Liobagrus brevispina , a new species of torrent catfish (Siluriformes: Amblycipitidae) from the upper Chang‐Jiang basin, South China

A new species of Liobagrus is unearthed in the Nan-Jiang flowing into the Jialing-Jiang of the upper Chang-Jiang basin in which currently recognized Chinese congeners have a concentrated distribution. This small-sized (less than 100.0 mm LS ) torrent fish belongs to the species group defined by the presence of a smooth posterior edge of the pectoral-fin spine and upper and lower jaws of equal length or a lower jaw slightly longer than the upper jaw in length. It is distinct from Liobagrus aequilabris and Liobagrus formosanus by the presence of a pectoral-fin spine extending short of (vs. beyond) the vertical through the dorsal-fin origin, maxillary barbels reaching the middle of the pectoral fin (vs. pectoral-fin insertion or slightly beyond), 17-19 anal-fin rays (vs. 15-16 in L. formosanus), 39-41 (vs. 35-37 in L. aequilabris) post-Weberian vertebrae and the pectoral-fin spine length 3.6%-7.4% of LS (vs. 7.6-10.5 in L. aequilabris). It differs from Liobagrus marginatoides by the presence of upper and lower jaws of equal length (vs. a lower jaw slightly longer than the upper jaw in length) and a rounded or unevenly rounded (vs. subtruncate) caudal fin. The validity of the new species is confirmed by its monophyly recovered in a cytochrome b gene-based phylogenetic analysis and its significant genetic distance with sampled congeneric species.