Indian Ocean grenadiers of the subgenus Coryphaenoides, genus Coryphaenoides (Macrouridae, Gadiformes, Pisces)

30 Pages·1995·13.2 MB·

by  Yu N Shcherbachev

PROCEEDINGS
OF THE
CALIFORNIA ACADEMY OF SCIENCES
Vol. 48, No. 14, pp. 285-314, 8 figs., 3 tables. March 3, 1995
INDIAN OCEAN GRENADIERS OF THE SUBGENUS
CORYPHAENOIDES, GENUS CORYPHAENOIDES
(MACROURIDAE, GADIFORMES, PISCES)
By
Yuri N. Shcherbachev
P.P.ShirshovInstituteofOceanology,AcademyofSciences,
23KrasikovaStreet,Moscow117218, Russia
and
Tomio Iwamoto
CaliforniaAcademyofSciences, Golden GatePark,
SanFrancisco, California94118
Abstract: Thesubgenus Coryphaenoidesofthe largemacrouridgenus CoryphaenoidesGunnerus, 1765, is
representedintheIndianOceanbyatleastninespecies:C.asprellus(SmithandRadcliffe,1912);C.castaneus
n.sp.;C.hextii(Alcock,1890);C.hoskyni(Alcock,1890);C.macrolophus(Alcock,1889);C.rudis(Gunther,
1878);C.sibogaeWeberanddeBeaufort,1929;C.woodmasoni(Alcock,1890);andanunnamedlong-barbeled
species. C. castaneus is described from four specimens taken on the Ninety East Ridge; it is
mostsimilarto C. longicirrhusGilbert, 1905 ofthe mid-Pacific butdiffers in havinga naked undersideof
snoutandlargerorbits.C.asprellus,previouslyknownonlyfromtheholotypetakeninIndonesianwaters,is
nowrecordedfromfivespecimens taken in the IndianOcean. C. aequatoris(Smithand Radcliffe, 1912)is
questionablysynonymizedwith C.asprellus.Anundescribed,widelydistributedspecies,notableinhavinga
longbarbel,relativelywell-developedoutergillrakers,alongupperjaw,andlowbluntsnoutisleftunnamed.
ThespeciesissomewhatintermediateinitscharacterswithsubgeneraCoryphaenoidesandChalinura.Three
speciesofperipheralwatersareredescribedafterevaluationoftheirstatusfromexaminationoftypespecimens:
C. microps(Smithand Radcliffe, 1912); C. semiscaberGilbertand Hubbs, 1920;and C. tydemani(Weber,
1913).Theymayeventuallybefoundinthearea.AprovisionalkeytoallIndianOceanspeciesofthegenus
isprovided.
ReceivedMay2, 1994.AcceptedOctober 13, 1994.
Introduction rations beginning in the mid-1960s and extend-
ing through the 1980s. The Indian Ocean was
TheIndianOceanhasadiverseandinteresting widely sampled by Soviet trawlers, and at con-
deep-seafish faunathatwas firstbroughttolight tinental slope depths, grenadiers formed one of
atthe turn ofthecentury through expeditionsof thechiefcomponentsofthefauna.Theextensive
the Challenger, Investigator, and Valdivia. Few collections ofdeep-sea fishes from these Soviet
subsequentexpeditionsinvestigatedthedeep-sea expeditionsare largelydepositedattheShirshov
fauna until the former Soviet Union expanded InstituteofOceanology(IOAN)andtheZoolog-
its world-wide fishery and oceanographicexplo- ical Museum of Moscow State University
[285]
58
286 PROCEEDINGSOFTHECALIFORNIAACADEMYOFSCIENCES,Vol. 48,No. 14
(ZMMGU), both in Moscow, and at the Zoo- from which specimens were examined include:
logical Institute (ZIN) in St. Petersburg. AMS, BMNH, CAS, ISH, RUSI, SAM, USNM,
ThisisthefourthofaseriesofpapersonIndian ZMA, ZMUC, and ZSI.
Ocean grenadiers that we and Yuri I. Sazonov
(ZMMGU) have collaborated on. We treated Key to Indian Ocean Species ofthe Genus
speciesofthe subgenus Chalinura ofgenus Cor- Coryphaenoides
yphaenoides in a previous paper (Iwamoto and The following key is provided as a guide to
Shcherbachev 1991), Kuronezumia in a second
identifying all species ofthe genus found in In-
paper (Shcherbachev, Sazonov, and Iwamoto
dian Ocean waters. Three Indonesian and Phil-
1992),andKumbainourmostrecentpaper(Iwa- ippine species are also included as they may
moto and Sazonov 1994). The present paper
eventually be found in the area, but four others
treats nine species of the subgenus Coryphae-
are not, owingto thelackofadequate study ma-
noides (as defined by Iwamoto and Stein, 1974)
terialtocharacterizethespecies.(Anasteriskfol-
known from the Indian OceanandadjoiningIn-
donesianand Philippineseas. Threespeciesthat lowinga species name indicates that it has been
keyed out twice.)
appear to form a natural group (see Gilbert and
Hubbs 1920:413-414)with C. macrolophus(Al- 1a. Upperjawextendstoposteriorxhoforbit
cock, 1889)are included even though they have or beyond 2
yettoberecordedfromtheIndianOceanproper: 1b. Upperjawfalls shortofreachingto pos-
C. microps (Smith and Radcliffe, 1912) and C. terior Vi oforbit 1
semiscaber Gilbert and Hubbs, 1920, from the 2a. V. 7 3
northern Philippines; and C. tydemani (Weber, 2b. V. 8-13 5
1913),knownfromcapturesintheArafura,Bali, 3a. Innergill rakerson firstarch 16-19 total
Ceram, and Flores seas and offCelebes. Proper 4
characterization ofthese three species has been 3b. Innergill rakers on first arch 10 hextii*
difficult,andwehopethatourfreshviewofthem 4a. Chinbarbel rudimentary; agreatlyelon-
will help clarify identification problems and in- gated ray in pectoral and pelvic fins
dicate the areas needing more study and more subserrulatus
specimens. 4b. Chinbarbelwelldeveloped;pectoraland
The genus Coryphaenoides poses some ofthe pelvicfinswithoutgreatlyelongatedrays
mostdifficult taxonomic problems in the family serrulatus
foranumberofreasons,including:(1)specimens 5a. Barbel rudimentary 6
often attain large size with consequent ontoge- 5b. Barbel well developed, short to long 8
neticchanges;(2)samplesaresmallbecausethey 6a. Innergillrakersonfirstarch 16-19total;
are, for the most part, deeper living than most V. 8 (rarely 9) mcmillani
other genera; (3) their distributions are often 6b. Innergillrakerson firstarch 8-13; V. 9-
broad, resulting in difficulty in assessing the ex- 11 _ 7
tent ofvariation; and (4) the species often lack 7a. Inner gill rakers on first arch 8-10; in-
good externally visible apomorphies. terorbital width 31-33% ofHL
filicauda*
Methods and Materials 7b. Innergill rakers on first arch 1 1-13; in-
terorbital width 35-42% HL carapinus*
Methods fortaking measurementsandcounts 8a. V. 8 (rarely 9); barbel notably long, 21-
followprocedureselaboratedin Iwamoto(1970) 34% HL; a pronounced heightening of
and Iwamoto and Sazonov (1988). Institutional napeprofilebeginningsomewhatbehind
abbreviations follow Leviton et al. (1985) and mid-lengthofhead,producingastrongly
Leviton and Gibbs (1988). Most of the previ- humpbacked appearance
ously unreported material for this study were sp. 1 [longbeard grenadier]
collectedbyformerSovietUnionvesselsandare 8b. V. 9-13 (rarely 8); barbel short to long,
depositedin Moscowat theZoological Museum 4-26% HL; humpback beginning over
ofMoscow State University (ZMMGU) and the orbits or essentially lacking 9
P.P. Shirshov Institute ofOceanology, Russian 9a. Underside ofsnout naked 1
AcademyofSciences(IOAN). Otherinstitutions 9b. Underside ofsnout completely scaled .... 1
231
SHCHERBACHEVANDIWAMOTO:GRENADIERSUBGENUSCORYPHAENOIDES 287
1Oa. Innergillrakerson firstarch 14-16;bar- about 2 or more ofHL; firstdorsal with
bel long, 23-26% HL; snout bluntly ablackishdistaltip;athinnakedventral
pointed with subvertical ventral profile edge along snout and suborbital region
murrayi 21
1Ob. Innergillrakersonfirstarch8—14;barbel 20b. Elongated spinous ray offirst dorsal fin
short to moderately long, 4-23% HL; 1.2-1.5ofHL;firstdorsallackingablack
snout distinctly pointed 1 tip; snout and suborbital completely
11a. Scales all coarsely spinulated, relatively scaled semiscaber
adherent, especially on head 1 21a. Postorbital length 49-56% HL; orbit-
1lb. Scales thin, weakly or not at all spinu- preopercle distance 44-46% HL microps
lated and highly deciduous 14 21b. Postorbital length 45^9% HL; orbit-
12a. Mandibularteeth in 1 row; underside of preopercle distance 38^41% HL
head almost wholly naked 1 tydemani
12b. Mandibular teeth in narrow band; un- 22a. Underside ofsnout naked; V. 10; snout
dersideofhead almost all scaled, except 27-28%HL; upperjaw38^12%;teethin
for a median swath on snout castaneus lowerjaw in 1 or 2 irregular series lat-
13a. Premaxillaryteethin 1 or2distinctrows; erally castaneus*
outer teeth enlarged, stout, bluntly 22b. Undersideofsnoutcompletelyscaled;V.
pointed armatus 7-10; snout 28-32% HL; upperjaw 27-
13b. Premaxillary teeth in narrow band 3 or 39%HL; teeth in lowerjawin narrowto
4 rows wide; all teeth rathernarrowand broadbands,usually3ormoreteethwide
sharply pointed ferrieri laterally 23
14a. Inner gill rakers on first arch 8-10; in- 23a. V. 7; upperjaw about 39% HL; postor-
terorbital width 31-33% ofHL bital length 53%; internasal 17%; barbel
filicauda* 16% hextii*
14b. Innergill rakers on first arch 11-13; in- 23b. V. 8-10; upper jaw 27-38% HL; post-
terorbital width 35-42% HL carapinus* orbital length 45-53%; internasal 21-
15a. Inner gill rakers on first arch 1 1-16 16 31%; barbel 3-20% 24
15b. Innergill rakers on first arch 8-10 17 24a. Barbel 10-20%HL;V.9-10;preoral 13-
16a. Spikelike processes on preopercle; pos- 15% HL asprellus
terior nostril about 9% HL; interorbital 24b. Barbel 3-9% HL; V. 8-9; preoral 13-
width 29-31% HL grahami 21% HL 25
16b. No spikelike processes on preopercle; 25a. Teeth in lowerjaw in broad band, band
posterior nostril 3-6% HL; interorbital fallsshortofendofrictus;upperjaw27-
width 23-30% HL striatums 30% HL; scale rows below midbase of
17a. Snoutdistinctlyconicalinlateralprofile, ID. 3.5-4.5 hoskyni
protruding beyond mouth; mandibular 25b. Teeth in lowerjaw in narrowband, 3 or
teeth in narrow band about 3 or 4 teeth 4 teeth wide laterally, extends to or be-
wide laterally; upperjaw 33-38% HL yond end of rictus; upper jaw 31-38%
asprellus* HL; scale rows below midbase of ID.
17b. Snout blunt, barely protruding beyond 4.5-6.0 woodmasoni
mouth;mandibularteethin 1-3irregular
rows laterally; upper jaws 39-44% HL
rudis Descriptions
18a. Second spinous ray of first dorsal fin Genus Coryphaenoides Gunnerus, 1765
elongated, 1.2 or more ofHL 19
18b. No greatly elongated ray in first dorsal, Thegenusasusedherefollowsdefinitionsgiv-
height about equal to or less than HL 22 en by Iwamoto and Stein (1974) and Iwamoto
.
19a. Preopercle produced posteroventrally and Sazonov (1988).
formingan acutely angulated corner
_ macrolophus Coryphaenoides asprellus (Smith and Radcliffe,
19b. Preopercle margin broadly rounded 20 1912)
20a. Elongated spinous ray offirst dorsal fin (Fig. l)
288 PROCEEDINGSOFTHECALIFORNIAACADEMYOFSCIENCES, Vol.48, No. 14
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SHCHERBACHEVANDIWAMOTO:GRENADIERSUBGENUSCORYPHAENOIDES 289
Table 1. SelectedmeasurementsofCoryphaenoidesasprellus(holotype),C.aequatoris(holotype),andC.hoskynii(holotype
and6 specimens).Asterisk(*)denotesholotype.
290 PROCEEDINGSOFTHECALIFORNIAACADEMYOFSCIENCES,Vol. 48, No. 14
occipital region, their blackish color contrasting smallgasgland.The90-mmHLmalefromMas-
with light to medium brown ground color. carene Ridge had 8 long, slender caeca and rel-
Gill membranes broadly attached to isthmus atively small gonads.
with no free posterior fold; gill openings extend Color in Exmouth Plateau specimens and fe-
forward close to point below juncture of pre- malefromNinetyEastRidgelightbrownoverall;
opercle and dentary. Outergill slit short, greatly malefromlatterareadarkbrown. Finsallblack-
restricted;rakersalongoutersideoffirstarchfew ish, except outer pelvic ray paler. Barbel light
and rudimentary, other rakers tubercular. brown.Oralcavitygray,palertowardsperiphery,
Mostofbodyandheaduniformlycoveredwith darker on tongue; gill cavity black. Branchios-
moderately large, finely and densely spinulated tegal membranes black; gular membrane dark
scales. Scale size highly variable on head; those grayish brown.
on snoutandonventral surfacesgenerallymuch Distribution.—Indonesia; northwestern coast
smaller; scales alongsuborbital, supranasal, and ofAustralia;andIndianOceanoverSayadeMal-
supraorbital slightly thickened and more adher- ha and Ninety East ridges, in 1,500-2,290 m.
ent;medianandlateralanglesofsnoutwithsmall, Size.—To at least 52 cm TL.
inconspicuous, scutelikescales. Entireunderside Remarks and Comparisons.—The holotype
of head scaled; interopercle naked, as are gill of C. asprellus is badly deteriorated, with the
membranes, lips, and nasal fossa. Spinules on headhavingcomeapartfromtherestofthebody.
scales below interspace ofdorsal fins extremely Nonetheless,mostoftheimportantheadfeatures
fine, short, spikelike, and in densely packed, ir- remain for comparison with our material. The
regularly convergent rows. More ventrally and barbelintheholotypemayhavebeenlongerthan
forward on trunk, scales have spinule arrange- the 10% of HL measured, and in closer agree-
ment less well defined, and some spinules flat- mentwiththe 13-20%wemeasuredinourfresh-
tened, approaching lanceolate shape. In 497+ ermaterial. Theoriginal figure suggeststhatpart
mm
male specimen from Ninety East Ridge, ofthebelly,includingthepelvicfins,wasalready
squamation differs slightly; spinules appear gonewhentheillustrationwasrendered.Wewere
coarser, rows better defined and fewer, and me- unable to locate a pelvic fin in the specimenjar,
dian row slightly, but noticeably enlarged. butin theoriginaldescriptionthecountwasgiv-
Premaxillarydentitionconsistsofabroadband en as questionably eight. That count is low for
of small teeth flanked along outer edge with a our material (9 or 10) and raises some doubt as
row of slightly enlarged, sharp conical teeth. towhetherwehavecorrectlyidentifiedourspec-
Mandibularteethallsmall,inaratheruniformly imensasC.asprellus.Otherfeatures,ontheother
narrow band (3^4 teeth wide; slightly wider at hand, like the jaw size, dentition, squamation,
symphysis). barbellength,andgeneralphysiognomy,support
Fins well developed except second dorsal ru- our identification.
dimentary throughout. Long spinous ray offirst The holotype ofMacrourus aequatoris, which
dorsal fin finelyandsparselytoothed, thegreatly weheretreatasajuniorsynonymofC. asprellus,
reclined spikes not overlapping, the ray distally issubstantiallysmallerthanotherspecimens,and
terminating in a hair-fine tip. Outer pelvic ray measurement differences may in part be attrib-
thickened and elongate (probably more so in utabletosize.Thus,thepreorallength(16%HL),
malesthaninfemales)andextendinginonespec- orbit diameter (26%), suborbital width (16%),
imen (102 mm HL from Ninety East Ridge) to and outer pelvic ray (88%) were slightly longer,
1 1thanalray. Pectoraloriginslightlyinadvance and the lengths ofpostorbital (46%), orbit-pre-
ofpelvicorigin,firstdorsaloriginslightlybehind opercle (45%), upper jaw (31%), and preanal
that. Interspace between dorsals short, less than (146%)wereslightlyshorter. Meristiccharacters,
length base offirst dorsal; anal origin below in- however, were in complete agreement.
terspace. The large female from the Ninety East Ridge
Pyloric caeca in 1 10 mm HL male from Ex- showed some differences from the four male
mouth Plateau about 10, relatively short and specimens studied in width of internasal (21%
slender, length oflongestcaecum aboutequal to HL cf. 23-27%), interorbital (22% cf. 27-30%),
orbit diameter. Gonads moderately developed. orbit diameter (24% cf. 21-23%), postorbital
Swim bladder large, with a thick spongy layer length (50% cf. 52-53%), and length posterior
and 4 very slender retia, each terminating in a nostril(3%cf.6-8%).Thelateral-linescalecount
SHCHERBACHEVANDIWAMOTO:GRENADIERSUBGENUSCORYPHAENOIDES 291
overadistanceequaltopredorsallengthwasalso the primary distinguishing character, it being
higher(39 cf. 30-37). In addition, the outerpel- much largerin C. asprellus(usually 13-20% HL
vic fin ray, though missing its tip on both fins, cf.3-9%).Thepyloriccaecacountwassomewhat
appearedshorterandthinnerinthefemale,com- lower (8-10) than in C. woodmasoni (10-14).
paredwiththoseofthemales. Wepresumethese Coryphaenoides asper Gunther, 1877, known
differences to be sexual, as the female was in only from the holotype taken offJapan, is dis-
every other way so similar to the males, es- tinguishablefromC asprellusbyitsbluntersnout
pecially the Exmouth Plateau specimens, that profile, and coarser scale spinulation (spinules
there is no reason to doubt their conspecificity. rather long, hindmost extending well beyond
The male from Ninety East Ridge was trou- posterior edge of scale, dispersed in about five
blinginthatithadadifferentoverallappearance. divergent rows).
Thesnout appeared somewhat blunter, the head
contourssmoother; squamationcoarser,thespi-
nule rows fewer, and with a distinct, enlarged Coryphaenoides castaneus new species
median row; the underside ofhead had smaller, (Fig. 2)
more adherent scales; teeth in the mandible ap- No literature applies to this species, as far as
peared to be in a wider band; and the overall we could determine.
color was darker. In all these characters except Diagnosis.—V. 10,outerrayelongated,about
the snout shape and mandibular teeth, the dark 61-123% HL, extendingwell posteriorto A. or-
male from the Mascarene Ridge was similar. igintobetween6thand 16thray;abroadmedian
Nonetheless, all counts and measurements for nakedareaon undersideofsnout; upperjaw39-
bothspecimensagreedwiththeothers(excluding 42% HL, maxilla extends to below mid-orbit or
sexually dimorphic female characters). With so beyond; greatest orbit diameter 21-23% HL,
little material available, we do not speculate on slightlylessthaninterorbitalwidth(24-27%HL);
these variants. barbel 16-23% HL; premaxillary teeth band 5-
Coryphaenoides hextii appears to be closely 6 teeth wide, with a distinctly enlarged outerse-
related, butapelvicfin raycountofseven iswell ries; mandibularteeth in a narrow band that ta-
below the 9 or 10 ofour specBiMmeNnsH, and there persto 1 row;spinulesonbodyscalesinirregular,
were 13 pyloric caeca in a specimen slightlyconvergent rows, spinuletipsextendbe-
(1892.6.17.4) examined. Also, the snout was yond posterior scale margins.
shorter (25%) and internasal width narrower
(18%). Neitherthe holotype norany other spec- TypeSpecimens.-HOLOTYPE:CAS71486(female,95HL,
imen ofC. hextii was found in the ZSI, but the 420TL);Ninety-DegreeEastRidge,14°42.4'S,86°49.4'E;1760
one BMNH specimen we examined was proba- m; Prof. Mesiatzevcr. 7, tr. 12; 19.111.1979. PARATYPES:
bly sent there by Alcock. (We also examined a ZMMGU P.19259 (155 mm HL, 690+ mm TL); 1451'S,
133-mmjuvenile from Vityaz'cruise 17 station Z86M°4M9'GE;U1P7.61092m6;0P(r1o5f.9HMeLs,ia7t4z0e+v cTrL.);7,star.me11d;at1a9.a1s11fo.r19h7o9-.
2832.) lotype.
Coryphaenoides asprellus is similar in many Three specimens of Coryphaenoides longicirrhus Gilbert,
respectsto C. castaneusbutcanbedistinguished 1905, wereexaminedforcomparison: BPBM 3429(198 HL,
by its completely scaled underside ofsnout (cf. 4ab5o7ut(138600HLT,L);65H0onTLo)l;ul1u7°F5i4s.h5'MNa,rk1e7t4;°1410..91'1W.,19H2e7.ssSGIuOyo6t8;-
naked medially in C. castaneus), broader man- 2.IX.1968. SIO 68-460 (116 HL, 502+ TL); 18°32.0'N,
dibulardentition(aboutfourteethwidelaterally 178°13.4'W, HamiltonGuyot;4.IX.1968.
cf.aboutonerow),anditsshorterupperjaw(33-
38%HLcf. 39-41%). Counts and Measurements (see also Table
Coryphaenoides hoskynii is readily differenti- 3 and Diagnosis).-11,10-11; IP. i18420; total
ated from C asprellus in having a greater inter- GR-I (outer/inner) 3-4/ 9, total GR-II 7-8 / 8-
nasalwidth(28-30%HL), largerorbit(24-30%), 10;scalesbelow ID. 5.5-7.5,belowmidbase ID.
shorter postorbital length (45-46%), shorter or- 4.5-6, below 2D. 7-8, lat.line 34-39.
bit-preoperclelength(45-47%),shorterupperjaw Totallength 412-740+ mm; HL95-159. The
(21-30%), and shorter barbel (about 5-7%). followinginpercentHL:postrostral75-76;snout
Weexaminednumerous specimens, including 27-28; preoral 12-14; internasal 22-24; post,
the holotype, ofC. woodmasoniforcomparison nostril 5-6; suborbital 13-14; postorbital 54-56;
with C. asprellus. Thesizeofthechinbarbelwas orbit-preop. 51-53;gillslit6-8;pre-A. 163-164;
292 PROCEEDINGSOFTHECALIFORNIAACADEMYOFSCIENCES, Vol. 48, No. 14
5 •*
£ 3
SHCHERBACHEVANDIWAMOTO:GRENADIERSUBGENUSCORYPHAENOIDES 293
Table2. MeasurementsandcountsofspecimensofCotyphaenoidesmicrops, C. tydemani, and C. semiscaber.
294 PROCEEDINGSOFTHECALIFORNIAACADEMYOFSCIENCES, Vol. 48, No. 14
suborbital region, interopercle, anteriormost tip rhus, differing only in the presence ofa naked
of mandibular rami, and usual places like gill areaunderthesnout, acoarsersquamation,with
membranes, lips, nostril region, and fins. Scales spinulesonbodyscalesoverlappingtheposterior
alongridgesofheadnotespeciallylargeorthick- margin, and having a slightly narrower interor-
ened into coarsely spined scutes, although those bital(24-27%HLvs.28-30%inC. longicirrhus).
presentmoreadherentthanadjacentscales. Body Additionally, the new species appears to have a
scales moderately large, scale-pocket margins slightlysmallerorbitthatgoes0.75-0.90intothe
darkly outlined, spinules sharp and more orless interorbital width, compared with about 0.63-
conical, in irregularly convergent rows to irreg- 0.78 in C. longicirrhus. These proportional dif-
mm
ular quincunx pattern. In 420+ specimen, ferencesshouldbesubstantiatedwithmorespec-
spinulesinabout 12ormorerowsinlargestscales; imensrepresentingabroadersizerange.Thenew
middle row consisting of 5 or 6 spinules, with species isalsocloselysimilarto C. aspreilus, but
posteriormost spinule slightly enlarged and isdistinguishablemainlybythedentitionon the
broadly overlapping posterior edge ofscale. lowerjaw (narrowband becominguniserial pos-
Premaxillary teeth in a tapered band 5 or 6 teriorly, vs. in a broad band in C. aspreilus), by
teethwideatwidestpart;anenlargedouterseries the completely scaled underside of head in C.
ofconical, slightly recurved, evenly but rather aspreilus,theshapeofthesuborbitalregion(gently
widelyspacedteeth. Lowerjawteethinanarrow convex, almost flat in C. aspreilus, angularin C.
band that tapers to 1 row posteriorly. castaneus),andthesquamation(spinulesofbody
Relativefinpositionssomewhatdifficulttode- scales somewhat lanceolate in C. aspreilus, con-
termine because ofdorsal flexure in all 3 speci- trastedwithdistinctlyspikelikeandconicalin C.
mens, but pectoral apparently farthest forward, castaneus).ThenapeofC. castaneusisalsohigh-
followedbypelvicand firstdorsal. Originofsec- er, with a humpbacked appearance. Color ofC.
ond dorsal close behind first dorsal, about on aspreilusissomewhatpaler,mediumbrownover
same verticalasanal. Secondspinousrayoffirst most ofbody, dark brown to swarthy on head
dorsalratherthin,lengthslightlymorethanpost- and over abdomen. Coryphaenoides castaneus
rostral length ofhead, ending in a hair-fine fil- can be distinguished from C. woodmasoniby its
amentous tip; weak teeth along leading edge larger barbel, higher pelvic fin ray count, and
widely spaced and non-overlapping, becoming generally longer outer pelvic ray.
obsolete in 2 largest specimens.
Pyloriccaecaoffemale holotypeslender, sim-
ple, about 20 mm at the longest. Swim bladder Coryphaenoides hextii(Alcock, 1890)
inthisspecimenlarge, withatough whitetunica Macrurus HextiiAlcock, 1890: 299-300 (one specimen, ho-
externa and a spongy internal layer; 4 slender lotype,female,"22inches"[ca.56cm];Investigatorst. 104;
retia folded once over themselves, each termi- 1,000 fathoms [1,829 m]). Alcock 1892: 351, 353 (female,
natinginasmallglobulargasgland.Thestomach "onmesa)r.lyAl2c3ociknc1h8e9s4l:onpig.,"XIIIn,vefsitg.ig3a.torst. 122,865-880fath-
contained a single, shrimp-like crustacean. —
Overall ground color dark chocolate brown; Diagnosis. V. 7; underside of head com-
fins all blackish; oral, branchial, and peritoneal pletely scaled; upperjaw 34-39% HL; maxillary
lalilnibnlgasc,kainshdobrradnacrhkiogsrtaye.gaLlipasndblgauclka.rNmaekmebdraarneeass etoxtbeenldsowtombiedldolweptohsitredrioofrolhrbtiot;'/»baorfboerlbit1,6-ri2ct1u%s
on parts ofhead, under snout, and on mandible HL; pyloric caeca 12-15; premaxillary teeth in
with a violet hue. Barbel in smallest specimen broad band with outer enlarged series, mandib-
dark brown basally, but distal lh or so whitish; ular teeth in narrow band about 3 teeth wide,
in larger two specimens, barbel uniformly me- inner series slightly larger than outer two.
diDuimstbrriobwunt.ion.—Known only from the holo- 18M92a.t6e.r1i7a.4lE(x1a2m0inemdm.-NHLE)O;TYLaPcEca(dhievreedeSesai;gnat1e2d°)05B'M55N"NH,
typeandtwoparatypestaken ontheNinetyEast 71°33'30"E; 865-880 fm [1,581-1,609 m]; "Investigator" st.
Ridge in the Indian Ocean in 1,760 m. 122.ZMMGUuncat.(22.6HL,133TL);offSomalia; 12°43'N,
Size.—To more than 740 mm TL. 52°44'E;2,380-2,300m;VITYAZ'cr. 17,st.2832; 16.1.1989.
Etymology.—From the Greek, castaneus, of Counts and Measurements (BMNH speci-
chesnut color. men first, followed by ZMMGU).-1D. 11,9,
Remarks and Comparisons.—Coryphae- 11,10; lP.-/il9, 121/121; GR-I (outer/inner)-/
noides castaneus is most similar to C. longicir- 1+1+8,ca.6/2+8;GR-II(outer/inner) 1+1+7/