Perinia tumida

Perinia tumida is a crab species from the family of the Epialtidae.

Description

A small species with carapace broadly pyriform, rounded behind and slightly longer than broad. The dorsal surface uneven and indistinctly tuberculated; the gastric region weakly convex, tubercles obsolete besides a pair of rudimentary ones placed side by side on the metagastric region; cardiac region convex, mounted with several small tubercles; intestinal region armed with two small tubercles arranged side by side near the posterior margin; hepatic region very small, armed with a tubercle on the lateral border behind the postocular cup. The branchial regions are deeply separated by a curved groove from both hepatic and cardiac regions; of the branchial tubercles, two are found on the antero-lateral margin behind the hepatic tubercle, the other two are large and rounded, placed along the antero-lateral margin, and two other small ones scattered inside of them. On either side of the cardiac protuberance is a large elongate tubercle and another small indistinct one in front of it.
The pseudorostral horns are very short, the tips are, contrary to the figure of Dana, curved inward, leaving a rounded median interspace. No trace of upper orbital sinus, the supraocular eave and the postocular cup being completely fused together, the preocular tooth small and obtuse. The basal antennal article is broad and stout, its antero-external angle is produced into a robust process, which can be observed from above on either side of the pseudorostrum.
Chelipeds of male very stout; merus short, with two teeth on the upper inner border, of which the distal one is more prominent; the upper outer surface also with two obtuse tubercles while the lower surface is sparingly pilose. Carpus and propodus smooth, the latter somewhat compressed and cristate above. Tip of the fingers not so distinctly hollowed in our specimens, the cutting edges are minutely denticulated.
The ambulatory legs are robust and short; merus provided with two obtuse spines on the anterior crest, with two or three tubercles on the upper surface, of which the distal one is very often predominant in size. Carpus is armed with a strong spine on the anterior border, propodus compressed and pilose. The dactylus is armed with 4 or 5 denticles on the posterior border, the horny tip being strongly curved.

Distribution

Indo-Pacific Ocean from Tanzania and Madagascar, also Red Sea, to New Caledonia and French Polynesia, also Hawaii.