On the variation, distribution and evolutionary history of Myotis armiensis (Chiroptera, Vespertilionidae) along Neotropical mountain ranges

Myotis armiensis was recently described from specimens collected in the mountain ranges of Costa Rica, Panama, and Ecuador. During a systematic revision of Neotropical Myotis, we identified additional specimens from Venezuela and Colombia. Using an integrative approach that combined morphological traits, cytochrome b sequences, and ecological niche modeling, we assessed the geographic variation of M. armiensis. Our findings indicate that this species can be structured into two allopatric populations: one in the Talamanca Cordillera of Central America, and another restricted to the South American Andes and Cordillera de La Costa in Venezuela. These populations are reciprocally monophyletic, exhibiting genetic distances greater than 3% and notable morphometric variation. The diversification of this taxon likely occurred during the Pleistocene, possibly driven by environmental fluctuations associated with glacial cycles. It is possible that M. armiensis comprises two recently diverged lineages, but future studies incorporating broader datasets are needed to properly assess the taxonomic status of these populations.