Table Of Content.
Memoirs ofthe MuseumofVictoria 54: 171-178 (1994)
MARICOCCUS BRUCEI, AN UNUSUAL NEW GENUS AND SPECIES
OF SPHAEROMATIDAE FROM SOUTHERN AUSTRALIA
(CRUSTACEA: ISOPODA)
By Gary C. B. Poore
DepartmentofCrustacea, Museum ofVictoria, 71 VictoriaCrescent, Abbotsford,
Victoria 3069, Australia
Abstract
Poore, G. C. B., 1994. Maricoccusbrucei, an unusual newgenus andspecies ofSphaero-
matidae from southern Australia (Crustacea: lsopoda). MemoirsoftheMuseum ofVictoria
54: 171-178.
A new monotypic genus is diagnosed, the first among Sphaeromatidae with complete
fusion ofpleonite I to the remaining pleonites. It belongs to agroupofdynameninegenera
inwhichthefirstpleopodsareoperculiform,thefirstpleonalsterniteis long,andthemandibu-
lar incisor is unicuspidate. The new genus is exceptionally flattened, more than in species
ofJulettaBruce, 1993 andMarguerittaBruce, 1993 whichitresembles. Itdiffers fromthese
two in the possession offalcate percopodal dactyli.
Introduction ventral rostrum between antennae; eyes small,
The sphaeromatid subfamily Dynameninae lateral, visible in both dorsal and ventral views.
Bowman is characterised principally by the pres- Coxae 2-7 fused to tergite, laterally expanded,
enceofthickened folds on both rami ofpleopods interconnected by coxal keys, visible ventrally;
4 and 5. With about 35 genera it is the largest coxa 7 reaching to lateral margin of body.
subfamily ofthe Sphaeromatidae. Six ofits gen- Pleonite 1 completely fused to remaining
era are associated in what seems a monophylet- pleonites, indicated mid-lateraily by short slit; all
ic clade united by the possession of operculate pleonites fused to pleotelson, 1 suture probably
or semioperculate pleopods pleopod 2 with between pleonites 5 and 6; pleotelsonic apex
endopod very much longer th1a,n exopod, and a entire, without foramen orexitchannel. Pleonite
complete sternite on pleonite 1. The six are: 1 sternite long, with plate between pleopods I
Ischyromene Racovitza (Harrison and Holdich, Epistome (fused frontal lamina and clypeus)
1982); Amphoroidea Milne Edwards (Baker, broad, notextending between antennae 1. Anten-
1908); Amphoroidella Baker (Harrison, 1984); na 1 peduncle not flattened, article 2 produced
Cymodocella Pfeffer(Brandtand Wagele, 1989); distally. Mandibularincisorunicuspidate; lacinia
Juletta Bruce; and Margueritta Bruce (Bruce, mobilis absent; spine row of prominent slender
1993). Other undescribed genera are known (N. truncate spines; molar process blunt, not orna-
L. Bruce, pers. comm.) and otherspecies may be mented. Maxilla 2 outer lobe short, with 1 seta.
assigned to the group when their pleopods have Maxillipedal endite with clubbed setae mesially;
been described. The monophyly ofthecladeis as palp articles 2-5 without lateral setae, with
mesial setae; articles 3 and 4 weakly lobed.
yet untested.
A new similar genus and species from south- Pereopod 1 shorterthan 2-7, each with falcate
ern Australia, Maricoccus brucei, is here dactylusaboutas long aspropodus. Penespaired
on posterior margin ofpereonite 7, not reaching
described.
Material is lodged in the Australian Museum, pleopods 1.
Sydney (AM), Queensland Museum, Brisbane Pleopods 1 and 2 togetheroperculiform; pleo-
(QM), Museum ofVictoria, Melbourne (NMV), pod 1 short, exopod weakly indurate; pleopod 2
and SouthAustralian Museum, Adelaide(SAM). endopod weakly indurate, much longerthan exo-
pod, concealing remaining pleopods. Pleopod 3
Maricoccus gen. nov. exopod withouttransversesuture. Pleopods4and
5 with thickened ridges on both rami; exopods
Type species. Maricoccus brucei sp. nov. without suture; pleopod 5 exopod with 2 scaled
Diagnosis. Body strongly flattened, smooth; lobes. Pleopods 1-3 only with plumose margin-
pereonites6and7 withoutdorsal processes. Head al setae. Uropods lamellar, meeting in midline
strongly flattened, anteriorly produced, with posteriorly, rami not reduced.
GARY POORE
172 C. B.
Female. Mouthparts not metamorphosed. culinae. Dynamene Leach is the only sphaero-
Oostegites present on pereopods 2-4, overlap- matid genus which has been shown convincing-
pinginmidline.Bodyand appendagesasin male. ly to lack appendices masculinae (Holdich and
Harrison, 1980) andthetruegeneric condition is
Etymology. From the Latin mare (the sea) and uncertain.
Coccus (a Linnean genus ofscale insect) allud-
ing to the origin and shape of the type species Maricoccus brucei sp. nov.
(masculine).
Figures 1—4
Remarks. Maricoccus is the first-recorded NW
Materialexamined.Holotype.Vic, sideofHentyReef,
sphaeromatid withcomplete fusion ofpleonite 1 Mounts Bay, Apollo Bay (38°47.0'S, 143°40.5'E), 3 May
to the remaining pleonites and telson. The usual 1988, 18m, redalgaeon boulder, R.T. Springthorpeand P.
sphaeromatidcondition isathree-partpleon: very B. Berents,AMP41376(6*,4.6mm,with 1 slide).
shortfreepleonite 1 whoseepimerado notreach Paratypes. Victoria. Type collection. AM P4I840 (non-
the lateral margin of the body; fused pleonites ovigerous 2, 3.3mm; 6 mancas, 1.5-2.7 mm). Typelocali-
AM
2-5 with epimera variously indicated laterally: ty but on bryozoan lOrthoscuticella, P41373 (manca,
andpleotelson (pleonite 6plustelson). In Maric- 2.3mm).LaurenceRocks,Portland(38°24.0'S, 141°40.1'E),
occus there is no indication ofpleonite 1 dorsal- 3B.0BAeprren1t9s8,8,A2M3mP,41o3n4r5ed(oavliggaeer,oRu.sT2.,S4pr.i6nmgmt;hor2pemaanncdasP,.
ly orlaterallyandtheremaining pleotelsonic unit 1.6,2.1mm). 15kmS ofPortFairy(38°32.0'S, 142°28.6'E),
bears only onelateral suture,possibly indicating 20Nov 1981,52m,mediumsand,R. Wilson(stn BSS-187),
the suture between pleonites 5 and 6. NMVJ13266(non-ovigerous 2,3.7mm).
The features shared by Maricoccus and the Tasmania. 14km SW of Currie, King I. (40°00.7'S,
dynamenine Ischyromene-group of genera are 143°49.9'E),46m,finesand,sled,R. Wilson(stnBSS-197),
exposed and thickened proximomesial triangle NMVJ26276(manca,2.3mm).
of pleopod endopod, endopod of pleopod 2 South Australia. E side of Wright I., Encounter Bay
muchlonger1than exopod, andthecomplete ster- (35°35'S, 138°37'E), 10 May 1988, on bryozoan, 12m, N.
Holmes(QMW18928,non-ovigerous 2,3.4mm).0.8kmS
Inintdeivoifdpulaelolnyi,teth1ewsiethchaamreadcitearlspomsateyriboerpsreoecenssi.n o1f38H°e3n1l'Ee)y,B1eJaacnh1J9e8tt5y,,fArdoemlaAimdpeh,ib1.o4lkismaonftfasrhcotrieca(c34o°m4m5'uS-,
some other sphaeromatid genera but investiga- nity, 6-7 m, S. M. Clarke, SAM C5509 (juvenile, 4.4.mm,
tion oftheir distribution is beyond the scope of with 2 slides), SAM C5510 (2juveniles, 3.1mm), NMV
this contribution. J14028(juvenile,4.5mm,with 1 slide). Beachport, Snapper
o2,pPearlsceiuotlpuiaoftdoior1nmivosenrvlyeyrdyiinfsfcheoorrmetbntiinnfarMtoaimorniotcwhoiectrchugespnleaernoadpooidfs (Prseoetifnn,tCG(R.3U7C°.S29BT..39P'0oS),o,r1Ne3M9a°nV5d9R.J.62E0S).4,2W66ilm(s,jounbv,ernoi1wl4enM,aa2l.yg6ame19mo9)n0.,liSmCesUtBonAe
thegroup. Within theIschyromene-group,Maric- Description. Male.Body 1.5 times as long (head
occus is mostsimilartotwogeneraalsoconfined to uropod) as wide, flat, 6 times as long as high,
to southern Australia, Juletta and Margueritta. smooth. Head less than halfwidthofbody, ante-
Both are flattened (weakly so in Margueritta), riorly produced as a semi-circular plane, pos-
smooth, possess a ventral rostrum, and have a terolaterally weakly insetinto pereonite 1. Pere-
simple mandibularincisor. They also lackacom- onite 1 longer and narrower than rest. Coxae
plete suture between pleonites 5 and 6, a condi- extending about one-quarter of body width
tion found rarely in Sphaeromatidae. The new beyondbases ofpereopods; adjacentcoxal plates
genus differs from thesetwo in being exception- interconnected by ventral coxal keys. Pleonite 1
ally flattened, in possession of falcate pereopo- indicated only by short slit lateral to ventral key
dal dactyli, and simplicity ofthe molarprocess. near base of pereopod 7. Pleotelson apex exca-
No adult malecharacters areused in this diag- vate, upturned, together with uropod endopods
nosis since only one apparently mature male is forming exit hole.
available inthetype species. Thisspecimen, with Eyes lateral, small. Epistome wider than long,
well developed penes, lacks appendices mas- curving around labrum; labrum weakly divided
Figure 1.Maricoccusbrucei,juvenile,4.4mm,SAMC0O00. a,dorsalview,b,ventralview(leftpereopodsand
pleopod 1 removed), c, lateral view. Scale line= 1mm.
MARICOCCUSBRUCEI, A NEW GENUS AND SPECIES OF SPHAEROMATIDAE 73
1
GARY POORE
174 C. B.
Figure 2. Maricoccus brucei,juvenile, 4.4mm, SAM C5509. a, mouthparts and antennae in situ. Al, antenna
1. MD, mandible (a, rightventral; b, rightincisorand spine row, anterior; c, leftdorsal). MX1,MX2, maxillae
1, 2. L, left labium.
MARICOCCUSBRUCEI, A NEWGENUS AND SPECIES OFSPHAEROMATIDAE 175
Figure3 Maricoccusbrucei,juvenile,4.4mm, SAMC5509.MP,maxilliped(a,right,posterior;b,rightendite,
posterior; c, left endite, anterior). PI, left pereopod 1 (a, lateral; b, propodus and dactylus, mesial; c, unguis,
lateral). P2, leftpereopod 2, lateral.
176 GARY C. B. POORE
Figure 4. Mciricoctus brucei, juvenile, 4.4mm, SAM C5509. P4, left pcrcopod 4, mesial P7 left pereopod 7
lateral.PL1-PL3,leftpleopods 1-3.
Juvenile,4.5mm, NMV .114028. PL4, PL5, left pleopods4,5 (all pleopods tosame relativescale,typieal setae
only shown),
Male, 4.6mm, AM P41376. PL5a, pleopod 5,
MARICOCCUSBRUCE!, A NEWGENUS AND SPECIES OFSPHAEROMATIDAE 77
1
intoproximal and distalparts,completelycover- almostas broadaslong, with 18 distal setae, with
ing mandibular incisors. thickenedrugosedistal margin. Pleopod 2 endo-
Antenna 1 bases separated by ventral rostrum; pod 1 .5 times as long as exopod, with 13 diso-
peduncle article 2 0.8 length of article 1, lateral setae on oblique margin, thickened and
anterodistally produced; article 3 articulating rugose on distal and midmesial margin; exopod
subterminally on 2, about half as long as article ovate, with 19marginal setaeondistal half.Pleo-
2; flagellum shorterthan peduncle, of1 shortand pod 3 rami narrow, acute; endopod longer, with
7 longer articles bearing 0, 0, 2, 2, 1, 1,0 aes- 8 setae; exopod curved with 30 setae. Pleopod 4
thetascs. Antenna peduncle geniculate between endopod longer and more acute than exopod,
articles 4 and 5; article 1 short; article 2 4 times both rami with c. 7 transverse thickened ridges.
as long as first; article 3 half as long as second; Pleopod 5 endopod longer than exopod, with 2
articles 4 and 5 progressively increasing in apical scaled lobes, both rami with c. 5 trans-
length; flagellum of 10 articles bearing minute verse-obliquethickenedridges. Uropodattached
setae. near lateral suture of pleotelson; rami meeting
Mandibles symmetrical; incisors chitinised, posteriortoapex oftelson, length2.5 timesgreat-
brown, oblique-posteriorly directed and over- est width; exopod shorter, ventral, apex round-
lapping, distally rounded; spine row of 12-13 ed-truncate.
flattened bent spines of which the longest lie Female. No ova- or embryo-bearing females
against the incisor; molar process blunt, with observed.
basal seta; palp basal article held in overlabrum;
articles 1 and2subequal; 2 with 6pectinate setae Colour. Deep violet when alive (V. N. Sergeev
on distal half; 3 with 7 pectinate setae. Maxilla pers. comm.); dull white-yellow in alcohol,
1
semi-transparent.
inner lobe with 2 long setulate setae and sim-
1
ple short seta; outer lobe with 11 short strong Size. Up to 4.6mm, mancas ranging from 1.5 to
setae. Maxilla 2 laterally expanded; inner lobe 2.7mm.
with 5 setae of various forms; middle lobe with
2 setae; outer lobe shorter than middle, with 1 Distribution. Shallow coastal waters of South
setae. Maxilliped without defined coxa or epi- Australia, Victoria and Tasmania at depths
pod; endite truncate, with 2 complex clubbed between 12 and 52m, from red algae, bryozoans
setaeon anteriorface nearmesial margin; with 3 and sea grasses.
strong plumose setae on distolateral margin; 4 Etymology. For Niel Bruce in recognition ofhis
narrow fan-shaped spines on posterior face; and contribution to the taxonomy of Australian
1 simple coupling hook mesially. Maxillipedal isopods.
palp 2.5 times as long as endite, article 1 short;
articles 2-4 mesially lobed and setose; article 5 Remarks. Most ofthe specimens, including that
longer than 4, distally setose. illustrated, aresmall and lacktransverseridgeson
Pereopod half length of other pereopods; pleopods4 and5. They are, however, quiteclear
1
merus and carpus with posterodistal setae; propo- on the largest specimen, a male (fig. 4: PL5a).
dus with 4 mesial pectinate setae, dactylus as This specimen has small pairedpeneson thepos-
long as propodus, with short unguis and blunt terior margin of pereonite 7 but has no appen-
accessory unguis. Pereopods 2-7essentially sim- dices masculinae. It is uncertain whether or not
ilar; third slightly shorter than second; fourth to this is a fully adult specimen.
sixth ofsimilarsize; seventh slightly more elon-
Acknowledgements
gate. Pereopod 4 merus with fine posterodistal
spine; carpus with stout flagellate posterodistal I thank Dr Val N. Sergeev, South Australian
spine and plumose anterodistal seta; propodus Fisheries Department, fordonation ofspecimens
slightly curved, dactylarlateral articulating plate and Penny Berents (Australian Museum) and
indicated by finetransversesuture, with fewshort Wolfgang Zeidler (South Australian Museum)
posterior and anterodistal setae; unguis minute, forloanofspecimensfrom theircollections. I am
secondary unguis blunt. especially indebted to Niel Bruce (Queensland
Paired penes on the posterior margin ofpere- Museum) for many useful contributions to dis-
onite 7, longer than wide. cussionofthe systematicposition ofthis animal.
Pleopod overlapping only half pleopod 2, Keith Harrison (London) and Rick Brusca (San
1
endopod shorter than exopod, with 14 setae on Diego) made sensible comment on a very early
distolateral margin; exopod widest distally, version ofthis paper.
178 GARY C. B. POORE
References Australia, with a reappraisal ofthe Sphaeromatidae.
Invertebrate Taxonomy7: 151-171.
Baker,W.H. 1908.Notesonsomespeciesoftheisopodfam- Harrison, K., 1984. Somesphaeromatidisopods(Crustacea)
TilryanSspahcateiroonsmiadnade,PrforcoemedtihnegsSoouftthheARusotyraalliSaonciceotaysto.f from southern and south-western Australia, with
SouthAustralia32: 138-162. description of a new genus and two new species.
Brandt, A., and Wagele, J.-W. 1989. Redescriptions of Records of the Western Australian Museum 11:
CymodocellatubicaudaPfeffer, 1887andExosphaero- 259-286.
magigas(Leach, 1818) (Crustacea, Isopoda, Sphaero- Holdich, D.M., and Harrison, K. 1980. The isopod genus
matidae).AntarcticScience 1: 205-214. DynamenefromAustralianwaters, withdescription of
Bruce, N.L. 1993. Two new generaofmarine isopod crus- anewspeciesfromcoralreefs.MemoirsoftheQueens-
taceans (Flabellifera: Sphaeromatidae) from southern landMuseum20: 163-170.