Two new species of freshwater crabs are described from a hillstream in Chixi Town, Taishan City, Guangdong Province, China: Megapleonum taishanense sp. nov. and Cantopotamon chixiense sp. nov. The two new species are sympatric and are similar in size, colour and superficial appearance in the field. Inspection of key morphological characters sets them apart as undescribed species from two different genera. Megapleonum taishanense sp. nov. and Cantopotamon chixiense sp. nov. can immediately be separated from their respective congeners by their unique G1 morphology but also their combination of carapace, maxilliped 3 and male pleon characters. A phylogeny constructed using the mitochondrial COI gene places Cantopotamon chixiense sp. nov. in its own clade as sister to C. yangxiense Huang, Ahyong & Shih 2017 and a previous 16S rRNA gene study has already shown that Megapleonum taishanense sp. nov. represents an independent clade within Megapleonum Huang, Shih & Ahyong 2018, supporting the current taxonomic treatment of both new species.
Huang et al. (Thu,) studied this question.