Paraliparis haploporus, Stein, 2012

Stein, David L., 2012, Snailfishes (Family Liparidae) of the Ross Sea, Antarctica, and Closely Adjacent Waters 3285, Zootaxa 3285, pp. 1-120 : 57-59

Paraliparis haploporus n. sp.

Figs. 39, 40

Holotype. NMNZ P.046423, immature female, TL unknown, 88 mm SL, 71°52.37' S, 174°04.28' E, NW edge of Mawson Bank, R / V Tangaroa, Stn. IPY / CAML TAN 0802 /167, 25 February 2008, 1954– 1990 m. NMNZ P.046423/1, cleared and stained right pectoral girdle.

Diagnosis. Chin pore single, round. Teeth tiny, simple canines in oblique rows forming moderately wide bands in both jaws. V 75, P 22–23. Head short, HL 18% SL, HW 10% SL, 59% HL, eye not large, 16% HL. Radials 3 (2+0+1). Preanal fin length 33%, preanus length 16%, anus-anal fin distance 17% SL. Pectoral fin upper lobe about 93% HL. Body color probably dark brown.

Description. Counts. V 75 (10+65), D 68, A ~63, C na, P 22–23 (16+2–3+4), radials 3 (2+0+1), pc>3, pore formula unknown. Ratios. HL 17.6, HW 10.3, sn 5.3, E 2.8, orbit 5.4, io 6.7, uj 7.6, go 2.2, bd 15.9, preD 22.7, preA 33.0, aAf 17.3, UPL 16.4, LPL 12.5. In % HL: HW 58.7, sn 30.3, E 16.1, orbit 31.0, io 38.1, uj 43.2, go 12.2, bd 90.3, preD 129.0, preA 187.1, aAf 98.1, UPL 92.9, LPL 71.0.

Head short, narrow, and low, its dorsal profile rising at a shallow angle from snout to behind orbit. Snout short, blunt. Nostrils on a horizontal with upper half of pupil. Mouth horizontal, subterminal, oral cleft short, barely reaching anterior margin of orbit. Lower jaw included. Teeth in both jaws simple, tiny canines, in about 15 oblique rows of up to about seven teeth each, forming moderately wide bands nowhere uniserial. A narrow gap present at premaxillary symphysis, a wide one in mandible. Eye about 1/6 HL, not prominent. Gill opening short, completely

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pores chin

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046423

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girdle pectoral

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046423

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Holotype

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haploporus

Paraliparis

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39

FIGURE above pectoral fin base, a little more than 10% HL, not reaching ventrally to uppermost pectoral fin ray. Opercular flap obtusely triangular, opercle crescent-shaped, almost horizontal, its anterior end slightly higher than tip. Pore formula unknown owing to damage and absence of skin; remaining mandibular pores moderately large. Chin pore single, large, round, not in a pit or depression, located ventrally near tip of lower jaw; openings of mandibular sensory canals clearly visible in each side of pore. Remaining pores all of similar size, rims pale and thickened.

Pectoral fin well developed, longest ray of upper lobe reaching to end of abdomen and first anal fin ray. Uppermost ray on horizontal with lower margin of pupil, about four rays higher than tip of suborbital stay. Upper lobe of 16 rays, sharp tipped with dorsal rays longest, reaching to about end of body cavity; notch rays two or three, well developed, lower lobe of four rays. Notch rays not distinct from lower rays of upper lobe. Insertion of lowest ray below mid-cheek and anterior to opercle, lower lobe reaching about 2/3 back on abdominal cavity, its tip below bases of lower rays of upper lobe. Radials 3 (2+0+1), round, lacking notches or fenestrae, poorly calcified and stained. Scapula double headed, distal end stout and broad. Coracoid with exceptionally long, slender helve.

Body laterally compressed, deepest about at mid-abdomen. Dorsal fin insertion between vertebrae 5–6, anal fin insertion between vertebrae 10–11. Dorsal and anal fins deepest behind half body length. Anus about below tip of opercular flap, below bases of most ventral upper lobe rays. Peritoneum visible through abdominal wall. Pyloric caeca at least three, short and fat. Hypural complex fused, slit absent. Caudal fin rays missing. Skin thin, fragile.

Color in life was probably black or blackish; remnants of skin on lower jaw and front of head dark brown. Orobranchial cavity dusky, peritoneum black, stomach and pyloric caeca pale. A thin dark line along ventral midline of abdominal cavity.

Distribution. Known only from the type, collected on the northwestern edge of Mawson Bank, Ross Sea, at 1954–1990 m depth.

Etymology. From the Greek haplos, single, and poros, hole, indicating the single chin pore.

Comparisons. In having a single chin pore, Paraliparis haploporus is similar to P. monoporus and to P. ekaporus (see above). It is distinguished from the former by its shorter preanal fin length (33 vs 42% SL), much narrower head (about 10 vs 14–17% SL) and interorbital distance (38 vs 55% HL), and its smaller eye (16 vs about 22% HL). It differs clearly from the latter in its banded teeth (vs posteriorly uniserial), having three (vs four) radials, more dorsal fin rays (68 vs 60), more vertebrae (75 vs 67), smaller eye size (16 vs 24% HL), head width (10 vs 17% SL), shorter predorsal and preanal fin lengths (23 and 33 vs 32 and 46% SL), and shorter anus to anal fin distance (17 vs 31% SL).