Six new species of terrestrial crabs (Crustacea, Decapoda, Potamidae) from Thailand

A re-examination of old collections of terrestrially adapted primary freshwater crabs in the family Potamidae from various regions of Thailand, as well as aquarium trade material, revealed two new species from the genus Thaiphusa Ng & Naiyanetr, 1993, T. reginamimus sp. nov. and T. mongkol sp. nov. and four new species from the genus Thaipotamon Ng & Naiyanetr, 1993: T. nandidarbhai sp. nov., T. songkhwae sp. nov., T. suvankorni sp. nov. and T. wangsaphung sp. nov.

Species of Thaiphusa and Thaipotamon are characterised by their inflated, ovoid carapace, but these can be distinguished from one another and other similarly rotund Thai potamids by suites of differences in gonopodal, third maxilliped and sternopleonal morphology. The new species are described and compared with congeners; they can be distinguished primarily by differences in the male gonopod morphology. Identification keys to all species of Thaiphusa and Thaipotamon are provided.