The Chinese giant salamander exemplifies the hidden extinction of cryptic species

Overexploitation, habitat destruction, human-driven climate change and disease spread are resulting in the extinction of innumerable species, with amphibians being hit harder than most other groups [1Wake D.B. Vredenburg V.T. Are we in the midst of the sixth mass extinction? A view from the world of amphibians.Proc. Natl. Acad. Sci. USA. 2008; 105: 11466-11473Crossref PubMed Scopus (1152) Google Scholar]. Few species of amphibians are widespread, and those that are often represent complexes of multiple cryptic species. This is especially true for range-restricted salamanders [2Wu Y.H. Murphy R.W. Concordant species delimitation from multiple independent evidence: A case study with the Pachytriton brevipes complex (Caudata: Salamandridae).Mol. Phylogenet. Evol. 2015; 92: 108-117Crossref PubMed Scopus (10) Google Scholar]. Here, we used the widespread and critically endangered Chinese giant salamander (Andrias davidianus) to show how genetically uninformed management efforts can negatively affect species conservation. We find that this salamander consists of at least five species-level lineages. However, the extensive recent translocation of individuals between farms, where the vast majority of extant salamanders now live, has resulted in genetic homogenization. Mitochondrial DNA (mtDNA) haplotypes from northern China now predominate in farms. Unfortunately, hybrid offspring are being released back into the wild under well-intentioned, but misguided, conservation management. Our findings emphasize the necessity of genetic assessments for seemingly well-known, widespread species in conservation initiatives. Species serve as the primary unit for protection and management in conservation actions [3Mace G.M. The role of taxonomy in species conservation.Philos. Trans. R. Soc. Lond. 2004; 359: 711-719Crossref PubMed Scopus (539) Google Scholar], so determining the taxonomic status of threatened species is a major concern, especially for amphibians. The level of threat to amphibians may be underestimated, and existing conservation strategies may be inadvertently harmful if conducted without genetic assessment.