Sakai, 1969
Description of female: The entire animal is soft, as in the usual species of the genus Pinnotheres. The colouration in the living stage is light lemonish white. The carapace is very broad and transversely elliptical and anteriorly convergent; the ratio between length and breadth is 1 : 1.5. The dorsal surface is evenly convex and smooth; the front is declivous, its margin being slightly bilobate. The antero-lateral borders are markedly divergent backwards; the posterior margin is very broad, a little convex in the middle.
The dactylus of the external maxillipeds is very small and slightly curved inward near the tip, inserted at the end of the propodus.
The chelipeds are stout and longer than any of the ambulatory legs; the propodus is distally thickened and the dactylus armed with a tooth near the proximal end of the prehensile edge. The movable finger is unarmed.
The anterior three pairs of ambulatory legs are subequal in length; the last pair is slightly more slender and shorter than the preceeding ones. The dactylus of all pairs is uniformly short and hooked at the tip.
Description of male: The male is always living with the female in the stomach of the same host. The entire body is fairly well calcified. The carapace is narrower than in the female, rounded quadrangular in outline. The ratio between length and breadth is approximately 1 : 1. The front protrudes well beyond the level of the eyes, its margin being obtuse and obscurely bilobate.
The chelipeds are robust and the propodus distally thickened; the movable finger is strikingly curved inward at the tip and armed with a tooth near the proximal portion of the prehensile edge. The movable finger is unarmed. The features of the ambulatory legs are almost the same as in the female. In the male of Pinnotheres, the ambulatory legs are usually haired along the anterior and posterior borders of the carpus, propodus and dactylus, but in the present case, all such segments are naked. (Sakai, 1976)
Type locality: Yoron-jima, Amami-shoto, Japan.
Range: Japan - Yoron-jima (Sakai, 1976a); Palau (Takeda & Shimazaki, 1974).