Glyptothorax pulcher (Siluriformes, Sisoridae), a new species from the upper Pearl River of Yunnan and Guangxi, southwest China

A new species of the genus Glyptothorax, Glyptothorax pulcher sp. nov. is described from the Tuoniang River, the Pearl River Basin, in south-eastern Yunnan Province and western Guangxi Zhuang Autonomous Region, China. This new species most closely resembles G. quadriocellatus in overall morphology, including similar outline appearance, skin tubercles and colour pattern. It can be distinguished from its congeners that are found in east of the Red River in China by the following combination of characteristics: distinctive colour pattern, skin with sparse soft tubercules, dorsal surface of head smooth, thoracic adhesive apparatus (TAA) broad (length of 1–1.2 times its width, width of TAA 12.0–14.3 % SL), adipose-fin base short (11.7–15.4 % SL), caudal peduncle deep and short (13.7–17.5 % SL in length, 10.3–12.3 % SL in depth).

Its validity is further confirmed by molecular phylogenetic analysis, based on mitochondrial CO I and Cyt b gene sequences, indicating it forms a sister group with G. pallozonum. The estimated K 2 P genetic distances between the new species and G. pallozonum range from 5.7 % to 6.0 %. In addition, phylogenetic evidence also suggests that G. zhujiangensis not be a valid species, but rather a junior synonym of G. pallozonum in this study.