Variação morfológica e molecular de Typhlops reticulatus (Linnaeus, 1758) (Serpentes: Typhlopidae)

Abstract

Snakes are traditionally divided in two infraorders: Alethinophidia, taxonomic and ecologically more diverse and Scolecophidia, a group of fossorial snakes known as blindsnakes. Among Scolecophidia, Typhlopidae is the most specious family with 260 species. Due to the fossorial habitat, the Typhlopidae are poorly represented in scientific collections and the paucity of sample tissues has been an impediment to molecular studies. Therefore, many aspects of evolutionary biology including prevalent modes of speciation, patterns of diversification, and geographical structuring of population genetic diversity, are still poorly understood. The goals of this study are to analyze the morphological and molecular variation of Typhlops reticulatus, a fossorial snake. For the morphological analysis, 314 specimens of Typhlops (196 of Typhlops reticulatus). were used, morphometric, scalation, hemipenis and cranial osteology characters were analysed. We sequenced the mitochondrial genes Coi and Cyt b for 21 tissue samples of T. reticulatus from different localities. We used Maximum Parsimony and Maximum Likelihood to construct the phylogenetic trees and the relationships among the groups were infered through haplotype network. Through molecular and morphological characters, we detected two different evolutionary lineages of T. reticulatusAmazon River; the last described as a new species in this study. Our analysis also identified two new species: Typhlops sp nov. 1 collected in Urbano Santos, Maranhão and Typhlops sp nov. 2 from Manaus, Amazonas. The results of this study support the previous idea that species with wide geographic distributions conceal cryptic diversity and have evolutionary histories more complex than previewed.