Rathbun, 1909
Female: Carapace nearly hexagonal rather than trapezoid, with weakly convex antero-lateral, lateral and postero-lateral angles; dorsal surface not strongly convex in most specimens, being provided with a pair of submedian longitudinal, shallow depressions. Fronto-orbital border distinctly thickened and almost transverse as a whole together with each anterior border of carapace to antero-lateral angles of both sides; front weakly deflexed obliquely downward and slightly protruded forward from general level of fronto-orbital border, having a median shallow but distinct depression; cornea usually invisible but occasionally distinct in dorsal view; upper orbital border usually transverse or only weakly convex forward and rather distinctly separated from anterior border of carapace, but in some specimens oblique for most of its length and gently continuous with anterior border of carapace.
Chelipeds comparatively heavy and much thicker than ambulatory legs. Merus and proximal half of carpus just fitted to hepatic region below antero-lateral angle of carapace. In most specimens the palm is widened distally or the upper border is weakly concave for its proximal half, making a slender appearance of palm. Fingers about half as long as palm and provided with short, soft hairs on inner surfaces and prehensile edges, being armed with a thin triangular tooth near proximal part of movable finger and with two smaller teeth; tips of both fingers tuberculated and confronted with each other with 90° in movable finger and 45° in immovable finger to the long axis.
Ambulatory legs, especially first two pairs, rather stout with compressed meri. Dactyli of first two pairs claw-like and half as long as propodi. Third ambulatory leg similar to the preceeding two legs, but the merus is apparently more slender; dactylus variable in its length from about half as long as, to subequal to propodus, but always longer than dactyli of the preceeding two legs and shorter than dactylus of the last leg. Last leg much shorter and slenderer as usual; dactylus equal to propodus in length, being provided with soft hairs of various lengths along its whole inner margin and on one-third of its distal upper surface, and with five spinules on inner margin near the tip.
Male: Carapace excluding frontal region is exactly circular, and frontal region protruded forward about 1/5 as long as carapace proper; dorsal surface is evenly but fairly strongly convex in both directions, with very blunt, thick lateral margins along its anterior half; gastro-cardiac separation indicated at each lateral end by a shallow depression, being about 1/3 the breadth of carapace; whole dorsal surface devoid of hairs, with sparse minute pits along entire length of both lateral margins and with some wrinkles along each anterior part of lateral margins. Front directed very weakly downward, dorsally covered with minute pits, and provided with short setae along anterior margin and on dorsal median, shallow depression. In life the carapace was covered with chromatophores as represented in the text-figure 3.
Chelipeds and ambulatory legs covered with short setae, especially along margins. Chelae similar to those of female in shape and armature of fingers. First three pairs of ambulatory legs subequal in length and shape; in second and third pairs, each merus provided with long hairs along posterior margin, each carpus with a row of long hairs on its upper surface from basal part of posterior border to distal part of anterior border, and each propodus fringed with a row of long hairs along anterior part as continuation of a row of carpus; dactyli of three pairs not much different from each other, being rather short and subequal to one another. Last pair about 2/3 as long as preceeding pairs, with a fringe of long hairs each along posterior margins of merus and propodus; dactylus subequal to those of preceeding pairs, but slenderer, and fringed with longish hairs along both margins. (Takeda & Konishi, 1988)
Type locality:
Range: Mergui Archipelago (de Man, 1887); Sumatra - Padang (de Man, 1887); Japan - Mukaishima, Hiroshima Pref. (Takeda & Konishi, 1988); Philippines - Burias (Bürger, 1895); Indonesia - Noordwachter Island, Jakarta Bay (de Man, 1888d).