Corallihalacarus chilcottensis, a new genus and species of marine mite from the Coral Sea (Acarina, Halacaridae)

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ZOOLOGICAL SCIENCE 16: 839-843 ( 1999) @1999 Zoologica lSociet oyf Japan
Corallthalacar cuhsilcottensis, a New Genus and Species ot
Marine Mitefrom the CoralSea (AcarinHaa:lacaridae)

JUrgenC. ottot

AustraEan institu toef ILdari Snceience ,PMB 5Tbvvnsvi" QeI,d 4810, Austrafia
ABSTRACFA new species and genus of marine mite, CoraMhalacaru schicottensis, is describe dfrom
Australi aI. toccurs in sandy deposi tasround Chilco tltslan ds,ome three hundred kilometres off the north-
eastern Australian coast, and can be distinguished from other marine mite species by having a flexibl eneck
between the idiosoma and the gnathosoma. Other unusual feature sof this species includ ea large median
claw on each tarsus, rigid lamella eon legs 11 a1nd IV, a very long apical palp segment and closely abutting,
fused or overlapping idiosoma lplates T.he new genus is most closely related to Mictognathu sNewell and
the new subfamily Mictognathina ies established to accommodate both genera,
anterior epimeral ptate ;GA, genitoana lplat eG;O, genit aolpening;
INTRODUCTION OC, ocular plate :P-2, P-3, P-4, palp segments designat eidn series
frem second most basal to apical one; PD, posteriordors apllate ;PE,
Although more than 900 species of marine mite posterio repimeral plate ;1-IV ,leg1to leg IV ;ads, adanai seta; ap,
(Halacaridhaavee)been described,new species are still
apodeme;co,collar;ts,fossaryseta;gb,gnathosomalbase;gp,gland
being discovere dat a constant high rate. For example, a two pore;pas,singleparambulacralsetae;d-pas,doubledparambulacral
week long collecting tri tpo Rottnes t1slan din Western Austra- setae; pc, pore canaliculus; pgs ,perigenit aseltae; re, rostrum; sgs,
li aresulted in the discover yof more than 80 species of subgenital setae; vs, ventral seta on tarsus ;m, solenidion on tarsus.
halacarid sf,rom which 62 new species have so far been
described(Bartsch1992a,b,1993a,b,c,d,1994a,b,1996a, RESULTS
b, 1997a, b) .This clearly indicates that our knowledge ot the
FamilyHalacaridaeMurray, 1877
halacari fdauna ,in particu tlhaart of the southern hemisphere,
SubtamilyMictognathinaesubfam. nov.
isstil1rudimentary.AstudyofthehalacaridfaunaofAustralia's
Guwasenanpxrdsepe ecereica aetprt$e lrwdBya.e aysv,hrt iaar Ifgvione ree,ua o rR ms srbHe eleweerochyieoefwe rrnsdeer ee vddog feiioo n srpn( lc,ayu Bolb aaarvnl erdesiairt cdneCsaygdl otc me,1rioh a 9raosn, e9pln dt6esSh cc itei)fe ha.sufs a Tranr htu oei1hfne sf4e ah ss 0ratsi uplim sdeonas ycsocictw euiaisryr s rsbie t enmndiatieilr ltwlnieyegn coPPmlra a-o lsL2 ce opalhmDnsyp aidal ltaea ttf gbPaep;uncl-tohyote3s sidctni ogefs m lr u:bDwaisii otonetpreerhda ds r;in,aaaor noll t fwlpepm irymaeltiam,hlaoxb rpitr nla seolnee sa ogproummiyvsoemerne retrslaealt p ta pPc ehiup-na tlg4iin ; acanolttnse e e ledvber eoseatnrettse tsr wtoadaaanels l ie bl lnnp fay opltusnrahse egot eaomexsdfsi.-
ddoecsucmreinbtees adn, T huneu spuarles esnp tepciaepser ,fwohiucnhd iosn p arret mooft eth iC ssheirliecso,tt rloas rtlraumm.e lTleale oT,fiebmioar eoa f,g aelnl uleag as nwdit ht ipbaiai e rwoift vhe netlraablor abtiepe acrttiicnua-te
lisaln caona dst,th.ree hundred kilometer osff the northeastern Austral- se t ae.7 )Ctlpa egwe fnousss: aMe iocnt aolgl ntaatrh$ uii snNceowneslplic, hueorue$. designated.
Remarks: Mictognathina esubfam. nov. is created here
to accommodate Mictognathu sNewetl and Cora"thalacasus
MATERIALS AND METHODS gen.nov.

Cora lsand, coliected by hand using SCUBA equiprnent, was
washed in a bowl of water and the supernatant decanted through a CoraIithalaca greuns. nov.
1OO um sieve. Mites retained in the sieve were cleared in lacti accid Diagnosis :Dorsum and venter with closely abutting or
and mounted permanently in PVA (Boudrea aunxd Dosse ,1963), fused dorsa land ventral plates. Anal opening positione ddor-
DaArrueas wtdirenapglosis aw ie)Ttr.heeed i mmn aetdaehseu r Mewuimtsehnet uasm c a omofef rT atrho epl iuiccdaii ldoQa su.Hoeomela onitsnyclplae una dnd CedtTh epo awvernnatsrtavlyipelle,sGanla ttho ogseonmiat ia olonpg eannidn gs,l etndheurs , ncoontn evcit$eidble t oi tn hvee nitdrialo svoimea wb.y
collar-likeextensionoftheanteriorepimeralplate.Abbreviationsused a "neckl consi$ting of flexib lmeembranous cuticle. Apical
in the descripti oannd illustrati aornes: AD, anterior dorsa pllate A;E, segment of palp longe rthan rest ef palp ,without a seta in
proxima lhalf ,Legs slender; tetofemora 11 1and IV with rigid
' Correspondi naugthor:FAX. [phone]. lamellae. Al ltarsi with paire dclaws and slightly shorter but
E-mail:[email protected],au heavie rmedian claw,
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7yt)e species : Coranihal aacrus chiicottensis sp. nov., here tibia el ,11 a1nd IV bot hbipectin asetteae of subequal length,
designated, on tibi a1 1one seta much longe rthan the other. Tars islightly
curved; claw fossa short and inconspicuou sA.l ltars wiith slen-
Coralfihalacar ucshilcottensis sp. nov. (Fig s1-.9) derpairedclaws,andslightlyshorterbutheaviermedianclaw,
Eipecimen sexamined: Holotype (S I051 39) : female ,Co ral Paire dclaws with minute accessory proces$ .Tarsus 1 with
Sea (Queensl aPnladteau), Chilcot tlsland ,16.56,51S three dorsa lsetae, pajr of doubled pas, pai rof ventral setae,
150.00.40E, 14 Septembe r1998, G. A. Diaz-Pulid oco,arse and dorsolater saollenidion (Fi g8). .Tarsus 1 1with three dor-
sand at 1O-15 m, on slope with algae, hydroid sand rubble. sal setae, pai ref pas singlets (th meedial one slightl yser-
Paratype (Sl0514 01 )f:emale ,data as for holotype. rated), an unpaired ventral seta, and a dorsomedia lsolenidion
Etymology :The name refers to the species' type locality. (Fi g9.), Tarsus 11 1with four dorsal setae (on eof these
female: tdiosoma :Length 578-582 pm <holot y57p8e); obscured by the articular lamella eof the tibi aar,rowed in Fig,
Dorsal and ventral plate sfinel ypunctate .AD with pair of 6) ,and pai rof pas, of which the later aolne is spur-like. Tar-
setae and pair of gland pores at its rounded anterior margin, a sus IV with same complement of setae as tarsus 11 1except
pai rof setae at the anterolateral corners of the plat eand two with only three dorsa lsetae. The medial of the two distal
pair sof apodemes in deeper cuticular layer $(Fi g1.) .OC fossar ysetae on tarsus 1 1much fine rthan the later aolne.
tapering posterior lwyit;h two pores and a minute pore canali- Malo: Unknown,
culus lateral alnyd several minute pore-li kdeepression sme- Rematks: The most conspicuous character that distin-
diall PyD. ovoid; with two pair sof setae and pai rof glan dpo res. guishes Corallihalaca rcuhiscottensis sp. nov. from all other
AD, OC, and PD in deeper layers separated from each other known halacarid si,s the presence of a membranous flexible
by a narrow $trip of membranous cuticle .In upper layer sPD "neck" between gnathosoma and idiosoma .It is unclear
anteriorly with a fla rtim which overlaps the AD and obscure$ whether this "neck" is constantly exposed in the way i thas
the membranous cuticle in deeper layers A.D with a similar been found on the holotyp eand paratype ,or whether i tcan
rim on either side which overlaps with OC, Ventra lplate ssepa- be retracted, Judging from the delica ntateure of the membra-
rated only by a delicat feurrow ,not by membranous cuticle, nous structure, which is in stark contrast to the otherwise well
AE anteriorl ywith a collar-like extension which is divided $clerotized idio$oma ,i tappears unlikely that the "neck" is con-
anteriorly int otwo overlapping lobes {Fi g2,) ;three pair sof stantly protrude dT,he wrinkles on the "necW' and the pres-
ventrai setae (on especimen with three ventral setae on one ence of an apically expandable collar int owhich the "neckl
side, but only two setae on the other side); several conspicu- could be retracted, furthe $rupports thi shypothes iTsh,e pur-
ous apodemes in deeper cuticula rlayer sL,eft and right parts pose of the "neck" is currently unknown,
of dorsat AE fused, PE dorsall fyused to AE, with one dorsal Other highly unusual characters of C. chilcottensis are
and three ventral setae; anterior to dorsa iseta with a foveate the positi oofn the anal opening dorsa lto the genit aolpening,
and punctat eareola; po$terio tro areola smooth, GA with two the presence of an enlarged median claw on the tarsi ,the
pair sof pgs, one of these inserte danterior to GO the other extremely elongated P-4 with no setae in the proxima lhalf,
pai rat $ame leve las GO. One pair of sg$ on genital sclerites, and dorsa land ventral non-cerotegumental spiky iamellae on
Anal opening and GO bot hpositioned caudally, anal opening legs 11 1and IV, Most of these characters are unique to this
dorsa lto GO. genus. The only exception is the enlarged median claw on
Gnathosoma S]lender s;eparated from idiosom aby mem- the tarsi which otherwise occurs in the rhombognathine
branous, flexibl eand wrinkled cuticle {Fi g1.) .Gnathosomal genus Metathombognathus where i tis most like lay conver-
base finel ypunctat eco,nspicuously elongated (Fi g3),, Ros- gence.
trum slightly Ionge rthan gnathosomal base; with pai rof fine Several other unusual characters are not unique to
setae at it sbase, a pai rof setal sockets in anterior half (setae Cora1llhalaca tbuust are shared with the genus Mictognathus
most like lbyroken off), and two pair sof minute setae at tip, which is known from two species (M .werthe"oides Newell,
Paips inserte dlaterall yt;our-segmented; P-2 with a seta an- 1984, and M. secundUs Bartsch ,1992c), Mictognathu salso
terior lPy-;3 without a seta; P-4 longe rthan rest of palp ,with has dorsall fyused anterior epimeral plate sov,erlapping dor-
one slender seta in dist ahlal afnd one short tapering seta and sal plates c,losely abutting or fused ventral plates e,laborate
two short blun tsetae apically. Chelicer acllaw short, with sev- articular lamella eon genua and tibia er,educed claw fossae,
eral teeth. a relatively long apical paip segment with only one seta in
Legs: Slender ,Tibia eapically swollen (Fig s4-,7). addition to the minute apical setae, and a pai rof bipectinate
Telofemora ll land IV dorsal[ yand ventrally drawn out into setae on all tibia eO.n basis of these similarities Adictognathus
large rigid and spiky lamella e(Fig s6., 7), ln addition, and CoraiLinataca raures here regarded as each others clos-
telofemor ag,enua and tibiae with elaborate articular lamel- est relatives.
lae .Basifemor acarrying cuticular spines, one on basifemora Mictognathu swas previousl pylaced in the Halacarinae
1and 11 ,three on basifemur Il land two on basifemur IV. (se eBartsch ,1992c; Abe, 1998), which is a very heterog-
Basifemora and telofemora 1 and 1 1foveate (Fig s4., 5), enous group as i thas been used extensively to accommo-
Chaetotaxy (trochanter M--t2i-b5i-a4)- :5l ,l1-2-4-4- 5l,l l1-2- date genera that simply cannot be assigned to any other
2-3-4, IV 1-2-2-3- 4A.l 1tibia weith pair of bipectina tseetae; on subfamilies ,However, to achieve a more homogenous sub-
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New Genus and Species of Marine Mite 841
GO
F1iO gO sp . m1 .- 2A .D , Caontrearlifoir dhaotrascaa plr lcuhasitle cA;oEt,te annsties srpi.o r neopvi,,me rfaelm apllea: 1t , eGl;Adi, ogseonmia taonadn ag ipnlaattheo ;GsOo,m ag, ednoirts aao lplveineiwn;g ;2 , OlCd,i oocuslaorm avpe,lntartale ;P Dvi,e w.po sStcearli eo bdraorrss =al
plat eP;E, posterio repimeral plate ;ads, adanal seta; ap, apodeme; co, collar; gb, gnathosomal base; gp, gland pore; pc ,pore canaliculus; ro,
rostrum; pgs, perigenit aselta; sgs, subgenita1 seta.
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Figs. 3-9 , Coralnvialac achriulcsottensis sp. nov., female: 3, Gnathosoma, ventrolateral view (sca lbaer=50 pm): 4, Leg 1 ,ventromedial view
<sca lbear=1OO pm); 5, Leg 11 ,ventromedial view (sca iase Fig .4); 6, Leg li lv,entromedial view (sca lase Fig 4.); 7, Leg IV ,ventromedial view
(sca lase Fig ,4); 8, apical part of tarsu s1 ,ventrolateralview (sca lbaer=25 pm); 9, apical part of tarsus 11 ,ventromedial view (sca lase Fig .8) ,d-
pas ,doubled parambulacra lseta; fs ,fossary seta, gb, gnathosomal base ;mcl, median claw; pas ,parambula rcal seta; ro, rostrum; v, ventral seta;
to, solenidion,
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New Genus and Species of Marine Mite 843
famil yHalacarina ei tappears benefici atlo remove some of Bartsch 1 (1993 b"HPa)iraoccaereuds i(nHgaslacari AdcaareD, from south-western
tbhe e maossriegn eudnus uatlo gotehneerr a bfertotm e trhde eHfailnaec dasruibfnaa meii fltiheesy. caAns Alluosgslitcaranai lWdWie,o asrI.ktn sehro nApu:s tTrhael iM a aEo"rdfi tbnhyee F FEFli oWfret al hllannstd, De lrF nWaaautlnikaoe n rMoa, falH r RKiointret kBnmieaosn-t
Mictognathus resembles CoraIiihataear umosre than any and R Lethbridge, Western Australia Mnuseum, Perth ,pp 45-71
other halacarin geenus i tis here removed from the Halacarinae Bartsc 1h (1 993c) Arenicolou sHalacarida e{Acar fir)om South-West-
and together with Corallihaiac palraucsed in a new subfamily em Austral ilan ,"Proceedings ot the Fift hlnternation aMlarine
Mictognathinae, Biologi cWaolrkshop :The Marin eFlora and Fauna of Rottnest
lsland W,e$tern Australi aE"d by FE Wells, Dl Walker, H Kirkman
and R Lethbridge ,Western Australia nMuseum, Perth ,pp 73-
103Bartsch
ACKNOWLEDGEMENTS
1 (1993 dA} new species of Austratacaru s(Halacaridae,
I thank the Australia nBiologic aRlesources Study (ABRS }for Acari )from Southwestern Australi aZ,ool Jah de Syst 120: 65-70
fundingthepresentproject,theAustralian1nstituteofMarineScienceBartsch 1 (1994 aT)he genus Simognathus (Acar ii Halacaridae).
for providin gfacilit iaensd laborator sypace, and Peter Doherty and Descript ioof nsix new species trom southern Australi aand a
GCuhiilllceortmtl osDliaanzd-.P1ualmid fopoar prrtoivciudlina gmgrerla ywtitehf tuthloe t1y1psee sBpaerctismecnhsto rfhreorm B ar ttasbcu l1h a<r1 k9e9y 4t ob Ca)lol psipedcioesg.na Atcha u(rsoHlaolgia a3c5a: r1i 3A5dc-aa1rei5)2: trom Western
suggestion of a clos e relationship betw een Mi ctognat hus and Australi aD.escriptio onf twelve species of the gibbus group, Rec
Corallthalacaraunsd herand twoanonymous retereesforcomments West Aust Mus 16: 535-566
on the manuscript . Th is p ubl ica t iios cnontrib ution 941 of the Austra- Bartsch l (1996 aHa)lacarine s(Aca Hraila:caridae )from Rottne slts-
lia nlnstitu otfe Marine Science. land, Western Australia :the genera Agauopsis Viets and
Halacaropsi sgen, nov. Rec West Aust Mus 1 8: 1-1 8
Bartsch 1 (1996 bv)aVerthe laLmapliata n. sp,, a new psammophileus
REFERENCES haiacaridmite(Acari:Halacaridae:Copidognathinae)fromWest-
ern Australi aA,carologi a37: 275-280
Abe H (1998 R)hombognathin Meites T.axonomy, Phylogeny, and Bartsch 1 (1996 cH)alaoarida e(Aca rfrio)m the Great Barrie rReet.
Biogeography ,Hokkaido Unive rsity Press .Sapporo p,p 219 Descriptie onf a new species of Cepiciognat hPurso,c R Soc Vic
Bartsch 1 (1992 a)Phacacarus fiaveltu sgen. et spec. nov. 108:57-62
(Copidognathi nHaael,acaroidea ,Acari), eine Meeresmilbe auf Bartsch 1 (1997 aAr)hodeoporus {Aca rHia:lacarid aier)om Rottnest
Kalkalgen .Zool Anz 228: 21 2-219 lsland ,descripti oonf three new species. Acarologi a38: 265-
Bartsch 1 (1992 bT)wo new species of the genus Brabyagaue 274Bartsch
(Halacaroi Adcearai, )from the southern lndia nOcean. Cah Biol 1 {1997 bA) new species of the Copiclognat htruiscomeatus
Mar 33: 433-440 group (Acar Hia:lacaridae )trom Western Australi waith a review
Bartsch 1 { 1992c) Mictogna thus secundUs, a psammophilous halacarid of thi sspecies-group. Specie sDiversi t2y: 155-166
mite {Aca r: iHalacaridae )A.carologi a33: 85-89 Boudreaux HB, Dosse G (196 3T)he usefulness of new taxonomic
Bartsch 1 {1993 aR)hombognathine mites {Halacari Adcaarei, )trom characters in female sof the genus levanychus Dufour (Acari:
Rottnes tlsland ,Western Australi aI.n "Proceedings of the Fifth Tetranychid aAec)a,rologi a5: 1 3-33
lnternation Maalrine Biologic aWlorkshop: The Marine Flora and Newell, 1M (1 984) Antarct Hiaclacaroidea .Anta rctic Research Series
Fauna of Rottnes tlsland W,estern Australi aE"d by FE Wells, Dl 40: 1-2B4
Waiker, H Kirkman and R Lethbridge ,Western Australian
Museum, Perth ,pp19-43 (Receiv eFdebruary 19, 1999 1 Accepted Apri l28, 1999)
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