White, 1852
The carapace is extremely broadened anteriorly and the dorsal surface traversed by three transverse ridges, by which the surface is divided into three faces of almost equal length; the anterior ridge is most prominent. The front is narrow and constricted between the bases of the eyestalks but broadened distally, the free margin deflexed and medially sinuate. The upper orbital borders are weakly arched and markedly oblique, the external orbital angle is very prominent and projecting obliquely backwards. The lateral borders behind the external orbital angles are unarmed and markedly convergent backwards. The posterior border is almost straight. The eyestalks are very slender and long, being nearly half the distance between external orbital angles, the cornea only slightly swollen.
Chelipeds are slightly asymmetrical, the merus is obtusely prismatic and thickened distally; the wrist is very short and roundish, its inner angle is armed with a spinule; the palm is weakly compressed and distally broadened, the length subequal to the arm; the fingers of minor cheliped sharply denticulated on whole prehensile edge, those of major cheliped widely gaping in proximal half and their distal half only denticulated, the movable finger having a stout tooth near the base.
All pairs of ambulatory legs are not much unequal in shape and length; the meri are broadened in the middle portion and are armed with a spinule near the distal end of the anterior border; carpus and propodus are sparingly hairy along the anterior border. The male abdomen nearly triangular in general outline. (T. Sakai, 1939: 564)
Type locality: Port Curtis, Australia.
Range: Japan - Kii Strait and Koshiki-jima (Yokoya, 1933), Hayama and Nagasaki (Sakai, 1939), Sagami Bay (Sakai, 1965b), Sagami Bay, Kii Nagashima, Kii Minabe, Nagasaki, Yonago, and Noto Peninsula (Sakai, 1976a), Tanabe Bay (Miyake, 1983); China - Hainan Island (Dai & Yang, 1991); Philippines - north of Lubang Island (Serène & Vadon, 1981); Australia - Port Curtis (White, 1852), Moreton Bay (Griffin & Campbell, 1969); New Zealand - (Takeda & Miyake, 1969b), Queen Charlotte Sound near Long Island (Miers, 1886); 35-150 m.