Takeda & Kurata, 1984
Description of holotype: Breadth and length of carapace, 8.2 and 6.2 mm, respectively. Carapace quadrilateral, and about three-fourths as wide as long. Its dorsal surface markedly flattened laterally and posteriorly, weakly declivous anteriorly, being ill-defined and sparsely covered with short stiff setae and soft shaggy hairs; anterior part in front of gastric region traversed by six raised, nude areolets, which are symmetrically arranged at each side; the innermost is somewhat heart-shaped, and the median is similar, but smaller and proportionally wider; the outermost is oblique along antero-lateral border of carapace. Front cut into two lobes by a median wide notch; each lobe most strongly developed near frontal median notch, being very weakly concave near supraorbital angle, which is obtuse; supraorbital border transverse for its most part, having a small, but distinct notch at the middle.
Supraorbital angle more or less produced, but obtuse, being followed by three tuberculated antero-lateral teeth; first two nearly equal to each other in size and shape, and the last similar to the preceedings in shape, but about half in size. Postero-lateral border slightly longer than the antero-lateral, and only weakly convergent; about anterior third just behind last antero-lateral tooth is callous and obtusely ridged.
Chelipeds covered with shaggy, rather stiff setae of variable lengths; distal margin of merus thickened at its upper part; carpus ornamented with a longitudinal callous ridge on its upper surface, its outer margin being also callous; surfaces of palm and fingers granulated; fingers darkened for less than distal halves.
Ambulatory legs of right side missing. Ambulatory legs slender, first three pairs attaining one and a half times as wide as carapace; each segment covered with stiff setae on both borders; in first three pairs distal margin of each merus tather thickened, and upper surface of carpus raised, with a longitudinal furrow along anterior border. (Takeda & Kurata, 1984)
Type locality: Takinoura Bay, Ani-jima, Ogasawara-shoto, Japan.
Range: Japan - Tanegashima and Ogasawara-shoto (Takeda & Kurata, 1984), Tanegashima, Ogasawara-shoto, west coast of Kii Peninsula and Ie-jima, Ryukyu-shoto (Takeda & Marumura, 1995b).