Integrative taxonomy and geographic variation of Myotis dinellii and M. levis (Chiroptera, Vespertilionidae) Argentinean populations

Abstract

Myotis is one of the most diverse genus of bats in the world, with ca. 35 species recognized for the Neotropics. Among these, Myotis dinellii Thomas, 1902 has been alternatively treated as a valid species or as a synonym of Myotis levis (I. Geoffroy, 1824). Previous phylogenetic analysis of DNA sequences suggests that both taxa could constitute a single species. To test this hypothesis, we employed both qualitative and quantitative morphological approach and a re-examination of the available genetic data, in order to integrate multiple lines of evidence. Principal component and discriminat analyses failed to separate morphologically M. dinellii from M. levis. Also, mitochondrial sequences of the cytochrome b gene showed very low divergence, and the taxa did not form reciprocally monophyletic groups. Therefore, morphological and genetic analyzes provides a strong support to the conspecificity between M. dinellii and M. levis. This hypothesis is also supported by our direct examination of some topotypes of M. dinelli and color photograph of the syntype of M. levis. The morphological variation found within the studied samples is more likely explained by geographic variation, involving a west-east gradient in overall size. Based on these findings, we propose that M. dinellii is a junior synonym of M. levis.