(Rathbun, 1907)
Carapace with short sparsely arranged hairs underlaid by small granules; frontal and 3 pairs of gastric ridges present, epibranchial ridge interrupted medially, cardiac ridge represented by 2 very small broadly separated indistinct crests and mesobranchial ridges markedly prominent; front with 2 broad lobes separated by a distinct notch; 5 antero-lateral teeth, fourth shortest, fifth the sharpest and the most protruding. Basal antennal joint with an elevated crest surmounted by rounded granules. Upper surface of cheliped palm with 2 anterior and 2 posterior spines; inner face usually smooth and polished, sometimes with traces of squamiform markings. Posterior border of propodus of swimming leg with 4-6 spines. Male first pleopod relatively stout, curving smoothly and evenly to the slightly flared, strongly recurved tip; inner surface with 3-9 stout recurved terminal bristles; outer surface with 3-5 stout bristles. (Türkay 1995)
Front 2-lobed, not very protruding, median frontal notch relatively well developed, front not forming a single smooth curve; basal antennal joint with acute granular or tubercular crest; 5 antero-lateral teeth; cardiac ridges may be present on carapace; mesobranchial ridges anterior to cardiac ridges; protogastric region smooth or granular but without ridge; tips of chelipeds pointed, not spoon-shaped, hand of cheliped without squamiform markings; male first pleopod with recurved tip, most of subterminal spines on concave surface; male abdomen with side of penultimate segment with marked distal convergence. (Davie 1999)
Type locality: Truk, Caroline Islands.
Range: Madagascar - baie d'Ambaro and Toliara (Crosnier, 1962); Sumatra - Poeloe Weh (Stephenson, 1975); Japan - Shimoda, Gobo and Tosa Bay (Sakai, 1939), Izu Peninsula, Kii Peninsula, Tosa Bay, and Yaeyama-retto (Sakai, 1976a), Shiono-misaki (Takeda, 1979a), Oshima Passage, Amami-Oshima (Takeda, 1989); Philippines; Caroline Islands (Rathbun, 1907); Marshall Islands - Bikini (Stephenson, 1976); Australia - Shark Bay, Maud Landing and Flat I. near Onslow (Stephenson, 1961), Wallis Lake, New South Wales (Stephenson & Rees, 1968); 10-45 m.