Author: Nakaya, 1975
An Apristurus with an extremely long abdomen and short snout.
Body relatively slender, trunk slightly tapering toward head. Snout moderately long, broad, and bell-shaped, preoral snout about 7 to 8% of total length; gill slits moderately large, somewhat longer than eye length; gill septa not incised or pleated, with or without short projecting medial lobes; eyes rather small in adults, about 2.4 to 3% of total length; nostrils fairly broad, their width about 1.4 times in internarial space; incurrent and excurrent apertures narrow and oval, anterior nasal flaps broadly triangular; mouth long, large, and broadly arched, with dental bands prominently expanded and with lower ones falling well behind uppers: mouth and labial furrows extending well in front of eyes, iabial folds not greatly enlarged, with lowers diagonal to body axis; teeth not greatly enlarged in males, but with slenderer cusps. Interdorsal space slightly less than 1.5 times first dorsal base, subequal to preorbital snout; first dorsal fin about two-thirds as large as second, bases about equally long; origin of first dorsal over last half of pelvic bases; second dorsal insertion in front of anal insertion; pectoral fins moderate-sized, anterior margins about 11 to 14% of total length; inner margins long, nearly the length of pectoral bases; interspace between pectoral and pelvic bases long, almost equal to prepectoral length and about 16% of total length in adults; pelvic fins high and broadly rounded; anal fin moderately long, high and rounded, between 2.5 and 3 times as long as high, its base somewhat greater than prespiracular space and 13 to 15% of total length in adults. Lateral trunk denticles of body with crowns widespaced, fairly flat. Colour blackish-brown. Adults large, 63 to 71 cm.
Known only from off Chiba Prefecture, Honshu, Japan.
Habitat and Biology:
An abundant deepwater bottom shark off Chiba Prefecture, but biology little-known. Oviparous.
Adult females reach at least 63 cm, adult males 65 to 71 cm.
Interest to Fisheries:
Commonly taken by trawl off the type locality, and possibly utilized for oil, human consumption and fishmeal or fish cakes locally.
Data from Nakaya (1975); this species was not examined by the writer.
Holotype: Hokkaido University Laboratory of Marine Zoology, HUMZ 40082, 697 mm adult male. Type Locality: Cape Daito, Chiba Prefecture, Honshu, Japan, western Pacific.