(Latreille, 1825)
The carapace typically pyriform, the regions are well defined by deepish grooves; the entire dorsal surface is closely covered with granules and tubercles of various sizes, of which nine gastric, three cardiac, and one intestinal are somewhat larger. Of the branchial tubercles, three along the lateral margin, two on mesobranchial and one on metabranchial region are larger and somewhat erect. The pseudorostral spines are obliquely deflexed and in closest contact throughout their whole length, the tips only being slightly divergent. The preocular spine is very prominent and erect, although it is not at all acuminate. The orbits are tubular and laterally projecting beyond the general outline of the carapace. The curved supraocular eave, the prominent postocular cup and the dilated outer border of the basal segment of antenna are in close contact with one another and circumscribe the eye-peduncle.
The movable peduncular segments of antenna are flattish and fringed with long hairs on both sides; the following flagellum very small. There are two or three pterygostomial tubercles, which are very prominent. The antero-external angle of the external maxillipeds is noticeably expanded.
Chelipeds of male are very stout; arm and wrist are covered with tubercles, while the palm is smooth and glabrous and is slightly inflated on the inner surface, its upper and lower borders being rounded. Fingers gape widely at base, only their distal one fourth being in contact with each other. The fingers of male gape widely at the base, the movable finger is armed with a stout tooth near the base. The merus of the ambulatory legs is tuberculated, the tubercles being mainly arranged along the anterior and posterior borders; carpus is compressed and distally broadened and dorsally channelled, its outer and inner borders tuberculated. Dactylus is sensibly curved at tip.
Abdomen of both sexes consists of seven distinct segments. (Sakai, 1938: 318)
Type locality: unknown.
Range: Andaman Islands (Alcock, 1895a); Nicobar Islands; Japan - Okinawa and Amami-Oshima (Stimpson, 1907), Shimoda (Sakai, 1935), Tateyama Bay, Misaki, Shimoda, Nanki Shirahama and Nagasaki (Sakai, 1938a), Hachijo-jima (Sakai, 1954), Sagami Bay (Sakai, 1965b), Tokyo Bay, Sagami Bay, Shimoda, Wagu, Kii Nagashima, Kii Minabe, Kushimoto, Amami-Oshima and Yoron-jima (Sakai, 1976a), Nanki Shirahama (Miyake, 1983), Misaki and Nagasaki (Griffin & Tranter, 1986a), Hayama, Manazuru, Shimoda, Kii Minabe, Kushimoto, Kochi City, Tosashimizu, and Yoron-jima (Muraoka, 1998); Taiwan; Singapore; Philippines - Tara Island, Batan Island, Tagbilaran Strait, Camiguin Island and Pilas Island (Griffin, 1976), Tubajon Bay and Zamboanga (Griffin & Tranter, 1986a); Sulu Archipelago - Tawitawi Group (Griffin, 1976), Tawitawi Group and Siasi Island (Griffin & Tranter, 1986a); Palau (Takeda 1973); Indonesia - Salibabu Island, Selat Sape, Borneo Bank, Sula Besi, Kajoa Island, Gomumu Island, Banda Sea, Ambon, between Nusa Besi and north-east point of Timor, Timor, Roti Island, Tanimbar, Kepulauan Kai, Manokwari, north of Jayapura and Biak, Irian Jaya (Griffin & Tranter, 1986a); Australia - Port Darwin and Woodlark Islands (Haswell, 1880b).