Livia León-Paniagua

Evolutionary diversification and speciation in rodents of the Mexican lowlands: the Peromyscus melanophrys species group.

Despite some studies of the species groups within the genus Peromyscus have been performed, both evolutionary relationships among species within groups and group composition have remained controversial. In this study, we address phylogenetic relationships among species in the Peromyscus melanophrys group (P. melanophrys, P. perfulvus, and P. mekisturus), using a molecular phylogenetic analysis. This analysis is the first to include the poorly known P. mekisturus. We conducted maximum likelihood and Bayesian inference analyses with the ND3, tRNA-Arginine, ND4L, and partial ND4 mitochondrial genes, and the GHR nuclear gene. We consistently recovered a P. melanophrys group that is monophyletic with respect to the set of outgroups. Also, we recovered two distinct clades within P. perfulvus and two within P. melanophrys, one of which contain P. mekisturus among other P. melanophrys, all with geographic consistency. According to our divergence time estimates, the P. melanophrys group diverged during the Pliocene and the main diversification events within the group occurred at the end of the Pliocene and through the Pleistocene.

Noteworthy Records of Mammals from the State of Queretaro, Mexico

context, male bobwhites seemed to seek out whistling posts where canopy coverage of brush within 30 m averaged about 20% and where visual screening from 12 to 20 dm aboveground averaged 20 to 40%. We suspect that males also selected for overhead cover at perch sites. The mean height of whistling posts exceeded the mean height of perch sites on both areas (Table 1). Also, 79% of vocalizing males (n = 61) had overhead cover at the perch site. Lastly, there was consistency between areas in height of perch site suggesting males prefer to display about 1.5-2.5 m aboveground. The pooled mean was 2.1 m (SE = 0.24).

A new species of Habromys (Rodentia : Neotominae) from Mexico

ABSTRACT A new mouse species in the genus Habromys, H. schmidlyi, from the Mexican states of Guerrero and Estado de México, is described. Closest affinities of the new species are with H. simulatus and H. chinanteco, although strong morphometric differentiation and ample geographic isolation are evident. Penis structure and the basic karyotype of the new species are described.

DISTRIBUTIONAL RECORDS FOR MAMMALS FROM CHIAPAS, MEXICO

Abstract New distributional mammal records are reported for Yaxchilán, Chiapas, Mexico, and Belize. Nicéforos large-eared bat Trinycteris nicefori (Chiroptera, Phyllostomidae) is documented for the first time for Mexico, providing the northwesternmost locality for the species. A new Belizean locality also is reported and constitutes the northernmost record. The dark Mexican shrew Cryptotis griseoventris (Soricomorpha, Soricidae) has been reported previously from the highlands from Chiapas, in coniferous forest at elevations above 2,100 m; its presence in the lowland Selva Lacandona (below 90 m) is surprising and raises questions about its specific identify. Further studies are warranted.

A new species of small-eared shrew (Mammalia, Eulipotyphla, Cryptotis) from the Lacandona rain forest, Mexico

Abstract The diversity and distribution of mammals in the American tropics remain incompletely known. We describe a new species of small-eared shrew (Soricidae, Cryptotis) from the Lacandona rain forest, Chiapas, southern Mexico. The new species is distinguished from other species of Cryptotis on the basis of a unique combination of pelage coloration, size, dental, cranial, postcranial, and external characters, and genetic distances. It appears most closely related to species in the Cryptotis nigrescens species group, which occurs from southern Mexico to montane regions of Colombia. This discovery is particularly remarkable because the new species is from a low-elevation habitat (approximately 90 m), whereas most shrews in the region are restricted to higher elevations, typically > 1,000 m. The only known locality for the new shrew is in one of the last areas in southern Mexico where relatively undisturbed tropical vegetation is still found. The type locality is protected by the Mexican government as part of the Yaxchilán Archaeological Site on the border between Mexico and Guatemala. Resumen La diversidad y distribución de las musarañas en el trópico americano son, aún, parcialmente conocidas. Aquí presentamos la descripción de una nueva especie de musaraña de orejas cortas (Soricidae, Cryptotis) con base en dos ejemplares de museo colectados en la selva Lacandona, Chiapas, en el sur de Mexico. La nueva especie se puede distinguir de otras especies del género por una combinación de características que incluye la coloración del pelaje, el tamaño, caracteres dentales, craneales, postcraneales y distancias genéticas. El nuevo taxón podría estar relacionado al grupo de especies Cryptotis nigrescens, cuyas especies habitan desde el sur de Mexico hasta las montañas de Colombia. El descubrimiento es particularmente notable ya que la especie nueva habita en tierras bajas (cerca de los 90 m), mientras que la mayoría de las especies en la región están restringidas a elevaciones mayores a los 1000 m. La única localidad para la nueva especie descrita se ubica en la selva Lacandona, una de las últimas áreas al sur de Mexico con vegetación tropical que permanecen sin alterar. La localidad tipo se encuentra en una zona protegida por el gobierno federal mexicano, ya que es parte de la Zona Arqueológica Yaxchilán, ubicada en la frontera entre Mexico y Guatemala.

Genetic and ecological processes promoting early diversification in the lowland Mesoamerican bat Sturnira parvidens (Chiroptera: Phyllostomidae)

With 22 species, Sturnira is the most speciose genus of frugivorous Neotropical bats. Sturnira parvidens inhabits lowland tropical areas from Mexico to Central America. The elevation of this taxon to species level was recent, and discrepancies with respect to its geographic limits and phylogenetic position continue to exist. In order to identify genetic and ecological processes likely involved in the diversification and current distribution of S. parvidens, we evaluated relationships, researched phylogeographic and demographic history, and tested the divergence/conservatism of the climatic niche of this bat. We used data from mitochondrial loci (cytochrome b and the hypervariable D-loop region I) and the nuclear recombination activating gene 1, in 173 samples of S. parvidens and 77 samples of related species. We performed Bayesian analyses to infer phylogenetic relationships and analyzed phylogeographic structure, genetic diversity, divergence times and historical demography. Sturnira bakeri is the sister group of S. parvidens, and inhabits Western Ecuador. The two species diverged c. 1.84Ma, and their distributions are disjunct and separated by Sturnira luisi. Within S. parvidens there are two haplogroups with nearly allopatric distributions that are limited to the Sierra Madre del Sur, on the Mexican Pacific Slope. The divergence time between haplogroups was c. 0.423Ma and we detected signals of demographic expansion. We also analyzed 526 occurrence data of S. parvidens to test for changes in environmental niche of this species. We detected signals of divergence of climatic niche, mainly in temperature and seasonality variables. Likely, both genetic and ecological processes have shaped the evolutionary history of S. parvidens. Despite many climatic fluctuations during the Pleistocene, only the most intense oscillations had an impact on these bats. In addition, ecological differentiation prevents admixture of genetic lineages that are in contact and lack apparent geographical barriers at the southern Sierra Madre del Sur. We concluded that speciation in Sturnira was promoted by this taxons ability to colonize new geographical and environmental spaces and form genetically structured groups when populations become isolated.

NEW WILDLIFE HOSTS OF Leptospira interrogans IN CAMPECHE, MEXICO

Leptospira interrogans has been identified to cause leptospirosis, a widespread zoonotic disease that has been identified in domestic and wild animals. This work analyzed kidneys from two species of wild rodents from the state of Campeche, Mexico. Analyses were made by PCR using specific primers for detection of Leptospira interrogans DNA. The rodent species that tested positive were Heteromys gaumeri and Ototylomys phyllotis, both of which are new hosts for the bacteria in Southeastern Mexico. These records provide new insights into the disease’s transmission that should be studied carefully in order to identify other potential host species, including humans, which are at risk of becoming infected if they are in contact with infected wildlife.

First Records of Jaguar (Panthera onca) from the State of Michoacán, Mexico

Abstract In May 2010, we documented the presence of jaguars (Panthera onca) in the state of Michoacán, Mexico, by means of six photographs obtained with camera traps and a skull collected in the field. The photographs show an adult female and a subadult cub. These records were from tropical semi-deciduous forest in a transitional area between the Sierra Madre del Sur and the Pacific Coast. These records constitute the first evidence of the jaguar in Michoacán. Additional research is needed to confirm whether the records correspond to a resident population of jaguar rather than to wandering individuals. Resumen En mayo del 2010, documentamos la presencia de jaguares (Panthera onca) en el estado de Michoacán, México, a través de seis fotografías obtenidas con trampas cámara y un cráneo encontrado en el campo. Las fotografías enseñan a una hembra adulta y una cría subadulta. Estos registros se encontraron del bosque tropical subcaducifolio en una zona transicional entre la Sierra Madre del Sur y costa del Pacífico. Estos registros constituyen la primera evidencia del jaguar en Michoacán. Se requiere investigación adicional para confirmar si los registros corresponden a una población de jaguares residentes o a individuos errantes.

Myobiid mites (Trombidiformes, Myobiidae) of the golden bat Mimon cozumelae from Mexico. Description of the male and tritonymph of Ioanella mimon and new records of Eudusbabekia mimon

Abstract The male and the tritonymph of Ioanella mimon are described for the first time parasitizing to Mimon cozumelae from Yucatan, Mexico. Male of Ioanella mimon is characterized by the presence of legs I with the tibia and tarsus fused forming a small complex devoided of apical claws, legs II–IV with two claws, setae vi at level of anterior end of genital plate, genital plate rounded with an anterior projection, all intercoxal setae short; while the tritonymph is characterized by the presence of legs I unequal; legs II–IV with 2-1-1 claws, and posterior region of dorsal idiosoma with 3 pairs of cylindrical and toothed setae. Additionally, we include new locality and host records for Eudusbabekia mimon which was also found on Mimon cozumelae. Both species were described originally in association with Mimon bennettii at Bartica, Guyana.

Variación entre Modelos de Circulación Global para reconstrucciones de distribuciones geográficas del Último Máximo Glacial: relevancia para la filogeografía

Delgado L.A. 2018. Landscape Heterogeneity and tree species diversity in a tropical forest. Development and validation of a methodological proposal. Ecosistemas 27(1): 105-115. Doi.: 10.7818/ECOS.1475 Many landscapes exist as unstable spatial-temporal mosaics where changes in patterns of biodiversity are affected by nature processes and the dynamic interaction between social and ecological factors. It is a consequence of the natural dynamics of socio-economic systems that regulate man-made tropical forests. However, a significant proportion of studies have made generalizations about the relative values of biodiversity, without taking into account the high levels of internal heterogeneity in the biophysical properties and land uses of each site. The purpose of this study is to propose and validate a methodology to delimit the heterogeneity of the landscape based on criteria that integrate the coupling of human-ecological systems such as: space-time dynamics of deforestation and fragmentation; complexity of the landscape structure; current and historical land use and biophysical variability. For this, the use of satellite images, landscape metrics, field work, documentary review and multivariate analysis were combined. The proposed methodology is intended to help guide the empirical delimitation of landscape heterogeneity as a prerequisite for the selection of similar landscapes and forest patches in studies of the diversity of tree species, in order to provide an opportunity to control the possible difficulties caused by variability in the proportion of forests, landscape configuration and successional states, in estimating its effects on forest richness and floristic composition.