Coelorinchus japonicus (Temminck and Schlegel, 1846)

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 : 57-58

Coelorinchus japonicus (Temminck and Schlegel, 1846)

Macrurus japonicus Temminck and Schlegel, 1846:256 , pl. 112, fig. 2, 2A–B (bays in provinces Oomura and Shimabara, Japan. Lectotype: RMNH 3476 . Paralectotypes: RMNH D1405–1406 [2 stuffed]).

Coelorhynchus japonicus : Gilbert and Hubbs, 1916:178–179 (5 spec., 158–307 mm TL; Japan).— Okamura, 1970:183–186, pl. XL, text-figs. 78, 79 (93 spec., 138–656 mm TL; range given as “tropic and subtropic regions of Indo-western Pacific including southern part of Japan ”).— Yatou in Okamura et al., 1982:181, photo 106, 353 (8 spec., 438–750 m TL, 300–700 m).

Coelorinchus japonicus : Okamura in Masuda et al., 1984:98, pl. 83–D.— Yatou in Okamura and Kitajima, 1984:231, photo 163, 367 (10 spec., 315–680 mm TL, 560–1000 m).— Xiong, et al., 1988:190–192, fig. 152 (4 spec., 275–373 mm TL; East China Sea, 490–716 m).— Iwamoto, 1990:162–163, fig. 378.— Shen et al., 1993:169 (descr.).— Kim et al,. 2005:172 ( Korea).— Shao et al., 2008: table 2 (3 spec., NET, 100–650 m).

Caelorinchus japonicus : Chiou et al., 2004b:36, 47 (in key, list).

MATERIAL EXAMINED (7 spec.).— NET: ASIZP 56349 (1, 292 TL) , Da-xi; ASIZP 65567 (1, 370+ TL) , Da-xi; ASIZP 63280 (2, 370–600 TL) , Da-xi; ASIZP 70216 (2, 363–450 TL) , Da-xi; CAS 214622 (1, 300 TL) , Da-xi.

DISTINGUISHING FEATURES.— 1D II, 8–10; P i16–i20; GR-I (inner) 7–9 total; scales below midbase 1D 4.5–6.0, below 2D 5.5–7.5; pyl.caeca 41–60. Snout produced and sharply pointed, length 40–48% HL; anterolateral margin of snout completely supported by bone; orbit 22–30% HL, upper jaw 23–29% HL. Nasal fossa scaled ventrally; underside of head, including mandibular rami scaly; most head scales with single crestlike spinule row; body scales with broadly triangular spinules lacking strong transverse buttresses, arranged in 3–7 slightly divergent, sharply crestlike rows. Head ridges stout, heavily spinulated. Light organ short, Group I of Iwamoto (1990). Ground color brownish to grayish, paler below, darker over abdomen and gill covers; gular and BR membranes pale, lips white, mouth and gill cavities blackish; fins blackish to light dusky. Attains at least 750 mm TL. (Description mostly after Okamura, 1970.)

DISTRIBUTION.— From s. Japan (including Japan Sea ), East China Sea (Okinawa Trough), to ne. Taiwan; 100–1000 m, but most abundant off Japan between 300 and 600 m.

REMARKS.— A large species with a substantial vertical distribution. One of the few grenadiers recorded as occurring in the Japan Sea, although that record is questionable and must be verified (see Kim et al. 2009:113). Among the Taiwan Coelorinchus with short light organ immediately anterior to A origin, C. japonicus is distinguished by the combination of anterolateral snout margin completely supported by bone, scales on underside and top of head with spinules in one crestlike row, and body scales with broad spinules in 3–7 sharp crestlike rows.