Sakai, 1965
The carapace is broadly semi-elliptical, and its dorsal surface is flat from side to side, almost smooth and sloping fore and aft; the regions are ill-defined. The frontal margin is almost straight, the median emargination distinct but shallow and the lateral angles not lobulate at all. The upper orbital margin is entirely continuous with the lateral frontal angle, i.e. no preorbital tooth or hiatus may be found.
The antero-lateral borders extend obliquely backwards, are thin and cristate, marked with two vestigial fissures; the lateral angles are rounded. The postero-lateral borders are moderately concave.
The antennal flagellum arises directly from the antennal hiatus towards the orbit, and does not stand out close to the preorbital hiatus, as in other related genera. The efferent branchial ridges are confined to the posterior part of the endostome; they are subparallel with each other and rather rectangular against the anterior ridge of the buccal frame.
The chelipeds are very slender, the merus long and rather narrow, the carpus very small, and the propodus also slender and distally broadened, much longer than the dactylus. The ambulatory legs are very thin and slender. The abdomen of both sexes has the terminal segment longer than the penultimate.
The new genus seems to be intermediate between Atergatis de Haan and Liagore de Haan. In genus Atergatis, however, the carapace is convex in both directions, and the frontal margin is sinuous and the lateral angles markedly lobulate; there is a sinus between the lateral frontal lobule and the preorbital margin, whence the antennal flagellum arises. The antero-lateral borders are markedly convex and cristate. The chelipeds and ambulatory legs are very robust, each segment being markedly broader than long. The efferent branchial ridges are oblique and parallel to the lateral ridges of the buccal orifice; the penultimate segment of the abdomen is distinctly longer than the terminal segment.
In genus Liagore the carapace is also convex in both directions but the antero-lateral borders are entire and not cristate. The fronto-orbital margins are just like those of the new genus, but in Liagore there is a short and shallow sinus between the lateral frontal angle and the supraorbital margin. The chelipeds are robust and heavy; the ambulatory legs are very slender as in the new genus, but the merus is not cristate along the anterior margin. The ratio of the lengths of the terminal and penultimate segments of the abdomen is the same as for the new genus. (Sakai, 1965)
Type species: Paratergatis longimanus Sakai, 1965.
Species treated:
Paratergatis longimanus Sakai, 1965