The broad geographic range of true toads (genus Bufo) in the Eastern Palearctic has resulted in hidden diversity, uncertain origins of species complexes and unclear taxonomic boundaries. To reconstruct the historical biogeography of Asian Bufo, and resolve the taxonomy of problematic species complex such as B. gargarizans in East Asia, we sampled 433 individuals across the totality of the B. gargarizans complex range.
We integrated predictive phylogeographic tools and advanced taxonomy using multi-locus genetic fragments and we determined that the combined effects of long dispersal and glacial refugia resulted in deep divergence within the B. gargarizans complex. The species delimitation modelling supported the independent evolutionary lineage of the northern-most population in the species complex. The species distribution model and migration patterns suggested a difference in ecological requirements between the populations east and west of the Yellow Sea, supporting the segregation of the Bufo clade east of the Yellow Seafrom the widespread B. gargarizans.
Resolving the taxonomic boundaries of the B. gargarizans complex, we resurrected Bufo sachalinensis, also giving it a Chinese common name as two species from the clade are now in the nation: Dōng Běi Chán Chú. Additionally, we highlight that only B.sachalinensis occurs on the Korean peninsula and Russia, divided into two conservation units: B. sachalinensis sachalinensis in Russiaand B. sachalinensis cf. sachalinensis, in southern Korea (where the subspecies still needs to be described). We recommend a separate conservation management system to preserve these subspecies.
Further details on this scientific publication are available from eLifeScience https://elifesciences.org/articles/70494 .