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Phylogeny and evolution of Tropidurus of the torquatus group (Squamata: Tropiduridae)

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Marco Aurélio de Sena
Total Authors: 1
Document type: Doctoral Thesis
Press: São Paulo.
Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
Defense date:
Examining board members:
Miguel Trefaut Urbano Rodrigues; Marcelo Rodrigues de Carvalho; Cristiano de Campos Nogueira; Katia Cristina Machado Pellegrino
Advisor: Miguel Trefaut Urbano Rodrigues

As presently understood, the Tropidurus torquatus group comprises 15 lizard species distributed in open areas throughout Cis-Andean South America. These species include saxicolous and psammophilous populations with uncertain phylogenetic relationships. The aim of this work was to provide a comprehensive phylogenetic analysis of the group based on two mitochondrial and three nuclear markers. Our sample represents the most extensive geographic coverage of the group\'s distribution, including the largest possible number of saxicolous and psammophilous populations. Our approach also involve a parallel morphological analysis based on meristic and morphometric data in order to delimit the taxonomic lineages. The phylogenetic analyses included 14 of the 15 species known to date, whereas morphological data were obtained from at least one individual of all nominal species. Our results recovered the genus Tropidurus as non-monophyletic; of the 14 species included in the molecular analyses T. erythrocephalus, T. hygomi, T. insulanus, T. montanus, T. mucujensis and T. psammonastes are monophyletic, whereas all other traditional taxa are apparently para/polyphyletic aggregates. The relationships between psammophilous and saxicolous populations are complex indicating least 10 independent origins of sandy lineages, as well as at least 10 candidate species without available names. Many of the traditional species previously considered widespread, and therefore of minor concern from conservation perspectives, (e.g., T. hispidus, T. oreadicus and T. torquatus) in fact consist of many microendemic lineages that should receive special conservational attention. (AU)