Dana, 1852
Antennal flagellum excluded from orbital hiatus; posterior border of cephalothorax curved, forming curved postero-lateral junction; 6 antero-lateral teeth, first antero-lateral tooth truncate; no distinct cardiac ridges on carapace; anterior border of arm of cheliped with 3 or more spines; 5 spines on hand of cheliped, including 2 small distal spines; hand of cheliped swollen; penultimate segment of male abdomen with sides parallel for most of their length. (Davie 1999)
Carapace tomentose, about 1.5 times as broad as long, with the usual transverse ridges on front, gastric and epibranchial regions, posterior half of the surface behind the epibranchial region without a ridge. Front cut into 6 teeth, the middle two more prominent. Dorsal margin of orbit granuled, with 2 fissures, its inner end acuminate. Antero-lateral margin divided into 6 teeth: the first truncate, slightly incurved; the second to fifth gradually increasing in size; the last one smaller, spiniform and projecting sideways. Third maxillipeds with surface smooth and marked with punctation, merus with its outer-distal angle slightly produced laterally.
Chelipeds smooth. Merus with 3 teeth on the anterior margin, and distributed with microscopic granules on posterior margin. Carpus with a stout spine at inner angle, 3 spinules on the outer surface. Palm thick, outer surface marked with 3 smooth ridges, the same as the inner surface. Dorsal surface with 2 ridges and 5 spines (including the basal one), distal one with 2 smaller spines. Fingers slightly longer than palm, with strong teeth on the inner margin, tips crossing when closed. Natatory legs with merus about 1.5 times as long as broad, bearing a stout spine at the postero-distal end.
First pleopod of the male with distal portion relatively stout; tip spoon-shaped and armed with bristles on both the outer and the inner side. Male abdomen triangular, third to fifth segments fused, the sixth segment broader than long, its lateral margin subparallel, the seventh one subtriangular. Carapace length of the male 36.6 mm, breadth 36 mm. (Dai & Yang, 1991)
Type locality: Singapore.
Range: India - Orissa coast (Alcock, 1899a); Burma - Akyab (Alcock, 1899a); Mergui Archipelago (Alcock, 1899a); China - Tsimei and Xiamen (Shen, 1940b), Guangxi and Guangdong (Dai & Yang, 1991), Zhujiang estuary (Chu et al., 1996); Taiwan - Yüan-lin Province, Chia-i Province, and Kaohsiung Province (Huang & Yu, 1997); Thailand; Malaysia - Terengganu (Lanchester, 1902); Singapore (Dana, 1852, Shen, 1937); Indonesia - Deli, Sumatra (Leene, 1938).