What’s in a name? Using species delimitation to inform conservation practice for Chinese giant salamanders ( Andrias spp.)

Abstract

Genetically-defined biodiversity units must align with practical conservation frameworks, and most conservation is conducted at the species level. Chinese giant salamanders have traditionally been interpreted as the single widespread species Andrias davidianus, but molecular studies have reinterpreted this taxon as representing multiple allopatric clades, and competing taxonomic hypotheses support different numbers of candidate species. We conducted species delimitation analyses using tree-based models (General Mixed Yule Coalescent, Poisson Tree Processes) and alignment-based models (Bayesian Phylogenetics and Phylogeography) to interpret diversification across Andrias within a comparative systematic framework, using 30 mitogenomes representing all recognised Chinese clades. Nearly all tested models provide support for at least seven statistically-resolved Chinese species-level lineages, and most provide support for nine species. Only four species have available names. Chinese Andrias populations are Critically Endangered, but unnamed species cannot be incorporated into national or international conservation frameworks and risk being excluded from recovery efforts. We urge taxonomists and conservation practitioners to focus more attention on the world’s largest amphibians, and non-standard taxonomic approaches may be required to name these species before they disappear.