The herpetofauna of Veracruz, Mexico: composition, distribution, and conservation status

The herpetofauna of the state of Veracruz, Mexico, currently consists of 359 species, including 76 anurans, 45 caudates, one caecilian, one crocodylian, 217 squamates, and 19 turtles. The distribution of the herpetofaunal species are catalogued here among the four recognized physiographic regions in the state. The total number of species ranges from 179 in the Sierra de Los Tuxtlas to 236 in the Sierra Madre Oriental. The number of species shared among the four physiographic regions ranges from 100 between the Gulf Coastal Lowlands and the Transmexican Volcanic Belt, to 190 between the Sierra Madre Oriental and the Transmexican Volcanic Belt. A similarity dendrogram based on the Unweighted Pair Group Method with Arithmetic Averages (UPGMA) depicts two distinct clusters, one between the Sierra Madre Oriental and the Transmexican Volcanic Belt, and the other between the Gulf Coastal Lowlands and the Sierra de Los Tuxtlas. The former cluster refects two adjacent regions in highland environments that share a substantial number of herpetofaunal species, and the latter cluster shares a sizeable number of wide-ranging, generalist, lowland species found on the Atlantic and Pacifc versants of Mexico and Central America. The level of herpetofaunal endemism is relatively high, with 182 of 359 species either endemic to Mexico or to Veracruz. The distributional categorization of the total herpetofauna is as follows: 169 non-endemic species; 138 country endemic species; 44 state endemic species; and eight non-native species. The 169 non-endemic species are allocated to the following distributional categories: MXCA (89), MXSA (30), MXUS (29), USCA (11), USSA (four), and OCEA (fve). The principal environmental threats to the herpetofauna of Veracruz include deforestation, livestock, roads, water pollution, myths and other cultural factors, diseases, invasive species, and illegal commerce. The conservation status of each native species was evaluated using the SEMARNAT, IUCN, and EVS systems, of which the EVS system proved to be the most useful. The Relative Herpetofaunal Priority method was employed to determine the rank order signifcance of the four regions, and this identifed the Sierra Madre Oriental as the region of greatest importance. Only six protected areas exist in Veracruz, most of which are located in the Gulf Coastal Lowlands, the region of least conservation signifcance. The area of greatest signifcance, the Sierra Madre Oriental, does not contain any protected areas. A total of 265 species have been recorded within the six protected areas, of which 138 are non-endemics, 89 are country endemics, 31 are state endemics, and seven are non-natives. Finally, we provide a set of conclusions and recommendations to enhance the prospects for the future protection of the herpetofauna of Veracruz

An updated list of the Mexican herpetofauna: with a summary of historical and contemporary studies

The growth in our knowledge of the diversity of the herpetofauna of Mexico has occurred over the period of approximately 445 years from the work of Francisco Hernández to that of a broad multinational array of present-day herpetologists. The work of this huge group of people has established Mexico as one of the most significant centers of herpetofaunal biodiversity in the world. This status is the result of a complex orography, in addition to diverse habitats and environments and the biogeographic history of Mexico. The current herpetofauna consists of 1,421 native and introduced species, allocated to 220 genera, and 61 families. This figure is comprised of 1,405 native species and 16 non-native species (as of April 2023). The non-native species include two anurans, 13 squamates, and one turtle. The level of endemism is very high, presently lying at 63%, with this level expected to increase with time. Species richness varies among the 32 federal entities in the country, from a low of 50 in Tlaxcala to a high of 492 in Oaxaca. Amphibian species richness by state-level can be envisioned as comprising three levels of low, medium, and high, with the lowest levels occurring in the Peninsula of Baja California, a group of seven states in north-central and central Mexico, and a group of three states in the Yucatan Peninsula, with the highest levels occupying the southern states of Guerrero, Puebla, Veracruz, Oaxaca, and Chiapas, and the medium level in the remaining states of the country. Reptile species richness also can be allocated to three categories, with the lowest level occupying Baja California Sur, a group of central states, and the states of the Yucatan Peninsula, and the highest level found in a cluster of the states of Veracruz, Guerrero, Oaxaca, and Chiapas. Knowledge of the Mexican herpetofauna will continue to grow with additional studies on systematics, conservation, and the construction of checklists at various levels