National Museums National Museum of Canada of Natural Sciences Ottawa 1975 Publications in Biological Oceanography, No. 9 A New Species of Arctic Eelpout, Lycodes sagittarius, from the Beaufort Sea, Alaska, and the Kara Sea, USSR (Pisces: Zoarcidae) Don E. McAllister a Sr reece cet rer 8 AAT ICORNIA if CALIFUNINIA ay if ‘| ACADEMY OF SCIENCES |§ APR 1 2 1976 Publications d'Océanographie biologique, n° 9 Musées nationaux Musée national du Canada des Sciences naturelles A New Species of Arctic Eelpout, Lycodes sagittarius, from the Beaufort Sea, Alaska, and the Kara Sea, USSR (Pisces: Zoarcidae) National Museum of Natural Sciences Publications in Biological Oceanography, No. 9 Published by the National Museums of Canada Staff editor Frances Smith © Crown copyrights reserved National Museum of Natural Sciences National Museums of Canada Ottawa, Canada Fourth quarter 1975 Information Canada Catalogue No. NM95-7/9 P0987654321 Y798765 Printed in Canada ISSN 0068-7995 Musée national des Sciences naturelles Publications d’'Océanographie biologique, n° 9 Publié par les Musées nationaux du Canada © Droits réservés au nom de la Couronne Musée national des Sciences naturelles Musées nationaux du Canada Ottawa, Canada Quatriéme trimestre 1975 Information Canada N° de catalogue NM95-7/9 T0987654321 A798765 Imprimé au Canada A New Species of Arctic Eelpout, Lycodes sagittarius, from the Beaufort Sea, Alaska, and the Kara Sea, USSR (Pisces: Zoarcidae) Don E. McAllister Pe31Iome flaetca OnucaHue HOBOrTO BUA ANVHHOXBOCTON Oenbatoru (Lyco- des sagittarius), oOvTatowen B BOCTOYHONM Yactu mMopA Bodopta y 6beperoBp ApKtTuyeckouw AnACKYU uv B CeBepHOwW yuactTu Kapckoro mopa y Sbeperosp CCCP Ha rnyOuHe 357-600 m. OH OTNNYaeTCA OT APyrux BUAOB NnukOgAOB: 1) NpocTOW OoKOBON nuHuen, 3arHyTON BHYU3 B NepeaHeN YacTu TeNa U NpOMONKatOWeNCA BAONb OOKOB B AaHanbHON OOnacTu; 2) KpaTKOW AHTEAHANbHONM ANUHON, COocTaBna- lowen 38-42% scen anuubli Tena; 3) ANUHHbIMN OploOWHbIMU NNaBHu- KaMu, NPEBbIWAaKMOWMUMUY NpOAONbHYy!HO OPOuTy rna3sa vu cocTaBNnA- lOuUMN 3,7-5,5% BCeN ANUHbI Tena. CNUHHOM nnaBHUk COCTOUT U3 98-107 nyyen, a aHanbHbIN — u3 82-92 nyyen (B KakgOmM NOogACcYeTe BKNtOUaeTCA NONOBUHa NyYYeU XBOCTOBOrO NNaBHuka); 4) roy OHbIMU nnaBHukamu, HacuuTbiBatwouMnumu 16-17 nyyenw. Bprowuna y 3toro BUga YeEPHAA, TeNO TEMHOe, 6E3 NATEH WNUu NONOC, OObINHO NOKDPbI- Batouwwux Teno U aOAOMeH VU AOXOAAWUX MO 3aTbINKa U OCHOBaHNMA BePTUKaNbHbIX NMNABHUKOB. DJTOT BUA OOUTAeT B BORE C HU3KUMU Temnepatypamyu (HudKe O°C) vu nutaeTcA monntocKamMy Uv gApyrumu O6eCcno3sBOHOUHbIMU. Fonotun storo Busa SKCNOHUPyeTCA B OTTaBe B [OCyMapCcTBEHHOM MYy3ee ECTECTBEHHbIX HAaYK, HAXOMAWIECMCA B BegeHuu OtTgaena rocygapCTBeHHbIx my3eeB KaHaapl. NloOasneHb!l Take HEKOTOPbIEe HOBbIe geTanu K ONnuCcaHuto Lycodes squamiventer Jensen. Summary A new species of long-tailed eelpout, Lycodes sagittarius, is described from the western Beaufort Sea, arctic Alaska, and the northern Kara Sea, USSR, in depths of 357—600 m. It differs from other species of Lycodes by the following characteristics: the single lateral line decurved below the midline anteriorly, and midlateral in position behind the level of the anal region; the short preanal length, 38—42% of total length ; the long pelvic fins exceed- ing the longitudinal orbit diameter and comprising 3.7—5.5% of the total length; the 98—107 dorsal and 82—92 anal fin rays (each count including half the caudal fin rays) ; the 16—17 pectoral fin rays; the black peritoneum; the dark body without light markings; and the scales covering the body and abdomen, and extending onto the nape and the bases of the vertical fins. It inhabits tem- peratures of below O°C and feeds on molluscs and other inverte- brates: The holotype is deposited in the National Museum of Natural Sciences, National Museums of Canada, Ottawa. Some new details are added to the description of Lycodes squamiventer Jensen. Résume L’auteur décrit une nouvelle espéce de lycode a longue queue, Lycodes sagittarius, signalée dans la zone ouest de la mer de Beaufort, au large des cétes arctiques de |’Alaska ainsi que dans la partie septentrionale de la mer de Kara, en U.R.S.S., a des pro- fondeurs variant entre 357 et 600 metres. Elle se distingue des autres espéces du genre par une ligne latérale unique, incurvée vers le bas, située sous la ligne médiane dans la partie antérieure du corps et occupant une position médio-latérale derriére la région anale; par la faible longueur de la région préanale (de 38 a 42 p. 100 de la longueur totale) ; par de longues nageoires pelviennes qui dépassent le diamétre longitudinal de l’orbite et mesurent de 3.7 a 5.5 p. 100 de la longueur totale du corps; par le nombre de rayons des nageoires dorsale (de 98 a 107) et anale (de 82 a 92), chacun de ces comptes comprenant la moitié du nombre de rayons de la nageoire caudale; par des nageoires pectorales soutenues par 16 ou 17 rayons, par un péritoine noir, un corps uniformément sombre et des écailles qui couvrent tant l‘'abdomen que le reste du corps de méme que la nuque et la base des nageoires verticales. L’espéce habite les eaux a température négative et se nourrit de mollusques et d’autres invertébrés. L’holotype est conservé au Musée national des Sciences naturelles, Musées nationaux du Canada, Ottawa. L’article ajoute quelques détails nouveaux a la description du Lycodes squamiventer Jensen. Biographical Note Don E. McAllister, Curator of Fishes at the National Museum of Natural Sciences, Ottawa, since 1958, is also a lecturer at the University of Ottawa. He was born in Victoria, B.C., and received his Ph.D. from the University of British Columbia in 1964. His studies have taken him to such places as Newfoundland, Quebec, the Northwest Territories, British Columbia, and Japan. He has published over 70 scientific papers, including studies on arctic fishes, sculpins, smelts, fishes found in archaeological sites, light organs in fishes, the classification of bony fishes, and a popular guide, The Freshwater Sport Fishes of Canada. His professional memberships include the Canadian Society of Wildlife and Fishery Biologists and the American Society of Ichthyologists and Herpetologists. His hobbies include photography, skin diving, cross-country skiing and bonsai. Acknowledgements The author is very grateful to Eugene Ruff, who collected the specimens and made them available for study. Drs. A. P. Andria- shev, Jorgen Nielsen, N. J. Wilimovsky, and Mr. C. G. Gruchy criti- cized the manuscript. Drs. A. P. Andriashev and J@rgen Nielsen lent specimens under their care at the Zoological Institute of the Academy of Sciences of the USSR, Leningrad (ZIL), and the Universitetets Zoologiske Museum, Copenhagen (ZMUC), re- spectively, and Dr. Andriashev also provided X-rays. Alwyne Wheeler, British Museum (Natural History), London (BMNH#H), Dr. Stanley W. Weitzman, Smithsonian Institution, Washington, D.C. (USNM), and Dr. E. J. Crossman, Royal Ontario Museum, Toronto (ROM), issued catalogue numbers at their institutions for the paratypes. Jadwiga Aniskowicz made X-rays of the study material. C. H. Douglas illustrated the holotype. M. F. |. Smith identified two molluscs from stomach contents. The author wishes to extend his gratitude to all these persons. <@ geagie Rg wo BSE < nce S Figure 1 Holotype of Lycodes sagittarius sp. n., NMC74- 282, 278 mm oa’, from Beaufort Sea, Alaska. Drawing by C. H. Douglas. Introduction Although the shelf ichthyofauna of arctic North America has been under investigation for over two centuries, very few collections have been made in depths over 200 m. Consequently, it was not surprising that the study of collections from as deep as 600 m in the western Beaufort Sea should reveal several significant range extensions and a new species of Lycodes. Two specimens of this new species from the Kara Sea, USSR, were ascribed by Andriashev (1954) to Lycodes squamiventer Jensen. But he noted the essential differences in the lateral line of his specimens from L. squamiventer and suggested that his specimens might repre- sent an independent.species. The collection of seven new specimens provides a firm basis for the present description of the new species. The Alaskan collections were made by Eugene Ruff of Oregon State University on board the Western Beaufort Sea Ecological Cruise of the USCGC Glacier in August 1972. Collections were trawled in from 30 to 600 m in the western Beaufort Sea on the North Slope of Alaska between Prudhoe Bay and Barter Island. An otter trawl with a 3.7 m mouth and a 1.3 cm stretched mesh nylon liner were used. Taxonomy FAMILY ZOARCIDAE SUBFAMILY LYCODINAE Genus Lycodes Reinhardt, 1831 Lycodes sagittarius sp. n., Figures 1-3 Lycodes squamiventer (non Jensen), Andriashev, 1954, p. 297, figs. 167, 169 (ex parte: 2 specimens from northern part of Kara Sea at 595 m); Andria- shev, 1973, vol.1 : p. 546 (ex parte : Kara Sea speci- mens). Holotype NMC74-282: 278 mm <’;; from arctic coast of Alaska about 50 miles NNE of Brownlow Point, at.lat.. 70° 51’ SOM song «17 W: in 357 m; 9 August 1972; field no. WBS11 CG17; deposited in the collection of the Ichthyology Section, National Mus- eum of Natural Sciences, National Museums of Canada, Ottawa. Paratypes NMC74-282A: 197 mm @, and BMNH 1974.10.5.1, 212 mm @; from same haul as holotype, ZMUC P761071, 233 mm Q9, NMC74-275, 250 mm 9, and USNM 212282, 253 mm Q ; all from Beaufort Sea, arctic coast of Alaska, about 43 miles north of Kaktovik, at lat. 70° 43’ 6” N, long. 143° 42’ 48’ W; in 464 m; 5 August 1972; station no. WBS3 CG4. ROM 30520, 164 mm oa’; from Beaufort Sea, arctic Alaska, about 52 miles N of Return Islands, at lat. 71° 13’ 12” N, long. 148° 34’ 24” W; in 600 m; 18 August 1972; station no. WEB $20. ZIL 32050, two o specimens; 179 and198 mm; east of Graham Bell Island, Franz Joseph Land, in northern part of St. Ann Trough at lat..$0° 41’ N, long... 1235 V5 im Ooo) mn; 5 October 1948; Litke station no. 194; collected by V. Vagin. Diagnosis Distinguished from other species of Lycodes by the following characteristics: the single lateral line decurved anteriorly and mid- lateral posteriorly; the short preanal length 38-42% of total length; the long pelvic fins, 3.7-5.5% of total length, that exceed the longitudinal orbit diameter; the numerous dorsal fin rays 98-107 and anal fin rays 82-92 : the moderate number of pectoral fin rays 16-17; the black peritoneum; and the dark body without light markings. ‘ZoIMOYsIuUY eEBIMper Aq Ael-X ‘eyse|y ‘eaS Yojneag wo ‘LO WW g/z ‘Z78z -PLOINN “U ‘ds snise32I16es sapooh7 jo adAjojoy € ainbi4 a sss ea ‘"soyine ay} Aq ydeibojou,g "eysejy ‘88S Mojnesg WwoOly ‘0 WW 8/7 ‘Z8Z -PLOINN “U ‘ds snisez2IBes sapooA7 30 adAjojoH Z aunbi4 10 Taxonomy Meristics D+1/2C 98-107; C 4-6+4-6; A+1/2C 82—92: vertebrae 1 9—21 + 84-88 = 104-109; P 16-17; gill rakers 2-3-+10-13=12-15. Description Lateral line on body consisting of pale neuromasts that descend from above gill cover towards the anal origin at an angle of about 30° from horizontal, then rise vertic- ally to midline usually at a level between the anus and the anal fin origin and con- tinue posteriorly down the middle of the side. But in one case the lateral line rises vertically to the midline one orbit diameter in front of the anus, and in another case an orbit diameter behind the anal origin. A short dorsolateral row of neuromasts may be found on either side of the nape. Head moderate, its length including oper- cular membrane comprising 20-22% of total length, its maximum width equalling or exceeding its depth. Longitudinal orbit dia- meter comprising 14-19% of head length and 3—-5% of total length. Snout length comprising 32-36% of head length and 7—8% of total length. Mental crests of mod- erate height, with anterior ends bevelled and not projecting or fusing together. Gill cover tip slightly pointed, upper edge horizontal. Gill opening wide, descending below pec- toral fin to within 1-3 mm of base of pelvic fin. Posterior end of upper jaw ending behind pupil (holotype) or under front third of orbit. Teeth conical, 14—27 on premaxillary, 3-13 on vomer, 7—23 on palatine, 19—42 on mandible (10, 7, 15, and 42 respectively in holotype), number tending to increase with size. Infralabial lobe narrow, not sharply demarcated anteriorly from lip. Body elongate. Scales cover body in- cluding abdomen, extending anteriorly on nape at least to level of operculum, past the bases of the pectoral fins and the tips of the appressed pelvic fins almost to their bases. Twenty to 27 horizontal rows of scales on the body above the origin of the anal fin. Scales extend onto the vertical fins (even in the specimen with a total length of 164 mm), covering one-quarter to two- thirds of their height. Two digitiform pyloric caeca lie behind the stomach. Orange eggs up to 4.5 mm in diameter were found in a specimen collected 5 August 1948. Dorsal and anal fins long, continuous with caudal fin. Predorsal length 25-29% of total length. Posterior edge of pectoral fin diagonal, without emargination, lower rays exserted, length short, comprising 9—12% of total length. Pelvic fins long, length ex- ceeding longitudinal orbit diameter and comprising 3.7—5.5% of total length. Colour of body and fins a dark brown monotone, scales paler, abdomen and side of head below and behind eyes are darker, but the specimen with a total length of 164 mm has a yellowish body, dark gill cover and abdomen. Buccal and branchial cavities dusky, peritoneum black. Biology Specimens were caught at depths of 357, 455, and 600 m in arctic Alaska, probably at negative temperatures. Judging from sedi- ment in the gut, the bottom was a grey mud. The two caught in the Kara Sea, USSR, were caught at 595 m depth-on a brown mud bottom, where the near-bottom tem- perature was —0.91°C, the salinity 34.96%o, and the oxygen saturation 88%. Eggs in the Alaskan specimens were well developed in early August, but testes in the Kara Sea specimens were poorly developed in early October (Andriashev 1954), suggesting late-summer or early-fall spawning. Stom- achs of Alaskan specimens contained anne- lids, bivalves and gastropods (Yo/diella intermedia Sars and Cyclichna cf. occulta Mighels and Adams), and crustaceans. The high number of vomerine teeth (more round-tipped in larger specimens) in this species may be an adaptation to a duro- phagus molluscan diet. The holotype and topotypic paratypes were taken with Ra/a sp., Reinhardtius hippoglossoides, Lycodes seminudus, L. squamiventer, and a liparid. The other Beaufort Sea paratypes were taken with Cottunculus microps(?),Lycodes eudipleurostictus, and L. seminudus. Boreo- gadus saida were also taken in both collec- tions, but were probably taken in midwater during descent or ascent of the otter trawl. The Kara Sea paratypes were collected with a male /riglops nybelini and a male /ce/lus bicornis. Etymology The specific name, sag/ttarius, is taken from the Latin sagittarius, an archer, in reference to the bow it carries in the anterior portion of the lateral line. The specific name is treated as a masculine noun in the nomi- native singular standing in apposition to the generic name. 1 %GC 8 LV %LC 9°0S YLT vcs %6C Lito %8T c vg %8C OLL %LC L°69 %EC he ro) 00 y}Hua} JBESIOPald %LE %EBE %8 TL %9 6°09 L'v9 S& oo v0 L'6 %8E %OV %8 %TL %D 9°69 evs GVL Sle 08 VE %IE %6 %OL %V L’G9 OFOL GOL VSL €'8 %CV VV %6 %TL %G 088 C6 VEL GSC EOL %LL %CV %8 %OL %V D6 L'86 G6L Loc COL %BE %CV %6 %LL %G C86 O'90L Q'LC CLC Lcib %8E %OV %8 %OL PV 6'°S6 O';OOL O'be VVC OF Lik %OV %LV %6 %6 %V Oiaet OT EL LEC L'SZ VOL o U oF a”) er o U o U eee 2 et Ge thes ae D Ss c oS Ss S 2 oy =: a | 5 eo) %L %G %LT %6 cH gL O've ect %8 %E ToLG %OL vrl v9 9'6E BLL %L %E %6 | %O0L fp call ome vLe Z6L %L %Y %0Z %LL aq! QL Sey S77 %L %Y %LZ %6 9'S1 €'6 9'8P ae %L %E %LTC %LL BOL L'8 WAS O'LZ %L %E %OT %OL vLL 6'9 G'6Y 9'GZ %8 %E %CC %OL otc L'8 Z'09 8°97 ao 20 or 20 ao 5s a. a5 $5 eo so oeS @ ae =| Jaquinu udawideds | — OcSOE WOU VC8c-VLOWN OSOCE 11Z LGOL'vZ6L HNWA LLOL9Ld DNWZ GLC-VLOWN C8CCLC INNS! adAjoOJOH c8c-VLOWN Jaquinu enbojejes U}Hus] je}0} Jo }u90 Jad /sesjouuiivd ul “U “ds sni4e22zIGeS sapodAT jo S}usWaINSed|/\ L e19eL 7Z Comparison with Other Species The genus Lycodes may be divided into long- and short-tailed members. Long- tailed Lycodes have the anterior portion of the lateral line ventrally directed, a longer urosome, more dorsal and anal fin rays, more vertebrae, tend to be more completely scaled, more often have black instead of light peri- toneum, and tend to inhabit deeper and cooler waters. With the possible exception of one or two species, the long-tailed Lycodes seem to form a natural group. Their ventrally directed lateral line is probably an advanced condition compared to the wholly mid- lateral state. The black peritoneum of this group may be an adaptation to eating bio- luminescent prey (McAllister 1961); the long tail may be related to the selective value of bearing an increased number of neuromasts in deeper-bottom waters (Mar- shall 1971: 146). The long pelvic fins in Lycodes sagittarius may have achemosensory function, assisting the eelpout in locating food in the light-poor arctic deepwater en- vironment, as suggested by McAllister (in press) for other taxa of arctic fish. Lycodes sagittarius is a long-tailed spe- cies. It differs from all except seven species in the genus by possessing a single lateral line anteriorly decurved, posteriorly mid- lateral. These seven species, which are restricted to the western North Pacific (except for L. palearis, also found in the eastern North Pacific) and to the neigh- bouring Bering and Chukchi seas, may be individually distinguished from the new species as follows. Lycodes palearis has shorter pelvic fins that comprise 1.1—3.1% as compared to 3.7—5.5% of total length, pale instead of black peritoneum, anterior ends of mental ridges projecting instead of bevelled. Lycodes brevipes ochotensis has pelvics shorter instead of longer than the orbit dia- meter, dorsal rays 87 as opposed to 98-107, anal rays 76 as opposed to 82—91, pectoral rays 20 as opposed to 16-17, and perito- neum dark grey instead of black.* Lycodes soldatovi has mental crests projecting an- teriorly; pectoral rays 22-23 instead of 16—17; and pelvic fins about half, instead of more than, the orbit diameter. Lycodes ygreknotatus has pelvic fins only half, as opposed to exceeding, the orbit diameter; dorsal rays 88 as opposed to 98-107; anal rays 77 as opposed to 82-92; pectoral rays 21 as opposed to 16—17; and five Y-shaped white markings as opposed to none. Lycodes microlepidotus has pelvic fins shorter than *“Lycodes brevipes brevipes has pelvic fins less than one-half, instead of exceeding, the orbit diameter; a single ventral lateral line; pectoral rays 19-21 instead of 16—17; and pale instead of black peritoneum. L. 6. diapteroides has a single lateral line descending toward the anus but disappearing under the pectoral fin without a midlateral section, pectoral fins with 19—20 rays instead of 16—17, and pelvic fins less than one half the orbit. Lycodes brevipes ochotensis may well represent a species distinct from the other two subspecies on the basis of the lateral line, low dorsal and anal fin ray counts, and no light bands crossing the dorsal fin. Table 2 Meristic data for Lycodes sagittarius sp. n. 2 2 a e $$ © O00! Spee fe = Ete Gyilim Se: 62 $s Oo She) OE see = oS Catalogue number ieee eet Kae NMC74-282 Holotype 1 99 9 82 USNM 212282 2 TGS 8 91 NMC74-275 1 98 8 83 ZMUC P761071 Ss 107 8 84 BMNH 1974 .10.5.1 Zz 04 8 84 NMC74-282A 4 102 8 90 ROM 30520 1 107 1.2 a2 ZIL 32050 1 101 9 a4 ZIL 32050 2 og S) 87 Left » é 7) ” © c 6 . piechie tek pet et ena 5 - kann ieee. Vee s eee ban ey ae 2 3 23 Sf = 85 of & S&S Se RES 9 Os Oo - Per pee TES Cy ORS ge owl arr TE aig TE ON 1G NODE TINges oMeetty TE? Pag Mg FANGS STEIN Ow obs PPO FOE SA Pa Bah A eS UMS Terre: TR 15 Yr aie ere tre PP iY 7 eakipgNsQIs HG IAGigg a