Taxonomic revision and phylogenetic study of the tribe Gobionini in China (Actinopteri, Cypriniformes, Gobionidae), with the discussion on the generic character of the genus Mesogobio.

The tribe Gobionini, comprising three genera, is widely distributed across Eurasia, with China representing one of the distribution hotspots. Despite numerous species descriptions over the past decades, a comprehensive taxonomic study of this tribe is still lacking. Both morphological comparisons and molecular phylogenetic analysis based on Cytochrome-b gene have been included in this study. Our results indicate that the previously reported species diversity within this tribe may have been overestimated, with 12 species from two genera identified in China: Mesogobio lachneri, Gobio cynocephalus, G. guentheri, G. soldatovi, G. coriparoides, G. rivuloides, G. macrocephalus, G. tenuicorpus, G. acutipinnatus, G. huanghensis, G. tumenensis, and G. fushunensis. The diagnostic key for separating Gobio and Mesogobio is revised based on swim bladder morphology. In the genus Gobio, the swim bladder is well developed, with a total length approximately two-thirds that of the coelom. In contrast, the swim bladder of the genus Mesogobio is reduced, with a total length of approximately half that of the coelom. A diagnostic key to the species distributed in China is also provided.