La distribución potencial del gran grisón, Galictis vittata, llega al centro y este de México, incluida la parte sur del estado de Tamaulipas. Sin embargo, no hay registros geográficos que confirmen este límite. El presente estudio documenta el primer registro del gran grisón fotografiado por trampas cámara en la Reserva de la Biosfera “El Cielo”, Tamaulipas, México. En el área de estudio se instalaron 26 trampas cámara que fueron programadas para obtener fotografías con la hora y fecha impresa. También se realizó un mapa en el que se integró la distribución potencial del grisón, los registros de ocurrencia publicados y los registros fotográficos de “El Cielo”. Una trampa cámara registró dos fotografías del gran grisón en la Reserva de la Biosfera “El Cielo”, dentro de un bosque de pino-encino conservado. Los dos registros representan el único avistamiento confirmado para el grisón en Tamaulipas, y están localizados a 64.4 km al noroeste de la distribución potencial estimada y a 186 km al norte del registro confirmado en el sur del estado de San Luis Potosí. Los registros de este estudio expanden tanto la distribución potencial como la distribución conocida del grisón hacia el noroeste y al norte, respectivamente, y también, aumentan el límite de elevación conocido en México de 1,500 a 1,790 m. La presencia del gran grisón en “El Cielo”, se debe probablemente a que este sitio tiene las condiciones de hábitat para que se pueda distribuir esta especie.

Although being one of the most elusive reptiles in Mexico, Beaded Lizards are also one of the most famous, due to some biological peculiarities as the presence of venom glands and its colorful aspect. In this paper we gathered scientific literature about one of the mythic species inhabiting our country to favor its protection through scientific knowledge divulgation. The literature show a significant amount of knowledge about this species, but also the need to investigate key aspects in order to ensure the conservation of beaded lizards; for example, habitat disturbances sensitivity and habitat requirements, beaded lizard-human interaction dynamics, medical applications and genetic variability. A pesar de ser uno de los reptiles más esquivos en México, el lagarto escorpión es al mismo tiempo uno de los más famosos debido a sus peculiaridades, como la presencia de glándulas de veneno y la apariencia sumamente llamativa. Se recopila la literatura publicada sobre uno de los reptiles míticos de nuestro país para fomentar su protección a través de la divulgación científica. La literatura muestra un avance significativo en el conocimiento del lagarto escorpión, pero también evidencia la necesidad de investigar aspectos clave para su conservación: sensibilidad a las perturbaciones ambientales y requerimientos de hábitat, dinámica de interacción con las personas, aplicaciones medicinales y variabilidad genética.

Linear infrastructures such as agricultural irrigation channels produce physical changes and negative impacts to habitats, wildlife populations, communities, and ecosystems. Open irrigation channels act as a pitfall for wildlife and can affect vertebrates of all sizes. Nonetheless, small channels have received relatively little attention by conservation biologists. The objective of this study was to analyze vertebrate species richness and mortality in relation to different sections of an irrigation channel system and the surrounding landscape characteristics. For two years, we conducted monthly surveys along an open-channel irrigation system to estimate its effect on vertebrates through records of dead and alive individuals. We examined the spatial relation of species richness and mortality with transects using a canonical correspondence analysis and chi-squared tests to determine possible variations in the different structures of the channel and seasonality. Further, a landscape diversity index was used to analyze the importance of surrounding habitat structure and composition on these parameters. Most vertebrates (61%) were found dead, small mammals and reptiles were the most affected. Our results indicate that mortality of small vertebrates varies depending on species, structures of the open-channel agricultural irrigation system (i.e., concrete channel and floodgates), seasonality (i.e., wet, and dry), and landscape heterogeneity (i.e., high, medium, and low landscape diversity). The open-channel irrigation system is a threat to populations of small vertebrates in anthropized landscapes, conservation efforts should be directed at protecting water bodies and restructuring the open-channel agricultural irrigation system to avoid mortality of species such as small rodents (M. mexicanus) and reptiles (C. triseriatus, B. imbricata, and Thamnophis spp.).

Human activities have caused several changes in biotic communities all over the world. Some species maintain viable populations in altered environments through different adaptations, however, knowledge in this regard is scarce for certain taxa, including reptiles. We analysed the detectability and habitat selection of the rattlesnake Crotalus triseriatus to contribute to our knowledge about how this species responds to anthropogenic landscape change. Rattlesnakes were monitored for two years in two anthropized landscapes using visual encounter surveys. We analysed detectability in relation to climatic factors and human activity, and habitat selection was analysed in native and non-native vegetation. Our study shows that detectability of C. triseriatus is differentially affected in anthropized landscapes; human activity may be determinant in landscapes such as agricultural fields, whilst climatic factors may be determinant in landscapes where people are less active such as the protected areas within urban parks. The analyses of habitat selection shows that native vegetation is crucial for the persistence of C. triseriatus in the studied landscapes. Several strategies may allow rattlesnakes to persist in different anthropized landscapes; nonetheless, native habitat remnants should be protected in anthropized areas to conserve wildlife.

The Baird's patch-nosed snake (Salvadora bairdi) is a non-venomous species endemic to Mexico, included in the official regulation Nom-059 under the category of special protection (Pr). This species has a relatively wide geographical distribution, which includes the Sierra Madre Occidental and the Transmexican Volcanic Belt. In this report, we present a new maximum length for this species based on an individual recorded in the State of Mexico. La culebra chata de Baird (Salvadora bairdi) es una especie no-venenosa endémica de México, incluida en la norma oficial Nom-059 bajo la categoría de protección especial (Pr). Esta especie presenta una distribución geográfica relativamente amplia, que incluye la Sierra Madre Occidental y la Faja Volcánica Transmexicana. En esta nota reportamos una nueva longitud máxima para esta especie a partir de un individuo registrado en el Estado de México.

We assessed the current and possible future predicted distributions of the Mexican narrow-mouthed toad, Amphibia, Microhylidae Hypopachus variolosus (Cope, 1866) across its range to evaluate vulnerability under global change. (2) Methods: We integrated 481 validated occurrence records across the species’ distribution range, including 120 records from Mexico, with bioclimatic and land-cover predictors to build ensemble ecological niche models. We additionally incorporated human footprint metrics to evaluate anthropogenic pressure and projected future habitat suitability under climate and land-use change scenarios. (3) Results: Models showed high performance (TSS > 0.80; AUC > 0.90), identifying temperature and precipitation extremes as main drivers. Suitable habitats extended across both coasts and revealed novel areas in central Mexico. The most suitable habitat occurred under low human pressure, although localized impacts were detected. Deforestation in the Yucatán Peninsula reduced tree cover despite high climatic suitability. Future projections for 2050 under RCP 8.5 indicated marked reductions in modeled high-suitability areas, particularly in central Mexico. (4) Conclusions: These findings indicate high vulnerability to climate and land-use change and support updating distribution limits, incorporating new regions into conservation planning, and reassessing threat status to promote long-term persistence.