Accelerated climate change represents a major threat to the health of the planet's biodiversity. Particularly, lizards of the genusXenosaurusmight be negatively affected by this phenomenon because several of its species have restricted distributions, low vagility, and preference for low temperatures. No study, however, has examined the climatic niche of the species of this genus and how their distribution might be influenced by different climate change scenarios. In this project, we used a maximum entropy approach to model the climatic niche of 10 species of the genusXenosaurusunder present and future suitable habitat, considering a climatic niche conservatism context. Therefore, we performed a similarity analysis of the climatic niche between each species of the genusXenosaurus. Our results suggest that a substantial decrease in suitable habitat for all species will occur by 2070. Among the most affected species,X. tzacualtipantecuswill not have suitable conditions according to its climatic niche requirements andX. phalaroanthereonwill lose 85.75% of its current suitable area. On the other hand, we found low values of conservatism of the climatic niche among species. Given the limited capacity of dispersion and the habitat specificity of these lizards, it seems unlikely that fast changes would occur in the distribution of these species facing climate change. The low conservatism in climatic niche we found inXenosaurussuggests that these species might have the capacity to adapt to the new environmental conditions originated by climate change.

The decrease of the habitat is one of the main factors that affect the survival of G. flavomarginatus. This study assesses the halophytic grasslands loss over a period of 30 years in the distribution area of the Bolson tortoise and the effects of climate change on the habitat suitability of these grasslands and its possible impact on this tortoise. Grassland loss was assessed by an analysis of symmetric differences and the habitat suitability model was carried out by the method of overlapping layers raster. Our results showed a grassland loss of 63.7%; however, our current habitat suitability model points out that much of the grassland loss has occurred where the environmental conditions are suitable. These results suggest that anthropic activity is a main factor in the habitat disturbance in the study area. Likewise, the models for years 2050 and 2070 under the criteria RCP 2.6, RCP 4.5, RCP 6.0, suggest that anthropic activity will continue be the main cause of the grassland loss. Therefore, considering the association between the Bolson tortoise and grassland halophyte Hilaria mutica, which comprises around 60% of its diet, the viability of the Bolson tortoise depends largely on strategies aimed at protecting the soil that allow the presence of this grassland. The decrease of the habitat is one of the main factors that affect the survival of G. flavomarginatus. This study assesses the halophytic grasslands loss over a period of 30 years in the distribution area of the Bolson tortoise and the effects of climate change on the habitat suitability of these grasslands and its possible impact on this tortoise. Grassland loss was assessed by an analysis of symmetric differences and the habitat suitability model was carried out by the method of overlapping layers raster. Our results showed a grassland loss of 63.7%; however, our current habitat suitability model points out that much of the grassland loss has occurred where the environmental conditions are suitable. These results suggest that anthropic activity is a main factor in the habitat disturbance in the study area. Likewise, the models for years 2050 and 2070 under the criteria RCP 2.6, RCP 4.5, RCP 6.0, suggest that anthropic activity will continue be the main cause of the grassland loss. Therefore, considering the association between the Bolson tortoise and grassland halophyte Hilaria mutica, which comprises around 60% of its diet, the viability of the Bolson tortoise depends largely on strategies aimed at protecting the soil that allow the presence of this grassland.

The industrial production and commercialization of distilled beverages from Sotol plants (Family: Asparagaceae, Subfamily: Zolinoideae and Genus: Dasylirion) has witnessed a steady growth in recent decades; this condition involves a greater use of the raw material that comes almost exclusively from natural populations, which could compromise the sustainability of the marginalized areas of Northern México. In the present work, habitat availability was evaluated for the presence and use of the species; Dasylirion wheeleri (S. Watson ex Rothr.), Dasylirion cedrosanum (Trelease), and Dasylirion durangense (Trelease) in México, considering different scenarios of climate change. For this purpose, we used the niche’s spatial analysis from a correlative approach. The results show that under the current climate, the species studied have a predominantly low habitat suitability in the central region of the Chihuahuan desert, with D. cedrosanum being the species with the lowest suitability. For the year 2050, a slight increase in the habitat suitability is expected only for D. durangense and D. wheeleri. This suggests that D. cedrosanum could be considered as the species with the greatest vulnerability to the possible climatic variations generated by global climate change. Likewise, the analysis of the results indicates that D. durangense is the one who has the greatest potential for use; however, it is necessary to consider that many of its populations may be climatically stressed and an inappropriate use could put them at risk.

It has frequently been reported that species with strong niche conservatism will not be able to adapt to new climatic conditions, so they must migrate or go extinct. We have evaluated the shifts in climatic niche occupation of the species Astrophytum coahuilense and its potential distribution in Mexico. We understand niche occupation as the geographic zones with available habitats and with the presence of the species. To assess shifts in climatic niche occupation, we used niche overlap analysis, while potential distribution modeling was performed based on the principle of maximum entropy. The results indicate that this species presents a limited amplitude in its climate niche. This restriction of the climatic niche of A. coahuilense limits its ability to colonize new geographical areas with different climatic environments. On the other hand, the potential distribution models obtained from the present study allow us to identify potential zones based on the climatic requirements of the species. This information is important to identify high priority areas for the conservation of A. coahuilense.

We describe two new species and a new record of stygobitic gastropods from small groundwater-fed springs in Candela, Coahuila, northern Mexico. Phreatomascogos garciasaucedoi n. sp. is described based on shell morphology and is the second species of this formerly monotypic genus. According to the current classification, we have transferred this genus to Cochliopidea. Phreatodrobia candelensis n. sp. is described, and represents the first record of the genus in Mexico extending its known range more than one hundred kilometers to the south. Also found with the new stygosnails was Coahuilix hubbsi Taylor, 1966, which was previously known only as an endemic species from the neighboring Cuatro Ciénegas valley. The reported new subterranean snails are restricted in their distributions to two small water sources only a few meters long which flow directly into a touristic zone with swimming pools and other recreation areas. Using NatureServe Ranking, both new species were assigned as critically imperiled. The very limited distribution and negative anthropogenic impacts within the sites should draw special conservation attention for the reported stygobionts.

Mexico has a wide diversity of ecosystems, among which are different types of forests that cover almost 33% of the country’s territory. One of the main characteristics of these ecosystems is that they host a great diversity of organisms, including arthropods, who play an important role within these natural systems. The research was carried out in 3 sites in Pueblo Nuevo, Durango from September 2017 to March 2018. Twenty pit-fall traps and 10 necrophagous traps were used, as well as direct on-site specimen collection. A total of 18 251 organisms were collected that belonged to 20 orders and 67 families, grouped in eight trophic guilds, of which the detritivores were the most widely represented, followed by the coprophagous and the predatory. In the state of Durango there is an information void regarding the functions these organisms perform in the forests, and therefore this research study has as its main objective to evaluate trophic guilds associated with a pine - oak forest. En el territorio mexicano se encuentra una amplia diversidad de ecosistemas, dentro de los cuales podemos mencionar diferentes tipos de bosques que ocupan casi 33% del territorio nacional. Una de las características principales de estos ecosistemas es que presentan una alta diversidad de organismos, entre ellos los artrópodos quienes juegan roles importantes dentro de dichos sistemas naturales. El trabajo se realizó en 3 sitios de Pueblo Nuevo, Durango, durante septiembre 2017-marzo 2018. Se utilizaron 20 trampas pit-fall y 10 trampas necrófagas, así como muestreos directos en suelo. Se colectaron un total de 18,251 organismos pertenecientes a 20 órdenes y 67 familias, agrupados en ocho gremios tróficos, siendo los detritívoros el mejor representado, seguido de los coprófagos y depredadores. En el estado de Durango, existe un vacío de información acerca de las funciones que estos organismos realizan en los bosques, de tal manera que el presente trabajo tiene como principal objetivo evaluar los gremios tróficos asociados a un bosque de pino-encino.