Carapace convex, 1.3 wide as long, shallow longitudinal groove separating gastro-cardiac from branchial regions, hepatic region depressed. Carapace surface tuberculate, branchial tubercles largest, intestinal, metabranchial regions with minutely beaded transverse lines, increasing in length laterally. Front quadridentate, two median teeth projecting. Basal antennal article granulate, anterior margin concave, proximal lobe dilate, peduncle emerging from distal angle. Afferent branchial channel ending below orbit in granulate tridentate process. Endostomial septum visible with first maxillipeds closed, with straight anterior margin. Distal margin of first maxillipeds with triangular notch. Antero-lateral margin arcuate, carinate, unevenly granulate anteriorly, anterior tooth prominent, with six triangulate teeth posteriorly. Postero-lateral margin setose, beaded, three anterior teeth triangulate, growing in size posteriorly, three posterior teeth shallow, with beaded median ridges. Posterior margin sinuous, beaded. Merus of cheliped distally with setose, quadrilobate lamina. External surface of chela inferiorly granulose, obliquely traversed by three rows of minutely granulate tubercles, largest tubercles just below crest. Crest of larger chela cut into seven teeth increasing in size distally, proximalmost bicuspidate. Lower margin closely beaded from proximal lamellar tooth to pollex. (Galil, 1997a)
Type locality: Kii Peninsula, Japan.
Range: Japan - Kii Peninsula and E. of Muroto-misaki (Galil, 1997a).