Joger, U. & Mayer, W. (2002) - A new species of Mesalina from Abd al-Kuri, Socotra archipelago, Yemen, and a preliminary molecular phylogeny for the genus Mesalina. - Fauna of Saudi Arabia, 19: 497-505.  Vasconcelos, R. & Montero-Mendieta, S. & Simó-Riudalbas, M. & Sindaco, R. & Santos, X. & Fasola, M. & Llorente, G. & Razzetti, E. & Carranza, S. (2016) - Unexpectedly High Levels of Cryptic Diversity Uncovered by a Complete DNA Barcoding of Reptiles of the Socotra Archipelago. - PLoS ONE, 11 (3): e0149985.  × Few DNA barcoding studies of squamate reptiles have been conducted. Due to the significance of the Socotra Archipelago (a UNESCO Natural World Heritage site and a biodiversity hotspot) and the conservation interest of its reptile fauna (94% endemics), we performed the most comprehensive DNA barcoding study on an island group to date to test its applicability to specimen identification and species discovery. Reptiles constitute Socotra`s most important vertebrate fauna, yet their taxonomy remains under-studied. We successfully DNA-barcoded 380 individuals of all 31 presently recognized species. The specimen identification success rate is moderate to high, and almost all species presented local barcoding gaps. The unexpected high levels of intra-specific variability found within some species suggest cryptic diversity. Species richness may be under-estimated by 13.8-54.4%. This has implications in the species` ranges and conservation status that should be considered for conservation planning. Other phylogenetic studies using mitochondrial and nuclear markers are congruent with our results. We conclude that, despite its reduced length (663 base pairs), cytochrome c oxidase 1, COI, is very useful for specimen identification and for detecting intra-specific diversity, and has a good phylogenetic signal. We recommend DNA barcoding to be applied to other biodiversity hotspots for quickly and cost-efficiently flagging species discovery, preferentially incorporated into an integrative taxonomic framework. Simó-Riudalbas, K. & Tamar, K. & Smid, J. & Mitsi, P. & Sindaco, R. & Chirio, L. & Carranza, S. (2019) - Biogeography of Mesalina (Reptilia: Lacertidae), with special emphasis on the Mesalina adramitana group from Arabia and the Socotra Archipelago. - Molecular Phylogenetics and Evolution, 137: 300-312. × The lacertid lizards of the genus Mesalina inhabit the arid regions of the Old World, from North Africa to NW India. Of the 19 recognized species within the genus, eleven occur in Arabia. In this study, we explore the genetic variability and phylogeographic patterns of the less studied M. adramitana group from southern Arabia and the Socotra Archipelago within the phylogenetic and biogeographic context of the entire genus. Our unprecedented sampling extends the distribution ranges of most Mesalina species and, for the first time, sequences of M. ayunensis are included in a phylogenetic analysis. We perform analyses of concatenated multilocus datasets and species trees, conduct species delimitation analyses, and estimate divergence times within a biogeographic framework. Additionally, we inferred the environmental suitability and identified dispersal corridors through which gene flow is enabled within M. adramitana. Our results show that the Socotra Archipelago was colonized approximately 7 Mya by a single oversea colonization from mainland Arabia. Then, an intra-archipelago dispersal event that occurred approximately 5 Mya resulted in the speciation between M. balfouri, endemic to Socotra, Samha and Darsa Islands, and M. kuri, endemic to Abd al Kuri Island. Similar to previous studies, we uncovered high levels of genetic diversity within the M. adramitana species-group, with two highly divergent lineages of M. adramitana living in allopatry and adapted to locally specific climatic conditions that necessitate further investigation.
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