Stimpson, 1858
A small species, the extreme length of carapace being less than 12 mm., even in a full-grown specimen. The upper surface of carapace is thickly covered with sharp spinules. There are ten marginal and one intestinal spine, which are distinctly larger than the spinules found on the upper surface, having similar arrangement to those of Arcania undecimspinosa. The front is strongly produced and is bidentate, the tip of the denticle being spiniform. The lower surface of the carapace is covered with fine granules but with no spinules.
Chelipeds are somewhat stout, arm is thickly covered with miliary granules and a few spinules on the posterior border; wrist and palm are also microscopically granulated. Fingers are subequal to the palm in length and are slightly compressed. Meri of the ambulatory legs are spinulated along the anterior border, the following segments are all smooth and slender. (Sakai, 1937)
Type locality: coast of China, near Hong Kong.
Range: Japan - Maizuru (Ortmann, 1892), Suruga Bay, Tanabe, between Shimonoseki and Tsushima, and Nagato (Yokoya, 1933), Shimoda (Sakai, 1935), Sagami Bay, Shimoda, Ise Bay, Nanki Shirahama and Nagasaki (Sakai, 1937a), Amakusa, Sea of Ariake and Niigata (Miyake et al., 1962), Sagami Bay (Sakai, 1965b), Tsushima Strait (Takeda, 1973c), Sagami Bay, Mikawa Bay, Kii Minabe and Tosa Bay (Sakai, 1976a), Amakusa (Yamaguchi et al., 1976), Shiono-misaki (Takeda, 1979a), Manazuru, Mikawa Isshiki, Tsuyazaki and Amakusa (Muraoka, 1998), off Matsuyama, Seto Inland Sea (Takeda et al., 2000); East China Sea (Takeda & Miyake, 1970a); Korea - north of Cheju-do (Miers, 1879b), Deugryang Bay (Kim, 1973); China - coast of China, near Hong Kong (Stimpson, 1858c, 1907), Jiaozhou Bay (Shen, 1937), near Hong Kong (Stimpson, 1858c); 30-100 m.