A new cave-dwelling species of the genus Triplophysa (Cypriniformes, Nemacheilidae) from southwest China

Based on morphological and molecular data, we described a new cave-dwelling species, Triplophysa xiuwenensis sp. nov., from the karst region of southwest China. The new species can be distinguished from its congeners by the following morphological characteristics: body scaleless without pigmentation; eye diameter of HL with 4.6–6.7 %; tip of pelvic fin not reaching anus; outer rostral barbel reaching to posterior margin of eyes; 14–15 branched caudal fin rays.

Phylogenetic relationships based on the mitochondrial cytochrome b (Cyt b) gene support the validity of the new species. The discovery of the new species brings the number of cave-dwelling Triplophysa species in Guizhou Province to 15, making it the region with the highest number of Triplophysa cave species in the southwestern karst area.