A new species of the grenadier genus Coelorinchus from the Hawaiian-Emperor seamount chain (the Pacific Ocean) (Teleostei, Gadiformes, Macrouridae)

Abstract

In this paper, a new species, Coelorinchus idiolepis, is described from the Hawaiian-Emperor seamount chain in the Pacific Ocean. It is similar to C. anisacanthus from the Emperor seamount chain; however, it differs from the latter in the proportions of its head, in the shorter pelvic fins, and in the details of pigmentation. A key for identification of the species of Coelorinchus from the Hawaiian-Emperor seamount chain is also presented. Diagnosis of the new grenadier species: a member of the “C. acanthiger” group (sensu Prokofiev, Iwamoto 2020) with underside of head completely scaleless; dorsal surface of snout with narrow scaleless areas laterally from medial nasal ridge; dorsal contour of snout straight, sides only slightly convex in dorsal view; snout length 2.6 times in HL, eye length 1.2–1.3 times shorter than postorbital length; upper jaw reaching the posterior third of the eye; pelvic fin (with filament) about ¼ of head length; spinule rows on top of head in several divergent rows; spinule rows on flank scales variably developed, medial row more or less enlarged, lateral rows sometimes reduced, disappearing in smaller specimens, spinules in rows greatly depressed, with wide buttresses not forming transverse ridges.