[Population genetic structure of Pelophylax nigromaculata in Chinese mainland based on mtDNA control region sequences].

Molecular genetic data were used to investigate population genetic structure and differentiation of Pelophylax nigromaculata (Anura: Ranidae). Frogs were collected from 12 localities across Chinese mainland. Sample sizes of up to 10 frogs per population were assayed for mitochondrial control region sequence variation. The aligned 685 bp of the 5'CR include 111 variable sites. Sixty-seven haplotypes were defined. Most of the haplotypes are unique to local populations, only 7 of the 67 are shared among a few local populations. The overall species haplotype diversity is quite high (h = 0.98 +/- 0.005), and the nucleotide diversity is also high (pi = 0.0303 +/- 0.0029). This is corresponding to huge population size and extensive distribution of Pelophylax nigromaculata throughout Palaearctic and Oriental Regions. Phylogenetic tree of mtDNA control region haplotypes based on maximum parsimony algorithm and reconstructed phylogenetic relationships among the local populations based on neighbor joining algorithm all suggest that the haplotypes of Jiling and Liaoning populations in northeastern China have a sister relationship with 10 local populations in northern, central, southern and southwestern China. The analysis of molecular variance (AMOVA), the pairwise FST values and nucleotide divergence all support significant population subdivision between the Jilin-Liaoning group and multi-population group. The most possible cause of the significant genetic subdivision between the two groups might be referred to the effect of Quaternary glaciation. The possible reasons for the lack of obvious geographic structure on the whole in the multi-population group and the genetic differentiation in some local populations of the multi-population group were also discussed.