Balss, 1922
Carapace hexagonal in general outline and its dorsal surface naked on the anterior half but tomentose on the postero-lateral, cardiac and intestinal regions; the naked surface is very thickly covered with a pavement of vesiculous granules. The formation of regions of carapace is peculiar, i.e., 1M, 2M and 2L, 3L are all continuous with one another, extending from the third antero-lateral tooth to the upper frontal surface; 4L, 5L are somewhat defined but other lobules are ill-defined. Front extremely deflexed, each lobe being extremely convex near the median notch but wanting the customary lateral lobule. The four antero-lateral teeth are granulated, the last of which is smallest but long and the penultimate one largest. The postero-lateral borders are very markedly concave.
The wrist has two elongate depressions disposed obliquely on outer surface, and one on upper surface along the superior ridge which bears several sharp tubercles. Palm bears about four teeth on the superior ridge and has a broad, longitudinal depression which is broken near the middle, along the upper outer surface; the depression is bounded by two longitudinal ridges, which meet at the distal end of the segment. The lower half of the palm is beaded with sharp granules of good size. Ambulatory legs are very slender. The seventh segment of male abdomen is extremely elongate. (T. Sakai, 1939: 530)
Type locality: Sagami Bay, Japan, 150 m.
Range: Japan - Sagami Bay (Balss, 1922c, Sakai, 1939), Sagami Bay and Tosa Bay (Sakai, 1965b), Bungo Strait, Tosa Bay, Munakata-Oshima, Fukuoka Pref., Amakusa-shoto, Nagasaki and Ibaragi Pref. (Takeda & Miyake, 1969c), north off Tsushima (Takeda, 1973c), Sagami Bay, Manazuru, Kii Minabe, and Tosa Bay (Sakai, 1976a), Ogasawara-shoto (Takeda, 1977a), Kii Nagashima (Miyake, 1983).