Abstract
Lentipes ptasan sp. nov. is described based on specimens collected from Taiwan and Mindanao Island. It is a large-sized Lentipes species distinguished by several male-specific characteristics, including an upper lip protruding beyond snout obviously, fewer premaxillary tricuspid teeth, two black lines running from the front of the eye through the nostrils to the tip of the snout, a wide brown longitudinal band at the base of the anal fin, and the distinctive nuptial coloration featuring a brown vertical band extending from back to belly on the middle of the body. The complex distribution of Lentipes species and their genetic differentiation may be influenced by sexual selection, historical biogeographic events and contemporary ecological processes. However, due to the recent divergence of Lentipes species, 11 out of 14 species could not be distinguished by the cytochrome oxidase subunit I gene. Furthermore, Lentipes mindanaoensis is redescribed, with L. adelphizonus treated as its junior synonym.