Amphibians and Reptiles of the Pacific Lowlands Biogeographic Province of Mexico: Diversity, Similarities, and Conservation

The Pacific Lowlands (PL) of Mexico hosts a rich diversity of amphibians and reptiles, comprising 326 native species (76 amphibians and 250 reptiles) across 45 families. This region is significant from a biodiversity standpoint, accounting for 23.3% of Mexico's total amphibian and reptile species, with 30 species being endemic to the PL. Notably, the PL ranks sixth in amphibian and reptile diversity among Mexico's fourteen biogeographic provinces. The species composition indicates a complex biogeographic relationship for the province, which shares the highest percentages of species with the neighboring Transition Zone provinces, while also acting as a vital corridor for species adapted to varied environmental conditions. Despite its diversity, 24 species in the PL are of conservation concern, highlighting threats from habitat loss, urbanization, and the impacts of introduced species in the province. Our findings underscore the ecological significance of the PL and the urgent need for conservation efforts to protect its unique biodiversity.