Phylogeny of the Genera with Oromandibular Discs in the Subfamily Labeoninae (Teleostei: Cyprinidae) with Descriptions of Two New Genera

Abstract

The aim of this study was to understand the systematic relationships between certain fish genera with oromandibular discs in the Labeoninae. At the same time, this was an opportunity to clarify the taxonomic status of certain species in the genera Ageneiogarra, Garra, Placocheilus, and other taxa distributed in China. Morphological comparison and molecular analysis were used in the study. The results showed that the genera with oromandibular discs had no recent common ancestor and that their oromandibular discs were the result of convergent evolution in different evolutionary lineages. Due to the homogeneity of their habitats, these fish have evolved oromandibular discs with similar appearance and structure. Both morphological and molecular evidence suggests that (1) Placocheilus cryptonemus distributed in the Nu-Jiang (the Upper Salween River Basin), Yunnan, China, represent a new genus, here described as Pseudoplacocheilus, and (2) Garra micropulvinus occurring in the Panlong-He (the upper portion of the Lo River, a branch of the Red River Basin) from Wenshan, Yunnan, represents another new genus, here described as Supradiscus.