(Forskål, 1775)
Carapace convex, smooth; regions ill defined; orbital, hepatic, and branchial regions marked with fine net-like corrugation. Front deflected downwards, its anterior margin straight in dorsal view, bearing a lobate process in the middle. Distance between inner superorbital teeth about one-third as long as breadth of carapace. Dorsal margin of orbit slightly convex and with a gradually postero-lateral slant. Antero-lateral margin longer than postero-lateral margin, strongly arched; postero-lateral margins converging backwards. Conjunctive site between antero-lateral and postero-lateral margins provided with a blunt tooth.
Chelipeds stout, asymmetrical. Carpus with inner-distal angle obtuse. Major chelipeds with massive palm, fingers each with an obtuse tooth at subproximal end of the inner margins. Minor chelipeds relatively smaller and thinner; finger with no distinct tooth. Ambulatory legs smooth, the border bluntly round; dactyli elongate and slender, with a dark brown cuticular claw at tip.
First pleopod of the male with distal portion slightly curved inner-dorsally; tip obliquely truncated, with distinct aperture. Male abdomen narrow and elongate, third to fourth segments fused; sixth segment much broader than long; the terminal segment triangular. Female abdomen oblong, terminal segment acutely triangular. Carapace length of the male 41-56 mm, breadth 55-78 mm; of the female, length 49.1 mm, breadth 68.2 mm. (Dai & Yang, 1991)
Type locality: Red Sea.
Range: Red Sea (Klunzinger, 1913); Kenya - Jadini; Zanzibar (Lenz, 1905); Mozambique - Delagoa Bay (Barnard, 1950); South Africa - Durban (Barnard, 1950); Madagascar - Nosy Bé and Fort-Dauphin; Iles Glorieuses; Aldabra Islands; Seychelles - Amirante and Coëtivy Islands (Rathbun, 1911); Mauritius (Bouvier, 1915b, Michel, 1964); Persian Gulf - Arabi (Stephensen, 1945); Andaman Islands (Alcock, 1898); Nicobar Islands (Alcock, 1898); Japan - Okinawa (Stimpson, 1907), Tosa Bay and Northern Daito-jima (Sakai, 1939), Hachijo-jima (Sakai, 1954), Kii Nagashima, Kii Minabe, Amami-Oshima, Yoron-jima and Ishigaki-jima (Sakai, 1976a), Okinawa-jima (Miyake, 1983), Wagu, Kii Nagashima, Kii Minabe, Kushimoto, Amami-Oshima, and Yoron-jima (Muraoka, 1998), Ginowan, Okinawa (Shokita et al., 2000), Sagami Bay, Ogasawara-shoto; Taiwan (Lin, 1949); China - Hainan Island and Paracel Islands (Dai & Yang, 1991); Indonesia - Ambon (de Man, 1887d, Rathbun, 1910b), west of Celebes; Palau (Sendler, 1923, Takeda, 1976a); New Caledonia - Ilot Maitre (Takeda & Nunomura, 1976); Fiji (Dana, 1852); Hawaii - Sandwich Island (Dana, 1852), Honolulu, Waikiki Beach, Hilo, and Waiawa Kanai (Rathbun, 1906); Line Islands - Palmyra and Tabuaeran (Edmondson, 1923); Tahiti (Stimpson, 1907, Guinot, 1968c); Tubuai Islands - Rurutu (Poupin, 1996a).