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The ensembles of beetles and the seasonal distribution of diversity attracted to carrion in an artificial forest result of the urbanization of the Protected Natural Area Sierra de Guadalupe in central Mexico was studied. Monthly samples were collected from June 2017 to May 2018 using four carrion traps type NTP-80. A total of 3,434 individuals belonging to 17 families and 58 species were collected, of which 13 were identified to the species level and 45 to morphospecies. The species estimators suggest that was registered between 77.3% (Chao 1) and 80.5% (ACE) of the species. The families Staphylinidae, Silphidae, Carabidae, Leiodidae, Histeridae and Nitidulidae grouped 95.8% of the total abundance and 67.2% of the species. The family Staphylinidae was the higher richness with 21 species, the remaining had less than five species, of which the family Silphidae was the most important with four species, and represented the necrophagous guilt which was the second most abundant making up 21% of all beetles collected after the predators (62%). The diversity was higher in rainy than in drought season, the faunistic similarity between seasons was low (J=0.37), with 32 species exclusive of rainy and four of drought season. In the area inhabit wide-ranging species adapted to perturbation conditions, an endemic species, and converge montane elements with species of semiarid environments, therefore, is important to maintain the connection of the artificial forest with the forest area in upper parts of the Sierra de Guadalupe, and conserve the fragments of xeric shrubland that are scarce in the basin of Mexican Valley, so as to mitigate the impact of the urbanization in the diversity of beetles associated to carrion. [ABSTRACT FROM AUTHOR]

To evaluate the effects of desert scrub habitat fragmentation on resident and migrant populations of Red-tailed Hawk and American Kestrel, we conducted monthly raptor road surveys during two years, 2008 and 2009, in natural desert scrub areas and in fragmented areas of Baja California Sur, México. We recorded 1,806 records of the two raptor species. The most common was the American Kestrel with 1,164 (64.4%) records (51% found in fragmented area, and 49% in natural area). The Redtailed Hawk accounted for 642 records (35.6%) (70% in fragmented areas, and 30% in natural areas). The relative abundance and density of Red-tailed Hawk in the spring and summer were similar between areas, but in the fall and winter the abundances and densities were much higher in fragmented areas. The abundance of American Kestrel was similar between areas in all seasons. Density was similar between areas in spring, summer and winter but it was higher in fragmented areas in the fall. The desert scrub of Baja California Sur and fragmented areas inside a cultivated agricultural matrix is an important habitat for migrant populations of both raptor species as indicated by the results of the fall and winter seasons. We discuss on the raptor species tolerance to habitat changes (threshold concept) as a function of their body size and habitat specialization (for nesting and foraging activities) and on the effects of fragmentation of desert scrub habitats on the abundance and density of the Red-tailed Hawk and American Kestrel in southern Baja California peninsula. [ABSTRACT FROM AUTHOR]

Development of historic vegetation growth curves for both grasslands and shrublands in Mexico becomes a real challenge due to lack of statistics. Remote sensing technology using satellites, allows obtaining a first approximation through vegetation indices (VI). The present study discusses an indirect parametric modeling of the biomass growth curve in individual pixels of both Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS), thus allowing their characterization using pre and post process algorithms. Results obtained through application of the algorithms discussed in the present paper, allow obtaining annual growth curves at 100 ha (AHVRR) and 6.25 ha (MODIS) scales that can be used in studies on climate change and on grassland/shrubland management in Mexico. [ABSTRACT FROM AUTHOR]

A study of the diversity of legumes in the northern part of the state of Nuevo León was undertaken. 38 genera, 94 species and 26 infraspecific taxa of legumes were recorded. The family Fabaceae comprises 18 genera and 42 species, Mimosaceae 10 and 30 and Caesalpiniaceae 10 and 22 respectivelly. The genera with highest number of species are Acacia (12), Dalea (10), Mimosa (6), Senna (5), Caesalpinia (4) and Bauhinia (4). Shrubby legumes are the most abundant in the zone, representing 47% (46 species); the herbaceous ones constitute 46% (45) and the arboreal ones comprise 7% (7). The highest number of taxa was recorded on semithorn shrubland (52) piedmont scrub (48), oak-pine forest (44), while the mezquite shrublands shelter the lowest number of species (23). [ABSTRACT FROM AUTHOR]

A review is made of the endemic plants following the Megacoahuila concept, that increases the state area for more than 100%. The region has climatic and physiographic variation that leads to the development of at least 13 main vegetation types, the desert shrubland being the dominant one. A total of 350 species and infraspecific taxa are listed, representing 11.2% of the total flora. The desert shrubland (matorrales micrófilo y rosetófilo) is the vegetation with the highest endemism and the Cuatro Cienegas basin the richest locality. The areas with highest endemism are suggested to be considered biotic reserves. [ABSTRACT FROM AUTHOR]

Ipomoea rzedowskii is described as a new species to science, from the Mexican states of Guanajuato, Hidalgo and Querétaro. This white flowered shrub grows in xerophilous shrublands on steep slopes east of Xichú and in the canyons of Estórax, Moctezuma and Tolimán rivers. This new taxon belongs to the series Arborescentes. [ABSTRACT FROM AUTHOR]