(Walker, 1887)
With the exception of crosnieri in which the teeth are not well differentiated, the antero-lateral margins of the carapace have three or four teeth behind the exorbital angle, the two posterior are generally more projecting and more angular. The carapace width is greater than 1.30 times the length. The carapace has the regions 2M and 3M entirely separated from each other and from the cardio-intestinal regions; all the regions are granular or tuberculate. The carapace is relatively narrow (breadth/length ratio about 1.30). The frontal margin is projecting beyond the orbits and the submedian lobes advanced compared to the lateral that are distinct but feeble. The region 2M has, at the most, an indication of a short longitudinal division on its anterior margin. The granules on the dorsal surface of the carapace are stout and the tubercles more or less squamous or rounded, generally much larger on the posterior third of the carapace. The ambulatory legs have the superior margin of the merus furnished with a continuous crest, entire or serrate, or a row of stout, rounded spines in compact lobules. The ambulatory legs are flat, with the superior margin of the merus furnished with a crest, entire or more or less cut into saw-like teeth. The propodus of P5 is very slightly foliaceous with a strong crest on the inferior margin. The dorsal surface of the carapace has the regions furnished with conical, pointed, tubercles, becoming squamiform in the centre and stout and rounded posteriorly. The chelipeds are furnished with conical pointed tubercles, similar to those on the carapace. The ambulatory legs have the superior margin of P2 - P4 bearing an acute crest, on P5 this is cut into acute teeth; on the merus of P2 - P5 a large subterminal node separates 1 or 2 distal teeth; the carpus and propodus of P3 - P5 have, on the superior margin, an acute crest generally divided into teeth. The first pleopod of the male has been figured by Guinot (1977, fig. 77 B). (Serène, 1984)
Type locality: Singapore.
Range: India - coast of Orissa (Alcock, 1898); Japan - (Alcock, 1898), Nagasaki (Parisi, 1916, Guinot, 1969d), Kochi (Yokoya, 1933), Nanki Shirahama, Wakayama and Nagasaki (Sakai, 1939), Kii Nagashima, Wagu, Kii Minabe, Shimogusui, and Nagasaki (Sakai, 1976a), Nagasaki (Guinot, 1979b), Tanabe Bay (Miyake, 1983); Taiwan; China - Guangxi, Guangdong, Fujian, and Zhejiang (Dai & Yang, 1991); Hong Kong; Gulf og Tongking - Haiphong (Guinot, 1979b); Gulf of Thailand; East coast of Malay Peninsula (Guinot, 1979b); Singapore (Walker, 1887).