Diversification of the Yellow-shouldered bats, Genus Sturnira (Chiroptera, Phyllostomidae), in the New World tropics

[Display omitted] •Concatenated sequence analyses support generic monophyly, but not subgenera.•Sturnira contains at least 21 monophyletic clades, 3 of which are unnamed.•Sturnira diverged from other stenodermatines in the Miocene, but most of its diversification occurred in the Pliocene.•Initial divergences took place in the Andes, radiating into Central America and Antilles during the Quaternary. The Yellow-shouldered bats, Genus Sturnira, are widespread, diverse, and abundant throughout the Neotropical Region, but little is known of their phylogeny and biogeography. We collected 4409bp of DNA from three mitochondrial (cyt-b, ND2, D-loop) and two nuclear (RAG1, RAG2) sequences from 138 individuals representing all but two recognized species of Sturnira and five other phyllostomid bats used as outgroups. The sequence data were subjected to maximum parsimony, maximum likelihood, and Bayesian inference analyses. Results overwhelmingly support the monophyly of the genus Sturnira but not continued recognition of Corvira as a subgenus; the two species (bidens and nana) allocated to that group constitute separate, basal branches on the phylogeny. A total of 21 monophyletic putatively species-level groups were recovered; pairs were separated by an average 7.09% (SD=1.61) pairwise genetic distance in cyt-b, and three of these groups are apparently unnamed. Several well-supported clades are evident, including a complex of seven species formerly confused with S. lilium, a species that is actually limited to the Brazilian Shield. We used four calibration points to construct a time-tree for Sturnira, using BEAST. Sturnira diverged from other stenodermatines in the mid-Miocene, and by the end of that epoch (5.3Ma), three basal lineages were present. Most living species belong to one of two clades, A and B, which appeared and diversified shortly afterwards, during the Pliocene. Both parsimony (DIVA) and likelihood (Lagrange) methods for reconstructing ancestral ranges indicate that the radiation of Sturnira is rooted in the Andes; all three basal lineages (in order, bidens, nana, and aratathomasi) have strictly or mainly Andean distributions. Only later did Sturnira colonize the Pacific lowlands (Chocó) and thence Central America. Sturnira species that are endemic to Central America appeared after the final emergence of the Panamanian landbridge ∼3Ma. Despite its ability to fly and to colonize the Antilles overwater, this genus probably accompanied the “legions” of Sou