(Stimpson, 1858)
Carapace wider than long, its dorsal surface usually without ridges, but in some specimens a faint gastro-cardiac groove may be present; rostrum truncated, rostral keel deep, discontinuous with interantennular septum. External maxilliped often with a well defined longitudinal ridge on merus extending to ischium. Chelipeds heavier than subsequent ambulatory legs. Second to fifth pereiopods with terminal spine on carpus subequal with terminal spine on merus; dactyli with two subterminal teeth. Male abdomen consisting of five pieces, segments III and IV fused. (Türkay 1995)
Type locality: Amami-Oshima and Okinawa, Japan.
Range: Zanzibar (Lenz, 1905); India; Sri Lanka; Andaman Islands - Port Blair (Chopra & Das, 1930); Nicobar Islands (Alcock, 1900b); Japan - Amami-Oshima and Okinawa (Stimpson, 1858b, 1907), Shimoda (Sakai, 1935), Suno-saki, Shimoda, Ise Bay and Nagasaki (Sakai, 1938a), Hachijo-jima (Sakai, 1954), Sagami Bay (Sakai, 1965b), Suno-saki, Sagami Bay, Shimoda, Ise Bay, Nagasaki, Fukui Prefecture, and Iriomote-jima (Sakai, 1976a), Nezumigaseki, Yamagata Prefecture (Suzuki S., 1979), Kushimoto (Miyake, 1983); Korea - Cheju-do (Kim & Chang, 1985); Taiwan - Taipei area (Ng & Chuang, 1996, Ng & Jeng, 1999); ?Indonesia - east of Seram and Ambon (Tesch, 1918a); Australia - Port Denison, Holbourne Island, High Island Reef, Flinders Island, and Low Isles, Queensland (Lucas, 1980); New Caledonia (Takeda & Nunomura, 1976, Lucas, 1980); Loyalty Islands (Lucas, 1980).