(Stimpson, 1858)
Carapace roundly squarish, slightly broader than long. Surface convex in the anterior half and depressed in the posterior half; each region with naked tubercles; a pair of oblong tubercles on postfrontal region, a pair of crescent-like elevations each on either side to the mesogastric region, a transversely band-like elevation on the cardiac, another near the intestinal region; hepatic region also with an oblong elevation; depressions covered with pubescence. Frontal margin slightly produced and deflected, cut into 2 lobes by a shallow notch. Orbit large, eye-peduncle furnished with pubescence of varying length on the dorsal surface, dorsal margin covered with a coat of down, outerorbital angle triangular. Flagellum of the antenna slender and elongate. Merus of the third maxilliped squarish, with the outer-distal angle produced. Antero-lateral margin with 2 triangular teeth; junction of the antero-lateral and postero-lateral margins armed with 2 naked processes fused together; postero-lateral margins nearly parallel.
Chelipeds symmetrical and massive; surface covered with down and long hairs. Merus armed with 4 naked projections on its outer surface, the last two large and transversely placed. Carpus inflated, with 4 naked processes. Palm densely furnished with down and covered with beaded granules in denudation. Fingers stout, without gaping. First to third ambulatory legs slender and elongate, merus, carpus and propodus with smooth; obtuse longitudinal carina on the dorsal surface; dactylus with a claw-like distal end.
First pleopod of the male more or less S-shaped, apex acutely hook-shaped and subextremity armed with spinules of various lengths. Male abdomen 7-segmented; telson with distal margin bluntly round and longer than the sixth segment. Carapace length of the male 8.3 mm, breadth 9.8 mm. (Dai & Yang, 1991)
Type locality: Amami-Oshima, Japan.
Range: Japan - Amami-Oshima (Stimpson, 1858b, 1907), Ishigaki-jima (Takeda, 1977d); China - Hainan Island (Dai & Yang, 1991).