Molecular Phylogenetics And Biogeography Of The Brown Frogs In China And Northeast Asia

There are a large number of the brown frogs with plentiful biodiversity and complexphylogenetic relationships distributed in China and Northeast Asia. And their closemorphological similarities always led them difficult to identify. Brown frogs are good modelorganism for studies of vicariance biogeography because of their general feature of low ability tocross oceans, mountains and deserts. In this study, we use four mitochondrial genes and threenuclear genes to address the questions related to phylogenetics, speciation and biogeography ofbrown frogs living in this region. The main results are as followed:(i) We successful reconstructed the phylogenetic relationship of Chinese brown frogs basedon four mitochondrial genes and three nuclear genes. The radiant phylogenetic trees show thatthere were four main clades in Chinese brown frogs. Rana amurensis species group, whichspecies composed of R. amurensis and Rana kunyuensis, as a main clade was first separated fromother Chinese brown frogs. Then Rana chensinensis species group as a main clade separate fromRana maoershanensis and Rana longicrus species group. Interestingly, our analyses show that R.maoershanensis as an independent main clade with phylogenetic position next to R. longicrusspecies group. Our phylogenetics and genetic distance analysis confirmed that R.maoershanensis is a valid species and have a phylogenetic position connect to R. chensinensisspecies group and R. longicrus species group.(ii) We also analysed the phylogenetics and biogeography of the brown frogs around BohaiSea District based on four mitochondrial genes. The results show that there were three mainclades of the brown frogs living in this region and within each clade had two endemicdistribution species with close relationships. Compared the geological history with thephylogenetics and divercent time analyses, we redescribe the evolution history of the brownfrogs living in this region. The evolution and distribution patterns of R. amurensis species groupspecies and Rana dybowskii in this region were all resulted by the isolation of orogenicmovement of Changbai Mountain Range in Middle Miocene. Our analyses also reveal that theevolution history and distribution patterns of part species of R. chensinensis species complex(Rana huanrensis and R. chensinensis from east Qinling, China) not only be affected by theorogenic movement of Changbai Mountain Range, but also spread during Late Miocene whenpart of Yellow Sea basin was land briefly. (iii) For there was much taxonomy confuse of R. dybowskii from Russia Far East, NortheastChina and Korean Peninsula, we analyses the phylogenetics, speciation and biogeography of R.dybowskii and also combined with R. pirica, which inhabit in Sakhalin Island and HokkaidoIsland and have a closely related to R. dybowskii, based on the four mitochondrial genes. Thephylogenetic trees show that R. dybowskii from Russia Far East and Northeast China composed aclosely monophyletic group next to R. chensinensis species complex and confirmed R. dybowskiifrom Northeast China is the real ‘Rana dybowskii’. The phylogenetics and speciation analysesrevealed that R. dybowskii from Korean Peninsula should be considered a distinct species. Theresults of biogeography analyses indicated that the evlution history and distribution patterns of R.dybowskii and R. pirica were affected by Middle Miocene the orogenic movement of ChangbaiMountain Range and the separation of Sakhalin Island and Hokkaido Island from Eurasiancontinent.