How the African house gecko (Hemidactylus mabouia) conquered the world.

Alien species are among the greatest threats to biodiversity, but the evolutionary origins of invasiveness remain obscure. We conducted the first range-wide sampling of Hemidactylus mabouia from more than 120 localities across Africa, Madagascar and the Neotropics to understand the evolutionary history of one of the most widely distributed, invasive vertebrates in the world. We used a multi-locus phylogeny, species delimitation, fossil-calibrated timetree, ancestral area reconstruction and species distribution models (SDMs) to determine how many putative species-level lineages are contained within H. mabouia, the timing and tempo of diversification, and the origins of commensality-providing insights into the evolutionary origins of invasiveness. Our analyses suggest 'H. mabouia' originated in the Miocene in the Zambezian biogeographic region and includes as many as 20 putative species-level lineages, of which only Hemidactylus mabouia sensu stricto is invasive and widely distributed, including all Neotropical records. Zambezia is the hotspot for diversity within the group with 14 species in southeastern Zambezia. SDMs suggest that H. mabouia was able to establish in the Neotropics due to habitat suitability, and globalization and the slave trade probably allowed it to cross the Atlantic. Distribution models for the H. mabouia complex overpredict the range of the invasive H. mabouia sensu stricto-highlighting the importance of taxonomy in invasive species management.

Diversity, distribution and conservation of the terrestrial reptiles of Oman (Sauropsida, Squamata).

In the present work, we use an exceptional database including 5,359 records of 101 species of Oman's terrestrial reptiles together with spatial tools to infer the spatial patterns of species richness and endemicity, to infer the habitat preference of each species and to better define conservation priorities, with especial focus on the effectiveness of the protected areas in preserving this unique arid fauna. Our results indicate that the sampling effort is not only remarkable from a taxonomic point of view, with multiple observations for most species, but also for the spatial coverage achieved. The observations are distributed almost continuously across the two-dimensional climatic space of Oman defined by the mean annual temperature and the total annual precipitation and across the Principal Component Analysis (PCA) of the multivariate climatic space and are well represented within 17 out of the 20 climatic clusters grouping 10% of the explained climatic variance defined by PC1 and PC2. Species richness is highest in the Hajar and Dhofar Mountains, two of the most biodiverse areas of the Arabian Peninsula, and endemic species richness is greatest in the Jebel Akhdar, the highest part of the Hajar Mountains. Oman's 22 protected areas cover only 3.91% of the country, including within their limits 63.37% of terrestrial reptiles and 50% of all endemics. Our analyses show that large areas of the climatic space of Oman lie outside protected areas and that seven of the 20 climatic clusters are not protected at all. The results of the gap analysis indicate that most of the species are below the conservation target of 17% or even the less restrictive 12% of their total area within a protected area in order to be considered adequately protected. Therefore, an evaluation of the coverage of the current network of protected areas and the identification of priority protected areas for reptiles using reserve design algorithms are urgently needed. Our study also shows that more than half of the species are still pending of a definitive evaluation by the International Union for Conservation of Nature (IUCN).

Cryptic diversity in Ptyodactylus (Reptilia: Gekkonidae) from the northern Hajar Mountains of Oman and the United Arab Emirates uncovered by an integrative taxonomic approach.

The Hajar Mountains of south-eastern Arabia form an isolated massif surrounded by the sea to the east and by a large desert to the west. As a result of their old geological origin, geographical isolation, complex topography and local climate, these mountains provide an important refuge for endemic and relict species of plants and animals. With 19 species restricted to the Hajar Mountains, reptiles are the vertebrate group with the highest level of endemicity, becoming an excellent model for understanding the patterns and processes that generate and shape diversity in this arid mountain range. The geckos of the Ptyodactylus hasselquistii species complex are the largest geckos in Arabia and are found widely distributed across the Arabian Mountains, constituting a very important component of the reptile mountain fauna. Preliminary analyses suggested that their diversity in the Hajar Mountains may be higher than expected and that their systematics should be revised. In order to tackle these questions, we inferred a nearly complete calibrated phylogeny of the genus Ptyodactylus to identify the origin of the Hajar Mountains lineages using information from two mitochondrial and four nuclear genes. Genetic variability within the Hajar Mountains was further investigated using 68 specimens of Ptyodactylus from 46 localities distributed across the entire mountain range and sequenced for the same genes as above. The molecular phylogenies and morphological analyses as well as niche comparisons indicate the presence of two very old sister cryptic species living in allopatry: one restricted to the extreme northern Hajar Mountains and described as a new species herein; the other distributed across the rest of the Hajar Mountains that can be confidently assigned to the species P. orlovi. Similar to recent findings in the geckos of the genus Asaccus, the results of the present study uncover more hidden diversity in the northern Hajar Mountains and stress once again the importance of this unique mountain range as a hot spot of biodiversity and a priority focal point for reptile conservation in Arabia.

A single origin of extreme matrotrophy in African mabuyine skinks.

Most mammals and approximately 20% of squamates (lizards and snakes) are viviparous, whereas all crocodilians, birds and turtles are oviparous. Viviparity evolved greater than 100 times in squamates, including multiple times in Mabuyinae (Reptilia: Scincidae), making this group ideal for studying the evolution of nutritional patterns associated with viviparity. Previous studies suggest that extreme matrotrophy, the support of virtually all of embryonic development by maternal nutrients, evolved as many as three times in Mabuyinae: in Neotropical Mabuyinae (63 species), Eumecia (2 species; Africa) and Trachylepis ivensii (Africa). However, no explicit phylogenetic hypotheses exist for understanding the evolution of extreme matrotrophy. Using multilocus DNA data, we inferred a species tree for Mabuyinae that implies that T. ivensii (here assigned to the resurrected genus Lubuya) is sister to Eumecia, suggesting that extreme matrotrophy evolved only once in African mabuyine skinks.

Resolving the higher-order phylogenetic relationships of the circumtropical Mabuya group (Squamata: Scincidae): An out-of-Asia diversification.

Despite an abundance of phylogenetic studies focused on intrageneric relationships of members of the Mabuya group, the intergeneric relationships have remained difficult to resolve. The most-persistent unresolved regions of the phylogeny of the group include: (1) the placement of the Middle-Eastern Trachylepis with respect to the Afro-Malagasy Trachylepis and its taxonomic status; (2) the phylogenetic position of the Cape Verdean Chioninia within the larger Mabuya group; (3) support for the placement of Dasia with respect to the entire group; and (4) the phylogenetic placement of Eutropis novemcarinata with respect to other Eutropis and Dasia. In this study, we include representatives of all these taxa as well as African Eumecia and Neotropical Mabuya. We seek to address these phylogenetic and systematic issues by generating a well-resolved and supported phylogeny for the Mabuya group as a whole that can be used to develop a stable taxonomy and reconstruct the geographic patterns of diversification within the group. To meet these goals, we built a large multi-locus dataset of 11 markers (nine nuclear and two mitochondrial), and performed concatenated and species tree analyses to generate a well-supported phylogeny for the group. Statistical topology tests reject the monophyly of Middle-Eastern Trachylepis with Afro-Malagasy Trachylepis, and to reflect monophyly we place the Middle-Eastern species into a previously described genus, Heremites. Cape-Verdean Chioninia are resolved as the strongly supported sister-group to Afro-Malagasy Trachylepis. Monophyly of the Southeast-Asian genera, Eutropis and Dasia, is not supported, with a clade composed of Dasia+Eutropis novemcarinata more closely related to the rest of the Mabuya group than to the remaining Eutropis. The phylogenetic position of E. novemcarinata renders Eutropis polyphyletic, and we therefore describe and place E. novemcarinata into a new monotypic genus, Toenayar, to preserve monophyly among the genera. In light of these novel findings, we review and discuss the historical biogeography of the entire Mabuya group.

Species on the rocks: Systematics and biogeography of the rock-dwelling Ptyodactylus geckos (Squamata: Phyllodactylidae) in North Africa and Arabia.

The understanding of the diversity of species in the Palearctic and the processes that have generated it is still weak for large parts of the arid areas of North Africa and Arabia. Reptiles are among their most remarkable representatives, with numerous groups well adapted to the diverse environments. The Ptyodactylus geckos are a strictly rock-dwelling genus with homogeneous morphology distributed across mountain formations and rocky plateaus from the western African ranges in Mauritania and the Maghreb to the eastern tip of the Arabian Peninsula, with an isolated species in southern Pakistan. Here, we use a broad sampling of 378 specimens, two mitochondrial (12S and cytb) and four nuclear (c-mos, MC1R, ACM4, RAG2) markers in order to obtain the first time-calibrated molecular phylogeny of the genus and place its diversification in a temporal framework. The results reveal high levels of intraspecific variability, indicative of undescribed diversity, and they do not support the monophyly of one species (P. ragazzii). Ptyodactylus species are allopatric across most of their range, which may relate to their high preference for the same type of structural habitat. The onset of their diversification is estimated to have occurred in the Late Oligocene, while that of several deep clades in the phylogeny took place during the Late Miocene, a period when an increase in aridification in North Africa and Arabia initiated.

New species of Stenodactylus (Squamata: Gekkonidae) from the Sharqiyah Sands in northeastern Oman.

A new species of gecko of the genus Stenodactylus (Squamata: Gekkonidae) is described from the dune desert of Al Sharqiyah Sands in northeastern Oman. Stenodactylus sharqiyahensis sp. nov. is characterized morphologically by its small size, snout shape, webbing between fingers not very extended, relatively short limbs, and scalation. It is genetically distinct in the mitochondrial DNA and the nuclear MC1R gene from Stenodactylus arabicus to which it has previously been referred. The new species seems to have a restricted distribution confined to the Sharqiyah Sands, which remain isolated from other sand deserts in Arabia. In addition, the data presented herein confirm new locality records for Stenodactylus arabicus in the easternmost limit of its distribution range in western central Oman. 

Nomenclature of African species of the genus Stenodactylus (Squamata: Gekkonidae).

The statuses of proposed nomina of the North African species of the genus Stenodactylus have been revised based on the study of their original descriptions and the examination of their name-bearing types. Important nomenclatural actions proposed include the designation of a lectotype for the nomen Stenodactylus guttatus ensuring continuity of the prevailing usage of S. petrii, and the proposal of maintaining prevailing usage of Stenodactylus sthenodactylus by applying to the International Commission of Zoological Nomenclature to set aside the existing name-bearing type and replace it with a neotype corresponding with that usage.

Conquering the Sahara and Arabian deserts: systematics and biogeography of Stenodactylus geckos (Reptilia: Gekkonidae).

BACKGROUND: The evolutionary history of the biota of North Africa and Arabia is inextricably tied to the complex geological and climatic evolution that gave rise to the prevalent deserts of these areas. Reptiles constitute an exemplary group in the study of the arid environments with numerous well-adapted members, while recent studies using reptiles as models have unveiled interesting biogeographical and diversification patterns. In this study, we include 207 specimens belonging to all 12 recognized species of the genus Stenodactylus. Molecular phylogenies inferred using two mitochondrial (12S rRNA and 16S rRNA) and two nuclear (c-mos and RAG-2) markers are employed to obtain a robust time-calibrated phylogeny, as the base to investigate the inter- and intraspecific relationships and to elucidate the biogeographical history of Stenodactylus, a genus with a large distribution range including the arid and hyper-arid areas of North Africa and Arabia. RESULTS: The phylogenetic analyses of molecular data reveal the existence of three major clades within the genus Stenodactylus, which is supported by previous studies based on morphology. Estimated divergence times between clades and sub-clades are shown to correlate with major geological events of the region, the most important of which is the opening of the Red Sea, while climatic instability in the Miocene is hypothesized to have triggered diversification. High genetic variability is observed in some species, suggesting the existence of some undescribed species. The S. petrii - S. stenurus species complex is in need of a thorough taxonomic revision. New data is presented on the distribution of the sister species S. sthenodactylus and S. mauritanicus. CONCLUSIONS: The phylogenetic hypothesis for the genus Stenodactylus presented in this work permits the reconstruction of the biogeographical history of these common desert dwellers and confirms the importance of the opening of the Red Sea and the climatic oscillations of the Miocene as major factors in the diversification of the biota of North Africa and Arabia. Moreover, this study traces the evolution of this widely distributed and highly specialized group, investigates the patterns of its high intraspecific diversity and elucidates its systematics.