﻿AbstractThe systematics of the potamid freshwater crabCryptopotamonanacoluthon(Kemp, 1918) is clarified, and its generic position inSinolapotamonTai & Sung, 1975, is confirmed based on morphological comparisons, geographical information and phylogenetic analyses. A new species ofSinolapotamon,Sinolapotamoncirratumsp. nov.is described from the Guangxi Zhuang Autonomous Region of China.Sinolapotamoncirratumsp. nov.is distinguished from its congeners by the combination of characters of its carapace, third maxilliped, anterolateral margin, and unique male first gonopod. Phylogenetic analyses based on partialCOX1, 16S rRNA and 28S rRNA genes also support the species as new.