Günther, A. (1903) - Reptiles from Rio de Oro, Western Sahara. - Novitates Zoologicae, London, 10: 298-299.   Harris, D.J. & Arnold, E.N. (2000) - Elucidation of the relationships of spiny-footed lizards, Acanthodactylus spp. (Reptilia: Lacertidae) using mitochondrial DNA sequence, with comments on their biogeography and evolution. - Journal of Zoology, London, 252 (3): 351-362.  × Mitochondrial DNA sequences consisting of 645 sites from the 12S rRNA and 16S rRNA genes were used to estimate the phylogeny of 15 of the 32 species of spiny-footed lizards Acanthodactylus. The resultant tree has similarities to that produced from a differentially weighted data set of 32 morphological characters but there are also significant differences. However, combined analysis of molecular and morphological data sets produces the same tree topology as DNA sequence alone. The molecular data confirm that there are distinct eastern and western clades within Acanthodactylus, but place A. boskianus in the former while the A. scutellatus group constitutes a third clade. Species for which only morphological information is available were integrated with the combined tree to give a provisional phylogeny for 31 species. This phylogeny indicates that the ancestor of existing Acanthodactylus probably originated in south-west Asia and that North Africa was invaded by more than one lineage of the genus. It also suggests that soft aeolian sand habitats may have been independently occupied more than once. Molecular data provide independent evidence that the differential weighting of morphological characters in past analyses was appropriate. Crochet, P.-A. & Geniez, P. & Ineich, I. (2003) - A multivariate analysis of the fringe-toed lizards of the Acanthodactylus scutellatus group (Squamata: Lacertidae) systematics and biogeographical implications. - Zoological Journal of the Linnean Society, 137 (1): 117-155. × The taxonomy of the fringe-toed lizards of the Acanthodactylus scutellatus group has long been unstable and no consensus exists on the systematic status of its various forms. A multivariate analysis of morphological characters, performed on over 1000 specimens from most of the African range of this group, allowed us to clarify the specific allocation of most of the Saharan populations included in this species group. Based on comparisons of morphology between allopatric and sympatric populations of this complex, we propose the recognition of six biological species. Our results confirm the specific status of Acanthodactylus aureus , A. dumerili , A. scutellatus, A. longipes and the recently described A. taghitensis . In addition, we re-validate A. senegalensis (occurring from Mauritania and Mali south to Senegal), which has been treated as a synonym of A. dumerili by previous authors. Acanthodactylus longipes is reported for the first time from coastal Mauritania, and A. taghitensis (previously known only from a very small region in Algeria) is reported from continental Mauritania. The systematic section of this paper includes a full list of examined material, diagnosis and known distribution of each species, in addition to some information on geographical variation and ecology. A key for specific identification is provided as an appendix. Tamar, K. & Carranza, S. & Sindaco, R. & Moravec, J. & Trape, J.-F. & Meiri, S. (2016) - Out of Africa: Phylogeny and biogeography of the widespread genus Acanthodactylus (Reptilia: Lacertidae). - Molecular Phylogenetics and Evolution, 103: 6-18. × Acanthodactylus lizards are among the most diverse and widespread diurnal reptiles in the arid regions spanning from North Africa across to western India. Acanthodactylus constitutes the most species-rich genus in the family Lacertidae, with over 40 recognized species inhabiting a wide variety of dry habitats. The genus has seldom undergone taxonomic revisions, and although there are a number of described species and species-groups, their boundaries as well as their interspecific relationships are largely unresolved. We constructed a multilocus phylogeny, combining data from two mitochondrial (12S, cytb) and three nuclear (MC1R, ACM4, c-mos) markers for 302 individuals belonging to 36 known species, providing the first large-scale time-calibrated molecular phylogeny of the genus. We evaluated phylogenetic relationships between and within species-groups, and assessed Acanthodactylus biogeography across its known range. Acanthodactylus cladogenesis is estimated to have originated in Africa due to vicariance and dispersal events from the Oligocene onwards. Radiation started with the separation into three clades: the Western and scutellatus clades largely distributed in North Africa, and the Eastern clade occurring mostly from Arabia to south-west Asia. Most Acanthodactylus species diverged during the Miocene, possibly as a result of regional geological instability and climatic changes. We support most of the current taxonomic classifications and phylogenetic relationships, and provide genetic validity for most species. We reveal a new distinct blanfordii species-group, suggest new phylogenetic positions (A. hardyi, A. masirae), and synonymize several species and subspecies (A. lineomaculatus, A. boskianus khattensis and A. b. nigeriensis) with their phylogenetically closely-related species. We recommend a thorough systematic revision of taxa exhibiting high levels of intraspecific variability as well as clear evidence of phylogenetic complexity such as A. guineensis, A. grandis, A. dumerilii, and A. senegalensis and the pardalis and erythrurus species-groups. Vicente Liz, A. & Rödder, D. & Vasconcelos Goncalves, D. & Velo-Antón, G. & Tarroso, P. & Geniez, P. & Crochet, P.-A. & Carvalho, S.B. & Brito, J.C. (2022) - Overlooked species diversity in the hyper-arid Sahara Desert unveiled by dryland-adapted lizards. - Journal of Biogeography. 2022; 00: 1-15. × Aim: Hyper-arid sandy and rocky fields rank among the least biologically diverse habitats of the desert biome, yet knowledge of local biodiversity patterns is also ex tremely poor. In the Sahara Desert, palaeoclimate oscillations affected the extent of hyper-arid habitats, but it is unclear how these dynamics determined the evolution and distribution of local specialists. Herein, we assessed cryptic diversity, diversification patterns and spatial connectivity within a Sahara-widespread group of dryland adapted lizards. Location: Sahara-Sahel ecoregions. Taxon: Acanthodactylus scutellatus species group. Methods: Inter- and intraspecific phylogenetic structure, divergence times, spatial genetic patterns and cryptic diversity were assessed using nuclear and mitochondrial loci. The effects of topography and land cover on phylogeographic structure and diversity were tested with generalized linear models. Interspecific hybridization was evaluated using 11 microsatellites across the group`s major sympatry zone, predicted based on ecological niche models. Results: Species of Acanthodactylus scutellatus group exhibit Late Miocene origins, followed by extensive intraspecific divergence throughout the Pliocene. The northern Sahara worked as a major diversification hotspot, harbouring a patchwork of small ranged, divergent lineages. These lineages are parapatric or sympatric and present concordant nuclear and mitochondrial differentiation, suggesting species status. Genetic connectivity increases in southern latitudes, with wide-ranging lineages spanning from the Red Sea to the Atlantic coast. Within these potential corridors, mountain outskirts and sand fields in the Sahara interior seemingly acted as origins for recent population expansions. Genetic diversity and connectivity are favoured by terrain roughness and soft-sand cover respectively. Three species inhabit the Atlantic Sahara sympatry zone without evidence of gene flow. Main conclusions: Overlooked species-level diversity within a major specialist group of Sahara drylands exposes the recurrent knowledge shortfalls present in hyper-arid desert environments. Humidity and sandy habitat shifts triggered potential successions of population isolation and re-connectivity, which favoured cladogenesis in northern desert regions and population expansions across southern east–west corridors.
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