Coelorinchus macrochir ( Günther, 1877 )

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 : 61-62

Coelorinchus macrochir ( Günther, 1877)

Figure 7 .

Macrurus macrochir Günther, 1877:438 (holotype, BMNH 1887.12.7.123; off “Inoshima” [= Enoshima], Japan, Challenger sta. 232, 345 fm [631 m]).

Abyssicola macrochir : Goode and Bean, 1896:417 (compiled, type-species for new genus Abyssicola ).— Gilbert and Hubbs, 1916:183–184–186 (36 spec., 91–634 mm TL; Pacific coast of Japan, 129–437 fm [236–799 m]).— Okamura, 1970:145–148, pl. XXXII, text-fig. 58 (136 spec., 173–680 mm TL; Japan: Hokkaido to East China Sea off Kagoshima Prefecture).— Okamura in Masuda et al., 1984:96, pl. 82–G (compiled).— Okamura in Okamura and Kitajima, 1984:221, 364 (1 spec., 590 mm TL; Okinawa Trough, 820 m).— Nakabo, 2002:429 (compiled).

Coelorhynchus (Abyssicola) macrochir : Gilbert and Hubbs, 1920:425 (in key).

Coelorinchus macrochir : Iwamoto, 1990:171 (compiled).— Shao et al., 2008: table 2 (2 spec., NET, 100–650 m; first record from Taiwan).— Honma et al., 2008:65–74 ( Japan Sea).— Kim et al., 2009:110–112, fig. 5, table 2 (East Sea [ Japan Sea], Korea).

MATERIAL EXAMINED (2 spec.).— NET: ASIZP 65574 (1, 424 TL) , Da-xi; ASIZP 66972 (1, 570 TL) , Da-xi.

DISTINGUISHING FEATURES.— 1D II, 9–11; P i16–i20; GR-I (inner) 10–12 total; scales below midbase 1D 4.5–6.0, below 2D 5.5–7.0; pyl.caeca 42–48. Snout rather bluntly conical to rounded in lateral profile, length 29–36% HL, anterolateral margin of snout incompletely supported by bone; a distinct curve in anterior portion of suborbital ridge; orbit 27–33% HL; mouth relatively large, upper jaw 34–42% HL. Nasal fossa and underside of head scaly; spinules on body scales short, broad, in 4–9 widely divergent rows. Vent about midway between pelvic-fin base and anal-fin origin; naked fossa of light organ close before vent (Group II of Iwamoto, 1990). Ground color brown, bluish ventrally on trunk; mouth and gill cavities blackish; fins dusky to blackish. Attains at least 680 mm TL.

DISTRIBUTION.— Pacific coast of Japan (Hokkaido to Kyushu off Kagoshima), s. Okhotsk Sea , East China Sea (including Okinawa Trough ), Japan Sea off Niigata, ne. Taiwan, and the Philippines, in 235–830 m.

REMARKS.— Shao et al. (2008: table 2) first recorded the species from Taiwan based on the two specimens listed above; they represent the southernmost record (lat. 24.8°N) of the species. Most previous workers have included Coelorinchus macrochir in its own genus, Abyssicola Günther , based primarily on its dentition: short conical teeth in three series in premaxilla, in two series in dentary. Okamura (1970:143–144) provided a lengthy diagnosis that readily differentiated the species from the 14 then-known Japanese species of Coelorinchus . However, when viewed on a worldwide basis of more than 100 species in the genus, the diagnostic characters enumerated by Okamura are shared by one or more species of Coelorinchus sensu lato and thus fail to differentiate Abyssicola . Fukui et al. (2010) conducted a detailed study of the eggs and larvae of C. kishinouyei , and using DNA nucleotide sequences, provided a (op. cit. fig. 3) phylogenetic tree which showed C. macrochir deeply nested within other Japanese Coelorinchus , with its sister group being C. anatirostris / productus (which they considered as synonyms: see Remarks under C. productus ).

Figures

FIGURE 7. Coelorinchus macrochir (Gunther, 1877). ASIZP 55972, 570 mm TL, preserved.