Coelorinchus cf. macrorhynchus, Smith and Radcliffe, 1912

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 : 62

Coelorinchus cf. macrorhynchus [sensu Smith and Radcliffe, 1912]

Figure 8.

MATERIAL EXAMINED.— SWT: ASIZP 65531 (1, 73.0 mm HL, 222 mm TL), CD 138, 441 m.

Distinguishing feature.— 1D II 9; P i18–i19; GR-I (inner) 2+6, GR-II (outer/inner) 0+6 / 1+7; scales below midbase 1D 4.5, below 2D 6.5, lateral-line scales over distance equal to pre-D length 47. Snout sharply pointed, slender and spear-shaped in dorsal view, length 51% HL; anterolateral margin of snout completely supported by bone; orbit 23% HL, 2.2 in snout length, upper jaw 23% HL; nasal fossa densely scaled anteriorly and ventrally; underside of head almost fully scaled (scales with 1–3 short rows of spinules). Light organ group II of Iwamoto (1990), fossa narrow and short, not extending to pelvic-fin bases. Anus separated from A origin by 2 or 3 scale rows. Spinules on body scales blade-like in 3–6 sharp, divergent, ridgelike rows, closely overlapping, with height increasing abruptly with posteriormost spinule much larger than anterior ones. Ground color brownish (somewhat faded), bluish over abdomen but not on chest; mouth and gill cavity dark; most fins dark dusky to blackish. Attains more than 44 mm TL.

DISTRIBUTION.— Broadly distributed from Philippines to e. and w. coasts of Australia, in 485–1107 m. In Taiwan, the single specimen was collected in 441 m.

REMARKS.— This single juvenile was captured in the same haul as two specimens ( ASIZP 65523, 250– 265 mm TL) that we identified as C. smithi . It differed from those specimens in having a more slender and longer snout (orbit 2.2 into snout, cf. 1.3– 2.1 in C. smithi ), slightly narrower internasal and interorbital widths (16% HL and 18% HL, respectively, cf. 17–19% and 19–23% in C. smithi ) and the nasal fossa was almost fully covered with small scales antero-ventrally (naked to sparsely covered in C. smithi ). The differences are so slight that we are uncertain whether they simply represent individual variation; thus, our identification must be considered as tentative. The presence of this species in Taiwan waters should not be surprising, however, as it was originally described from captures in the Philippines in the Verde Island Passage off sw. Luzon. If confirmed, this specimen represents the first record of the species from Taiwan.

Figures

FIGURE 8. Coelorhynchus cf. macrorhynchus [sensu Smith and Radcliffe, 1912]. ASIZP65531, 222 mm TL. A. lateral view. B. dorsal view of head. C. ventral view of head.