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Data presented herein provide records of four species of bats new to the fauna of the Antillean island of Saba — Monophyllus plethodon, Ardops nichollsi, Tadarida brasiliensis, and Molossus molossus. Together with three species previously recorded from the island – Brachyphylla cavernarum, Artibeus jamaicensis, and Natalus stramineus – the chiropteran fauna of the island is documented to be composed of seven species. Our analysis of species/area relationships for West Indian bats provides a slope value of z = 0.177 and R2 = 0.76; therefore, the bat fauna of the West Indies has the flattest slope for this relationship of any West Indian group. This relationship is best explained by a propensity for over water dispersal by West Indian bats. We propose to unite the chiropteran faunas of the islands of Anguilla, Antigua, Barbuda, Nevis, Saba, St. Barthélemy, St. Eustatius, St. Kitts, and St. Martin by recognizing them as the Northern Antillean Faunal Area. Given the small size of Saba (12 km2) and the even smaller effective habitat for non-molossid bats (4 km2), conservation concerns are expressed for the future of the fauna and some recommendations are made for its preservation.
The Mauritius flying fox Pteropus niger is distributed on the islands of Mauritius and La Réunion in the western Indian Ocean. Although recent studies have examined the phylogenetics and systematics of this genus, relatively few have assessed the population genetics of species distributed on oceanic islands and no study has focused on the demographics of P. niger. Here, we present mitochondrial DNA sequence data from 39 individuals of P. niger collected from four main colonies distributed throughout Mauritius. Our results indicate that the Mauritian population of P. niger is likely panmictic, with moderate to high levels of gene flow occurring among colonies distributed across the island. Collectively, our sequence data suggest moderate levels of genetic variation within the population. These findings will help to inform ongoing conservation and disease surveillance initiatives.
We describe and formally name a species of bonneted bat (genus Eumops), which is a member of the E. glaucinus complex. Closely related species are E. glaucinus, E. ferox, and E. floridanus. The conceptual basis for the description of this species is the Genetic Species Concept with speciation by the Bateson-Dobzhanzky-Muller model. The new species is distinguished from all other species of bats by its unique karyotype (2N = 38, FN = 54), sequence of the mitochondrial cytochrome-b gene, and genetic markers revealed through analysis of Amplified Fragment Length Polymorphisms. The series from the type locality (Ecuador, Guayas) is comprised of seven specimens. Morphologically, the new species is smaller than E. floridanus and E. glaucinus, but is indistinguishable from E. ferox. The new species is significantly smaller in size than E. glaucinus in six out of eight measurements and is distinguishable from E. glaucinus based on length of maxillary toothrow and zygomatic breadth. The geographic range of E. wilsoni, as currently documented, is the dry forests of southwestern Ecuador and adjacent northwestern Peru. We propose the common name for this species be Wilson’s bonneted bat.
Species diversity and species limits of the small fruit-eating bats, genus Dermanura (Phyllostomidae: Stenodermatinae) were examined. Estimates of species diversity based on classical morphological criteria (current taxonomy) were compared to diversity estimates based on monophyly and cytochrome-b sequence divergence. The most recent taxonomic list included nine species, whereas the genetic based list contained 11: anderseni, azteca, bogotensis, cinerea, glauca, gnoma, phaeotis, rava, rosenbergi, tolteca, and watsoni, of which three (bogotensis Andersen, rava Miller, and rosenbergi Thomas) have been considered synonyms of cinerea, glauca, phaeotis, and tolteca by previous authors. In addition, we consider incomitata to be a synonym of watsoni. Phylogenetic analyses of mtDNA sequences resolved the interrelationships among taxa and prompted us to re-evaluate some morphological characters that support the distinction of all the recognized taxa, therefore providing a robust estimate of species status. A phylogenetic tree revealed a geographic component to the diversification of Dermanura, including a historical connection between western Andean and Middle American biota. In South America, no species has been recorded from both sides of the Andes Mountains, and at least one clade (glauca, gnoma, and bogotensis) is restricted to the eastern versant of the Andes. Using genetic data (monophyly and genetic distance) to identify species we were able to produce testable genealogical and biogeographic hypotheses to facilitate further studies.
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