The origin and divergence of Gobioninae fishes (Teleostei: Cyprinidae) based on complete mitochondrial genome sequences

Feb 1, 2016

The gudgeons (subfamily Gobioninae) are a group of cypri-nid fishes primarily distributed in East Asia. However, studies on their origins and divergence are scarce. Here the whole mitochondrial genome sequences of 27 gudgeon species (including one newly determined), 22 other cyprinid species, and two non-cyprinids as outgroups are applied to infer the evolution of the gudgeons. Based on Bayesian and maximum likelihood phylogenetic analyses, the gudgeons were determined to be a monophyletic group which can be further subdivided into four monophyletic clades with strong supports. The divergence times of the gudgeons were estimated using a relaxed molecular clock method; the results indicate that these fishes originated in the early Paleocene (approx. 63.5 Mya) and that the basal Hemibarbus group diverged from the other gudgeon fishes (approx. 58.3 Mya). As an independent group the Coreius began to diverge from the remaining two groups (approx. 54.6 Mya); the most derived two groups diverged from each other (approx. 53.6 Mya). The divergences of the four gudgeon groups were within a relatively short time frame (approx. 58–53 Mya). Based on the reconstruction of evolutionary trends of gudgeon habitat, evidence is provided that supports the origin and differentiation of this fauna as being associated with some special paleo-environmental events occurring from the early Pale-ocene to the Pliocene. The study represents comprehensive molecular dating and character evolution analyses of the gudgeons, and providing a valuable framework for future research in the evolution of the Gobioninae fishes.