Unmasking Pachytriton labiatus (Amphibia: Urodela: Salamandridae), with description of a new species of Pachytriton from Guangxi, China.

Examination of the lectotype and paralectotypes of Pachytriton labiatus ( Unterstein, 1930 ) from southern China revealed that the specimens do not represent a member of Pachytriton, but are identical with a newt of another genus, Paramesotriton ermizhaoi Wu et al., 2009 also described from southern China. We suggest that Pac. labiatus should be transferred to Paramesotriton as a senior synonym of Par. ermizhaoi. We compared the morphology of the northeastern and southwestern groups of newts previously called Pac. "labiatus" with special reference to age and sexual variations. As a result, we confirmed that the two groups are differentiated sufficiently to be treated as different species. In this report, we revive the name Pac. granulosus Chang, 1933 to refer to the northeastern group of Pac. "labiatus," and at the same time, describe a new species representing the southwestern group.