Homatula pycnolepis, a new species of nemacheiline loach from the upper Mekong drainage, South China (Teleostei: Balitoridae)

Homatula pycnolepis, new species, is described from the upper Mekong drainage in Yunnan Province, South China. It resembles H. acuticephala, H. anguillioides and H. erhaiensis in the shared presence of a densely scaled predorsal body, which separates them from all other congeners, but is distinct from H. acuticephala and H. anguillioides in the number of vertical bars on the flank and the shape of both the dorsal and anal fins, and from H. erhaiensis in having the scales of predorsal body not embedded beneath skin, the number of vertebrae and vertical bars on the flank, body shape, and morphometric characters such as head length, caudal-peduncle length and preanal length. Homatula pycnolepis is further distinct from H. anguillioides in intestinal coiling pattern and in the shape of the fronto-parietal fontanelle and operculum, and from H. acuticephala in body shape, caudal-peduncle coloration and thickness, snout shape, and pectoral-fin and pelvic-fin lengths.