Stimpson, 1858
Carapace rounded quadrangular, broadened anteriorly and its dorsal surface flattish and sparingly tomentose toward the lateral and postero-lateral surfaces. The front a little broader than one-third the extreme width of carapace, the middle portion feebly concave. The lateral borders are entire, bordered by a ridge of microscopic granules. Chelipeds are symmetrical; the palm is lined with fine granules along the inner border, the palm is inflated, having several granules in a group in the middle of the inner surface; the chela has a patch of soft hairs near the base of the outer surface. The second and third pairs of ambulatory legs are subequal in length, the first pair a little shorter and the last pair smallest; each segment is fringed with short setae mainly along anterior and posterior borders. (T. Sakai, 1939: 662)
Type locality: Amami-Oshima, Japan.
Range: Japan - Amami-Oshima (Stimpson, 1858b, 1907), Shimoda (Sakai, 1935), Ajiro, Shimoda, Nagasaki and Kagoshima (Sakai, 1939), Hachijo-jima (Sakai, 1954), Sagami Bay (Sakai, 1965b), Oga Peninsula, Boso Peninsula, Tokyo Bay, Sagami Bay, southwards to coast of Kyushu and also coast of Sea of Japan (Sakai, 1976a), Amakusa (Yamaguchi et al., 1976), Yamagata Prefecture (Suzuki S., 1979), Nanki Shirahama (Miyake, 1983); Korea - Ulreung Island, Geoje island, Tong-yeong, and Cheju-do (Kamita, 1941), Cheonbu, Hyangnam Dong, Bangjugpo, Jeju, and Iho Ri (Kim, 1973), Cheju-do (Kim & Chang, 1985); Taiwan; coasts of pebbles, near high tidal mark.