Coelorinchus formosanus Okamura, 1963

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 : 54-55

Coelorinchus formosanus Okamura, 1963

Coelorhynchus formosanus Okamura, 1963 (Mar.):37 (holotype FAKU 35856, Da-xi, Taiwan; 4 paratypes, FAKU 35857–60).— Okamura, 1970:161–165, pl. XXXIV, text-figs. 65, 66 (descr. from type specimens).

Coelorhynchus intermedius Chu and Lo in Chu, Chan and Chen, 1963 (Aug.):173, fig. 139 (East China Sea).— Xiong, Zhan, and Deng 1988:187–188, fig. 148 (4 spec., 164–238 mm TL; East China Sea off Ryukyu Is., 28°48ʹN, 127°00ʹE, 213–285 m).

Coelorhynchus abbreviatus Chu and Lo in Chu, Chan and Chen, 1963 (Aug.):174 (East China Sea).

Coelorinchus formosanus : Okamura in Masuda et al., 1984:97, pl. 82–J.— Shao et al., 2008: table 2 (9 spec., NET, SCS, SWT, 600–1110 m).

Caelorinchus formosanus : Iwamoto, 1990:158 (descr.). Shen et al., 1993 (descr.).— Chiou et al., 2004b:37, 47 (in key, list).

MATERIAL EXAMINED (38 spec.).— NET: FAKU 35836 (holotype), Da-xi ; FAKU 35857 (paratype), Da-xi ; ASIZP 57976 (1, 184 TL) , Da-xi; ASIZP 61048 (1, 220 TL) , Da-xi; ASIZP 61342 (1, 272 TL) , Da-xi; ASIZP 65584 (3, juveniles) , CP 119, 123– 140 m; ASIZP 65650 (1, 251 TL) , Da-xi; ASIZP 65661 (1, 260+ TL) , Da-xi; ASIZP 65664 (1, 310 TL) , Da-xi; ASIZP 61342 (1, 272 TL) , Da-xi; ASIZP 70693 (5, 224–333 TL) , Da-xi; ASIZP 70714 (1, 154 TL) , Da-xi; CAS 214457 (2, 278–297 TL) , Su-ao; CAS 224169 (1, 242 TL) , Da-xi. SWT: ASIZP 65595 (4, 215–305 TL) , CD 141, 985– 1110 m; ASIZP 65822 (1, 218 TL) , Dong-gang; ASIZP 58024 (1, 173 TL) , Dong-gang; ASIZP 62195 (1, 168 TL) , Dong-gang; ASZIP 62196 (2, 156–160 TL) , Kaoshiung; ASIZP 62197 (2, 260–297 TL) , Dong-gang; ASIZP 70661 (3, 84–165 TL) , Dong-gang. NT: ASIZP 61009 (1, 215 TL) , Jin-shan; ASIZP 65568 (1, 326 TL) , Da-xi. No data: ASIZP 65578 (1, 322 TL).

DISTINGUISHING FEATURES.— 1D II, 8–10; P i15–i18; GR-I (inner) 7–9 (total); scales below midbase 1D 3.5–4.5, below 2D 3.5–4.5; pyl.caeca 9–12. Snout sharply pointed, length 42–45% HL, anterolateral margin snout incompletely supported by bone; orbit 22–26% HL, 1.5–2.0 in snout; upper jaw 28–35% HL. Nasal fossa and broad areas anteriorly and laterally atop snout almost entirely naked; underside of snout naked except along anterolateral margins where scales broadly overlap edge; underside of head behind mouth and mandibular rami scaly; short triangular spinules on body scales in irregularly quincunx to widely divergent rows. Light organ long, extends forward to near isthmus, Group IV. Ground color brownish to grayish, irregular darker blotches over dorsal portions of body, silvery ventrally; fins dark or dusky; mouth whitish, gill cavities, gular and branchiostegal membranes, and jaws dark dusky; 1D black along leading edge, dark on basal half or so, V and A blackish distally. Attains at least 326 mm TL. (Adapted from Okamura 1970, with additions from current material.)

DISTRIBUTION.— Known from East China Sea e. of Amami Is. ( Ryukyu Islands ) and Taiwan ( NET, SWT, and SCS) in depths between about 100 and 600 m. Most abundant in 100–400 m.

REMARKS.— Coelorinchus formosanus is the most abundant grenadier species in Taiwan in depths less than 600 m (Wu 2002). Among the Group IV species of Coelorinchus of Taiwan, it is alone in having a scaly posterior underside of head. Okamura (1970:151) synonymized without comment C. intermedius Chu and Lo, 1963 and C. abbreviatus Chu and Lo, 1963 with C. formosanus . Xiong et al. (1988:148), however, considered C. intermedius as distinct, based on lesser amounts of scaly areas under the head and below the nasal fossa in the latter species. We have not been able to verify this with comparative material. They also provided no comment on the status of C. abbreviatus , suggesting agreement with Okamura’s assessment of the nominal species.