Hynobiidae Mitochondrial Gene Sequence Analysis And Molecular Systematic Studies

Caudata is the lowest grade in all living vertebrate and the most original amphibians which from hydrophilous to terricolous. Hynobiidae is substrate of Caudata, their closely related ancestors. The origin and evolution of Hynobiidae have been one of the research highlights of evolutionists.In order to study the phylogeny of Hynobiidae, we amplified DNA fragments of 16S ribosomal RNA (16S rRNA ) gene and cytochrome b (Cytb) gene on mitochondrial DNA from Ranodon sibiricus and Ranodon tsinpaensis. PCR products were cloned into PMD18 T vector after 1.0% gelose gel electrophoresis test, purification and callback. We randomizatly choiced the white cluster in selective medium which ampicillin was presented in. These sequences were determined and deposited in the GenBank (accession numbers: AY373459 for Ranodon sibiricus 16S rRNA; AY372534 for Ranodon tsinpaensis 16S rRNA; AY373460 for Ranodon sibiricus Cytb; AY372535 for Ranodon tsinpaensis Cytb). By comparing the nucleotide differences of 16S ribosomal RNA and Cytb sequences among Liua shihi, Pseudohynobius flavomaculatus and Batrachuperus genus from GenBank database, we analyzed the divergences and base substitution among these sequences with the MEGA software. The molecular results support that B. tibetanus, B. pinchonii and B. karlschmidti are classified into three valid species. Liua shihi has closer phylogenetic relationship to Ranodon tsinpaensis than to other species. More our results reveal that Pseudohynobius flavomaculatus is not a synonym of Ranodon tsinpaensis.This study will provide molecular basic data for molecule phylogeny of Hynobiidae deeply.