Author: (Tanaka, 1909)
One of several Apristurus with the first dorsal fin half area of second or less. See diagnostic features and key to species for further characters.
Body relatively slender, trunk slightly tapering toward head. Snout moderately long, broad, and bell-shaped, preoral snout about 8% of total length; gill slits small, less than eye length; gill septa without projecting medial lobes or pleats, not strongly incised; eyes rather small in adults; about 3% of total length; nostrils broad, their width about 1.2 times internarial space; incurrent and excurrent apertures narrowly oval, anterior nasal flaps low and angular; mouth short, moderate-sized, and broadly arched, with dental bands little expanded and with lower one falling just behind uppers; mouth and labial furrows mostly below ovoc- Inhinl fnidc nnt PnlarnPd with Inwars diannnal to body axis. Interdorsal space about twice first dorsal base, slightly less than preorbital snout; first dorsal fin about half as large as second, base of first about two-thirds length of second; origin of first dorsal posterior to pelvic insertions; second dorsal insertion well in front of anal insertion; pectoral fins moderate-sized, anterior margins about 14% of total length; inner margins long, nearly length of pectoral bases; interspace between pectoral and pelvic bases short, sligthly less than prespiracular length and about 10% of total length in adults; pelvic fins fairly high and broadly rounded; anal fin long, low and subangular, about five times as long as high, base slightly greater than prebranchial space and 19% of total length in adults; caudal fairly broad, without a dorsal crest of enlarged denticles. Lateral trunk denticles of body with crowns flat and closely imbricating, surface smooth and without a feltlike or fuzzy texture. Colour probably dark, without conspicuous markings. Adults moderately large, adult female 64 cm.
Western North Pacific: Japan (Honshu).
Habitat and Biology:
A little-known deepwater species of the continental slopes. Oviparous, probably one egg per oviduct laid at a time.
Maximum about 80 cm.
Interest to Fisheries:
None at present.
Holotype: Imperial University collection, Tokyo, Japan, no. 2154, 800 mm male, presumably adult. Type Locality: Off Japan.