A new cavernicolous shrimp in Pycnisia Bruce, 1992 (Crustacea: Decapoda: Caridea: Atyidae) from northwestern Queensland

5 Pages·2003·1.4 MB·English

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ANEW CAVERNICOLOUS SHRIMP IN PYCNISIA BRUCE, 1992 (CRUSTACEA:
DECAPODA: CARIDEA: ATYIDAE) FROM NORTHWESTERN QUEENSLAND
HIROSHI SUZUKI AND PETERJ.F. DAVIE
Suzuki,H.&Davie,P.J.F.2003 0630:AnewcavemicolousshrimpinPycnisiaBruce, 1992
(Crustacea: Dccapoda: Caridea: Atyidae) from northwestern Queensland. Memoirsofthe
QueenslandMuseum 49(1):447-451. Brisbane. ISSN 0079-8835.
A new cavemicolous shrimp, Pycnisia hunyip is described from Forbes Inferno Cave,
,
Riversleigh, LawnHillNational Park,northwesternQueensland.Pycnisiaisdifferentiated
from all otheratyid genera by its robust pereiopods 3-4. Pycnisia hunyip is distinguished
from the only known congener, Pycnisia raptor Bruce, by the shape ofthe rostrum and
telson.ThisistheseventhspeciesoftroglophilicatyidfromAustralia. Pycnisia,Atyidae,
Caridea, Queensland, newspecies, troglobite.
Hiroshi Suzuki, Aquatic Resource Science, Faculty ofFisheries, Kagoshima University,
4-50-20 Shimoarata, Kagoshima 890-0056, Japan (e-mail: suzuki@
fish.kagoshima-u.ac.jp) PeterJ.F.Davie, QueenslandCentreforBiodiversity’, Queensland
Museum, POBox3300,;SouthBrisbane4101, Australia; 15April2003.
The first Australian subterranean shrimp was SYSTEMATICS
described in 1960, and anotherfivespecies have Family AYIDAE De Haan, 1849
beendescribed in indigenousSty’giocatisHolthuis, Genus Pycnisia Bruce, 1992
1960,ParisiaHolthuis, 1956,PycneusHolthuis, Pvcnisia bunvip sp. nov.
1986, andPycnisia Bruce, 1992. All have so far (Figs 1-4)
beenfoundonlyinwellsorcavesinnorthwestern MATERIAL.Holotype:QMW26722, 9 (7.0mm),Forbes
Australia. These troglophilic shrimps have Inferno Cave, Riversleigh, Lawn Hill National Park,
reduced eyeswithout pigments, and no carapace northwesternQueensland, in shallow subterraneanpools,
S. Williams and B. Ehrlich, 22/6/1994. Paratypes:
spines (except for an antennal spine in QMW26723, 9 (2.6mm), data as for holotype.
Stygiocaris).ThepreviouslymonotypicPycnisia QMW26724, 9 (specimendamaged),dataasforholotype.
was established for P raptor because of its QWiMlWli2a6ms7,2154,/6/19993(.6.Q2MmWm,2)6,72s5a,me9lo(c3a.t7imomn,,),codlalt.a aS.s
unique remarkably robust pereiopods. Pycnisia forprecedingspecimen.
hunyip sp. nov. is the seventh species of ETYMOLOGY.Amythicalpredatorycreaturesaidtolive
troglophilic atyid from Australia. inAustralianfreshwaterpools. Anouninapposition.
Reproductive isolation leading to incipient DIAGNOSIS. Rostrum small, short, reaching to
speciation can be expected to occur amongst only half length ofeyes, but projecting beyond
freshwater crustaceans occurring in widely pleyvreilfoormf,ilnafcerkiionrg poribgimteanlt.anTgelles.onEyweisthroendeucpeadi,r
isolatedfreshwatercavesystems.Duringsurveys ofdorsalspines(2pairsinparatypes)andonepair
oftheForbesInfernoCave,Riversleigh,LawnHill ofsub-dorsal spines, 7 spines (6-8 in paratypes)
National Park, northwestern Queensland, onposteriormargin.Pereiopods 1-5with l, 1, 1,
and 2 setobranchs, respectively.
conducted in 1993 and 1994, unusual specimens
ofa Pycnisia species were found. The shape of DESCRIPTION. Small species (postorbital
carapace length <7.0mm), but largest recorded
the rostrum, and structure ofthe telson ofthese Australian troglophilic atyid species. Carapace
shrimps indicate that they represent a new thin, flexible, smooth, without spines or setae
species that is herein described and illustrated. (Fig. 1); rostrum small, acute, with short, faint,
dorsal ridge, reaching beyond level ot inferior
The types are deposited in the Queensland orbitalanglestohalflengthofeyes(Figs 1,2A-B,
Museum, Brisbane (QM). Measurements are of 3M); pteryogstomian angle broadly rounded (Fig.
post-orbitalcarapacelengthinmillimeters(mm). 2B).
448 MEMOIRS OF THE QUEENSLAND MUSEUM
incisor process short, broad, with 4
stout marginal teeth. Maxillula with
slender palp, with several setae
distally (Fig. 3F); upper lacinia
narrow, with numerous short
spinuleson innerand distal margins;
lower lacinia subrectangular with
short setae on inner margin. Maxilla
(Fig. 3G) with slender palp con-
cealed behind endites, basal endite,
coxal endite, and scaphognathite
having20multidenticulatelongsetae
on posterior end. First maxilliped
(Fig. 3H) with simple tapered palp,
notreachingtodistalmarginofbasal
FIG 1.Pycnisiabunyip, sp. nov., 9 holotype(QMW26722), lateral endite; basal endite lamellar,
view. Scalebar=5mm. elongate, medial margin densely
fringedwithsetae;coxalenditestout;
Abdomen smooth, pleura of abdominal exopod well developed, caridean lobe large,
somites 1-5 rounded (Fig. 1). Telson slightly broad,taperingdistally;epipodvestigial. Second
shorterthansixthabdominal somite,rectangular, maxilliped(Fig.31)withwell-developedexopod,
with 1 pair of dorsal spines (2 pairs or 4 withnumerouslongplumosesetaeondistal half,
irregularly arranged dorsal telsonic spines on and shorter, thicker setae placed about quarter
paratypes) and pair ofsmall subdorsal spines distance from base; small rounded epipod with
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near posterolateral comer (Figs 2C, 3N,0); multilamellar podobranch. Third maxilliped
dorsal spines placed slightly behind middle of reachingbeyondantennularpeduncle,stoutwith
telson, second pair, if present, placed close to small single arthrobranch (Figs 1, 3J); exopod
posterolateral margin (Fig. 3N,0); posterior well developed, with long setae distally; epipod
margin broad, faintly biconvex, with 7 plumose strap shaped.
and 5 simple setae (6-8 plumose setae in Pleurobranchs present on pereiopods 1-5,
paratypes). exopods on maxillipedsonly, and epipodson all
Eyes reduced, pyriform, devoid of pigment, maxillipeds and pereiopods 1-4.
cornea rounded (faint papilla on tip ofeyes in Firstpereiopodshort,robust,chelate(Fig.3K);
small specimen with postorbital carapace length chela about 1.5 x carpus length, palm ofchela
of2.6 mm) (Figs 1,2A-B. 3M). swollen, posteriorly expanded, longer than
Antennularpeduncle stout, slightly exceeding dactylus; fingers robust, tapering, curved,
distal margin ofscaphocerite (Figs 2A, 3A,M); distally with tuft ofsparse setae, claw-like tip;
proximal segment broad, with stylocerite acute, carpus expanded distally, distodorsal margin
laterally divergent, reaching beyond middle of deeply excavate; merus subequal to chela,about
proximal segment, outer anterolateral angle 1.5 x carpus length, slightlybroadeneddistally;
weaklyforwardlyproduced(acutelyproducedin coxastout,withstrap-likedistallyhookedepipod
young paratype), medial margin relatively andone setobranch. Second pereiopod (Fig. 3L)
straight; intermediate and distal segments sub- with chela, chela about 0.9 x carpus length;
cylindrical, medial margins setose; antennular palmfeeblyexpandedproximally,faintlybowed;
flagella slender, subequal. dactylus as long as palm length, unarmed,
Antennal scaphocerite (Figs 2A, 3C,M) well otherwise similar to first pereiopod; fingers
subequal, stout, pigmented distally, fixed finger
developed, broad; outermargin with large broad similar to dactylus; carpus feebly expanded
acute distolateral tooth; inner margin convex; distally, distodorsally feebly excavate; merus
b3lBu)ntlwyitrhoouuntdesdpidniestsa;llyf;laagnetlelnunmallpoendgun(cFlieg.(Fi1g)., afibrostutpe1r.e5ixopocda,rpwuistlhensgttrha;p-cloixkeaseipmiiploadrtaontdhaotnoef
distinctly longerthan whole body length. setobranch. Third pereiopod very robust (Figs
Mouthparts similar to P. raptor, Mandible 2D,4A); dactylusstout, taperingdistally, unguis
without palp (Fig. 3D-E); molar process small, demarcated with fringe ofsetae, ventral margin
occlusal surface with marginal setal fringe; with 9 stout, moveable spinules (Fig. 2E);
ANEW SPECIES OF PYCNISIA 449
FIG.2.Pycnisiabunyip sp.nov., $ holotypc(QMW26722):A,dorso-frontalviewofcarapace;B,latero-frontal
,
view ofcarapace; C, dorsal view oftelson; D, left thirdpereiopod; E, dactylusofleftthirdpereiopod; F, left
fourthpereiopod. Scalebars= mm.
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propodusabout0.9x (range0.8-1.1 inparatypes) 1.5 x (1.7 in paratype QMW26725) carpus
carpus length, slightly bowed, ventral margin length; ischium andbasis normal; coxawith two
with numerous short, stout, moveable spinules; setobranchs butwithout epipod.
carpusslightlyconvexventrally,with singlerow
o21.f.00s--etaemedially;merusveryrobust,about 1.9X attFeirnsutatpeldeoepnoddop(oFdi.g.S4eDc)onwdith(Fisgl.en4deEr), tdoistfailfltyh
s(ercatnigoen,12.9.-82x.7(inrapnagreat3y.p8e-s5).0cainrppuasralteynpgeths,)olvoanlgeirn aplpepoepnoddisxsiimnitlearrn,a.endUorpoopdodnaolt aptrtoentuoaptoedd, wwiitthh
than greatest width, dorsal and ventral margins
posterolateral angle acute (Fig. 4F); diaeresis ot
convex; ischium short, distal half of ventral exopod distinct, but incomplete; endopod
border with rounded patch ofdense setae; basis
slightly shorterthan exopod.
short,robust;coxarobust,withstrap-likedistally
hooked epipod and one setobranch. Fourth Color In Life. Photographs show a yellow
pereiopod (Figs 2F, 3B) robust as third carapace with colour extending into anterior
pereiopod; propodus subequal to carpus (range abdomen, probably representing the hepato-
1.3 in paratypes); merus about 1.9x (range pancreas,andpossiblyovary,beneath.Abdomen
2.9 in paratypes)carpus length,2.9x (range mostly transparent.
3.3-7.0 in paratypes) longerthan greatestwidth;
otherwise similar to third pereiopod. Fifth REMARKS. This new species, P. bunyip, is
pereiopod slender (Fig. 4C); dactylus slender, similar to P. raptor in having reduced eyes
feebly tapering distally, unguis faintly without pigmentation, a small rostrum, and
demarcated; propodus about 1.7 X (1.6 in robust pereiopods. However, in P. bunyip the
paratype QMW26725) carpus length, rostrum reaches slightly past the level of orbital
ventrolateral border with row of stout setae; angle (shorter in R raptor), and the telson has
carpus with small distodorsal lobe; merus about onlyoneortwopairsofdorsalspinesandonepair
450 MEMOIRS OF THE QUEENSLAND MUSEUM
antenna; C, scaphocerite ofleft antenna; D, ventral view ofmandible; E, dorsal view ofmandible; F, left
maxillule; G, leftmaxilla; H, First maxilliped; I, second maxilliped; J. third maxilliped; K, Firstpereiopod; L,
secondpereiopod.M-N, 9 paratype(QMW26723);M,dorso-frontalviewofcarapace;N,dorsalviewoftelson!
O, 9 paratype(QMW26724),dorsal viewoftelson. Scalebars= 1mm.
ofsubdorsal spines (four pairs ofdorsal spines (Bruce, 1992; Holthuis, 1986; Williams, 1964).
and one pairofsubdorsal spines inP. raptor). Thesespecies,alongwithP.bunyip arethoughtto
,
The setobranch and multidenticulate scapho- havepassivegill-cleaningmechanismsasoccurin
gnathite setae are known to have an important other atyid species. However, Stygiocaris
gill-cleaning role in some caridean shrimps lancifera and S. stylifera have no long setae on
(Bauer, 1981, 1989; Suzuki & McLay, 1998). the posterior portion of the scaphognathite
Pycnisia bunyip has one or two setobranchs on (Holthuis, 1960). These two species are thought
the coxae of the pereiopods, and 20 multi- tohaveeitheranactivegill-cleaningmechanism
denticulate scaphognathite setaesimilarto other
atyid species. Four Australian troglophilic usingapereiopodsetal brush,oradifferentform
shrimps, Parisia gracilis P. unguis Pycneus of passive gill-cleaning using branchiostegal
morsitans and Pycnisia, raptor a,lso have setae (Bauer. 1998; Batang & Suzuki, 2000).
,
setobranch and several long multidenticulate Future study of gill-cleaning mechanisms of
setae clearly belonging to the scaphognathite cavernicolous shrimps may be useful for
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A NEW SPECIES OF PYCNISIA 451
FIpGe.re4i.oPpyocdn;iDs,iafibrustnypilpco,psop.d;noEv,.,se$copnadraptlyepoepo(dQ.MSWc2al6e7b2a5r)s:=A1,mtmh.ird pereiopod; B, fourthperciopod; C, fifth
understanding adaptive selection pressures and grooming in Crustacea. Crustacean Issues 6.
phylogenetic relationships. (A.A. Balkema: Rotterdam).
1998. Gill-cleaning mechanisms of the crayfish
DISTRIBUTION. Only known from the type Procambarus clarkii (Astacidea: Cambaridae):
locality. experimental testing of setobranch function.
InvertebrateBiology 117: 129-143.
ACKNOWLEDGEMENTS BRUCE, AJ. 1992. Pycnisia raptor, anew genus and
Weareverygrateful toStefan Williamsforthe sDpeeccaipeosdoaf:prAetdyaitdoarey)trfogrloombicNosrhtrhiemrpn(CAruussttraacleiaa:.
collectionanddonationofthespecimens,andthe InvertebrateTaxonomy6:553-566.
Japanese Government for a travel grant to H. HOLTHUIS, L.B. 1960. Two new species of atyid
Suzuki. A.J. Bruceand XinzhengLi arethanked shrimps from subterranean waters of N. W.
fortheiruseful commentson themanuscript. Australia (Decapoda Natantia). Crustaceana 1:
47-51.
LITERATURE CITED 1986. A new genus and species ofr sutbterranean
BATANG,Z.B.&SUZUKI,H.2000.Gillstructureand shrimp from Western Australia (Crustacea:
gill-cleaningmechanismsoftheredclawcrayfish Decapoda: Atyidae).ZoologischeMedcdelingen,
Cherax quadricarinatus (Decapoda, Astacidea, Leiden60(7): 103-1 1.
Parastacidae). Journal of Crustacean Biology SUZUKI, H. & McLAY, C.L. 1998. Gill-cleaning
BAUE2R0,(4)R:.T6.991-978114..Groomingbehaviourand morph- Amteycihdaanei)samnsdocfomPpaarraitsyoanscwuirtvihrossetvreinss(pCeacriiedseao:f
ology in the decapod Crustacea. Journal of Japanese atyid shrimps. Journal of Crustacean
198C9r.usDtaecceaapnoBdioclrougsyta1c:ea1n53-g1r7o3o.ming: functional WILLBIiAoMloSg,y 1W8.(2D).: 215936-42.70.Subterranean freshwater
morphology, adaptive value, and phylogenetic prawns (Crustacea: Decapoda: Atyidae) in
significance. Pp. 49-73. In Felgenhaucr, B.E. et Australia. Australian Journal of Marine and
al. (eds) Functional morphology offeeding and FreshwaterResearch 15: 93-106.