The Herpetological Journal

Authors: Angela M. Mendoza-Henao, Juan Alejandro Guerrero-Cupacan, Khristian Venegas-Valencia & Mailyn A. Gonzalez

Abstract: Taxonomic and spatial biases limit the understanding of biodiversity patterns, particularly in the Neotropics, with consequences in systematics, biogeography and conservation. Here, we address the impact of these biases by focusing on the widespread species Trachycephalus typhonius. Despite its common occurrence across its range, misidentifications and cryptic diversity have obscured its true phylogenetic and biogeographic histories. Through extensive field sampling and molecular analysis of cis- and trans-Andean localities, we revealed substantial genetic divergence within T. typhonius, which suggests the presence of multiple cryptic species. The samples from Orinoquia (cis-Andes) and Magdalena Valley (trans-Andes) in Colombia, differ from T. typhonius sensu stricto in Guyana. At least three lineages were observed for T. typhonius across the continent, suggesting a complex diversification pattern shaped by major Neotropical barriers. Our results show the influence of both Andes and Amazon-Orinoquia on the phylogeographic structure and provide insights into the biogeographic history of T. typhonius sensu lato. We discuss the importance of addressing taxonomic and spatial biases, and highlight how geographic barriers and historical processes have influenced diversification in the Neotropics. Our findings illustrate the need for comprehensive sampling and molecular studies for ‘common’ species, to unravel hidden diversity, which is crucial for accurate biodiversity assessments, understanding evolutionary processes, refine biogeographic models, reassess species distributions and inform conservation strategies. Este resumen traducido al español está disponible en supplementary materials.

Keywords: cryptic diversity, Amazon, phylogeography, sampling biases, Neotropics