Phylogeny, taxonomy and distribution of the Neotropical lizard genus Echinosaura (Squamata: Gymnophthalmidae), with the recognition of two new genera in Cercosaurinae

Abstract

The family Gymnophthalmidae is a highly diverse Neotropical lizard clade. Although multiple phylogenetic and taxonomic studies have reshaped our understanding of gymnophthalmid systematics and diversity, many groups remain understudied. This is the case for the cercosaurine genus Echinosaura, which includes eight species of small riparian lizards distributed across lower Central America and northern South America. Here, we present a comprehensive phylogenetic analysis of Echinosaura, including DNA data for all species of the genus for the first time. To rigorously test the relationships of all Echinosaura, we have assembled the largest molecular dataset of cercosaurine lizards to date. Our analysis refutes the monophyly of Echinosaura, with E. apodema and E. sulcarostrum not closely related to the remaining species. To remedy the polyphyly of Echinosaura, we describe two new genera for E. apodema and E. sulcarostrum. Morphological distinctiveness and biogeography further support these taxonomic changes. In light of our phylogenetic results, we review the species-level taxonomy of the redefined Echinosaura based on morphological and genetic variation. We resurrect E. centralis and designate a neotype given the absence of type and topotypic material. In addition, we provide taxonomic accounts for each species and analyse their patterns of geographic distribution.