV 1-52998(1); Western Bay, 29May 1979,TM 111532(3); Burnie, Somerset, 29

Jan 1972, WAM 670-76(2); Ulverslone, Aug 1934,

QVM(l); Devonporl,east,24 Nov 1984,TM HI855(1);

(oles Beach, 14 Mar 1977, AM .110556(1); 10-13 Dec 1977,TM111916(1); 1-12Dec 1982,TMHI752(1);Greens Beach, 24 Jun 1961, QVM(4); 30Oct 1965, QVM(12);

16Apr 1975,QVM(3);24Mar1976,QVM(9);7Apr1976,

QVM(4); 8 Apr 1976, QVM (21); 28 Oct 1978, NMV

1-53009(1), NMV F53040(l); 7 Mar 1981, NMV

153019(6);3 May 1986,NMVF53572(4);CapePortland, 2 Mar1969,TMHI121(8), TM HI4I6(1); 28Mar 1971,

TM 111645(5);Jan 1980,QVM(l);(ieorgeRocks, 19Nov

1977, OVM(4); Bicheno, 21 Nov 1968,TM H794(4); 21

Nov 1981, NMV 1-53042(1); 12-13 May 1983, TM

H1797(1);Coles Bay,23Apr1972,TM H1644(4);20Nov

1982, NMV 1-53024(1); Eaglehawk Neck, 30Mar 1970,

TM HI140(3); Port Arthur, 28Feb 1971,TM H1641(1);

23 Mar 1971, TM H1642(2); 3 Jun 1971,TM H1643(4);

Safety Cove, 28 Apr 1974, TM E1639(2); Point Pucr, oppositeDead Island, 13 Dec 1972,TM H1640(l);Bruny Island, Variety Bay, 30 Jan 1967, TM HI593(5).

Distribution (fig. I). Victorian coast from Cape Bridgewater (38°23'S, 141°25'E) to Walkerville (38°52"S, 146°0'E); BassStrait Islands; Tasmanian

coast from West Point (40°55'S, 144°37'E) to Variety Bay, Brunyisland (43°12'S, 147°26'E). 0-3 m.

•igure2. Schematicdrawingofthearrangementsof theskeletal plates,andthe dispositionofthe spineletsandbeading onthesuperomarginalplates, forproximalsectionso\'the raysof: 1,SmilaslcriasirregularisH.F.Clark(NMV

1-53048), with I serieso(longitudinal dorsolateral linkages,superomarginals imbricatinglongitudinally, a spinelet ontheproximal lobe ofthesuperomarginalplates,and prominentbeading;and2, S. multiparasp. nov.(NMV

F53039), with2seriesoi'linkages,superomarginalsnotimbricating,spineletsalignedtransversely,andfinestri-

atums. (C, carina], D. dorsolateral, S, superomarginal, I, inferomarginal. R.H.S. is adoral.)

(7)

REVIEW OF SMILASTERIAS(ECHINODERMATA) 313

Etymology. From the Latin multus (many) and parere(to bear), inreferencetothebrooding habit of bearing many young.

Description.Holotype. 5 rays; R = 30, 29, 28, 26, 24mm; r = 4mm;gbr = 6 mm;ht = 6mm; R/r

= 7.5; R/gbr = 5. Rays subcylindrical; fine

median longitudinal ridge along rays, transverse ribbing; rays constricted basally, slightly swollen proximally, tapered to roundedtip; interbrachial arcsacutelyangular.Abactinalskeleton veryfinely reticulate;discanirregularreticulumofsmallplates aborally; smallest raywithirregular plating; single madreporite at aboral apex ofinterbrachial arc, surroundedby9spinelets.Papularareasextensive;

irregularondisc, upto 1.0mm long; transversely elongateonrays,upto 3.0mmlong,often extend- ingbetweensuperomarginals; 1-5papulaeperarea;

no actinal papulae.

Carinal series of mostly regular quadrilobed plates up to 0.8 mm wide, imbricating proximal overdistallobes;seriesirregularalong1ray, basally

on 2 rays. Carinals linked to superomarginals by regulartransverseseriesofupto6rod-like, cruci-

formorY-shapedplates; 1 or2 irregular seriesof longitudinal dorsolateral linkages; dorsolateralarea up to 5 mm wide transversely. Superomarginals alternateinalignmentwithcarinals; narrowlycru- ciform, up to 2 mm long transversely; imbricate withdorsolateralsandinferomarginalstransversely, oftenseparated longitudinally; finelybeadedcen- trally; 32 superomarginals for R = 30 mm.

Inferomarginalscorrespondinnumberandalign-

mentwithsuperomarginals;upto 1.2mmlongitu- dinally, imbricating strongly; up to 1.2 mm

transversely, with tapering verticallobe imbricat- ingunder superomarginals; inferomarginals form

actinolateralray margin. Short actinalseries of6

Tf-'

"3M-. •..

jf:' /^«*^."v^vS*-- "-apaKV

..<?• k../\ --vvL. vJ'x \; *• St. .-. Vi*»**«;?a

5.0 mm

Figure3.Aboral viewoftheexposedlobes of the cardiacstomachof Smilasterias multiparasp.nov.,showingsome brood juveniles. (Paratype NMV F53027)

References

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