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The Mexican free-tailed bat ( Tadarida brasiliensis ) is an abundant, widely distributed species in Mexico, except for most of the Yucatan peninsula. We studied the helminth fauna of T. b. mexicana at seven localities in the State of Zacatecas in order to advance the knowledge of helminth parasites of wild vertebrates in northern-central Mexico. Eighty-four bat specimens were examined for the presence of helminth parasites following standard procedures; helminths found were identified and infections were characterized. Of the specimens examined, 65.47 % were parasitized. The helminth fauna comprises five taxa: three digeneans ( Dicrocoelium rileyi , Ochoterenatrema labda , and Urotrema scabridum ); one cestode ( Vampirolepis sp.); and one nematode ( Tadaridanema delicatus ). We present a brief morphological description of Urotrema scabridum . D. rileyi was the most prevalent and abundant helminth species. The intestine was the habitat most parasitized, with four species. Indirect life cycles predominate, and are related to the insectivorous habits of this host. Further studies on this host-parasite system are necessary to contribute to population monitoring and conservation; biogeographic patterns of helminth parasites of bats should also be studied to explore their origins and evolution in the region. U. scabridum is reported for the first time from Zacatecas. All species are new locality records.

Genetic diversity is essential to the evolutionary and adaptive potential of a species. Several empirical genetic studies have highlighted the importance of considering both neutral and adaptive genetic variation when characterizing microevolutionary dynamics. Genes at the major histocompatibility complex (MHC) have become excellent models for researching adaptive variation and natural selection, because of the crucial role they play against pathogens. The Jamaican fruit bat, Artibeus jamaicensis, is one of the most common and well-studied Neotropical mammals and is characterized by generalist feeding habits, high dispersal capability, and abundant populations. Fifteen localities ofArtibeus jamaicensis were genetically assessed using ten neutral microsatellites and one expressed MHC class II locus (DRB) in order to detect footprints of balancing selection. Extensive polymorphism was found at both markers. Overall, 161 alleles were identified at DRB exon 2 gene, and 315 at microsatellites. The observed and expected heterozygosity averaged over all localities ( ±SD) was 0.756 ± 0.15 and 0.885 ± 0.11, respectively, with all localities in Hardy-Weinberg equilibrium. Pairwise genetic differentiation estimates were generally significant, but the overall differentiation was lower at DRB gene (Fst = 0.039) than at microsatellites (Fst = 0.154). We detected significant isolation by distance at microsatellite loci, but not at DRB exon 2 gene. STRUCTURE and BAPS analyses detected a population genetic structure made up of five defined clusters. Our results suggest that balancing selection has maintained the allele frequencies of DRB exon 2 gene across the distribution of A. jamaicensis in Mexico.

Bat acoustic libraries are important tools that assemble echolocation calls to allow the comparison and discrimination to confirm species identifications. The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country. It was assembled following a standardized recording protocol that aimed to cover different recording habitats, recording techniques, and call variation inherent to individuals. The Sonozotz project included 69 species of echolocating bats, a high species richness that represents 50% of bat species found in the country. We include recommendations on how the database can be used and how the sampling methods can be potentially replicated in countries with similar environmental and geographic conditions. To our knowledge, this represents the most exhaustive effort to date to document and compile the diversity of bat echolocation calls for a megadiverse country. This database will be useful to address a range of ecological questions including the effects of anthropogenic activities on bat communities through the analysis of bat sound., The Sonozotz project represents the first nation‐wide library of bat echolocation calls for a megadiverse country.

The black bear Ursus americanus is one of the largest terrestrial carnivores that has a wide distribution in northeastern Mexico, the only country in which black bears are listed as endangered. We used 10 nuclear microsatellite loci to evaluate black bear genetic variability in 6 disjointed populations from northeastern Mexico. Non-invasive genetic techniques were applied to fecal and hair samples. Using a panel of 10 polymorphic microsatellites we identified 64 indi- viduals. Black bears showed low to moderate levels of genetic diversity in all sampled populations (mean ± SD expected heterozygosity, He = 0.63 ± 0.628). Pairwise comparisons between all 6 pop- ulations (φST = 0.315, p < 0.05) detected significant genetic differentiation between the western Coahuila and the northeastern Nuevo Leon regions, suggesting that black bears have low levels of gene flow between these 2 regions. Microsatellites revealed significant structure within the complex of disjoint areas in the region. The inbreeding coefficient was also significant (φIS = 0.143). The largest proportion of genetic variation (82.7%) was found between individuals within populations. Distance and anthropogenic activities may serve to limit gene exchange among pop- ulations which form at least 3 distinct genetic clusters; these may respond differently to environ- mental changes and should be considered distinct management units.

Early in the plant defense response against pathogens, transcription of specific genes is activated. We studied the genes up-regulated in the early resistance reaction of Phaseolus vulgaris against Colletotrichum lindemuthianum. The effect of the light–dark transition, ultraviolet-(A–B) light, and temperature stress on these genes was also evaluated. A calcium-binding protein and previously identified SUMO genes were over-expressed in the plant reaction to pathogen and under environmental stress. These genes appear to act as integrative signals and convergence points in early plant responses to pathogens and several forms of environmental stress. The calcium-binding protein gene was present in both plant and fungi genomes.

The White nosed coati (Nasua narica) it is a highly social carnivore inhabiting mainly Neotropical forests playing an important ecological role. A technique based on 454 sequencing of a library highly enriched for microsatellite repeats was used to develop loci for Nasua narica. Twenty-four polymorphic microsatellites were developed and tested as markers in the target species. All markers were genotyped on 18 different individuals from three distinct locations. We observed medium to low genetic variation across most loci (mean number of alleles per locus = 5). Levels of expected heterozygosity across all markers was fairly low (mean HE = 0.326, range 0.05–0.49).