Complete mitochondrial genomes of and (Reptilia, Squamata, Colubridae) and their phylogenetic implications.

The complete sequence of the mitochondrial genome is a powerful tool for studying phylogenetic relationships and molecular evolution in various species. In this work, the mitogenomes of and were sequenced and characterized for the first time. The lengths of the and mitogenomes were 17,124 bp and 17,120 bp, respectively, and both included 13 protein-coding genes, 22 tRNAs, two rRNAs and two control regions. The arrangements of these mitochondrial genes were the same in and . In addition, both genome compositions showed A+T bias (59.03%, 60.93%) and had positive AT skews (0.179, 0.117) and negative GC skews (-0.397, -0.348). The phylogenetic results illustrated a close relationship between and the genus . Moreover, was clustered with other snakes and closely related to other Natricinae species. These results will provide references for further research on the phylogeny of Colubridae.