(von Siebold, 1824)
Carapace convex, moderately sculptured, slightly broader than long; branchial and branchio-cardiac grooves very distinct, cervical groove distinct but less deep; exorbital tooth well developed, slender or blunt, shorter than front. Chelipeds equal in size and shape in young males and females, but in adult male right chela greatly inflated. Second and third legs very slender and long, each of them reaching beyond front with distal end of merus; merus of third pereiopod less than 6.3 times as long as high. (Türkay 1995)
Type locality: Shimonoseki, Japan.
Range: Japan - (von Siebold, 1824, 1826, de Haan, 1841, Herklots, 1861, Ives, 1891, de Man, 1896b, Parisi, 1914, Sakai, 1936b, 1940, 1956, 1980, 1985, Imajima et al., 1970, Nishimura & Suzuki, 1971, Odawara, 1973, Takeda, 1975b, 1982, 1983, Miyake, 1983), Shimonoseki (von Siebold, 1824, Nees von Esenbeck, 1825), Nagasaki (de Haan, 1841), Kobe (Miers, 1886), Wakanoura (Rathbun, 1902a), Ishikawa Prefecture (Anonymous, 1904, Sakai, 1940), Hakodate Bay (Stimpson, 1907), Okayama and Osaka Bay (Balss, 1922b), Kii Peninsula, Koshiki-jima and Shibushi, Osumi (Urita, 1926a), east of Owase (Yokoya, 1933), Nagasaki (Sakai, 1934a), Onomichi, Yashima, Tosa Bay, and Nagasaki (Sakai, 1937a), Osaka Bay (Urita, 1942), Shimabara Peninsula, Sea of Ariake and Amakusa (Miyake, 1961), Amakusa (Miyake et al., 1962, Takeda, 1978a, Yamaguchi et al., 1987), San-in District (Kamita, 1963), Nagasaki (Serène & Romimohtarto, 1969, Sakai & Holthuis, 1970, Yang C.M., 1979), Onomichi, Hizen-hama, Yashima, Shimabara Peninsula (Sakai, 1976a), Aitsu (Yamaguchi et al., 1976), Ise Bay (Morita, 1977), Sea of Ariake (Sagano, 1981), estuary of Ohi-gawa (Takeda, 1981), east of Owase (Horikoshi et al., 1982), Tanabe Bay (Miyake, 1983), Tokushima Prefecture (Sakai K. & Nakano, 1983), Kobe, Sakanoura and Kagoshima (Holthuis & Manning, 1990); Korea - Yellow Sea (Kamita, 1934, 1936a), Korea Strait (Kamita, 1936a), Jinsen (Urita, 1926a), Zinsen (Sakai, 1937a), Wido Island (Kim, 1970, 1973), Busan, Jinhae, Masan, Asan, Juan, Hancheon, Nanseo, Myeon, and Suun Island (Kamita, 1941b); China - (Yang S., 1986, Chen H., 1986b), Ningbo (Fauvel, 1880), Liaodong Province (Zhou & Sun, 1986), Yen t'ing, Fuzhou, Jimei and Xiamen (Rathbun, 1931), Liaodong Bay, Bo Hai Gulf, Shandong Peninsula (Shen, 1932), North China and Bo Hai Gulf (Shen, 1937), Haimen, Ningbo, Yen t'ing, Fuzhou, Jimei, and Xiamen (Shen, 1940b), China Seas (Shen & Liu, 1963), Beitang, Tanggu, Bo Hai Gulf, Shanghai, Zhejiang Province, Yent'ing, Fuzhou, Jimei, Xiamen, and Nan'ao Island (Holthuis & Manning, 1990), Paracel Islands (Dawydoff, 1952); Hong Kong (Shen, 1931a, 1940, Holthuis & Manning, 1990); Taiwan - An-ping (Maki & Tsuchiya, 1923), Chilung (Serène & Romimohtarto, 1969, Yang C.M., 1979, Holthuis & Manning, 1990), Hsiak'unhsen and Tingsh'ieting (Lin, 1949); Vietnam - Gulf of Tonkin (Dai & Song, 1986), Nha Trang Bay (Serène & Romimohtarto, 1969, Yang C.M., 1979).