Occasional papers (Texas Tech University. Museum)最新文献

Bats are the second most speciose lineage of mammals with more than 1,300 recognized species. Overall, bats are extremely ecologically and morphologically diverse, making them of interest to a wide variety of biologists. Bats are also known reservoirs for an assortment of zoonotic diseases, including rabies, for which they are commonly tested if identified as sick, behaving abnormally, or in instances where there has been a significant human exposure. In these cases, proper identification of bat species is important to public health experts as it will inform future testing procedures and management practices, as well as broaden our understanding of rabies virus bat variant distributions and disease ecology. Despite the multiple disciplines interested in bats, no key has been developed which includes all species found within the United States. For this reason, a dichotomous key and bat identification guide, designed to differentiate bats to species level, has been developed. This document can be used by people with a variety of backgrounds to morphologically identify bats quickly and accurately using only a scale, a ruler, and attention to detail.

Few studies have reported didelphid communities of ≥10 species, and all of these have been from within the tropics sensu stricto of South America. Herein a community of 12 species of didelphids is described from a sub-tropical site in south-central South America. The Reserva Natural del Bosque Mbaracayú, in northeastern Paraguay, lies at the western margin of the Interior Atlantic Forest and the southwestern limit of the Cerrado, two important South American ecoregions. The rich didelphid community in this area likely results from the mosaic of habitats encountered at the distributional limits of these two ecoregions. Within the context of this mosaic, the species' habitat associations and vertical occupancy are discussed, as well as the reproductive patterns and population abundance variation of the more commonly encountered species. Three Monodelphis species were found in sympatry, all strictly terrestrial, along with Cryptonanus chacoensis. Marmosa paraguayana shared all habitats with Gracilinanus agilis, and both of these species primarily were arboreal. Although this natural reserve has been more extensively sampled than any other area in Paraguay, numerous questions remain unanswered regarding this rich didelphid community.

Nucleotide sequences from the mitochondrial DNA cytochrome-b gene were used to infer phylogenetic relationships and estimate genetic distances from 10 individuals of Melanomys caliginosus and to explore the hypothesis that this taxon is comprised of multiple species. Individuals of four geographic populations of M. caliginosus from Central America (Nicaragua and Costa Rica), Panama, Venezuela, and Ecuador, respectively, were included in this analysis. Topologies obtained from maximum parsimony and Bayesian inference analyses were identical and produced clades referable to each of the geographic populations. Genetic distances between any pair-wise comparisons of the four groups (except between Panamanian and Venezuelan samples) were comparable to values estimated from comparisons of sister species in the closely related genus Nectomys. Distances between samples from Panama and Venezuela were greater than those of samples within the Ecuadorian and Central American clades, but less than that between species of Nectomys. Based on results from the sequence data, it appears that all four of the populations should be elevated to species level; however, additional data are needed to resolve the nomenclature of the Panamanian and Venezuelan populations.