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A new species of Eremias has been described from the Cholistan Desert of Pakistan. It constitutes the first record of the genus Eremias from the Oriental (Indian) region. The species has been named Eremias cholistanica, after the Cholistan Desert of Pakistan. This striped desert lacerta is not only different from all its congeners in several morphological characteristics but has been collected from an area distant from the previous known range of Eremias.

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Present studies are aimed to document the herpetofauna of Cholistan Desert and study its ecology. During the last three years from 2001 to 2003, attempts have been made to collect and observe the amphibians and reptiles in different parts of Cholistan Desert. More than four thousand specimens belonging to 44 species have so far been collected/observed from the study area. Among different collecting techniques adopted for these studies, “Pit-fall” traps and “Hand Picking” showed best results. The voucher specimens have been catalogued and are presently lying with Pakistan Museum of Natural History, Islamabad.

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Eremias Fitzinger, 1834 is a speciose Eurasian genus of true lizards with approximately 40 species. Eremias species occurring in Pakistan have never been examined before using molecular genetics. In the present study, six out of seven morphologically defined taxa distributed in Pakistan (E. acutirostris, E. aporosceles, E. cholistanica, E. kakari, E. persica, and E. scripta) were studied using mitochondrial (16S rRNA, cytochrome c oxidase subunit I, cytochrome b) and nuclear (Rag1) genes. Data of 29 individuals were included in phylogenies using ENA/GenBank sequences. With a maximum of 20 species per analyzed data set, this study represents the most complete phylogeny of the genus to date. Maximum Likelihood and Bayesian analyses were run for concatenated (3,528 bp) and single-locus data sets and supported by uncorrected p distance calculations to evaluate the phylogenetic placement and divergence of Pakistani taxa. Among the Pakistani taxa, we detected six mostly well-supported and deeply divergent clades (A-F) differing by uncorrected p distances of up to 23.8% for mtDNA (cytb) and 3.3% for the nuclear Rag1 locus. Despite morphological differences between E. aporosceles and E. acutirostris (both clade A), no unambiguous genetic support was found for these two taxa. Therefore, we regard E. aporosceles as a synonym of E. acutirostris. On the other hand, E. persica was found to represent a species complex with deeply diverged clades (E and F) in Pakistan. Eremias cholistanica (clade D) and E. kakari (clade B), two morphologically defined endemic taxa of Pakistan, were revealed as phylogenetically clearly distinct. Eremias scripta (clade C) from Pakistan was found to be genetically deeply divergent compared to sequences of this taxon from Afghanistan and Uzbekistan. Our study provides evidence that the current taxonomy of Eremias does neither reflect the genetic diversity nor the evolutionary history of the genus, necessitating a comprehensive integrative taxonomic revision of the whole genus.

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Aim: Small geographic ranges make species especially prone to extinction from an- thropogenic disturbances or natural stochastic events. We assemble and analyse a comprehensive dataset of all the world’s lizard species and identify the species with the smallest ranges—those known only from their type localities. We compare them to wide-ranging species to infer whether specific geographic regions or biological traits predispose species to have small ranges. Location: Global. Methods: We extensively surveyed museum collections, the primary literature and our own field records to identify all the species of lizards with a maximum linear geo- graphic extent of <10 km. We compared their biogeography, key biological traits and threat status to those of all other lizards. Results: One in seven lizards (927 of the 6,568 currently recognized species) are known only from their type localities. These include 213 species known only from a single specimen. Compared to more wide-ranging taxa, they mostly inhabit relatively inaccessible regions at lower, mostly tropical, latitudes. Surprisingly, we found that burrowing lifestyle is a relatively unimportant driver of small range size. Geckos are especially prone to having tiny ranges, and skinks dominate lists of such species not seen for over 50 years, as well as of species known only from their holotype. Two- thirds of these species have no IUCN assessments, and at least 20 are extinct. Main conclusions: Fourteen per cent of lizard diversity is restricted to a single location, often in inaccessible regions. These species are elusive, usually poorly known and little studied. Many face severe extinction risk, but current knowledge is inadequate to properly assess this for all of them. We recommend that such species become the focus of taxonomic, ecological and survey efforts.