(de Haan, 1833)
Carapace rounded subquadrate, slightly broader than long, densely covered with tomentum, regions well defined. Anterior and lateral part of its surface with rounded tubercles. Front broad, deflected, bilobed, each lobe with 2 acute teeth, separated from the innerorbital tooth by a U-shaped notch, the latter with 2 accessory blunt teeth. Epistome with 2 triangular teeth at the middle, alternately followed by 4 small teeth, then a slightly larger tooth; between the larger tooth and the outermost 2 large triangular teeth there is a small tooth. Antero-lateral margin with 4 teeth including the outerorbital tooth, regularly decreasing in size.
Chelipeds short. Carpus with granular ridges on its dorsal surface, the inner-distal angle blunt. Palm with 6 granular ridges on its dorsal and outer surface, with hairy grooves between the ridges, the inner and ventral surfaces granulated. Fingers spoon-shaped at the tips, inner borders bluntly toothed. Ambulatory legs stout; merus with 5-7 acute teeth on its anterior border; carpus and propodus with rows of tomentum; dactylus with 2 rows of acute teeth on its ventral surface.
First pleopod of the male stout, compressedly trigonal, with distal elliptical concave orifice, closely covered with long and short stiff setae. Abdomen triangular; the third to sixth segments fused; telson with basal margin broader than long. Abdomen rounded and large, 7-segmented. Carapace length of the male 33 mm, breadth 39 mm; of the female, length 50 mm, breadth 57 mm. (Dai & Yang, 1991)
Type locality: Japan.
Range: Japan - (de Haan, 1833), Tokyo Bay and Katsuyama (Ortmann, 1894a), Shimoda (Stimpson, 1907, Sakai, 1935), Iwate Prefecture, Boshu, Tokyo Bay, Sagami Bay, Izu Peninsula, Suruga Bay, Ise Bay, Kii Peninsula, Tosa Bay, Miyazaki Prefecture, Kagoshima and Nagasaki (Sakai, 1939), Hachijo-jima (Sakai, 1954), Sagami Bay (Sakai, 1965b), from Iwate Prefecture southward to Kyushu and Okinawa (Sakai, 1976a), Amakusa (Yamaguchi et al., 1976), Nezumigaseki, Yamagata Prefecture (Suzuki S., 1979), Kushimoto (Miyake, 1983); Vladivostok; Korea - Seogwipo, Seongsanpo, and Gapa Island (Kim, 1973), Sogwipo (Kim & Chang, 1985); Taiwan - (Sakai, 1939, Dai & Yang, 1991), Chi-lung (Lin, 1949); Bismarck Islands; Norfolk Island; Kermadec Islands - Sunday Island (Chilton, 1911); 10-15 m.