First Japanese record of Conocara fiolenti (Alepocephalidae) collected from Hyuga-nada, Japan

Abstract

The family Alepocephalidae, comprising about 18 genera and at least 95 species of benthic and pelagic deep-sea fishes, includes 10 species of the genus Conocara, known from about 800 to more than 5000 m depth in the Indo-Pacific and Atlantic Oceans. Conocara is characterized by the dorsal-fin origin located posterior to the anal-fin origin, the dorsal-fin base shorter than the anal-fin base, the body covered with small scales (>80 in longitudinal row above lateral line), tubular lateral line scales, maxilla toothless, upper jaw equal to or longer than snout and photophores absent. A single specimen of Conocara fiolenti Sazonov and Ivanov, 1979, collected from Hyuga-nada, Japan in a depth of 1453– 1481 m, on 3 April 1991, is distinguished from all congeners by the following combination of characters: dorsal-fin rays 22, anal-fin rays 28, gill rakers absent on upper limb, number of scales in longitudinal series above lateral line ca. 220, length of anal-fin base 22.7% SL, predorsal-fin length 68.2% SL, head length 29.2% SL, orbital diameter 6.6% SL, anterior margin of premaxilla lacking a bony ridge and posterior margin of maxilla extending beyond anterior margin of eye. Conocara fiolenti has been previously recorded from tropical and temperate zones of the Indian, western Pacific and Atlantic Oceans. However, the present specimen represents the first record from Japanese waters and northernmost record in the Pacific Ocean. The new Japanese name “Maru-kuchi-yajiri-iwashi” is proposed for the species.