Ocellate octopuses (Cephalopoda: Octopodidae) of the Great Barrier Reef, Australia: description of two new species and redescription of Octopus polyzenia Gray, 1849

36 Pages·1992·9.5 MB·English

by  Mark D Norman

Memoirs ofthe Museum ofVictoria 53(2): 309-344 (1992)
OCELLATE OCTOPUSES (CEPHALOPODA: OCTOPODIDAE) OF THE GREAT BARRIER
REEF, AUSTRALIA: DESCRIPTION OF TWO NEW SPECIES AND REDESCRIPTION OF
OCTOPUS POLYZENIA GRAY, 1849
By Mark D. Norman
Invertebrate Zoology, Museum ofVictoria, 285 Russell Street. Melbourne, Vic. 3000, Australia
Abstract
Norman, M.D., 1992. Ocellate octopuses (Cephalopoda: Octopodidae)oftheGreat Bar-
rierReef, Australia; descriptionoftwo newspeciesand redescription ofOctopuspolyzenia
Gray, 1849. Memoirs ofthe Museum ofVictoria 53: 309-344.
Fourspeciesofocellateoctopusesarereported fromthewatersoftheGreat BarrierReef,
Australia. Ocellate octopuses exhibit a false eye-spot (or ocellus) on the arm crown below
each eye. Octopuspolyzenia Gray, 1849 is reported as an ocellate species forthe first time
and is redescribed based on examination ofthe type and specimens from tropical waters
across northern Australia. Two new species, O. exannulatus and O. mototi spp. nov. are
describedanddetailsofdistributionandlifehistoryarepresented.ThewidelydistributedO.
cyanea Gray, 1849 is the fourth ocellate species found on the Great Barrier Reef. Octopus
cyanea shows different affinites to the otherthree species and may be ofseparate origin. A
key for ocellate octopuses ofGreat Barrier Reefwaters is provided. Delineation ofGreat
Barrier Reefocellate octopuses from others ofthe tropical Indo-West Pacific is discussed.
Distribution patterns also are examined.
Introduction ern Queensland (Smith, 1884). In examining
these specimens in theBritish Museum (Natural
Since the early 19th century, teuthologists
have been familiar with ocellate octopuses, History), it was discovered that both possess
manv authors discussing them in detail (Brock, ocelli with an iridescent ring and both were
M11c9828C97o;;nBnAearduravgm,h,e1y911,923.199,149911;29aV5;9o,sRso1ba9sn7o3dn;,SoPl1ii9cs2k9Rf;aorSmadisraaeknzid,, dm1aa2.yt3urmIe.mmasMlpLees,cidmBeesMnp:iNtHe1t4h1.e81i4r5s.mm5a.ml1l4.s7Mi8zLe,a(nhdoBlToMhtuyNrpseH-:
1882.2.23.568). An additional 14 specimens
1966). Ocellate octopuses are shallow-water
were found in Australian museum collections
sdpaerckiefsalcsheaeryaec-tseproitssed(obryotcehlelip)reosnenthceeaofrmapcariorwonf (NTM, AMS, WAM, NMV). Octopuspolyzenia
eoyvee.rItnhembaansyesooffthaersmeso2ctaonpdus3e,sotnheebdealrokwoecealclhi wishihcehrelaryesdleasrcgreiebgegdsaasndaocscmualrlsioncceolalasttealswpaetceiress
across northern Australia. Species accounts are
each contain a fine ring of iridescent tissue, presented fortwo new ocellate species, O. exan-
which is expressed as a brilliant metallic blue or nulatus and O. mototi, along with information
gold ring in live animals.
Recent research into the shallow-water octo- ondistribution,lifehistoryand liveanimalattri-
butes.
puses of the Great Barrier Reef, Australia has
uncovered many octopus species (Norman,
Material and methods
1991, 1992a, 1992b), including four ocellate
species: Octopus cyanea Gray, 1849, O. poly- FieldworkontheGreat BarrierReefwascarried
zenia Gray, 1849 and two new species, O. out between May and November in 1989 and
exannulatus and O. mototi spp. nov. 1990. LivespecimensofO. cyaneaand O. mototi
Octopuscyaneaisawidelydistributedtropical wereencountered in the field duringtheday and
Indo-West Pacific species, found in coral reefs. at night on intertidal reef walks, snorkel and
It has previously been reported from Australian SCUBA dives and caught in octopus pots in
watersby Roperand Hochberg(1987, 1988)and deeperwater. Individuals were observed in situ,
Norman (1991). Octopus polyzenia was pre- collected, photographed, narcotised in fresh
viously known only from the type specimen water, and fixed and preserved according to the
from Port Essington, Northern Territory (Gray, techniquesofRoperand Sweeney (1983). These
849)and a small male from Thursday I., north- specimens are now in the Museum of Victoria
1
309
.
MARK NORMAN
310 D.
(NMV). Preserved specimensofall fourocellate per cent of ML; Hectocotylized Arm Sucker
Reef species were found and examined in the Count (HASC): number ofsuckers on hectoco-
collections of the Australian Museum, Sydney tylized arm (see Toll, 1988); Terminal Organ
(AM), Queensland Museum, Brisbane (QMB), Length Index (TOLI): length ofterminal organ
Northern Territory Museum of Arts and Sci- as per cent of ML; Diverticulum Length Index
ences (NTM), Western Australian Museum (DLI): diverticulum length as per cent oflength
(WAM), National Museum ofNatural History. of terminal organ; Spermatophore number
Washington (USNM), Californian Academy of (SpN): number of spermatophores in Need-
Science (CAS), British Museum (Natural His- ham'ssac;Sperm CordWhorls(SpCW): number
tory)(BMNH)and Museum Nationald'Histoire ofwhorls in which sperm cord is coiled; Funnel
Naturelle, Paris (MNHN). Length Index (FLI): funnel length as per cent of
In the description and tables, measurements ML; Free Funnel Index(FFI): length offree fun-
and indices follow Voss (1963) and Roper and nel portion as per cent offunnel length: Funnel
Voss(1983). Terminology has been modified by Organ Index (FOI): length ofouter limb offun-
Hochberg and Mangold (in prep.) for several nel organ as per cent of median limb length;
anatomical structures: "copulatory organ" Funnel Organ Length Index (FOLI): length of
replaces the term "hectocotylus" and "terminal medial limbas percent offunnel length; Ocellus
organ" replacestheterm "penis". The following Diameter Index (OcDI): diameter ofocellus as
ML
additional or slightly modified indices also are a per cent of (specified as referring to
employed: iridescent ring or entire dark web spot).
Stage of Maturity (StM): Immature (I: sex Indices are presented for both sexes com-
indeterminate or reproductive organs minute). bined, except where significant differences were
Submature (S: reproductive organs distinct but found between the sexes(one-way ANOVA, P=
poorly developed) and Mature (M: developed 0.05 level). In these indices, range and mean for
spermatophores or eggs distinct); Head Width each sex are presented. Where ranges signifi-
Index (HWI): head width as a per cent of ML; cantly overlap, standard deviations around the
Head MantleWidth Index (HMWI): head width mean are also presented.
as per cent ofmantle width; Arm Mantle Index Two additional undescribed ocellate species
(AMI):armlengthaspercentofML:Arm Width have been recognised from northern Australian
Index (AW1): maximum arm width at widest waterswest ofCape York. Due tothe scarcityof
point on stoutest arm, as percent ofML; Sucker material and the apparent absence ofthese taxa
Count(SC): total suckercountforthe intactarm from the Great Barrier Reefregion, these forms
with the most suckers; Gill Count(GC): number have not been included in this work.
ofgill lamellaeperdemibranchnot includingthe Table 8 summarises the key differences
terminal lamella; Hectocotylized Arm Mantle between ocellate octopuses ofthe Great Barrier
Index (HAMI): length ofhectocotylized arm as Reef.
Key to ocellate octopuses of the Great Barrier Reef
Ocellus lacks iridescent ring; either simple black spot (figs la, lOe-f) or
black spot surrounded by a fine dark outer ring (figs lb, 2a) 2
Ocellus consistingofdark spot containingnarrow iridescent blue ring in
live animal, visible as white or pink superficial ring over darkocellus in
preserved specimens (figs 1c, 6h, 14g-h) 3
9-11 gill lamellae per demibranch, typically 10; over 400 suckers on
normal intact arms of submature and mature animals; approximately
200 suckers on hectocotylized arm; ocellus comprised ofdark oval spot
boundbyadditionalthin darkring(fig. lb), iridescenttissueabsent;dark
zebrabarson ventral facesofall armson submatureand matureanimals
(fig. 2d); very large species (ML to 160 mm; weight to 6 kg; fig. lh) .
Octopus cyanea Gray, 849
1
7-8gill lamellaeperdemibranch.typically 7; 120-190suckersonnormal
intactarmsofsubmatureand matureanimals; approximately 70suckers
onhectocotylized arm;ocellusplainblackspot lackinganiridescent ring,
oval shaped and clearly defined (figs la, 10e-f); 4 dark broad longitudi-
nal stripeson dorsal body, continuinganteriorlyon todorsal arm crown
.
OCELLATE OCTOPUSES OF THE GREAT BARRIER REEF, AUSTRALIA 311
(figs 7a, lOa-d); moderate size species(MLto 50mm; weightto 75 g; fig.
10 Octopus exannulatus sp. nov.
6-7 gill lamellae perdemibranch, typically 6; 85-135 suckerson normal
intactarmsofsubmatureand matureanimals; approximately 50suckers
on hectocotylized arm; widely spaced dark transverse bars on all arms
separated by approximately 3-4 suckers (figs 3a, 6d, g); pattern offaint
crucifix oflight patches on dorsal body (figs 3a); small species(MLto 38
mm; weight to 20 g; fig. la) Octopuspolyzenia Gray, 1849
9-11 gill lamellae per demibranch, typically 11; 143-176 suckers on
normal intact arms of mature animals; approximately 100 suckers on
hectocotylizedarm;circularclusterofdarkspotsaboveeacheyeforming
"flower" pattern (figs 1 la, 14a); alarm pattern ofdark longitudinal bars
on dorsal body and arm crown over white base (figs 14b, e); well devel-
oped frontal white spot with prominent elongate papilla (figs 14a, 14d);
moderate to large species (ML to 100 mm; weight to 300 g; fig. lg) .
O. mototi sp. nov.
Octopodidae d'Orbigny. 1839 Pacific from Hawaii in the east to the east Afri-
Subfamily Octopodinae d'Orbigny. 839 can coast in the west (fig. 15a).
1 Aspects ofthe life history of O. cyanea were
Octopus cyanea Gray. 1849 treated in Van Heukelem(1983). Morphological
description and observations oflive Australian
Figs lg, 2a-d, 15a specimens were provided in Norman (1991).
OcSteoepuNsomramramnor(a1t9u9s1)Hofyorlef.ull18a8n5n.otOa.tehdorsstyinJoonuybmiyn., Commercial exploitation. There is no commer-
c1i8li9s8,(ROo.bshoenr.dm1a9n2i8)(aHonydleC,all1i9s0t4o)c.lOo.pucsymaangenaocvearl.lagtruas- cTihalefaissshoecriyatfoironO.ofcythainseaspienciAeusstwriatlhiacnorwaaltearnsd.
Taki. 1964 are synonyms. rockyreefsexcludesitfromtrawlfisherieswhich
work moreopen substrates. No small-scale local
Diagnosis. Large robust species with black oval
exploitation hasbeen noted. Elsewherethrough-
ocellus surrounded by pale ring and thin dark outthetropical Indo-West Pacific, thisspeciesis
outer ring. Ring of iridescent tissue within commonly taken in local and subsistence fish-
ocellus absent. Dark bars on ventral surfaces of
all 4 arms oflarger specimens (ML > about 60 eRreieess,(1H9o5y0l;e,Va1n907H;euBkeerlrye,m,1911928;3;SaRsoapkei,r e1t92al9.;,
mm), formingstripes in alternation with base of
1984).
suckers. 3-7 rows ofcream spots on aboral arm
surfaces from web margin to tips, containing Octopus polyzenia Gray, 849
1
small erectile skin ridges. Skin sculptured in
irregular patch and groove system. 3 pro- Figs Id, 3-6. 15b
cnlaromouewnlncl,eadeesppleaecrrigaedllecymiriicbnurlyaaonrucnhpag,tecrthyeapsniicmaolanllysd.o1r90s.-a1lM1oagrrilmel A12-2OA.c3t—.op—uCsoxHpo,oyllJve8-,8e2n1:i8a7868G:7r.8a.—y8,0.S1m8—4i9t:hL,u131a.8n8—d4:PhT3ir4ly,loipnpis,.,411.897f8i95g::s
than 400 suckers on intact normal arms ofsub- 33. —
mature and mature individuals, approximately Octopus granulatus (non Lamarck, 1798).
200 suckers on hectocotylized arm. Terminal Brazier. 1892: 4. —
organ small and fine (TOLI about 20). Sperma- Octopus—rugosus (non Bosc, 1792).— Ortmann,
tophores short, approximately 40% of ML and 1891:669. Robson, 1929:63,65, 73. Fleckerand
produced in large numbers (SpN >300). Eggs Cotton, 1955: 3.
mm
small, ovarian eggs to 2.7 [ELI(ov) to 1.7], Materialexamined. 16preservedspecimensincluding
and produced in very large numbers (EN the extant type (BMNH 1845.5.14.78) examined in
>100 000). Australian museum collections and the British
Museum (Natural History).
Distribution. Octopus cyanea is recorded from Holotype: NT: lcf: 12.3 mm ML, BMNH
tropical waters of northern Australia, from 1845.5.14.78, Port Essington, 11°16'S, 132WE, pre-
Moreton Bay, southern Queensland (27°23'S, sented by the Earl ofDerby.
53°15'E) to Point Cloates, north-west Western Othermaterial: NT: 31mm: 7.4-8.8 mm ML. NTM
AIustralia (22°42'S, 113°39'E). This species is PI393. Port Essington,Coral Bay(1 1°16'S, 132WE),
widclv distributed in the tropical Indo-West 4.5-6 m, Helen Larson, 18 Oct 1981 (poison station.
MARK NORMAN
312 D.
^t&Mtete*.
a
100mm
9
Figure l.OcelliandbodysizesofGreatBarrierReefocellateoctopuses,a-c.Ocellustypes:a,ocellussimpleblack
spot, lacking iridescent ring or outer ring (as in O. exannulatus). b, dark ocellus contained within a light ring,
whichisboundbyanadditionalthinblackring(asinO. cyanea).c,darkocelluscontainingthiniridescentringon
surface ofskin (as in O. polyzenia and O. mototi).
d-g.Comparativebodysizes: d, OctopuspolyzeniaGray, 1849.e, Octopusexannulatuss<p-nov.f,Octopusmototi
sp. nov. g, Octopus cyanea Gray, 1849.
OCELLATE OCTOPUSES OF THE GREAT BARRIER REEF, AUSTRALIA 313
„ rr™ iR4Q a-t I ivecolourpatternsshowingrange in sculpture and
specimen (NMV F57904: 100.0 mm ML mature male).
sgCCio.alnstiHvuaoasnorasdin)n-,dab21oB29te:Jtaaco3nh2m,.,81rO9of8mcf6kmL(rewueMabsbLPhl,oeeidnwNtiu.tTph(M1is2no°fPP2tI1ic'4noS5nr.1aa,l1ss3h_aD0el°anl5rd2wa'gliEotn)re..-r W23p10ee39°ni60t32pla-a'rm,Sila,mrA,fl:1b42Ma8o6tL°f.r1f,3o5s'msAEK,mBaMarEyu.M,CmHLI.b1,2a6R°,4aA4i01Mn'6Ss(8.f,aCob11roG4d6uu1,4tl°1fn47o29oI',7fdE°a,2tCGW9eau'.;rlSp,fH3e9.no:tfF2aao5brCl.oiae8aury-,t,-
so(At2fro0WcrT°hAm2his-9po)'er.Sln1as?g:1o1S,6u1°r33.vR59eo'yEs,m)emm251armMMy.La,ByaI.r,W1ry9Ao7uW2Mtisl(isd3dor6ene3,,d-gN8W„eo8_dr.A)Mb,iMLDl2al9CmW.rpB1Aoia7weyM.nr,7 T111o949w0:8n°93s57v0.('it7Elr)lam,ew,lmCe(Sd1,MI9L°RR1,OV1'NPS",rMJaa1Vwm4n7e°FsS06u10Kr'i1vEr1)eb,2yy,,"<)1C2.l90e6v3me-,l1a9Gn.6d4JBa(atcyrk,aswolon)f.;f
mm, body missingfrom second specimen,
3B2a9v-8(87.0°D29a'mSp,ie1r6°A3r5c'hEi)p,el1a-g2om.,RBoasrermyaWriylsIo.n,,NoWrbAilMl Diagnosis. Small species with black oval ocellus
Crown of Thor1n Survey, 21 May 1972 (dredged on containingan iridescentbluering. Dark, widely-
snaonrdt)h'er1nJ:e2n4d.4omfmHerMmLi,tcWAI.,M(203°0258-'8S8,, M1 1o5n't31e'BE)e,llFo.IEs., sfapcaecsedo,ftraallnsavremrsse,baaprpsraolxoinmgataebloryal3-a4ndsluactkeerrasl
Wells 70 Aug 1986. m between each bar. Light patches surrounding
SHtrMOaliSdt'"ATlIhe*urrts"1;d4.a1ly*mI2.,4m-(910Mm°L3m,5'MSB,LM1'4A28°2M1.32C'.E42)38,.2566778.,3'-B9To.oW2rCrnme-.s rmaainstelde.sk6in-7rigdiglleslfamoerlmlacerucpiefrixdepamtitberrannocnh,dotryspail-
314 MARK D. NORMAN
4mm
2mm
10mm
mmFiamgnutrlMeeL3r.imdOgaceltse;opF(uAWsMSpo=lCyIfzr6eo4nnit1aa7l9G)wr.haiyt,e1s8p4o9t.cao,mpdolresxa,lbv,ifeuwnnoefl3o3r.g3amnmofsMaLmefesmpaelceim(eAn,Mc,C1c6o4pu1l6a8t)o:rvDoMr6gRan=uod,fo^~r>us6.ajl3
OCELLATE OCTOPUSES OF THE GREAT BARRIER REEF, AUSTRALIA 315
5mm
sFailgiuvraery4.gOlacntdosp;usBpMol=yzbeuncicaalGrmaays,s;18C49=.ca,aedicguems;tiCveDtr=acctroofp3d3i.v3ermtmicuMluLm;feCmRal=e(crAoMp;CD1G64=16d8i)g:esAtSivGe=glaanntde;riIo=r
intestine; IS = ink sac; O = oesophagus; PSG = posterior salivary gland; S = stomach.
b-d, beaks ofsame specimen: b, upper beak, lateral view, c, lower beak, lateral view, d, lower beak, ventral
view.
316 MARK D. NORMAN
Figure 5. Octopuspolyzenia Gray, 1849. a, reproductive tract of 26.3 mm ML male (AM C164179): MG =
tmeuscteisl;aTgiOno=ustegrlmainnda;lNoSrg=anN;cVedDha=mv'assSdaecf;erSeGns1,=b,ssppeerrmamtaotpohpohroircegolfasndamIe; SsGpe2ci=msepn:erCmaBto=pcheomriecntglbaonddyII;STR ==
gslpaenrdm; rPeOser=vopirr,oxci,moavlaroyviodfu3c3t..3 mm MLfemale(AM C164168): DO=distaloviduct;O=ovary;OG=oviducal
OCELLATE OCTOPUSES OF THE GREAT BARRIER REEF. AUSTRALIA 317
cally 6. Approximately 115 suckers per arm in Third right arm in males hectocotylized and
mature females (SC$ 103-775-135, n = 9<&), slightly shorter than opposite arm (OAI: 76.9,
slightlyfewerin maturemales(SCrf 85, 86, 108), 77.4; HAMI: 152.1, 155.7, 195.1). Spermato-
approximately 50 suckers on hectocotylized phore groove well developed and wide with fine
arm. Terminal organ short and robust (TOL1 transverse ridges. Spermatophore guide distinct
about 15). Spermatophores short, approxi- with small papillae. Copulatory organ small and
mately one third of ML and produced in low robust (fig. 3c: LLI 4.7, 5.4, 6.8), ligula roughly
numbers (SpN about 10). Eggs large, spawned conical with blunt tip; groove shallow with
capsules to 7.5 mm [ELI(sp) to 22.9] and pro- raised longitudinal midrib. Calamus well devel-
duced in moderately low numbers (EN about oped and large (CLI 40.7, 44.4, 69.2). Approxi-
250). mately 50 suckers on hectocotylized arm
(HASC: 45, 49, 52).
Description. Based on 3 mature males, and 3 Gills with 6-7 lamellae, typically 6, on both
submature and 4 mature females. Counts and inner and outer demibranchs, plus a terminal
indices are in Tables 1 and 2. lamella.
Small robust species (figs Id, 3a), males to at Digestive tract illustrated in figure 4a.
least 26 mm ML. femalesto 37.7 mm ML, TL to Anterior salivary glands moderately large,
at least 130 mm; weight to at least 19 g. Mantle approximately half of buccal mass length. Pos-
ovoid (MWI 50.4-69.0-85.4) with muscular terior salivary glands well developed, slightly
walls. Styletsnotfound. Pallialapertureofmod- larger than buccal mass. Crop diverticulum dis-
eratewidth,approximately halfofmantlewidth. tinct but not greatly developed. Stomach bipar-
Funnel muscular and broad-based (FLI 34.1- tite. Caecum striated, coiled in single whorl.
39.6-51.2)with freeportionusuallygreaterthan Muscular intestine reflexed approximately one-
halffunnel length (FFLI 44.0-65.5-78.1). Fun- third along length from proximal end. Ink sac
nel organ W-shaped with moderate limbs (fig. well developed, embedded in ventral surface of
3b). Outer limbs slightly shorter than median digestive gland below iridescent tissue layer.
limb (FOI 90.2-95.7-100.0). Funnel organ Anal flaps present.
large, approximately 60% of funnel length Upper beak with moderate hood and slightly
(FOLI 48.0-67.7-73.5). hooked rostrum, concave on cutting edge (fig.
Head of moderate width (HWI 41.1-49.5- 4b). Lower beak (figs 4c-d) with blunt rostrum,
63.3), always narrower than mantle (HMWI narrow hood, widely spread wings and slightly
60.0-72.5-89.5). Neck distinct, slightly flared lateral walls. Ventral view of posterior
narrower than head. Eyes large and slightly margin moderately concave. Radula with seven
pronounced. teeth and two marginal plates in each transverse
Arms of moderate length, 2-3 times mantle row (figs 6i-j). Rhachidian tooth typically has 1
length; from limited material arms appear lateral cusp on each side of medial cone (2 in
slightly longer in females (AMIrf 200.8, 209.1, every fourth row). Lateral cusps in symmetrical
252.0;9236.4-267.7-309.4). Armsrobust(AWI seriation. migrating from lateral to medial pos-
13.0-75.2-25.9), roughly circular in cross sec- ition over four transverse rows. First lateral
tion and taper evenly to fine tips. Dorsal arms teeth unicuspidate with cusp towards lateral
shortest, lateral and ventral arms longer and edge; second lateral teeth unicuspidate and
more robust (AF generally 4=3.2.1 or 4.3.2.1). robust; lateral marginal teeth robust, straight
Suckers ofmoderate size, slightly elevated with and moderately short; marginal plates oblong
distinct radial cushions and scalloped rim. and plain.
Mature males can possess 1-3 enlarged suckers Male reproductive tract illustrated in figure
on all arms, beyond margin of webs at level of 5a. Terminal organ in mature males short and
seventhsuckerpair(SDLn0.3, 11.7, 13.5;97.7- robust (TOLI 14.4, 16.3. 16.8) with robust
9.4-12.9). Arm 4 possesses most suckers, diverticulum (DLI 34.2, 56.1, 70.0), genital
(aSppCr9ox1i0m3a-t/e7l5y-113155,snuck=er9s99)p.erslairghmtliynffeewmearleisn arpobeursttu.reMuscuibltaegrimninoauls.glVaansd ednelfaerrgeends asthoprotintanodf
males(SO?85, 86, 108). Websmoderatetodeep attachment to vas deferens. Spermatophoric
(WD1 26.1-57.4-39.1), deepest laterally, dorsal gland I short and robust with recurved coil
web distinctly shorter(WFtypically D.OE.B.A approximately three-quarters along length.
eorxtDe=nEd.iCn.gBl.eAs)s.thWaenbhmaalrfgwianysaplooonrglyvednetvrealloepeddg,e Sropbeursmtatwiotphhorreiflcexgeldatnidp. INIordeilsattiinvcetlyapspheonrtdiaxnadt
junction of spermatophoric glands and Need-
ofarms.
MARK NORMAN
318 D.
1.
„-..•''.-'...... •.
W^'-.
a b c