Carapace rather narrow, with dorsal surface strongly convex in both directions; uniform short setae, but no granules; areolae indistinct except for the shallowly separated gastric region; four anterolateral teeth tuberculated, each with a sharp spine directed obliquely upward; some sharp, small granules on subhepatic region. Front prominent, with each lobe armed with three spines; each lobe separated from a long spine at lateral end of front by an U-shaped sinus. Six long spines on infraorbital border. Both chelipeds of male different in size, being covered with spiniform granules and stiff setae; two or three spines on upper margin of merus, some on upper surface of carpus, and some on upper margin of palm are markedly long. Ambulatory legs slender, and armed with some spines on anterior borders of each merus and carpus; in addition, one spine each at median part of anterior border of two to four pairs.