Few studies have explored the role of Cenozoic tectonic evolution in shaping patterns and processes of extant animal distributions within East Asian margins. We select Hynobius salamanders (Amphibia: Hynobiidae) as a model to examine biogeographical consequences of Cenozoic tectonic events within East Asian margins. First, we use GenBank molecular data to reconstruct phylogenetic interrelationships of Hynobius by Bayesian and maximum likelihood analyses. Second, we estimate the divergence time using the Bayesian relaxed clock approach and infer dispersal/vicariance histories under the ‘dispersal–extinction–cladogenesis’ model. Finally, we test whether evolutionary history and biogeographical processes of Hynobius should coincide with the predictions of two major hypotheses (the ‘vicariance’/‘out of southwestern Japan’ hypothesis). The resulting phylogeny confirmed Hynobius as a monophyletic group, which could be divided into nine major clades associated with six geographical areas. Our results show that: (1) the most recent common ancestor of Hynobius was distributed in southwestern Japan and Hokkaido Island, (2) a sister taxon relationship between Hynobius retardatus and all remaining species was the results of a vicariance event between Hokkaido Island and southwestern Japan in the Middle Eocene, (3) ancestral Hynobius in southwestern Japan dispersed into the Taiwan Island, central China, ‘Korean Peninsula and northeastern China’ as well as northeastern Honshu during the Late Eocene–Late Miocene. Our findings suggest that Cenozoic tectonic evolution plays an important role in shaping disjunctive distributions of extant Hynobius within East Asian margins.

Freshwater fishes of the subfamily Gobioninae (Cypriniformes: Cyprinidae) are composed of three major clades, the tribes Gobionini and Sarcocheilichthyini, and a Hemibarbus–Squalidus group. In this study, we determined ten complete fish mitogenomes from eight of all twelve genera in the tribe Gobionini. The ten mitogenomes displayed similar patterns in gene arrangements, codon use and gene overlaps with the length of 16,605–16,617 bp and base compositions slightly A + T bias of 56.1–58.0%. Our phylogeny of the tribe Gobionini revealed that the genera Gobio, Xenophysogobio, Gobiobotia, Saurogobio and Pseudogobio were monophyletic, and other genera Abbottina, Biwia, Microphysogobio and Platysmacheilus were paraphyletic or polyphyletic. The findings indicate that the genera classifications of Gobionini are needed to be further confirmed.

The taxonomy and systematics of Phoxinus (Cypriniformes: Cyprinidae) is still not well-resolved. In this study, we determined the first complete mitochondrial genome (mitogenome) of Phoxinus tumensis. The mitogenome was 17,050 bp in length, including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The overall base composition of the heavy strain was 27.9% for A, 25.5% for C, 28.4% for T and 18.2% for G. The control region was revealed to contain tandem repeats. The mitogenome data of P. tumensis should contribute to clarify the systematics of Phoxinus fishes.