Multiple data revealed two new species of the Asian horned toad Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from the eastern corner of the Himalayas

Abstract

Multiple disciplines can help to discover cryptic species and resolve taxonomic confusions. The Asian horned toad genus Megophryssensu lato as a diverse group was proposed to contain dozens of cryptic species. Based on molecular phylogenetics, morphology, osteology, and bioacoustics data, the species profiles of Megophrys toads in the eastern corner of Himalayas in Medog County, Tibet Autonomous Region, China was investigated. The results indicated that this small area harbored at least four Megophrys species, i.e., M. medogensis, M. pachyproctus, Megophrys zhouisp. nov., and Megophrys yeaesp. nov., the latter two being described in this study. Additionally, the mitochondrial DNA trees nested the low-middle-elevation and high-elevation groups of M. medogensis into a monophyletic group, being in discordance with the paraphyletic relationship between them revealed in the nuclear DNA trees. The findings highlighted the underestimated biodiversity in Himalayas, and further indicated that the Megophrys toads here have been probably experienced complicated evolutionary history, for example, introgression between clades or incomplete lineage sorting and niche divergences in microhabitats. Anyway, it is urgent for us to explore the problems because these toads are suffering from increasing threats from human activities and climatic changes.