A taxonomic revision of the freshwater crab genus Parvuspotamon Dai & Bo, 1994 (Decapoda, Brachyura, Potamidae), with descriptions of a new genus and two new species

The taxonomy of the potamid crab genus Parvuspotamon Dai & Bo, 1994, with two species native to Yunnan province of southwest China, is revised based on morphological and molecular data. In order to stabilise the taxonomy of these species (and the genus), two separate genera are hereby designated: Parvuspotamon and Songpotamon gen. nov. While Parvuspotamon is restricted to P. yuxiense Dai & Bo, 1994, as a monotypic genus, P. dixuense Naruse, Chia & Zhou, 2018, is transferred to a new genus, Songpotamon gen. nov. In addition, two new species of Songpotamon gen. nov. are described herein: S. funingense sp. nov. and S. malipoense sp. nov. Songpotamon gen. nov. morphologically most resembles Parvuspotamon and Chinapotamon Dai & Naiyanetr, 1994, but can be distinguished by the combination of characters in the carapace, third maxilliped, thoracic sternites, and male first gonopod. The genetic data derived from the mitochondrial 16S rDNA also supports the monophyly of these new taxa.