A close phylogenetic relationship of unisexual Ambystoma (JPB39932) and Kentucky A. barbouri (JPB34342) inferred from mtgenome phylogeny. Other species are incorporated to introduce calibration points for molecular dating analyses, and to serve as outgroups. Left numbers along branches represent the Bayesian posterior probabilities (BPP) and right numbers represent bootstrap proportions (BSP) derived from the parsimony analysis. BPP and BSP below 50 are not shown. Branch lengths are estimated by the Bayesian inference.