Pseudonezumia pusilla (Sazonov and Shcherbachev, 1982)

Iwamoto, Tomio, Nakayama, Naohide, Shao, Kwang-Tsao & Table, Hsuan-Ching Ho, 2015, Synopsis of the Grenadier Fishes (Gadiformes; Teleostei) of Taiwan, Proceedings of the California Academy of Sciences 62 (3), pp. 31-126 : 98-99

Pseudonezumia pusilla (Sazonov and Shcherbachev, 1982)

Figures 22A–B .

Paracetonurus pusillus Sazonov and Shcherbachev, 1982:12–14 , fig. 4 (holotype, ZMMU P.15306, Indian Ocean , Ninety-East Ridge , 11°24.3ʹS, 88°50ʹE, 1500–1600 m; 17 paratypes, Indian Ocean and w. Pacific off New Guinea; 1380–2000 m)

Paracetonurus cetonuropsis (non Gilbert and Hubbs, 1916): Shao et al., 2008: table 2 (3 spec., Taiwan [ SCS], 1098 m).

Pseudonezumia pusilla : Iwamoto and Williams, 1999:208–209, fig. 45 (1 spec., off Western Australia, w. of NW Cape; 1460–1500 m).

MATERIAL EXAMINED (5 spec.).— SCS: ASIZP 66945 (3, 137–163 TL) and ASIZP66424 (1, 234 TL) , CD 322, 1098 m. Other material: CAS 224176 (1, 28.6 HL; 175+ TL) , SCS, off Vietnam, 15°38ʹN, 111°54ʹE ; MV Stranger , NAGA Exped. , sta. 60–67 , GVF Reg. no. 2083, 28 Feb. 1960 .

DISTINGUISHING FEATURES.— 1D II,8–9; P 17–18; V 6 or rarely 7; total GR-I (outer/inner) 10–12/10–11; GR-II 10–12/10–11; pyl. caeca 7–12. Snout length 29–32% HL; preoral length 21–22%; internasal width 23–26%; interorbital 30–33%; orbit 29–31%; posterior nostril 12–16%, 2.2–2.7 times into orbit; suborbital 14–18%; postorbital 41–46%; orbit to preop. 35–42%; upper jaw 34–40%; barbel 12–20%; outer gill-slit 12–20%; pre-A 122–138%; isth. to A 57–72%; outer V to A 35–52%; 1D-2D 22–46%; length base 1D 21–29%. Head relatively compressed, deeper than wide; snout pointed, rather broad, internasal width about 1 ⁄ 4 HL; interorbital 1 ⁄ 3 HL, slightly greater than orbit diameter; suborbital about half orbit; barbel relatively long, slender. Margin of preopercle broadly rounded, almost vertical posteriorly, preopercle ridge rounded at angle. Origin of V under posterior margin of preopercle; vent slightly removed from origin of A, under anterior 1 ⁄ 4 of 1D. Posterior end of upper jaw below mid-orbit. Scale spinules 2–9, awl-shaped, erect to slightly reclined. Periproct small, slightly removed from A origin. Paired fins small, weak; 1D spine with weak, widely spaced denticles. (In part from Sazonov and Shcherbachev 1982:12–13.)

DISTRIBUTION.— Known from the holotype and 17 paratypes taken in the Indian Ocean and w. Pacific off New Guinea (Bismark Sea); one specimen from off the NW Cape of Australia; and the current Taiwan specimens from the South China Sea, which extend the range of the species into the w. North Pacific. Depth range 1098–2000 m; the Taiwan specimens represent the shallowest recorded at 1098 m.

REMARKS.— Shao et al. (2008: table 2) first recorded the Taiwan specimens as Pseudonezumia cetonuropsis , a species known only from the holotype and small paratype taken off central Japan. That species differs from P. pusilla in having a much shorter barbel (6% HL), longer snout (35%), and smaller orbit (27%).

Figures

FIGURE 22. Pseudonezumia pusilla (Sazonov, and Shcherbachev, 1982). ASIZP66424, 234 mm TL. A. fresh. B. lateral view of left head, preserved.