Trachonurus sentipellis Gilbert and Cramer, 1897

Figures 25A–C.

Trachonurus sentipellis Gilbert and Cramer, 1897:429 (syntypes SU 3140 and USNM 51689; Hawaiian Is., 21°12ʹ00ʺN, 157°38ʹ30ʺW, Albatross sta. 3474, 375 fm [686 m]).— Iwamoto, 1997:945.— Iwamoto and Merrett, 1997:551.— Iwamoto and Williams, 1999:213 (descr., w. and se. Australia).— Merrett and Iwamoto, 2000:775 (6 spec., New Caledonia, 764–1,050 m).— Iwamoto and Graham, 2001:495 (3 spec., se Australia, 940–1130 m).— Shao et al., 2008: table 2 (7 spec., Taiwan [SWT, SCS], 441–1040 m).

MATERIAL EXAMINED (10 spec.).— SWT: ASIZP 64232 (2, 54.6–61.0 HL, 265+-295+ TL), CD 193, 821 m; ASIZP 65539 (1, 59.9 HL, 305 TL), CD 134, 736– 1040 m; ASIZP 65543 (1, 150 TL), CD 138, 441 m; ASIZP 65544 (1, 175 TL) and ASIZP 65548 (1, 135 TL), CD 203, 634– 866 m; ASIZP 65637 (1, 310+ TL), CD 229, 880– 1062 m . SCS: ASIZP 66150 (1, 49 HL, 250+ TL), CD 321, 954 m; ASIZP 66743 (2, 21–32 HL, 105+-170+ TL), CD 320, 731 m.

DISTINGUISHING FEATURES.— 1D II,6–8; P 15–16 (rarely 18); V 7; total GR-I (inner) 11–13; scale rows below origin 2D usually 6–7, below midbase 1D 5–7; lateral line scales over distance equal to pre-1D length 26–34; scale rows between V base and gill cover 8–9; pyl. caeca 9–13, short, thick. Snout length 23–26% HL; interorbital width 26–33%; orbit diameter 27–37%; suborbital width 8–12; postorbital length 38–53%; orbit-preopercle 26–33; upper jaw 28–37%; barbel 8–11%; 1D-2D interspace 11–29%. Grooved lateral line present; body scales relatively large, coarsely covered with stout, erect spinules. Jaw teeth all small. Attains more than 31 cm TL. (Adapted from Iwamoto 1997.)

DISTRIBUTION.— Hawaii, Australia, New Caledonia, and Taiwan in 441–1130 m. Specimens from Taiwan were all taken from the South China Sea in 441–1040 m; they represent the first record of the species from the w. North Pacific.

REMARKS.— Trachonurus sentipellis is closely similar to T. robinsi Iwamoto, 1997 from the Philippines, but that species shows differences in some meristic values: P rays 10–14 vs. 15–16; inner GR-I 9–11 vs. 11–13; scales below 2D origin 4–6 vs. 5–8 (usually 6–7). Also, where T. sentipellis almost invariably has V 7, in T. robinsi the count is more often 6 than 7, and the maximum size in T. robinsi probably does not exceed 25 cm, whereas T. sentipellis exceeds 31 cm.