A new species of the genus Protocobitis, was discovered in an underground water source （110m depth） located about 5km away from the county town of Wuming, Guangxi, China, in May 2006. The new species, Protocobitis polylepis sp. nov., is distinguished from the single congener by the following characteristics：1） light black pigmentation present vs. no pigmentation; 2） entire body covered with scales except for its head and abdomen vs. rudimentary scales present only along the midline of the body; 3） head length 24.1%-24.8% of SL vs. 19.8%-22.1% of SL; 4） body depth 16.2%-16.3% of SL vs. 11.5%-13.0% of SL; 5） Inner rostral barbel length 19.8%-21.0% of head length vs. 9.4%-11.8% of head length; outer rostral barbel length 28.6%-30.2 % of head length vs. 15.3%-21.8% of head length; maxillary barbell length 44.6%-46.0% of head length vs. 22.4%-31.8% of head length.
