Genetic Diversity of Neotropical <em>Myotis</em> (Chiroptera: Vespertilionidae) with an Emphasis on South American Species

<div><h3>Background</h3><p>Cryptic morphological variation in the Chiropteran genus <em>Myotis</em> limits the understanding of species boundaries and species richness within the genus. Several authors have suggested that it is likely there are unrecognized species-level lineages of <em>Myotis</em> in the Neotropics. This study provides an assessment of the diversity in New World <em>Myotis</em> by analyzing cytochrome-<em>b</em> gene variation from an expansive sample ranging throughout North, Central, and South America. We provide baseline genetic data for researchers investigating phylogeographic and phylogenetic patterns of <em>Myotis</em> in these regions, with an emphasis on South America.</p> <h3>Methodology and Principal Findings</h3><p>Cytochrome-<em>b</em> sequences were generated and phylogenetically analyzed from 215 specimens, providing DNA sequence data for the most species of New World <em>Myotis</em> to date. Based on genetic data in our sample, and on comparisons with available DNA sequence data from GenBank, we estimate the number of species-level genetic lineages in South America alone to be at least 18, rather than the 15 species currently recognized.</p> <h3>Conclusions</h3><p>Our findings provide evidence that the perception of lower species richness in South American <em>Myotis</em> is largely due to a combination of cryptic morphological variation and insufficient sampling coverage in genetic-based systematic studies. A more accurate assessment of the level of diversity and species richness in New World <em>Myotis</em> is not only helpful for delimiting species boundaries, but also for understanding evolutionary processes within this globally distributed bat genus.</p>