Sakai, 1938
A fragmentary specimen, the thoracic legs and abdomen being missing, but clearly different from any of its congeners, so that I regard it as new to science.
The general outline of carapace resembles that of Xenocarcinus nakazawai, but the tuberculation on the dorsal surface is more remarkable: the gastric region markedly convex and mounted with six vestigial granules, which are covered with hairs; the cardiac region is mounted with a pair of tubercles, each of which is again divided into two or three indistinct tubercles; the posterior margin of carapace is armed with two similar prominent tubercles one on either side; the hepatic region unarmed; the branchial region with two transversely approximated tubercles near the middle of the lateral border, the outer one being somewhat larger and projecting beyond the outline of the carapace; the postero-lateral border has an indistinct tubercle in the middle.
The pseudorostrum is beak-shaped, its proximal portion is much thicker and stouter than in any other species of this genus, but its distal portion rapidly tapers and forms a slender median style, which projects from a lower plane and is, unlike that of the other species, not at all bifurcated. As in the other species, the entire surface of pseudorostrum is covered with curled hairs.
The intercalated lobe, which occurs between the supraocular eave and the postocular cup, is well defined. (Sakai, 1938)
Type locality: Misaki, Sagami Bay, Japan.
Range: Japan - Misaki (Sakai, 1938a), Misaki and Osaka Bay (Sakai, 1976a).