Author: Abe, 1966
Field Marks:
No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniform dark coloration except for white-tipped fins, long abdomen and short caudal peduncle, wide-spaced denticles on body.
Diagnostic Features:
Body stout and compressed. Preoral snout moderately long, about 3/5 of distance from mouth to pectoral origins; mouth extremely short and very broadly arched, less than a third as long as wide. Second dorsal fin slightly larger than first; pectoral apices when laid back fall well anterior to first dorsal spine origin. Caudal peduncle short, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to third gill slits. Lateral trunk denticles widespaced and sparse on body, which is almost naked, conical and with hooked cusps. Colour uniform blackish. Size moderate, adults to about 44 cm.
Geographical Distribution:
Western North Pacific: Japan (southeastern Honshu).
Habitat and Biology:
A little-known deepwater dogfish, depth not reported.
Size:
Maximum total length reported 44 cm, females mature at 42 to 44 cm, males unknown.
Interest to Fisheries: None.
Type material:
Holotype: Zoological Institute, Faculty of Science, University of Tokyo no. 52310, 440 mm adult female. Type Locality: Suruga Bay, off Yaizu, Honshu, Japan.