Cryptic diversity not only introduces confusion to taxonomic studies, but it also poses major challenges to conservation and environmental legislation. One such troubling group are the Mountain Dragons in the genus Diploderma in Southwest China. Previous studies have suggested that the genus contains considerable cryptic diversity, particularly in the D. flaviceps complex. Owing to taxonomic confusion, micro-endemic lineages are still neglected by the Chinese wildlife protection laws, despite their urgent conservation needs. Combining multivariate morphological and multi-locus phylogenetic data, we provide the first integrative systematic revision of the genus Diploderma. Specifically, we confirm that the six examined populations of D. cf. flaviceps from the upper Jinsha and Yalong River Valleys in Sichuan and Yunnan Provinces represent six cryptic, undescribed lineages, and we describe each of them as a new species. With the updated taxonomy and distribution information, we discuss the taxonomy of the D. flaviceps complex in Southwest China, provide an updated diagnostic key along with distributional ranges for all species of the genus, and discuss some of the suspicious records of other congeners in China. Lastly, we evaluate the IUCN status of each of the six new species and highlight the major challenges for Diploderma conservation in China due to delayed environmental legislation and misleading conservation assessments.

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species‐delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty‐eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.

We describe a new species of the genus Hebius and provide evidence for the validity of H. septemlineatus comb. nov. . Morphological and molecular analyses of Hebius specimens collected in Yunnan Province, China, revealed three distinct lineages, namely the newly described Hebius weixiensis sp. nov. , as well as H. octolineatus (Boulenger, 1904), and H. septemlineatus comb. nov. (Schmidt 1925), which is removed from synonymy with H. octolineatus . Based on mitochondrial genealogy, Hebius weixiensis sp. nov. is sister to H. septemlineatus comb. nov. , while H. octolineatus is sister to H. bitaeniatus . The new species and H. septemlineatus comb. nov. showed considerable genetic divergence from their recognized congeners (uncorrected P- distance ≥3.9%). Furthermore, the new species and H. septemlineatus comb. nov. can be diagnosed from closely related congeners by a combination of pholidosis characters.