Termorregulación de dos poblaciones de lagartijas simpátridas: Sceloporus lineolateralis y Sceloporus poinsettii (Squamata: Phrynosomatidae) en Durango, México

ResumenLa temperatura ambiental es un factor importante en la regulación de la actividad y los procesos fisiológicos de los organismos ectotermos. Las especies que habitan en simpatría están expuestas a un nicho térmico similar y aquellas especies que están cercanamente emparentadas pueden presentar requerimientos térmicos similares. En el presente trabajo, se estudió la ecología térmica de 2 poblaciones de lagartijas vivíparas, Sceloporus lineolateralis y S. poinsettii, pertenecientes a los grupos Sceloporus torquatus y Sceloporus poinsettii, las cuales habitan en simpatría en la localidad de Peñón Blanco, Durango, México. Las temperaturas corporales de las lagartijas activas en campo y el intervalo de temperaturas corporales preferidas fueron similares entre ambas especies; sin embargo, S. poinsettii registró mayor eficiencia y precisión en la termorregulación, debido a que el intervalo de temperaturas preferidas de esta especie es más amplio. Finalmente, las preferencias térmicas fueron análogas a las registradas anteriormente para los grupos S. torquatus, S. poinsettii y para otras especies del género.AbstractEnvironmental temperature is an important factor that regulates activity and physiological processes of ectotherms. Because sympatric species are exposed to similar thermal niche conditions, closely related species could present similar thermal requirements. This similarity may generate interspecific competition for optimal thermal space. The thermal ecology of the sympatric viviparous lizards Sceloporus lineolateralis and S. poinsettii (Sceloporus torquatus and Sceloporus poinsettii groups, respectively) were studied in natural populations in Peñón Blanco, Durango, Mexico. We found that active body temperatures and selected body temperatures were similar among species. However, S. poinsettii exhibited higher efficiency and accuracy of thermoregulation because the preferred thermal range of this species was wider. Finally their thermal preferences are analogous to those previously reported for the both groups and the genus

The insular herpetofauna of Mexico: Composition, conservation, and biogeographic patterns

We compile a Mexican insular herpetofaunal checklist to estimate endemism, conservation status, island threats, net taxonomic turnover among six biogeographic provinces belonging to the Nearctic and Neotropical regions, and the relationships between island area and mainland distance versus species richness. We compile a checklist of insular herpetofaunal through performing a literature and collection review. We define the conservation status according to conservation Mexican law, the Red List of International Union for Conservation of Nature, and Environmental Vulnerability Scores. We determine threat percentages on islands according to the 11 major classes of threats to biodiversity. We estimate the net taxonomic turnover with beta diversity analysis between the Nearctic and Neotropical provinces. The Mexican insular herpetofauna is composed of 18 amphibian species, 204 species with 101 subspecies of reptiles, and 263 taxa in total. Endemism levels are 11.76% in amphibians, 53.57% in reptiles, and 27.91% being insular endemic taxa. Two conservation status systems classify the species at high extinction risk, while the remaining system suggests less concern. However, all systems indicate species lacking assessment. Human activities and exotic alien species are present on 60% of 131 islands. The taxonomic turnover value is high (0.89), with a clear herpetofaunal differentiation between the two biogeographic regions. The species–area and species–mainland distance relationships are positive. Insular herpetofauna faces a high percentage of threats, with the Neotropical provinces more heavily impacted. It is urgent to explore the remaining islands (3,079 islands) and better incorporate insular populations and species in ecological, evolutionary, and systematic studies. In the face of the biodiversity crisis, islands will play a leading role as a model to apply restoration and conservation strategies

A new locality for the rare Guerreran Centipede Snake, Tantilla coronadoi Hartweg, 1944 (Squamata, Colubridae), with comments on morphological variation

We record the third known specimen of Tantilla coronadoi Hartweg, 1944 from Guerrero, Mexico. Our new record extends this species’ distribution by 90 km and to a new Mexican biogeographic province (Balsas Basin). The morphological similarity between this and the two previously known specimens supports the validity of the taxon, and otherwise points to the possible presence of an undescribed taxon on the coast of Guerrero. Additional fieldwork yielding a larger series of this and other infrequently encountered species may enable a better understanding of their distribution, natural history, ecology, and conservation

First record of Tantilla flavilineata Smith & Burger, 1950 (Squamata, Colubridae) for Puebla, Mexico

We record Tantilla flavilineata Smith & Burger, 1950, for the first time in the state of Puebla, Mexico. It was previously considered endemic to a small region of the state of Oaxaca. With this record, we extend the known distribution 100 km north-northwestward in a straight line. We also provide scales counts and description of the coloration in life of a female specimen. The geographic distribution of T. flavilineata appears to be restricted to mid-elevations in various oak woodlands which have been limited in area by agriculture. More information on its natural history, ecology, and geographic distribution is needed to develop conservation strategies for this rare snake

Ampliación de la distribución y presencia de una colonia reproductiva de la guacamaya verde (Ara militaris) en el alto Balsas de Guerrero, México Range expansion and reproductive colony of the Military Macaw (Ara militaris) in the upper Balsas basin, Guerrero, México

Se registra una población y colonia reproductora de guacamaya verde (Ara militaris) en el alto Balsas de Guerrero. La colonia se ubica en el bosque tropical seco de la localidad de Papalutla, al margen del río Atoyac, en el extremo noreste del estado. A lo largo de 4 años de conteos (n= 20), se registró una abundancia de 22.7 ± 2.8 individuos. Este registro confirma que la guacamaya verde aún se reproduce en Guerrero y amplía en aproximadamente 100 km hacia el extremo noreste del estado su distribución conocida.<br>We report a new population of green macaw (Ara militaris) to the Mexican state of Guerrero. The colony is located besides the Atoyac River, in the dry tropical forest of Papalutla, in the far northeast corner of the state. Along 4 years of counts (n= 20), an abundance of 22.7 ± 2.8 individuals has been registered. This report is relevant because it is the first record of a resident colony of green macaw in the upper Balsas basin, extending its known distribution range to the northwestern limit of Guerrero

A new species of Charadrahyla (Anura: Hylidae) from the cloud forest of western Oaxaca, Mexico

Jiménez-Arcos, Víctor H., Calzada-Arciniega, Rafael Alejandro, Alfaro-Juantorena, Liz A., Vázquez-Reyes, Leopoldo D., Blair, Christopher, Parra-Olea, Gabriela (2019): A new species of Charadrahyla (Anura: Hylidae) from the cloud forest of western Oaxaca, Mexico. Zootaxa 4554 (2): 371-385, DOI: https://doi.org/10.11646/zootaxa.4554.2.