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The distributions of amphibians, birds and mammals have underpinned global and local conservation priorities, and have been fundamental to our understanding of the determinants of global biodiversity. In contrast, the global distributions of reptiles, representing a third of terrestrial vertebrate diversity, have been unavailable. This prevented the incorporation of reptiles into conservation planning and biased our understanding of the underlying processes governing global vertebrate biodiversity. Here, we present and analyse the global distribution of 10,064 reptile species (99% of extant terrestrial species). We show that richness patterns of the other three tetrapod classes are good spatial surrogates for species richness of all reptiles combined and of snakes, but characterize diversity patterns of lizards and turtles poorly. Hotspots of total and endemic lizard richness overlap very little with those of other taxa. Moreover, existing protected areas, sites of biodiversity significance and global conservation schemes represent birds and mammals better than reptiles. We show that additional conservation actions are needed to effectively protect reptiles, particularly lizards and turtles. Adding reptile knowledge to a global complementarity conservation priority scheme identifies many locations that consequently become important. Notably, investing resources in some of the world’s arid, grassland and savannah habitats might be necessary to represent all terrestrial vertebrates efficiently. The global distribution of nearly all extant reptile species reveals richness patterns that differ spatially from that of other taxa. Conservation prioritization should specifically consider reptile distributions, particularly lizards and turtles.

AIM: Our aims were to test the predictions of the vicariance model, searching for natural, non‐random biogeographical units using data on snake distributions, and to assess the conservation of biogeographical patterns and underlying processes in the poorly studied Caatinga region. LOCATION: Caatinga region, north‐eastern Brazil. METHODS: We revised and georeferenced 7352 snake occurrence records at point localities, by direct examination of voucher specimens in zoological collections and revision of literature data. We tested two predictions of the vicariance model via biotic element analysis using two datasets (all taxa and endemics) mapped onto a 1° × 1° square grid across the Caatinga. Finally, we examined the overlap between recovered biogeographical units and spatial patterns of habitat loss and protected area coverage. RESULTS: We recorded 112 snake species from the Caatinga, of which 22 (20%) are endemics. The predictions of the vicariance model were corroborated by the detection of groups of species with significantly clustered ranges (biotic elements). The analysis with the full dataset detected eight biotic elements, and three endemic biotic elements were found when only using endemics. The three endemic biotic elements correspond to core areas of biotic elements detected with the larger dataset. The average habitat loss for species forming biotic elements was 46%, and was similar among biotic elements. Protected area coverage is different for species from different biotic elements, and most species' ranges are very poorly represented in protected areas. MAIN CONCLUSIONS: The Caatinga harbours a peculiar snake fauna with significantly clustered species ranges concordant with the predictions of the vicariance model. Our results, representing the first formal test of vicariance patterns in the Caatinga, detected poor overlap between biotic elements and protected areas, indicating that biogeographical patterns and processes are largely unprotected in this imperilled and neglected Neotropical region.

Little is known about the threat levels and impacts of habitat loss over the Cerrado Squamate fauna. The region is under severe habitat loss due to mechanized agriculture, accelerated by changes in the Brazilian National Forest Code. The Squamate fauna of the Cerrado is rich in endemics and is intrinsically associated with its surrounding microhabitats, which make up a mosaic of phitophysiognomies throughout the region. Herein we evaluate current conservation status of Squamate biogeographic patterns in the Brazilian Cerrado, the single savanna among global biodiversity hotspots. To do so, we first updated point locality data on 49 endemic Squamates pertaining to seven non-random clusters of species ranges in the Cerrado. Each cluster was assumed to be representative of different biogeographic regions, holding its own set of species, herein mapped according to their extent of occurrence (EOO). We then contrasted these data in four different scenarios, according to the presence or absence of habitat loss and the presence or absence of the current protected area (PA) cover. We searched for non-random patterns of habitat loss and PA coverage among these biogeographic regions throughout the Cerrado. Finally, with the species EOO as biodiversity layers, we used Zonation to discuss contemporary PA distribution, as well as to highlight current priority areas for conservation within the Cerrado. We ran Zonation under all four conservation scenarios mentioned above. We observed that habitat loss and PA coverage significantly differed between biogeographic regions. The southernmost biogeographic region is the least protected and the most impacted, with priority areas highly scattered in small, disjunct fragments. The northernmost biogeographic region (Tocantins-Serra Geral) is the most protected and least impacted, showing extensive priority areas in all Zonation scenarios. Therefore, current and past deforestation trends are severely threatening biogeographic patterns in the Cerrado. Moreover, PA distribution is spatially biased, and does not represent biogeographic divisions of the Cerrado. Consequently, we show that biogeographic patterns and processes are being erased at an accelerated pace, reinforcing the urgent need to create new reserves and to avoid the loss of the last remaining fragments of once continuous biogeographic regions. These actions are fundamental and urgent for conserving biogeographic and evolutionary information in this highly imperiled savanna hotspot.

AIM: To analyze impacts of habitat loss on evolutionary diversity and to test widely used biodiversity metrics as surrogates for phylogenetic diversity, we study spatial and taxonomic patterns of phylogenetic diversity in a wide‐ranging endemic Neotropical snake lineage. LOCATION: South America and the Antilles. METHODS: We updated distribution maps for 41 taxa, using species distribution models and a revised presence‐records database. We estimated evolutionary distinctiveness (ED) for each taxon using recent molecular and morphological phylogenies and weighted these values with two measures of extinction risk: percentages of habitat loss and IUCN threat status. We mapped phylogenetic diversity and richness levels and compared phylogenetic distances in pitviper subsets selected via endemism, richness, threat, habitat loss, biome type and the presence in biodiversity hotspots to values obtained in randomized assemblages. RESULTS: Evolutionary distinctiveness differed according to the phylogeny used, and conservation assessment ranks varied according to the chosen proxy of extinction risk. Two of the three main areas of high phylogenetic diversity were coincident with areas of high species richness. A third area was identified only by one phylogeny and was not a richness hotspot. Faunal assemblages identified by level of endemism, habitat loss, biome type or the presence in biodiversity hotspots captured phylogenetic diversity levels no better than random assemblages. Pitvipers found in the richest areas or included in the IUCN Red List showed significant phylogenetic clustering. MAIN CONCLUSIONS: Usual biodiversity metrics were unable to adequately represent spatial patterns of evolutionary diversity in pitvipers. Current Red List status fails to properly represent evolutionary distinctiveness in the group. Phylogenetic diversity is unevenly distributed even within biodiversity hotspots, and species‐poor areas may harbour high phylogenetic diversity. This reinforces the need for targeted and spatially accurate approaches for adequately representing evolutionary processes in conservation planning.

Aim: To analyse ranges of endemic squamates and anurans in the Cerrado hotspot, searching for coincident distributional patterns in two ecologically distinct clades, and proposing a testable and comprehensive regionalization scheme for the richest and most threatened savanna on the planet. Location: Cerrado region, central South America. Methods: We updated previous point-locality compilations for endemic species of the Cerrado herpetofauna, gathering 4588 unique occurrence records. Using a 1° grid cell, we compared regionalization results of biotic element (BE) and endemicity analyses. To search for a unified regionalization pattern, we compared analyses with a combined dataset (anurans + squamates) with those obtained in single-group analyses. Results: The analysis with the combined dataset recovered more complete results than those in taxon-specific analyses. We found 13 main biogeographical units formed by anurans and squamates that were recovered in both analyses with the combined dataset, and formed our general regionalization scheme. In general, biogeographical units defined by BEs correspond to those recovered by endemicity analysis with the combined dataset. Most recovered biogeographical units were formed both by anurans and squamates, with fewer areas determined solely by one group. Main conclusions: Common regionalization processes operated on both anurans and squamates, shaping general biogeographical patterns for the Cerrado. The general regionalization pattern recovered with anurans and squamates may be valid for other taxa, and should be tested in future studies. As in previous results, most biogeographical units are found over ancient plateaus, separated by peripheral depressions. These major topographical barriers may explain major coincident patterns, linking the evolution of Cerrado biotas to the geomorphological history of the Brazilian shield.

Motivation: We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases. Main types of variables contained: We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset. Spatial location and grain: Neotropics, Behrmann projection equivalent to 1° × 1°. Time period: Specimens housed in museums during the last 150 years. Major taxa studied: Squamata: Serpentes. Software format: Geographical information system (GIS). Results: The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed. Main conclusions: The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.

Aim: Small geographic ranges make species especially prone to extinction from anthropogenic 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 geographic 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. Twothirds 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.

Aim Variation in body size across animal species underlies most ecological and evolutionary processes shaping local‐ and large‐scale patterns of biodiversity. For well over a century, climatic factors have been regarded as primary sources of natural selection on animal body size, and hypotheses such as Bergmann's rule (the increase of body size with decreasing temperature) have dominated discussions. However, evidence for consistent climatic effects, especially among ectotherms, remains equivocal. Here, we test a range of key hypotheses on climate‐driven size evolution in squamate reptiles across several spatial and phylogenetic scales. Location Global. Time period Extant. Major taxa studied Squamates (lizards and snakes). Methods We quantified the role of temperature, precipitation, seasonality and net primary productivity as drivers of body mass across ca. 95% of extant squamate species (9,733 spp.). We ran spatial autoregressive models of phylogenetically corrected median mass per equal‐area grid cell. We ran models globally, across separate continents and for major squamate clades independently. We also performed species‐level analyses using phylogenetic generalized least square models and linear regressions of independent contrasts of sister species. Results Our analyses failed to identify consistent spatial patterns in body size as a function of our climatic predictors. Nearly all continent‐ and family‐level models differed from one another, and species‐level models had low explanatory power. Main conclusions The global distribution of body mass among living squamates varies independently from the variation in multiple components of climate. Our study, the largest in spatial and taxonomic scale conducted to date, reveals that there is little support for a universal, consistent mechanism of climate‐driven size evolution within squamates.

Comprehensive assessments of species’ extinction risks have documented the extinction crisis 1 and underpinned strategies for reducing those risks 2 . Global assessments reveal that, among tetrapods, 40.7% of amphibians, 25.4% of mammals and 13.6% of birds are threatened with extinction 3 . Because global assessments have been lacking, reptiles have been omitted from conservation-prioritization analyses that encompass other tetrapods 4 – 7 . Reptiles are unusually diverse in arid regions, suggesting that they may have different conservation needs 6 . Here we provide a comprehensive extinction-risk assessment of reptiles and show that at least 1,829 out of 10,196 species (21.1%) are threatened—confirming a previous extrapolation 8 and representing 15.6 billion years of phylogenetic diversity. Reptiles are threatened by the same major factors that threaten other tetrapods—agriculture, logging, urban development and invasive species—although the threat posed by climate change remains uncertain. Reptiles inhabiting forests, where these threats are strongest, are more threatened than those in arid habitats, contrary to our prediction. Birds, mammals and amphibians are unexpectedly good surrogates for the conservation of reptiles, although threatened reptiles with the smallest ranges tend to be isolated from other threatened tetrapods. Although some reptiles—including most species of crocodiles and turtles—require urgent, targeted action to prevent extinctions, efforts to protect other tetrapods, such as habitat preservation and control of trade and invasive species, will probably also benefit many reptiles. An extinction-risk assessment of reptiles shows that at least 21.1% of species are threatened by factors such as agriculture, logging, urban development and invasive species, and that efforts to protect birds, mammals and amphibians probably also benefit many reptiles.

A new species of the lizard genus Stenocercus Duméril & Bibron, 1837 is described based on six specimens from Serra da Canastra, Minas Gerais, southeastern Brazil. Similar to S.tricristatus (Duméril, 1851), S.dumerilii (Steindachner, 1867), S.quinarius Nogueira & Rodrigues, 2006, and S.squarrosus Nogueira & Rodrigues, 2006, the new species has a pyramidal head and an enlarged, dorsally projected post-supraciliary scale, like a small horn. It is most similar to S.tricristatus , from which it differs in having a more elongated head in ventral view; a larger number of scales around midbody; a distinctly enlarged, smooth preauricular scale; and probably a larger body size. Moreover, the new species has distinctly keeled scales, with phylloid and mucronate dorsals; no enlarged supraoculars; no neck folds; a vertebral, and a pair of dorsolateral and (weak) lateral crests. A redescription of S.tricristatus is presented for comparison with the new species.