We redescribe Atractus punctiventris based on the examination of its holotype, two topotypes, and two additional specimens recently collected. We describe two new species of Atractus with 15 dorsal scale rows, previously confused with Atractus insipidus, from the eastern and western portions of Brazilian Amazonia, respectively. The new species are recognized on the basis of unique combinations of morphological characters. We compare Atractus punctiventris and the two new species with all congeners from most lowland provinces of cis-Andean South America. We discuss potential affinities of the three species, mainly by sharing exclusive hemipenial traits with congeners placed in different phenetic groups, and allocate them to distinct species groups of Atractus.

The conservation of large, long-lived turtle species can be a challenging issue because their life-history strategies make populations sensitive to changes in adult survivorship and populations may be difficult to sample. The Alligator Snapping Turtle (Macrochelys temminckii) is a large freshwater turtle species occurring in North America for which commercial harvest has severely reduced populations throughout the species range. Given recent population declines and a general deficit of demographic knowledge for Macrochelys, we conducted a mark–recapture study of M. temminckii from 1997–2013 in Spring Creek, Georgia, USA. We made 166 captures of 75 individuals using baited hoop-net traps and skin-diving searches. The observed and estimated population structure described the adult sex ratio as even and adults as more abundant than juveniles. Apparent survival was higher for adult males (0.98) and females (0.95) than for juveniles (0.86), and we estimated a population density of 13–14 turtles/stream kilometer. The survival estimates for adult M. temminckii are among the highest of all freshwater turtle species reported in the literature. We used the empirical demographic parameters described here and a literature review to build an updated population model for M. temminckii; the model estimated a finite rate of population increase consistent with a growing population (λ = 1.036) at Spring Creek, and population viability analysis found the population growing over the next 50 yr in 100% of simulations. Application of our model to published survival estimates from two impacted western populations indicated a declining population (λ = 0.563) with a high risk of extirpation in Oklahoma and a population with a slow rate of decline (λ = 0.978) but approaching stability in Arkansas. Simulations identified combinations of survival values which generate viable populations and also characterized population structure resulting from viable scenarios. This is the first study to document a stable and viable population of Macrochelys. We suggest that the population parameters described at Spring Creek are the best approximation of reference demographic conditions for Macrochelys to date, and this study provides a general framework applicable for large, long-lived, endangered turtle species for which demographic data are unavailable.

Understanding community assembly is a fundamental goal of ecology and evolutionary biology, because it provides insight into how a given landscape changes in a synergistic fashion. With the current background of global environmental change, studies of how habitat alteration affects local communities often focus on species' responses to community-level changes instead of responses to specific ecological factors that elucidate the roles each factor plays in the final synergistic response. Here, we focus on the specific ecological mechanisms that drive changes in community structure. We investigated compositional patterns of lizard communities among natural and altered habitats (vegetatively sparse, natural, and dense) in the desert steppe ecosystem of Inner Mongolia, China. Habitat alteration induced significant changes in community composition of lizards and was associated with significant changes in both biotic and abiotic niches. Our preference (soil, thermal, and prey) and performance (locomotor, antipredator, and competitive) experiments identified many of the biotic and abiotic factors shaping lizard community responses to habitat change. In the natural habitat, where Phrynocephalus frontalis and Eremias multiocellata codominate, P. frontalis experienced low overlap (across lizard species) in preferred prey. Eremias multiocellata preferred the thermal environment of the natural habitat (and dense habitat), but this one factor did not fully explain its codominance. Phrynocephalus frontalis dominated in the sparse habitat, where this lizard species experienced its preferred tight soil and warm thermal environment and experienced low overlap of preferred prey. In the dense habitat, where E. argus dominates, P. frontalis and E. multiocellata exhibited impeded locomotor performance, whereas E. argus was not impeded by vegetation density. Eremias argus also preferred the thermal environment of the dense habitat (and natural habitat). Our results suggest, furthermore, that adult predation risk was not a major determinant of community divergence among habitats and that competition likely plays a more important role. Interspecific competition for microhabitat use may explain the low abundance of E. argus in the natural habitat and the low abundance of P. frontalis in the dense habitat. Overall, our assessment of lizard preferences and performances explained community composition across habitats. Our focus on ecological mechanisms associated with habitat alteration highlights the importance of vegetation conservation in lizard community management.

We present the first taxonomic review of the genus Phrynomedusa since its description with diagnoses of the genus and species. We present a broad literature review of the genus and provide updates and remarks about the type series, tadpoles, calls, geographic distribution, and natural history of the species of Phrynomedusa. Additionally we describe a new species from município de São Luiz do Paraitinga, state of São Paulo, Brazil. Phrynomedusa dryade was initially identified as Phrynomedusa marginata; however, an integrated analysis of morphological and molecular characters enabled its recognition as a separate new species. For the first time, the advertisement call for one species of Phrynomedusa is described in detail. We describe the tadpole and present some field notes about the activity and biology of this new species.

In recent decades, a renewed interest in comparative studies of embryonic ontogeny in anurans is taking place. Toad embryos are often employed as model organisms, and scarce attention has been put on interspecific variations. In this work we analyze the development of transient embryonic and larval structures in 21 species in five genera of Bufonidae. These species vary in their ovipositional mode and the type of environments where the embryos and tadpoles develop, including ponds, streams, and axils of leaves of terrestrial or epiphytic plants. Comparative anatomical studies and sequence heterochrony analyses show that primary morphological variations occur in the morphology at the tail-bud stage, the arrangement and development of the external gills, adhesive gland type and division timing, growth of the dorsal hatching gland on the head, configuration of the oral disc, emergence and development of the hind limbs, and presence of the abdominal sucker. Some of these transformations are best explained by phylogeny (e.g., early divergent taxa of bufonids have embryos with kyphotic body curvature, Type C adhesive glands, and a very small third pair of gills). Other traits might be correlated with reproductive modes (e.g., phytotelmata embryos hatch comparatively late and show an accelerated development of hind limbs). Because these actual variations are not well studied (e.g., less than the 10% of the known diversity of bufonids has been studied from this perspective), comprehensive analyses are required to interpret character evolution and the relationship with reproductive modes within the family.

We infer species relationships within Lynchius, a frog genus with four species distributed along the paramos and cloud forests of the Andes of northern Peru and southern Ecuador, and assess species diversity in light of comparative analyses of anatomical traits and inferred relationships. Phylogenetic analyses rely on ~7000 base pairs of mtDNA and nuDNA sequences aligned using similarity-alignment and tree-alignment and optimized under maximum likelihood and parsimony criteria. Inferred relationships place Lynchius as the sister group of the widespread genus Oreobates and this clade as the sister group of the high Andean genus Phrynopus. Our analyses corroborate the dissimilar species Lynchius simmonsi as part of this clade and place it as the sister group of the remaining species of Lynchius. Parsimony and maximum likelihood analyses differ in the internal relationships of Lynchius with respect to the placement of L. flavomaculatus, L. nebulanastes, and L. parkeri, but support the existence of two unnamed species. External morphological comparisons provide diagnostic characters for the two new species, which are named and described herein. Lynchius tabaconas is sister to L. flavomaculatus and occurs at ~2800 m in the cloud forests of Santuario Nacional Tabaconas-Namballe, Cajamarca, Peru. Lynchius oblitus occurs in the same area but at a higher elevation (~3300 m) and is sister to a clade formed by L. flavomaculatus and L. tabaconas in parsimony analyses and to L. nebulanastes in maximum likelihood analyses. We provide a new diagnosis for each of the six species and for the genus, as well as some natural history notes.

A number of fossil snake vertebrae were collected from Early Pleistocene deposits exposed on a hill surface at Gogayama, Nakijin village, Okinawajima Island, along with many other vertebrate fossils. These represent the oldest fossil records of snakes for the whole Ryukyu Archipelago. We identified each of these fossil snake vertebrae to the lowest taxonomic category possible based on diagnostic features elucidated in our previous study of extant snakes from Japan and adjacent regions. As a result, the vertebrae of at least four genera—Cyclophiops and Dinodon of the family Colubridae, Protobothrops (formerly Trimeresurus) of the family Viperidae, and Sinomicrurus of the family Elapidae—were recognized. Of these, vertebrae identified as belonging to the genus Dinodon were further divided into two distinct forms, although both resembled D. rufozonatum, an extant species that does not presently occur in Okinawajima or any of the surrounding islets in the central Ryukyus. Vertebrae identified as belonging to the other three genera were largely similar to those of the three extant species currently occurring in Okinawajima but with slight differences.