Sakai, 1939
Description of the female holotype: The carapace rounded quadrangular, the front extremely deflexed and straight, the lateral borders somewhat concave, the posterior border almost straight. The dorsal surface is markedly convex in the middle; there is a very short and subparallel indistinct groove on either side of the front, each extending from the upper orbital border toward the dorsal surface of the carapace. The ischium-merus joint of the external maxilliped is moderately broad and its inner angle rounded; the carpus is short but the propodus is more than twice as long as the carpus, and is insensibly broadened distally and the distal margin is subtruncate and slanting inwards.
Chelipeds are not much stouter than the ambulatory legs, the immovable finger bears two denticles near the base, the movable finger has a tooth, which fits in the gape between the two denticles of the former; the distal end of the immovable finger is longitudinally hollowed. All pairs of ambulatory legs are naked and not much unequal in thickness; the second pair is much the longest, the first and third pairs are a little shorter and subequal; the last pair is insensibly the shortest.
This species closely resembles Pinnotheres subglobosa Baker (cf. Rathbun 1923, p. 96, pl. 16, fig. 1 and text-fig. 1) from Australia, but the propodus of the external maxilliped of that species is shorter and much broadened distally than in the present species; the dactylus of the second ambulatory legs of that species is relatively longer than that in the present species. (T. Sakai, 1939: 596)
Type locality: Momotori, Ise Bay, Japan.
Range: Japan - Ise Bay (Sakai, 1933b, 1939), Sagami Bay and Onomichi (Sakai, 1965b), Sagami Bay, Ise Bay and Onomichi (Sakai, 1976a).