(Fabricius, 1798)
Monotypic genus, genus definition repeated:
Carapace broadened anteriorly, regularly convex from side to side, no median dorsal carina, a transverse ridge of spinules between antero-lateral spines, surface otherwise smooth; fronto-orbital border less than half the greatest width of carapace; five fronto-orbital spines; antero-lateral borders with one spine. Eye peduncle folding obliquely backward and downward. Dorsal border of cheliped palm without spines. Fifth pereiopod, compared to the preceeding ones, slightly reduced in size. (Türkay 1995)
Type locality: unknown.
Range: Red Sea; Zanzibar; Mauritius: India - coast of Malabar (Alcock, 1896); Andaman Islands (Alcock, 1896); Japan - (de Haan, 1841), west of Tanegashima (Yokoya, 1933), Shimoda (Sakai, 1935a), Shimoda, Nanki Shirahama and Nagasaki (Sakai, 1937a), Amakusa (Miyake et al., 1962), Sagami Bay (Sakai, 1965b), Sagami Bay, Shimoda, Kii Nagashima, Kii Minabe, and Tosa Bay (Sakai, 1976a), Mikawa Isshiki, Nanki Shirahama and Tosa Bay (Muraoka, 1998); Taiwan; Sulu Sea (Ihle, 1918); Indonesia - Kuandang Bay and Banda (Ihle, 1918); Australia - Angel Island, Dampier Archipelago, and between Point Sampson and Onslow (Tyndale-Biscoe & George, 1962).