Systematic Status of Gongshan Population of Paa chayuensis based on Morphological Characters and Partial Sequences of Mitochondrial 12S and 16S rRNA Genes

The systematic status of Gongshan population of Paa chayuensis has long been disputed.In this study,the phylogenetic relationships among one topotype of Paa chayuensis from chayu population and 4 samples from Gongshan population have been analyzed based on partial sequences of mitochondrial 12S and 16S rRNA genes.The average genetic distance between the two populations is only 0.002,and the topotype of Paa chayuensis nests with Gongshan population in the phylogenetic tree,therefore,it's suggested that the two populations belong to the same species Paa chayuensis.The results of comparisons of the external characters and 29 morphological measurements of 32 topotypes of Paa chayuensis and 8 specimens from Gongshan population indicat that Gongshan population is quite different from the topotypes of Paa chayuensis.It's suggested Paa chayuensis classified into two subspecies.