Paraliparis pseudokreffti, Stein, David L., 2012

Stein, David L., 2012, A Review of the Snailfishes (Liparidae, Scorpaeniformes) of New Zealand, Including Descriptions of a New Genus and Sixteen New Species, Zootaxa 3588, pp. 1-54 : 29-31

Paraliparis pseudokreffti n. sp.

Fig. 23

Holotype. NMNZ P.038023, female, 128 mm SL, 136 mm TL, 46°38.80' S, 178°30.03' E, Bounty Trough, R/V Tangaroa, Stn. TAN 0 116, 10 October 2001, 2786– 2821 m. NMNZ P.038023/1, cleared and stained right pectoral girdle.

Comparative material. P. kreffti Paratype ZIN 46826, male, 96 mm SL, 54°12' S, 40°02' W, Shag Rocks, South Georgia, FR/V Walther Herwig, Stn. 97–II /76, 3 January 1976, 2600 m.

Diagnosis. Vertebrae 79, dorsal fin rays ~71, anal fin rays ~ 67, pyloric caeca 5 or 6. Teeth simple, sharp, lanceolate. HL 19% SL. Gill opening completely above the pectoral fin. Tail long, slender. Radials two (2+0+0), round, unnotched; scapula and coracoid helves long. Stomach black, pyloric caeca brown.

Description. Counts: V 79, D ~ 71, A ~ 67, C 5, P 17–18, radials 2, pc 5 or 6, pores unknown. Ratios: HL 19.3% SL, E 5.5, orbit 6.2, uj 9.9, go 4.2, UPL 14.1, preD 22.7, preA 29.4, ma 15.1, aAf 14.5, pabd 18.7. In % HL: E 28.7, orbit 32.3, uj 51.4, go 21.9, UPL 73.2, preD 117.8, preA 152.6, aAf 75.3, pabd 97.2.

Head small, short, dorsal profile almost flat, sloping evenly downward anteriorly at an angle of about 45° to snout. Snout damaged, blunt, apparently slightly protruding. Nostrils damaged, apparently close to eye and above level of mid pupil. Mouth horizontal, terminal; oral cleft extending almost to below posterior margin of orbit, upper jaw extending to below rear of eye. Teeth in both jaws lanceolate, sharp canines, in about 23 irregular oblique rows of up to four teeth each. Symphyseal gap present in upper jaw, almost forming a notch into which symphysis of lower jaw fits. Symphysis of lower jaw with a distinct knob. Eyes damaged, pupil apparently large. Gill opening completely above pectoral fin base, relatively long; opercular flap lobate, formed by broad, dorsally curved opercle. Pore formula unknown, chin pores apparently moderately large, separated by symphyseal knob.

Pectoral fin probably deeply notched, upper ray about on horizontal above lower margin of orbit. Upper lobe rays reaching distinctly behind end of abdominal cavity and origin of anal fin; lower lobe ray lengths unknown. Pectoral fin with 11+2–3+4 rays, none rudimentary; spacing of notch rays very wide, much wider than that of upper and lower lobe rays. Pectoral girdle strongly cartilaginous and poorly calcified, difficult to stain with alizarin. Radials 2 (2+0+0) round, unnotched. Scapula and coracoid both with long helves. Coracoid notch absent.

Trunk low, tail elongated. Vertebrae 9+70. Dorsal fin origin between vertebrae 4–5; anal fin origin between vertebrae 8–9. Anus anterior to gill opening, below anterior end of opercle. Abdominal cavity unusually short, its length only about 19% of SL behind pectoral symphysis. Pyloric caeca apparently four, digitate. Tail unusually long, tapering to an almost filamentous end. Hypural completely fused; caudal of 1+2/2 rays, their bases occupying entire margin of hypural.

Color of body unknown, almost entirely skinned; shreds of remaining thin translucent skin suggest it was dark brown. Head darker, its sides and lower jaw black, probably reflecting entirely black jaws, gums, and orobranchial cavity. Peritoneum and stomach black, pyloric caeca brown.

Distribution. Known from a single specimen collected in the Bounty Trough at 2786–2821 m.

Etymology. From the Greek pseudes, false, and kreffti , the specific epithet of Paraliparis kreffti , the species most similar to it.

Comparisons. The new species is similar to P. k re ff t i Andriashev 1986 —so similar that it merits the name P. pseudokreffti . It has only two radials, four principal caudal fin rays, a similar pectoral fin ray arrangement, and a black peritoneum and stomach. The proportions of the two species are also similar. It differs and is clearly distinct from P. kreffti in having 79 (9+70) vertebrae (vs 71–77), D~71 (vs 64–66), ~A 67 (vs 59–60), fewer pyloric caeca (5 or 6 vs 9), a slightly shorter head (19 vs 21–23% SL), scapular helve shape (long vs short and stout), gill opening (completely above the pectoral fin vs above and extending ventrally over 1–3 rays), and more elongate tail. Finally, it is from the Bounty Trough, east of New Zealand, whereas P. kreffti is known from the opposite side of Antarctica in the Weddell Sea and the Antarctic Peninsula. Paraliparis pseudokreffti is also similar to P. bipolaris Andriashev 1997 from the northeast Atlantic (considered by Andriashev, 2003: 300, as a sister species to P. k re f f t i), but differs from it in having more vertebrae (79 vs 76–77), a smaller eye (28 vs 35% HL), longer upper jaw (51 vs 42% HL), and many other proportions just outside those of P. bipolaris .

Paraliparis pseudokreffti differs from all the Australian species with two radials (see Stein et al. 2001) in number of vertebrae and fin rays: vertebrae (79 vs 66–69), dorsal fin rays (~71 vs 60–64), anal fin rays (~67 vs 53–57), pectoral fin rays (17–18 vs 19–22), and caudal fin rays (4 vs 8).

Comments. Andriashev (2003) redescribed P. kreffti based on new material that differed significantly in some regards from the types (which were juveniles) but that he considered to be adults. I suggest that P. pseudokreffti , P. kreffti , and P. b i po la r is form a group whose precise relationships remain to be clarified when more material becomes available.

Figures

FIGURE 23. Paraliparis pseudokreffti n. sp. Holotype. NMNZ P. 038023, 128 mm SL. A. lateral view; B. NMNZ P. 038023 / 1, right pectoral girdle.