Studies on the Crustacea of the Turks and Caicos Islands, British West Indies I. Four New Marine Isopod Crustaceans from the Vicinity of Pine Cay

10 Pages·1991·6.8 MB·English

by  Brian Kensley

GulfResearch Reports. Vol. 8. No. 3. 237—246, 1991
STUDIES ON THE CRUSTACEA OF THE TURKS AND CAICOS
ISLANDS, BRITISH WEST INDIES L FOUR NEW MARINE
ISOPOD CRUSTACEANS FROM THE VICINITY OF PINE CAY.
BRIAN KENSLEY AND RICHARD W. HEARD^
^Department ofInvertebrate Zoology, National Museum ofNatural History,
Smithsonian Institution. Washington, D.C, 20560
^Invertebrate Zoology Section, GulfCoast Research Laboratory,
P.O. Box 7000, Ocean Springs. Mississippi 39564
ABSTRACT Four undescribed species ofshallow-water marine isopods were recently collected in the
vicinity ofPineCay inthe westernCaicosIslands. Theseare described and includethe anthuridLicranthura
tuberculata, possessing a tuberculate third article of the antenna and a rounded distolateral angle of the
uropodal exopod: the anthurid Mesanthura spongicola, which has a distinctive color pattern, distinctly
attenuated body, and 5-7 spines on the third article of the mandibular palp: die paranthurid Califanthura
minuta, a tiny (1.6 mm) species having a reduced, triangular uropodal cxopod; and tire stenetriid asellote
Stenetrium caicosensis, which has a pronounced lobe on the merus ofpereopod 1 in the male.
Introduction =5>6>7<P.Pleonitesshort,free, 1-5ofsimilarlength,
pleonite 6 dorsally demarked. Telson widening to pos-
The fauna of the Turks and Caicos Islands, British teriorly rounded serrate/crcnulaie margin.
West Indies, is poorly documented, especially formany Cephalon with well pigmented eyes. Antennular
marine invertebrate groups including the Isopoda. peduncle with basal article widest; flagellum of 3 ar-
DuringthecourseofparticipatingintheTurksandCaicos ticles, first very short, terminal article bearing 2 aes-
Coral ReefEcologyProgram sponsoredby the Oakleigh thetascs. Antennal pedunclewith article 3 having4teeth
L. Thome Foundation, the second author collected iso- on mesial margin, dorsal surface with several small
pods from a variety of shallow-water marine habitats, tubercles plus stronger distal tooth; article 4 offset at
mainlyaroundPineC^yandFortGeorgeCay. Finemesh right angle on article 3,short, about two-thirds lengthof
kicknets, yabby pumps, an Ockelmanndredge, and light article 5; flagellum of8 setose articles. Mandibularpalp
trapswere allusedinthiscollection, withSCUBA at the of3 articles, articles 1 and 3 subequal, each about half
deeperstations. Fourundescribed marine species found lengthofarticle2;article3bearing3distalspines;incisor
during the survey and theirdescriptions are the subject of 3 blunt cusps; lamina dentata having 5 serrations;
ofthis report. While the marine isopods ofthe general molarabsent. Maxilla having 5 distal spines. Maxilliped
CaribbeanandBahamianregionhavebeenbroadlydealt with endite short,blunt; palp of5 articles, article 1 very
within Kensley andSchotte (1989), this is the first ofa short,articles2-4subequal,aboutaslongaswide,article
series ofreports (see SchotteandHeard 1991, Schotte et 5 very small.
al 1991)dealingwithisopodsspecificallyfrom theTurks Pereopod 1 more robust than pcrcopods 2 and 3,
and Caicos Islands. articles squat; carpus triangular, lacking free anterior
margin; propodus roughly rectangular, posterior margin
Results straight,bearing fewsimplesetae,2fringedsetaeantero-
distally; dactylus having several blunt corneous tu-
bercles on posterior surface, unguis short, squat, with
Family Anthuridae
Licranthura tuberculata, new species bifid accessoryspine atbase. Pereopods 2 and 3similar,
carpus with anterior margin barely free; propodus with
Figs, I”3 strong toothed posterodistal spine; unguis almost three-
fourths length ofrest ofdactylus. Pereopods 5-7, carpus
Material. HOLOTYPE,USNM243474,femaletl3.2 with free anterior margin shorter than posteriormargin,
mm,PARATYPE,USNM243475,maletl3.2ram, from with toothed posterodistal spine; propodus with toothed
yellow sponge, 37-40 m, 10 Nov 1988. posterodistal spine; unguis about two-thirds length of
Description. Female: Body slender, about 12 times rest of dactylus. Pleopods similar, pleopod I slightly
longerthan wide. Faint red-brownpigmentationdorsally larger than following, both rami having opercular func-
onpereoniies 2-6. Body proportions: C<1>2 =3<4 tion, endopod longer and narrower than exopod, each
with 5 or 6 distal plumose setae. Uropodal endopod roughly ovate, with margin serrate to crenulate; exopod
ManuRcript received August 9, 1990; accepted October 16, 1990.
237

New Marine Isopods from Turks and Caicos Islands 239
Fig. 2. Licranthura tuberculaia^ new species, female; A, pereopod 1; B, pereopod 2; C, pereopod 7.
laterally broadened, distally emarginate, with lateral onlyotherspeciesinthe genus,inhavingfewerteethon
lobebluntlytriangular,lateralmarginserrateandsetose. the mesial margin ofthe third antennalpeduncle article,
Male: Body similar to iemale; eyes enormously en- a posteriorly more rounded telson, and a blunt (as
larged, dorsally almost contiguous. Antennular flagel- opposed to an acute) distolateral lobe on the uropodal
lum of about 9 aesthetascs-beaxing articles. Antennal exopod.
peduncle article 3having4distal acute tubercles,article Etymology. The specific epithet refers to thetuber-
4 offset atright-angle on article 3; flagellum of7 setose culate nature of the third antennal peduncle article.
articles. Pereopod 1, propodal width slightly more than
twice anteriorlength,withfew simple and fringedsetae Mesanthura spongicoUh new species
posterodistall5r, dactylus with low blunt tubercles on Fig. 4
posterior surface, unguis about half length of rest of
dactylus, with short squat accessory spine. Pleopod 2, Material. HOLOTYPE, USNM 243479, non-ovig.
exopodof2articles,proximal about halflengthofdistal female total length (tl) 6.5 mm, PARATYPE, USNM
article; endopod with copulatory stylet articulating in 243480, 14 non-ovig. females tl 5.3 - 6.5 mm, G<mL
proximalhalfofmesialmargin,reachingslightlybeyond 1149, 3 non-ovig. female 5.3-6.5 mm, in yellow tube
apex of ramus. sponge{Verongiasp.) on fringing reef,offPine Cay, 25
Remarks. Thepresent speciesdiffers from L. amyle - 28 m, 11 Nov 1989. PARATYPES,USNM 243481,2
Kensley and Schotte, 1987, from Belize, the type and non-ovig. females U 4.3 & 4.8 mm, in sponge on outer

New Marine Isopods from Turks and Caicos Islands 241
fnngingreef, offPine Cay, 12 m, 4 Nov 1989. PARA- species ofsponges, were taken along the fringing reef-
TYPES,USNM243483,2non-ovig. femalesU3.2&5.8 faceoffPineCay,Af,spongicolawasfoundtooccuronly
mm, in Verongia sp. offouterreef, Pine Cay, 20 m, 31 with the yellow tube sponge. Specimens were foundin
Oct 1988, sixoftheeightspecimens ofVerongia examinedduring
Description. Female: Bodyproportions, C= 1 =2> thefall(Oct-Nov)of1988and1989;however,duringthe
3<4>5>6>7<P. Pleonite 6dorsally free, posterior spring (April- May) of 1989 and 1990 no specimens of
margin bilobed. Telson with posterior margin broadly M.spongicolawerefoundinover20yellowtubesponges
rounded, with 2 pairs of short and long apical setae from the same collecting area. Ofthe approximately 30
mesially. Antennularflagellumof4 articles, subterminal described species of Mesanthura, only three, viz. M.
article with 1 aesthetasc, terminal article with 2 aes- albinotata Thompson, 1951, Af, bipunctata Thompson,
thetascs. Antennal flagellumof4 setose articles. Mandi- 1951, andAf.protei Kensley, 1980, havebeen collected
bular palp of 3 articles, article 2 longest and broadest, with, or found in sponges (See Negoescu & WSgele
withsinglestrongdistalseta, article 3having5-7distal 1984).
spines; lamina dentate with 5 serrations; molar reduced Etymology. The specific epithet, meaning ‘sponge
toroundedboss. Maxillawith6distalspines, Maxilliped dweller’, refers to the fact that all the specimens ofthis
lacking endite, palp of3 articles, terminal article semi- species were taken from sponges.
circular in outline, with 7 setae on mesial margin.
Pereopod 1 subchclatc, carpus triangular, posterodis-
tally rounded; propodus moderately expanded, length
about2.5timesgreatestwidth,palmsinuous,bearingfew
setae; unguis subequal in length to rest of dactylus. Family Paranthuridae
Pereopod2,propoduswithanteriorlengthalmost3times Califanthura minutch new species
greatest width, with posterior margin bearing numerous Fig. 5
scalesplus tricuspidposterodistal spine; dactyluswith 2
lowproximalteethonposteriormargin,unguisabouthalf Material. HOLOTYPE, USNM 243271, ovig. fe-
length of rest ofdactylus. Pereopods 4-7, carpi with male U 1.6 mm, PARATYPES, USNM 243272, 2 non-
anterior margin shorter than posterior, with short po.s- ovig.femalestl1.6mm,offPineCay,innerfringingreef,
terodistal spine; propodiwith fringedscales onposterior in coarse sand and rubble, 1.5 m, 3 Nov 1988. PARA-
margin plus 2 stout fringed setae and tricuspid ^ine TYPE, USNM 243273, non-ovig. female cl 1.6mm, off
posterodistally; unguis about one-third length ofrest of Pine Cay, incoarse sand andrubble, 5 m, 16Nov 1989.
dactylus. Pleopod 1 exopod operculiform, about 3.5 PARATYPE, GCRL 1148, 1 non-ovig. female, 1.6 mm,
times wider than endopod, latter shorter than exopod, off Pine Cay, back of fringing reef in coarse sand and
with 6 distal plumose setae. Uropodal endopoddistally rubble, 4 m, 16 Apr 1989.
C<1=2<3<4>
rounded, length about 1.5 times basal width; exopod Description. Bodyproportions:
reaching beyond base ofendopod, apically acute, with 5>6>7. Cephalonwithlowroundedrostrum;eyeswell
shallow distal emargination in lateral margin. pigmented,consistingof6-8 ommatidiaeach.Pereonite
Color pattern. Red-brown patches of chromato- 7 about one-sixth length of pereopod 6, lacking legs.
phores on dorsum of cephalon, all pereonites, pleon, Pleonites 1-5 fused; pleonite 6 dorsally indistinguisha-
telson,anduropods,thoseonpereonitesandpleonhaving bly fused with telson. Latter tapering posteriorly to
elongate unpigmented median area. broadly rounded posterior margin, Antennularpeduncle
Remarks. OftheeightknownspeciesofMesanthura with basal article longest and broadest; article 2shorter
from the westernNorth Atlantic,Af. spongicola is most than article 3; flagellum of2shortarticles, distal article
similar toM. biyittata Kensley, 1987> from Belize and bearingseveralsimplesetaeplus2aesthetascs. Antennal
M. looensis Kensley & Schotte, 1987, from the Florida peduncle with article 3 about half length of article 4,
Keys.ThenewspeciescanbeseparatedfromM.biyittata which in turn about half length of article 5; flagellum
by the presence of 5 - 7 spines on article 3 of the consisting ofsingle setose article. Maxilla having about
mandibularpalp andpereopods2- 6each havingastout 12distal serrations. Pereopod 1,carpusdistallyroUnded;
tricuspid sensory spine at the posterodistal angle ofthe propodus broad, expanded, with rounded lobe at proxi-
propodus. The di.stinctly more elongate body form and malendofpalm,having3stoutbasallysituatedsetaeon
the dorsal pigment pattern distinguish M. spongicola mesial surface, palm with lateral convex flange bearing
from M. looensis. Pereonite7 ofAf. spongicola has the few setae. Pereopod 2, propodus barely inflated, with 4
pigment patch in a thickirregular U-shape, whereas the shortspinesonposteriormargin.Pereopod6,carpuswith
pigment in this area inM. looensis isin the shape ofan anterior margin shorter than posterior, latter bearing 2
acute triangle or tapers anteromedially. distal spines on posterior margin; propodus about 2.5
Collectiondata indicate thatM. spongicola is associ- times longerthan wide, with single strong posterodistal
ated with, and lives in a yellow tube sponge, Verongia spine.Pleopod 1,endopodelongate,slender,with3distal
sp. Althoughnumerous benthicandepibenthic samples, plumose setae; exopod broad, operculiform, with about
whichrepresentedavarietyofsubstrataandover10other 8 plumose setae on laterodistal margin. Uropodal endo-

W
New Marine Isopods from Turks and Caicos Islands
pod ovate, distal margin setose; exopod short, narrowly lar, with few short spines on posterior margin; propodi
triangular,distallyacute,barely reachinglevel ofmesio- subequalinlengthto, about halfwidthofcarpus, with6
distal margin of proiopod. spines on posterior margin; dactyli biunguiculate, 2
Remarks. Poore (1984) clarified the diagnoses of ungui equallystrong; slenderaccessoiy spines onposte-
four seemingly closely related paranthurid genera that rior margin. Pleopod 1, rami tapering, distally rounded,
lack a seventhpereopod in the adult, ofwhich Califan- distolateral margins setose. Pleopods 2-4 typical of
thuraisone. ThefivepreviouslydecribedspeciesofCal- genus. Uropodwithbasisslightly shorterthanendopod;
ifanthuraarecharacterizedbyhavingpleonites 1-5 fused exopod three-fourths length of endopod.
and generally lacking dorsal folds marking this fusion Female: Pereopod 1,basisbearing5 stoutdistalsetae
(see Poore 1984:699). None ofthese possesses a short on anteriormargin; ischium with few setae on posterior
triangular uropodal exopod and an evenly tapering tel- surface; merus withanterodistalangle produced, bearing
son,norareanyofthemmatureatthesmallsize(1.6mm) stout seta; carpus with numerous setae on posterior
seen in C. minuta. surface, anterodistal angle produced into acute lobe;
Etymology. The specific epithet, the Latin for little propodus with palm separated from posteriormargin by
or tiny, refers to the small size (1.6 mm) ofthe adult. strong fringed spine, palm bearing 5 slender fringed
setae; dactylus bearing row of short fringed spines on
Family Stenetriidae posteriodistal margin, unguis about one-fourth length of
Stenetrium caicosensis, new species rest of dactylus. Pleonal operculum longer than basal
Figs. 6-7 width, subapically slightly pinched, distally rounded.
Color pattern. Red-brown scattering of chromato-
Material. HOLOTYPE, USNM 243476, male U 5.0 phores between eyes, onperconites 1 and 2,broadband
mm,PARATYPES, USNM 243477, 2males U4.3 - 5.0 on 3, absent on4, broad band on 5, scattering on 6 and
mm,5ovig.femalestl3.9-4.5mm, 11juvs.,GCRL1150, 7, broad basal band with lateral lobes on pleon.
1male4.3mm, 1 ovig. female4.8mm, FortGeorgeCay, Remarks. Of the four Caribbean species of Sten-
Neogoniolithon washings, 0.5 m, 18 Apr 1988. PARA- etrium having reniform eyes (See Kensley & Schotte
TYPE, USNM 243478, maletl5.2mm. CrabHole Cay, 1989:100), 5. caicosensis most closely resembles S.
Caicos Bank offPine Cay, 15 Apr 1988. bowmani Kensley, 1984, from Belize and Mexico, espe-
Description. Male; Body about3.5timeslongerthan cially in the shape of the cephalon and pleon. The two
greatest width. Cephalon with dorsolateral eyes large, species can easily be separated, however, by the color
well pigmented; anterolateral lobe acutely triangular, pattern(thechromatophoresaremoreevenlyanddensely
frontal margin faintly concave; rostrum rectangular, spread over the dorsum of S, bowmani), by the number
anterior margin truncate. Anterolateral lobes of pere- ofcoupling hooks on the maxillipedalendite (fourin S.
onites 1-3 acute,of4-7right-angledtorounded; postero- bowmani,sixinS.caicosensis),bytheshapeofpereopod
laterallobesofperconites6and7acute.Pleotelsonwider 1 of the male {S. bowmani possesses an expanded
thanlong,lateralmarginseachwith4serrations,posteri- propodus with a irilobedpalm, while S. caicosensis has
ormost forming strong tooth; posterior margin between abroadlobe on tlie posteriorsurface ofthe merus), and
uropodal bases gently convex. Antennule with basal bythemorestronglyproducedacuteanterodistallobe on
article widest and longest, article 2about halflength of the carpus ofpereopod 1 ofS. caicosensis.
3; flagellum of 11 articles, single aesthetasc on each of Etymology. The specific name is derived from the
8distalarticles.Antennaalmostaslongasbody,peduncle type locality, viz. the Caicos Islands.
article.s 1 and 2 short, subequal, latterwith setose scale,
article 3 very short, articles 4 and 5 slender, elongate, Acknowledgments
subequal, each longerthan 3 proximal articles together.
Mouthparts typical of genus, as figured, Maxilliped Collection ofthe material reported in this study was
enditewith6couplinghooksonmesialmargin. Pereopod sponsoredbytheOakleighL.ThomeFoundationthrough
1 of mature male with posterior surfaces of ischium, agranttoStephenSpotte, whoseinterestandsupportare
merus, carpus, propodus and dactylus bearing dense greatly appreciated. We thank Oakleigh B. Thome,
elongate setae; meruswith broad apically subacute lobe members and employees of the Meridian Club, and the
produced from distal half of posterior margin; carpus Turks and Caicos Government for support and encour-
subequal in length ofmerus (excluding posterior lo^); agement. Patricia Bubucis, Cherie S. Heard, Roy R.
propodus anteriorlength about 2.5 times greatest width, Manstan,JerryMcLelland,andStephenSpottehelpedin
withdistally directed spine-like process indistal halfof thefieldandprovidedothertechnicala.ssistance. Weare
posterior margin; dactylus curved, club-shaped, reach- gratefijl to Marilyn Schotte of the Smithsonian Institu-
ing to base ofpropodus, lacking distal claw or unguis. tion, who did much of the preliminary sorting and
2-7
Pereopods similar, meri with anterodistal angle identification ofthe samples. This is Contribution No.
producedandbearingstoutseta; carpi roughlyrectangu- 5 oftheTurks andCaicos CoralReefEcologyProgram.

Kensley and Heard
Fig. 7. Stentrium c€dco5ensiSy new species: A, pereopod 1 male; pereopod 1 female; C» pereopod 7.
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