A rare grenadier Coryphaenoides yaquinae (Pisces: Gadiformes: Macrouridae) from the eastern North Pacific

초록

The grenadiers family Macrouridae encompassing about 27 genera, about 350 species, and most species are benthopelagic occurring in tropical and subtropical latitudes, and lives at depth between 200 and 6,400 m. The genus Coryphaenoides comprising about 61 species, and is defined by a combination of the following characters: branchiostegal rays 6; anus immediately before anal fin origin; chin barbel present; head covering tough, opaque, mostly covered with spinulated scales; scales usually fewer than 10 below midbase of first dorsal fin; dentition from broad bands to 1 or 2 rows; second spinous ray (spine) of first dorsal fin usually slightly prolonged and serrated along leading edge; pelvic fin rays 6 to 14. Coryphaenoides yaquinae was described by Iwamoto and Stein (1974) from Tufts Abyssal Plain, at a depth of 3724m, collected by C.L. Hubbs et al. in July 1967. This species is usually distributed at depths of about 2500-6945 m in the North Pacific and eastern south Atlantic. The few specimens were known owing to an inhabitant of greater depths. A single specimen of the species was collected from the eastern North Pacific at 10°32′4″N, 131°55′4″W during the Korea Deep Ocean Study (KODOS) of the KIOST in February 2014 by a Bait-trap Lander around 5,100 m depth. C. yaquinae distinguished from congeners by the following combination of characters: pelvic fin rays 10; almost all surfaces of the body and the dorsal surface of the head coarsely scaled, but the ventral surface of head and mandible completely naked; premaxillary teeth usually two or more irregular rows, outer series much enlarged; mandibular teeth two irregular rows near symphysis, and of one distinct row posteriorly; scale rows below suborbital ridge and on mandibular rami usually absent; inhabiting deeper than 4300 m depth. Color when fresh grayish brown to blackish. New Korean name for C. yaquinae is proposed as Sim-hae-gin-ga-si-min-tae.