Author: Nakaya, 1975
A large Galeus with an unusually short anal fin, long space between anal and pelvic bases, prenarial snout longer than the eyes, and, in males, slender, greatly elongated claspers.
Precaudal tail not noticeably compressed at base. Snout moderately long and pointed, preoral length about 7% of total length; prenarial snout greater than eye length; eyes probably nearly lateral, with subocular ridges obsolete; mouth fairly large and long, broadly arched, its width 6 to 8% of total length; labial furrows moderately long, not confined to mouth corners. Pelvic fins large, low, and angular; interspace between pelvic and anal bases considerably longer than anal base; anal base short, 8 to 10% of total length, much less than interdorsal space; its origin varying from below to behind midlength of interdorsal; no suboaudal crest of enlarged denticles on preventral caudal margin. A variegated colour pattern of obscure and poorly defined dark saddle blotches on body and caudal fin; dorsal and caudal fins without black tips; mouth lining light. Monospondylous precaudal centra 33 to 36. Size moderate, adults up to about 66 cm.
Western North Pacific: Southeastern Honshu, Japan.
Habitat and Biology:
A common, probably deepwater bottom shark of Japan. Oviparous, possibly with a single egg laid per oviduct. 3 There is an interesting sexual dimorphism in adults of this shark, the anal fins of males being about 2% of total length shorter than females, which 2 was thought by Nakaya (1975) to be related to the function of the unusually long claspers of this shark, which presumably need more 1 clearance of the anal fin than such species as G. eastmani and G. sauteri, which have much shorter claspers and lack the sexual dimorphism in anal length.
Adults maturing at about 53 to 55 cm; largest reported 65.6 cm.
Interest to Fisheries:
Holotype: Hokkaido University Laboratory of Marine Zoology, HUMZ 40012, 596 mm adult male. Type Locality: Mimase, Kochi Prefecture, Honshu, Japan.