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The Azorean batNyctalus azoreumis the only endemic mammal native to the remote archipelago of the Azores. It evolved from a continental ancestor related to the Leisler's batNyctalus leisleriand is considered threatened because of its restricted and highly fragmented distribution. We studied the genetic variability in 159 individuals from 14 colonies sampled throughout the archipelago. Sequences of the D-loop region revealed moderate but highly structured genetic variability. Half of the 15 distinct haplotypes were restricted to a single island, but the most common was found throughout the archipelago, suggesting a single colonization event followed by limited interisland female gene flow. AllN. azoreumhaplotypes were closely related and formed a star-like structure typical of expanded populations. The inferred age of demographic expansions was consistent with the arrival of founder animals during the Holocene, well before the first humans inhabited the Azores. Comparisons with a population ofN. leislerifrom continental Portugal confirmed not only that allN. azoreumlineages were unique to the archipelago, but also that the current levels of genetic diversity were surprisingly high for an insular species. Our data imply that the Azorean bat has a high conservation value. We argue that geographical patterns of genetic structuring indicate the existence of two management units. [ABSTRACT FROM AUTHOR]

Because of their role in limiting gene flow, geographical barriers like mountains or seas often coincide with intraspecific genetic discontinuities. Although the Strait of Gibraltar represents such a potential barrier for both plants and animals, few studies have been conducted on its impact on gene flow. Here we test this effect on a bat species (Myotis myotis) which is apparently distributed on both sides of the strait. Six colonies of 20 Myotis myotis each were sampled in southern Spain and northern Morocco along a linear transect of 1350 km. Results based on six nuclear microsatellite loci reveal no significant population structure within regions, but a complete isolation between bats sampled on each side of the strait. Variability at 600 bp of a mitochondrial gene (cytochrome b) confirms the existence of two genetically distinct and perfectly segregating clades, which diverged several million years ago. Despite the narrowness of the Gibraltar Strait (14 km), these molecular data suggest that neither males, nor females from either region have ever reproduced on the opposite side of the strait. Comparisons of molecular divergence with bats from a closely related species (M. blythii) suggest that the North African clade is possibly a distinct taxon warranting full species rank. We provisionally refer to it as Myotis cf punicus Felten 1977, but a definitive systematic understanding of the whole Mouse-eared bat species complex awaits further genetic sampling, especially in the Eastern Mediterranean areas. [ABSTRACT FROM AUTHOR]

Abstract: Recent studies have shown that species in the genus Myotis have evolved a number of convergent morphological traits, many of which are more related to their mode of food procurement than to their phylogeny. Surprisingly, the biogeographic origins of these species are a much better predictor of phylogenetic relationships, than their morphology. In particular, a monophyletic clade that includes all New World species was apparent, but only a third of the 38 species have been analysed. In order to better understand the evolution of this clade, we present phylogenetic reconstructions of 17 Nearctic and 13 Neotropical species of Myotis compared to a number of Old World congeners. These reconstructions are based on mitochondrial cytochrome b (1140bp), and nuclear Rag 2 genes (1148bp). Monophyly of the New World clade is strongly supported in all analyses. Two Palaearctic sister species, one from the west (M. brandtii) and one from the east (M. gracilis), are embedded within the New World clade, suggesting that they either moved across the Bering Strait, or that they descended from the same ancestor that reached the New World. An emerging feature of these phylogenetic reconstructions is that limited faunal exchanges have occurred, including between the North and South American continents, further emphasizing the importance of biogeography in the radiation of Myotis. A fossil-calibrated, relaxed molecular-clock model was used to estimate the divergence time of New World lineages to 12.2±2.0 MYA. Early diversification of New World Myotis coincides with the sharp global cooling of the Middle Miocene. Radiation of the temperate-adapted Myotis may have been triggered by these climatic changes. The relative paucity of species currently found in South America might result from a combination of factors including the early presence of competitors better adapted to tropical habitats. [Copyright &y& Elsevier]

• High prevalence of trypanosome infecting bat through the world. • Increase of phyletic diversity within each species of trypanosome. • Two new taxa of trypanosome discovered in the Miniopterus bat genus in Europe and Africa. • Multiple parasite infection in the Miniopterus bat genus. • Radiation of the T. cruzi clade from Africa through several dispersion events across the world. Understanding geographic patterns of interaction between hosts and parasites can provide useful insight into the evolutionary history of the organisms involved. However, poor taxon sampling often hinders meaningful phylogenetic descriptions of groups of parasites. Trypanosome parasites that constitute the Trypanosoma cruzi clade are worldwide distributed infecting several mammalian species, especially bats. Diversity in this clade has been recently expanded by newly discovered species, but the common ancestor and geographical origins of this group of blood parasites are still debated. We present here results based on the molecular characterization of trypanosome isolates obtained from 1493 bats representing 74 species and sampled over 16 countries across four continents. After estimating the appropriate number of hypothetical species in our data set using GMYC models in combination with Poisson Tree Processes (mPTP) and ABGD, the 18S rRNA and gGAPDH genes were used for phylogenetic analyses to infer the major evolutionary relationships in the T. cruzi clade. Then, biogeographical processes influencing the distribution of this cosmopolitan group of parasites was inferred using BioGeoBEARS. Results revealed a large lineages diversity and the presence of trypanosomes in all sampled regions which infected 344 individuals from 31 bat species. We found eight Trypanosoma species, including: five previously known; one subspecies of Trypanosoma livingstonei (Trypanosoma cf. livingstonei); and two undescribed taxa (Trypanosoma sp. 1, Trypanosoma sp. 2), which were found exclusively in bats of the genus Miniopterus from Europe and Africa. The new taxa discovered have both an unexpected position in the global phylogeny of the T. cruzi clade. Trypanosoma sp. 1 is a sister lineage of T. livingstonei which is located at the base of the tree, whereas Trypanosoma sp. 2 is a sister lineage of the Shizotrypanum subclade that contains T. c. cruzi and T. dionisii. Ancestral areas reconstruction provided evidence that trypanosomes of the T. cruzi clade have radiated from Africa through several dispersion events across the world. We discuss the impact of these findings on the biogeography and taxonomy of this important clade of parasites and question the role played by bats, especially those from the genus Miniopterus , on the dispersal of these protozoan parasites between continents. [ABSTRACT FROM AUTHOR]