Phricotelphusa sirindhorn n.sp., a new freshwater crab from Thailand (Decapoda, Brachyura, Gecarcinucidae)

In 1986 in the southern part of Thailand, the author collected two specimens of a new species of freshwater crab of the genus Phricotelphusa Alcock, 1909, belonging to the family Gecarcinucidae Rathbun, 1904. The species was found in mountain streams of the Ngao Waterfall Forest Park in Amphoe Muang (= Muang district), Ranong Province. Thirty living specimens of the same species were collected from the same place in 1987. The description of the new species is provided in this paper.