Description:
<jats:p>The gecko genus<jats:italic> Phyllopezus </jats:italic>is distributed mainly along South America’s “Dry Diagonal” (Caatinga, Cerrado, and Chaco). The genus has been the subject of recent taxonomic analyses and includes four described species and seven candidate species referred to here as<jats:italic> Phyllopezus pollicaris </jats:italic>sensu lato. In Paraguay,<jats:italic> Phyllopezus </jats:italic>is known from the Chaco and Cerrado where it is abundant, and also from a small isolated population from a rocky hill formation named “Cordillera de Los Altos” (Los Altos mountain range). Here we analyzed genetic samples from across its range, including new samples from Paraguay, using DNA barcoding analysis of the mitochondrial 16S gene and phylogenetic analyses using both Bayesian and Maximum Likelihood methods. We found genetic and morphological differences among geckos from the Los Altos mountain range and the remaining<jats:italic> Phyllopezus </jats:italic>populations. Using both molecular and morphological evidence we describe a new<jats:italic> Phyllopezus</jats:italic> species, sister to<jats:italic> P. przewalskii</jats:italic>. Genetic differentiation among described and putative<jats:italic> Phyllopezus</jats:italic> species is greater than their morphological differences, which likely accounts for these cryptic taxa remaining undescribed for so long.</jats:p>