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Accueil du site → Master → Etats Unis → 2015 → Phylogeny and systematics of Panaspis and Afroablepharus skinks (Squamata : Scincidae) in the savannas of sub-Saharan Africa

University of Texas at El Paso (2015)

Phylogeny and systematics of Panaspis and Afroablepharus skinks (Squamata : Scincidae) in the savannas of sub-Saharan Africa

Medina, Maria Fernanda

Titre : Phylogeny and systematics of Panaspis and Afroablepharus skinks (Squamata : Scincidae) in the savannas of sub-Saharan Africa

Auteur : Medina, Maria Fernanda

Université de soutenance : UNIVERSITY OF TEXAS AT EL PASO

Grade : Master of Science (MS) 2015

Résumé
Snake-eyed skinks are relatively small lizards of the genera Panaspis and Afroablepharus. Along with closely-related scincid taxa, the allocation of these genera has been constantly rearranged based on morphology, ecology and biogeography. Members of these genera occur primarily in savanna habitats throughout sub-Saharan Africa and include species that have highly conserved morphology, which poses a challenge for taxonomic studies. We sequenced two mitochondrial (16S and cyt b) and two nuclear genes (PDC and RAG1 ) from 91 Panaspis and Afroablepharus samples from various localities in eastern, central and southern Africa. Concatenated gene-tree and divergence dating analyses were conducted to infer phylogenies and biogeographic patterns. Molecular data sets revealed several cryptic lineages, with most radiations occurring during the mid-Miocene to Pliocene. We infer that rifting processes (including the formation of the East African Rift System) and climatic oscillations contributed to the expansion of savannas and precipitated cladogenesis in snake-eyed skinks. Species in Panaspis and Afroablepharus used in this study formed a monophyletic group, rendering Afroablepharus as synonymous to Panaspis. As a result, species previously assigned to Afroablepharus must be allocated to Panaspis or a different genus. Divergence estimates and cryptic speciation patterns of snake-eyed skinks were consistent with previous studies of other savanna vertebrate lineages from the same areas examined in this study.

Mots clés : Systematic, Speciation, Evolution and Development, Divergence, Central africa, Lizard, Cryptic, Biological sciences, Biology

Présentation

Page publiée le 21 novembre 2015, mise à jour le 22 décembre 2017