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The South American gymnophthalmid genus Euspondylus is distributed from Venezuela through Peru, with its highest diversity occurring in Peru. Euspondylus paxcorpus sp. nov. is a new species from Junín, Peru possessing prefrontal scales and represented by 60 specimens. The new species differs from all other species by the combination of four supraoculars with supraocular/supraciliary fusion, 5-7 occipitals, a single palpebral scale, five supralabials and infralabials, quadrangular dorsal scales with low keels arranged in transverse series only, 40-45 in a longitudinal count and 22-28 in a transverse count, 12 rows of ventrals in a transverse count and 23-25 in a longitudinal count, and no sexual dimorphism in coloration. The discovery of E. paxcorpus increases the known number of Euspondylus species to 13. Because the coloration patterns of the specimens were greatly different after preservation in alcohol, caution should be used when identifying Euspondylus species from museum specimens.

Phylogenetic studies incorporating multiple loci, and multiple genomes, are becoming increasingly common. Coincident with this trend in genetic sampling, model-based likelihood techniques including Bayesian phylogenetic methods continue to gain popularity. Few studies, however, have examined model fit and sensitivity to such potentially heterogeneous data partitions within combined data analyses using empirical data. Here we investigate the relative model fit and sensitivity of Bayesian phylogenetic methods when alternative site-specific partitions of among-site rate variation (with and without autocorrelated rates) are considered. Our primary goal in choosing a best-fit model was to employ the simplest model that was a good fit to the data while optimizing topology and/or Bayesian posterior probabilities. Thus, we were not interested in complex models that did not practically affect our interpretation of the topology under study. We applied these alternative models to a four-gene data set including one protein-coding nuclear gene (c-mos), one protein-coding mitochondrial gene (ND4), and two mitochondrial rRNA genes (12S and 16S) for the diverse yet poorly known lizard family Gymnophthalmidae. Our results suggest that the best-fit model partitioned among-site rate variation separately among the c-mos, ND4, and 12S + 16S gene regions. We found this model yielded identical topologies to those from analyses based on the GTR+I+G model, but significantly changed posterior probability estimates of clade support. This partitioned model also produced more precise (less variable) estimates of posterior probabilities across generations of long Bayesian runs, compared to runs employing a GTR+I+G model estimated for the combined data. We use this three-way gamma partitioning in Bayesian analyses to reconstruct a robust phylogenetic hypothesis for the relationships of genera within the lizard family Gymnophthalmidae. We then reevaluate the higher-level taxonomic arrangement of the Gymnophthalmidae. Based on our findings, we discuss the utility of nontraditional parameters for modeling among-site rate variation and the implications and future directions for complex model building and testing.

The Hamilton-Zuk hypothesis indicates that parasites may have a negative effect on the appearance of sexual traits within an infected individual. Anolis sagrei, or brown anoles, are small invasive lizards common throughout Florida and many other areas where they have been introduced. The colorful dewlaps under the chins of males are used as a signal during territorial contests with other males and as an ornament to attract females. Anoles may be infected by the malaria parasite Plasmodium floridense. In this study, we investigated the relationship of malarial infection with dewlap color and spectral brightness of A. sagrei. We achieved this by capturing male brown anoles, taking blood samples to examine for malarial infection, and recording the color of their dewlaps. We found that the dewlaps of infected Anolis sagrei had duller coloration than the dewlaps of uninfected lizards. These results provide support for the Hamilton-Zuk hypothesis. Our results suggest that infection by P. floridense could potentially influence fitness of the lizards by reducing the expression of their color signals. Additional research on fitness effects of the malaria parasite on anoles is important for fully understanding this phenomenon. [ABSTRACT FROM AUTHOR]

Climate change is one of the greatest threats to species across the globe, but the threats to tropical animals have largely been overlooked. Tropical high elevation species are distinctly at risk as they will be unable to disperse to habitats with favorable temperatures in the future. Twenty percent of all lizard species may be faced with extinction. Proctoporus unsaacae and P. sucullucu are two thermoconforming lizard species native to the Central Andes mountains where their habitats are predicted to rise over 38C within the 21st century. Because these species do not thermoregulate behaviorally, we predicted that they would have narrow temperature tolerances and would be vulnerable to climate warming. We collected lizards of these species in Peru and tested their critical thermal maxima (CTmax) by slowly heating them until they were unable to maintain normal bodily functions, measured by muscular spasms. Surprisingly, we found that the species have high thermal tolerance with P. unsaacae averaging 38.28C CTmax and P. sucullucu averaging 39.48C. The difference between CTmax and field active body temperatures for both species exceeded 208C. Based on our results, increased environmental temperature will not directly cause these species to suffer death or activity restriction. We posit that these species of Proctoporus and the few other truly eurythermic lizard species may be particularly well suited to surviving global temperature increases. Although global warming will continue to cause the decline and extinction of species worldwide, more research is needed on species with unusual ecologies before making sweeping statements about the dire fate of reptiles. [ABSTRACT FROM AUTHOR]

Montane animals require different adaptations than lowland species because of more severe conditions. Proctoporus lizards of the Andes Mountains experience cold temperatures year‐round, which may affect their activity. Two species of this poorly known genus, P. unsaacae and P. sucullucu, have similar morphology and ecology, but had never been studied in detail. The purpose of this project was to compare the population biology of the two species and to ascertain whether they were more likely to share ecological similarities with phylogenetic relatives or with other unrelated lizards of the Andes. We established two permanent plots in the Sacred Valley of the Incas in Cusco region, Peru, and examined the thermal ecology, movement, sex ratio, longevity, population sizes, growth patterns, reproduction and other factors over a period of 4 years. Proctoporus unsaacae and P. sucullucu were similar in most aspects of their ecology except that P. sucullcu was larger, had smaller population sizes, and fewer recaptures. Both species live exclusively under rocks and are strict thermoconformers who do not actively thermoregulate their body temperatures by basking, as other high Andean lizards do. The two species have reverse sexual dimorphism with P. unsaacae having larger females and P. sucullcu having larger males. The species are highly philopatric with average movement of less than 7 m in a lifetime. Both appear to be relatively long‐lived with an individual P. unsaacae living longer than 2 years 8 months. At both sites, populations age structures had few juveniles and we detected a declining population of P. unsaacae in Urubamba. This project lays the groundwork for more in‐depth studies of the ecology of both species and their high‐elevation habitats. [ABSTRACT FROM AUTHOR]

Aim: Clutch size is a key life‐history trait. In lizards, it ranges over two orders of magnitude. The global drivers of spatial and phylogenetic variation in clutch have been extensively studied in birds, but such tests in other organisms are lacking. To test the generality of latitudinal gradients in clutch size, and their putative drivers, we present the first global‐scale analysis of clutch sizes across lizard taxa. Location: Global. Time period: Recent. Major taxa studied: Lizards (Reptilia, Squamata, Sauria). Methods: We analysed clutch‐size data for over 3,900 lizard species, using phylogenetic generalized least‐square regression to study the relationships between clutch sizes and environmental (temperature, precipitation, seasonality, primary productivity, insularity) and ecological factors (body mass, insularity, activity times, and microhabitat use). Results: Larger clutches are laid at higher latitudes and in more productive and seasonal environments. Insular taxa lay smaller clutches on average. Temperature and precipitation per se are unrelated to clutch sizes. In Africa, patterns differ from those on other continents. Lineages laying small fixed clutches are restricted to low latitudes. Main conclusions: We suggest that the constraint imposed by a short activity season, coupled with abundant resources, is the main driver of large‐clutch evolution at high latitudes and in highly seasonal regions. We hypothesize that such conditions – which are unsuitable for species constrained to laying multiple small clutches – may limit the distribution of fixed‐clutch taxa. [ABSTRACT FROM AUTHOR]

Aim: Understanding the mechanisms determining species richness is a primary goal of biogeography. Richness patterns of sub‐groups within a taxon are usually assumed to be driven by similar processes. However, if richness of distinct ecological strategies respond differently to the same processes, inferences made for an entire taxon may be misleading. We deconstruct the global lizard assemblage into functional groups and examine the congruence among richness patterns between them. We further examine the species richness – functional richness relationship to elucidate the way functional diversity contributes to the overall species richness patterns. Location: Global. Methods: Using comprehensive biological trait databases we classified the global lizard assemblage into ecological strategies based on body size, diet, activity times and microhabitat preferences, using Archetypal Analysis. We then examined spatial gradients in the richness of each strategy at the one‐degree grid cell, biome, and realm scales. Results: We found that lizards can best be characterized by seven "ecological strategies": scansorial, terrestrial, nocturnal, herbivorous, fossorial, large, and semi‐aquatic. There are large differences among the global richness patterns of these strategies. While the major richness hotspot for lizards in general is in Australia, several strategies exhibit highest richness in the Amazon Basin. Importantly, the global maximum in lizard species richness is achieved at intermediate values of functional diversity and increasing functional diversity further result in a slow decline of species richness. Main conclusions: The deconstruction of the global lizard assemblage along multiple ecological axes offers a new way to conceive lizard diversity patterns. It suggests that local lizard richness mostly increases when species belonging to particular ecological strategies become hyper‐diverse there, and not because more ecological types are present in the most species rich localities. Thus maximum richness and maximum ecological diversity do not overlap. These results shed light on the global richness pattern of lizards, and highlight previously unidentified spatial patterns in understudied functional groups. [ABSTRACT FROM AUTHOR]

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. 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. [ABSTRACT FROM AUTHOR]

The tribe Cercosaurini is one of the most poorly studied groups of the lizard family Gymnophthalmidae. Recent studies have suggested that two cercosauriine genera,NeusticurusandProctoporus, are polyphyletic. The aim of the current study was to rectify the polyphyletic relationships and construct a phylogenetic taxonomy of the Cercosaurini that is congruent with evolutionary history.Neusticurusis divided into two genera, one of them new (Potamites), based on the clades recovered by molecular studies and previously discussed morphological data.Proctoporusis divided into three genera, one of which is new (Petracola), while an older name (Riama) is resurrected for another. All five genera are described and defined and taxonomic keys are presented. This study represents an important advance in rectifying the taxonomy of the Cercosaurini. Many other para- and polyphyletic genera remain in the Gymnophthalmidae and much future work on this group is warranted. © 2005 The Linnean Society of London,Zoological Journal of the Linnean Society, 2005,143, 405–416. [ABSTRACT FROM AUTHOR]

Because of the poor state of knowledge of many of the gymnophthalmid genera, systematic revision is necessary to render the classification consistent with evolutionary history. To that end, I conducted a review of the species of three genera of the Cercosaurinae which appear to form a monophyletic group:Cercosaura, Pantodactylus, and Priono-dactylus. Phylogenetic analysis of 61 morphological characters was conducted after specimens of all species were examined to evaluate the composition of each taxon. The phylogenetic reconstruction suggested that the genus Pri-onodactylus was paraphyletic. A new phylogenetic classification is proposed that synonymizesPantodactylus and Prionodactylus with Cercosaura. Cercosaura is redefined to include 11 species and seven subspecies. A key is provided to distinguish among species. [ABSTRACT FROM AUTHOR]

The article investigates Plasmodium infection in Anolis lizards at La Selva Biological Station, Costa Rica, revealing widespread malaria presence among various species, including Anolis humilis and Anolis limifrons. The study found that the infection rates did not significantly differ between these two species, though some species like Anolis lemurinus and Anolis capito were also found to carry Plasmodium.

An introduction is presented in which the editor discusses various reports within the issue on topics including changes in herpetology; understanding reverse amphibian population declines; and future challenges to be expected by lizard ecologists.