Species identification and evolutionary inference of the genera Megalobrama and Parabramis (Cyprinidae: Cultrinae) in China

Abstract

The species boundaries and evolutionary relationships of two closely related genera, Megalobrama and Parabramis, were inferred from the partial mitochondrial cytochrome oxidase subunit I (COI) gene, NADH dehydrogenase subunit 2 (ND2) gene and their concatenated segment. Phylogenetic reconstructions showed that among the three breams, Megalobrama amblycephala and Megalobrama skolkovii are more closely related to each other than either is to Megalobrama terminalis. The taxonomy of M. pellegrini should be reconsidered. The divergence time estimation based on the assumption of a global molecular clock indicated that speciation and dispersal of the two genera might have occurred at approximately Pliocene to Late Pleistocene, due to major paleo-environmental events associated with monsoon evolution and the formation of the Three Gorges of the Yangtze River.

• COI
• molecular clock
• mtDNA
• ND2
• phylogenetic relationships
• species validity

Acknowledgements

We are grateful for the help of Cao L, Yang M, Chi W and Tao WJ for software analysis. P. Edwards edited the final manuscript.

Declaration of interest

This study was funded by the earmarked fund for Modern Agro-industry Technology Research System entitled “Staple Freshwater Fishery Industry Technology System” (No. CARS-46-05) and Fundamental Research Funds for the Central Universities (No. 2011PY023).