Coelorinchus Giorna, 1810

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 : 47-48

Genus Coelorinchus Giorna, 1810

DISTINGUISHING FEATURES.— BR 6; suborbital ridge formed of stout, coarsely spined, modified scales extending continuously from tip of snout to posterior angle of preopercle, ending in a sharp point; second spinous ray of first dorsal fin smooth along leading edge (some juveniles and exceptional adults may have a few spinules near distal tip); ventral light organ variously developed, from small gland anterior to anus not externally visible, to large prominent organ with one or two dermal fossae along ventral midline; no rakers along outer (lateral) side of first gill arch. V almost always 7, rarely 6.

REMARKS.— The most diverse genus of family Macrouridae with more than 118 recognized species, categorized by some into as many as seven subgenera; 23 species known from Taiwan. Relationships closest to Macrourus , the only significant differences between the two genera the presence of denticulations on spinous second ray of 1D and generally more pelvic fin rays (8 or 9, rarely 7) in Macrourus . Preliminary cladistic analysis (e.g., Roa-Varón and Ortí 2009:700) suggests that Macrourus is deeply nested within Coelorinchus , a situation that could prove to be a nomenclatural nightmare. Greatest diversity found in tropical regions of the Indo-West Pacific. Species most common in upper- to middle-slope waters between 200 and 1000 m, although some species range into shallow continental-shelf depths and others into depths greater than 1000 m. Many species of shallower waters are highly restricted in their geographic distribution. Maximum size attained range from about 20 cm TL to more than 87 cm.

In statements concerning the ventral light organ, Groups I through IV refer to categories assigned by Iwamoto (1990) based on the external development of the dermal window of the light organ.