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The appreciation of cryptic biological diversity, and the pace at which it is recognized, has greatly increased with the use of molecular systematic techniques. The gekkonid genus Cyrtodactylus Gray, 1827 is one example of a group that has undergone a particularly rapid increase in recognized diversity due to molecular systematic studies. Many of these new species result from recognizing closely related but diagnosable lineages into sister taxa. Our study implements a multi‐faceted approach to delimit cryptic Cyrtodactylus lineages on the Southeast Asian island of Borneo using morphological, ecological, and multilocus genetic data. We use multiple species delimitation models to assess species boundaries and identify clades that warrant further investigation. Unlike most morphologically cryptic species that have recently diverged, we find evidence of cryptic lineages being polyphyletic. Using multivariate statistical analyses, we show minimal phenotypic distinction between putative cryptic species within the C. pubisulcus complex. Despite not finding morphologically diagnostic characters, we demonstrate strong evidence for the specific recognition of C. hantu sp. nov. and C. miriensis sp. nov., which are currently considered conspecific with C. pubisulcus, from Sarawak, Malaysia. Our new concept for C. pubisulcus restricts the geographic range of the species to specific regions in western Sarawak, Malaysia, thus underscoring the need to conserve the limited remaining habitats of these species, as well as the considerable undescribed diversity across Borneo. [ABSTRACT FROM AUTHOR]

Aim New Caledonia is a remnant of the land mass Tasmantis that harbours high levels of endemism. Two primary hypotheses have been proposed for the origin of such endemic lineages; the first suggests a vicariant origin arising from the sundering of eastern Gondwana in the Cretaceous. The second posits more recent dispersal and colonization. We use concatenated and coalescent time-calibrated phylogenies to test whether New Caledonian diplodactylid geckos diversified steadily following an ancient vicariance event or experienced an early burst of diversification followed by a decline in net diversification after long-distance dispersal. Location New Caledonia, Gondwana. Methods Phylogenetic relationships were elucidated from a multilocus DNA data set. Divergence times were inferred using relaxed clock Bayesian methods on the concatenated data set and in a multispecies coalescent framework using * beast. In order to elucidate patterns of diversification for the New Caledonian clade we tested models of diversification using laser and ddd. Results The divergence of the New Caledonian clade from its Australian sister clade occurred well after Gondwanan fragmentation, and the age of the crown clade is younger than the proposed drowning period of the island. Diversification analyses strongly suggest that the group experienced an early burst of diversification, which has slowed towards the present. Main conclusions We demonstrate that the species-rich diplodactylid geckos endemic to New Caledonia are of recent origin and that the diversification of the clade is consistent with the expectations of a recent radiation. Diversification in this clade does not conform to a constant-rate model, but rather experienced an initial burst followed by a decline in net diversification. This pattern is consistent with a decline in diversification as ecological niche space was filled. Our results add to the growing body of evidence that recent adaptive radiations have contributed to the remarkable endemism of New Caledonia. [ABSTRACT FROM AUTHOR]

We sampled Palaearctic naked-toed geckos from across their range in India and used two mitochondrial and two nuclear genes to reconstruct relationships within a global phylogeny. Published sequences of Peninsular Indian Hemidactylus allow us to contrast these two groups in dating analyses - providing insights into the history of the Indian dry zone. Palaearctic naked-toed geckos first moved onto the Indian Plate in the Oligocene, with higher-level diversification probably linked to collision of the Indian and Eurasian plates, and subsequent dispersal into- India and diversification with increasing Miocene aridity. An independent gekkonid radiation with species in the dry zone, Hemidactylus diversified during the same period in Peninsular India. Our results demonstrate that dry zone taxa across India may date back to at least the Miocene, with a potential historical climatic barrier between the Indus and Peninsular Indian Divisions. ' Cyrtopodion' aravallense is revealed to be a complex with seven genetically and environmentally divergent lineages that began diversifying in the late Miocene, congruent with increased aridity in north-western India. This discovery of cryptic diversity in the Indian dry zone represents the first terrestrial vertebrate radiation from north-western central India and highlights how little we understand of the regions' biodiversity, emphasizing the need for systematic geographic sampling and multiline evidence to reveal true patterns of diversity. The ancestor of 'Cyrtopodion' aravallense came into the nascent Indian dry zone in the Miocene and has since diversified, potentially in the absence of any sympatric scansorial rupicolous geckos. Cyrtopodion scabrum represents a unique case of commensalism and shows phylogeographic structure in its presumed native range. The taxonomic implications of our study include a number of undescribed species, recognition of ' Cyrtopodion' as a distinct lineage and the non-monophyly of Altiphylax. [ABSTRACT FROM AUTHOR]

Heinicke, M. P., Greenbaum, E., Jackman, T. R. & Bauer, A. M. Phylogeny of a trans-Wallacean radiation (Squamata, Gekkonidae, Gehyra) supports a single early colonization of Australia. - Zoologica Scripta, 40, 584-602. The genus Gehyra (34 species) is rare among squamate reptile radiations in spanning continents, extending from southeast Asia to Australia and Polynesia. Among the family Gekkonidae sensu stricto, Gehyra is the only genus that is species rich in Australia. We performed molecular phylogenetic, divergence timing, and ancestral area analyses to investigate the evolutionary and biogeographic history of Gehyra. Phylogenetic analyses resolve Hemiphyllodactylus as the closest relative of Gehyra. Some data also link Perochirus to this group, but previously suggested relationships with other morphologically similar genera of geckos are not supported. Within Gehyra, three geographically discrete clades are recovered, respectively, concentrated in Asia, the Pacific islands and Australia. Ancestral area analyses suggest that Gehyra originated in Asia, with a single colonization of Australia occurring in the mid-Cenozoic. This date places the time of Gehyra colonization prior to those of other Australian gekkonid geckos, but after the near-endemic pygopodoid geckos, a Gondwanan relictual group. Based on these dates, times of origin may best explain relative differences in species diversity among Australian gekkotans. In contrast, although originating earlier, Gehyra is less diverse in Asia than in Australia. This pattern may be explained by the long-term presence of many competing, ecologically similar genera in Asia (e.g. Gekko, Hemidactylus, Lepidodactylus), whereas nearly all pygopodoids in Australia (the only gekkotans present at the time of colonization of Australia by Gehyra) are ecologically distinct. [ABSTRACT FROM AUTHOR]

Phylogeographic patterns in wide-ranging species in southern Africa remain largely unexplored, especially in areas north of South Africa. Here, we investigate population structuring, demographic history, and the colonization pattern of the western rock skink ( Trachylepis sulcata), a rock-dwelling species with a range extending from southwestern South Africa into Angola. Using 1056 bp from the mitochondrial marker ND2 and > 2.5 kb from three nuclear genes ( EXPH5, KIF24, RAG-1), we constructed allele networks, generated extended Bayesian skyline plots and performed population clustering analyses. Analyses of historical demographic patterns show an overall southward range expansion from Northern Namibia into Southern Namibia and South Africa, although we find contrasting genetic breaks across these geographic regions using nuclear and mitochondrial data. We suggest that mtDNA has introgressed across a nuclear break corresponding to the Knersvlakte region of South Africa, a previously proposed biogeographic barrier for rupicolous species. This pattern of mitochondrial variation contrasts sharply to that of other South African taxa previously investigated, which all show significant mtDNA differentiation across the Knersvlakte region. Additionally, while other taxa show divergences dating to the Pliocene, T. sulcata appears to be a recent arrival in southern Africa, having crossed this barrier and colonized South Africa in the mid-Pleistocene. The complex phylogeographic history of T. sulcata corroborates the intricate patterns of genetic variation found in South African taxa and provides novel insight into historical processes affecting species distributed across Namibia. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships among gekkotan lizards were estimated from five nuclear protein-coding genes in separate and combined analyses using maximum parsimony, maximum likelihood and Bayesian analyses. All analyses recovered a monophyletic trans-Atlantic gecko clade (Phyllodactylidae) consisting of the genera Asaccus, Haemodracon, Homonota, Phyllodactylus, Phyllopezus, Ptyodactylus, Tarentola and Thecadactylus. No other phylogenetic or taxonomic hypotheses have proposed linking these genera, which have been consistently grouped with other taxa outside of the clade. In this paper, we determine the relationships of this new clade to other major gekkotan groups, evaluate previous phylogenetic hypotheses regarding constituent members of this novel clade, and critically examine the use of historically important morphological characters in gekkotan systematics as they relate to this novel clade, specifically — phalangeal formulae, hyoid morphology and external structure of the toe-pads. [ABSTRACT FROM AUTHOR]

Aim Geckos (Reptilia: Squamata), due to their great age and global distribution, are excellent candidates to test hypotheses of Gondwanan vicariance against post-Gondwanan dispersal. Our aims are: to generate a phylogeny of the sphaerodactyl geckos and their closest relatives; evaluate previous phylogenetic hypotheses of the sphaerodactyl geckos with regard to the other major gecko lineages; and to use divergence date estimates to inform a biogeographical scenario regarding Gondwanan relationships and assess the roles of vicariance and dispersal in shaping the current distributions of the New World sphaerodactyl geckos and their closest Old World relatives. Location Africa, Asia, Europe, South America, Atlantic Ocean. Methods We used parsimony and partitioned Bayesian methods to analyse data from five nuclear genes to generate a phylogeny for the New World sphaerodactyl geckos and their close Old World relatives. We used dispersal–vicariance analysis to determine ancestral area relationships among clades, and divergence times were estimated from the phylogeny using nonparametric rate smoothing. Results We recovered a monophyletic group containing the New World sphaerodactyl genera, Coleodactylus, Gonatodes, Lepidoblepharis, Pseudogonatodes and Sphaerodactylus, and the Old World Gekkotan genera Aristelliger, Euleptes, Quedenfeldtia, Pristurus, Saurodactylus and Teratoscincus. The dispersal–vicariance analysis indicated that the ancestral area for this clade was North Africa and surrounding regions. The divergence between the New World spaherodactyl geckos and their closest Old World relative was estimated to have occurred c. 96 Myrbp. Main conclusions Here we provide the first molecular genetic phylogenetic hypothesis of the New World sphaerodactyl geckos and their closest Old World relatives. A combination of divergence date estimates and dispersal–vicariance analysis informed a biogeographical scenario indicating that the split between the sphaerodactyl geckos and their African relatives coincided with the Africa/South America split and the opening of the Atlantic Ocean. We resurrect the family name Sphaerodactylidae to represent the expanded sphaerodactyl clade. [ABSTRACT FROM AUTHOR]