A New Species of Pachytriton (Amphibia: Caudata: Salamandridae) from Anhui, China.

China is a global hotspot for amphibian biodiversity, yet under-explored montane regions harbor undiscovered cryptic species. Using integrative taxonomy, we describe a new salamandrid species, Pachytriton cheni sp. nov., from Qingliangfeng Nature Reserve, Anhui. Phylogenetic analyses of mitochondrial (ND2, cytb) and nuclear (RAG1, POMC) genes strongly support it as a monophyletic sister lineage to P. granulosus, with significant mitochondrial p-distances (4.39-10.22%) and unique nuclear haplotypes. Bayes factor species delimitation under the multispecies coalescent model (MSC) decisively rejects conspecificity with P. granulosus (2lnBF = 24.52). Morphologically, it is diagnosed by its small size; oval, narrow head (length > width); nearly black dorsum lacking bright orange spots; smooth skin; occipital V-shaped ridge; orange-red abdomen with brown markings; prominent neck folds; and minimal digit gap when limbs are adpressed. This discovery increases Pachytriton species to ten, highlights high-elevation montane ecosystems as key biodiversity refuges in East China, and underscores the need for further surveys to clarify the genus's phylogeny.