Abstract: The existing Oriental fire-bellied toads (Bombina orientalis) in Beijing are the descendant of more than 200 individuals introduced from Shandong populations in 1927. There were no new individuals introduced along the 89 years of independent evolution, therefor making this population become a good sample of studying wild animal population genetics. In this study, we reported the genetic differentiation of 55 Oriental fire-bellied toad individuals from Beijing and Shandong populations based on mitochondrial control region and 6 microsatellite loci. Mitochondrial markers showed the haplotype diversity of Beijing and Shandong populations were 0.489 and 0.950, and nucleotide diversity were 0.0018 and 0.0033, respectively. Phylogenetic trees and network of haplotypes indicated that the two populations have not genetically separated. Microsatellite markers showed the observed heterozygosity were 0.468 and 0.631, and expected heterozygosity were 0.548 and 0.701 for Beijing and Shandong populations, respectively. Structure analysis categorized the 54 successfully amplified individuals into Beijing and Shandong genetic clusters. In general, the Beijing population showed relatively low genetic diversity, which indicated a trend of genetic isolation draw back, but it was still at a moderate level for maintaining normal existence. Thus, there is no need to reintroduce new individuals from Shandong population.

Key words: Bombina orientalis, mitochondrial DNA markers, microsatellite markers, independent evolution, genetic variation