In this study, we provide new morphological data, update geographic distribution, and discuss some issues of conservation of Amphisbaena littoralis, a poorly known species of northeastern Brazil. Meristic characters and patterns of head scalation match the published species diagnosis, but we observed some deviations from the type series. Thus, on the basis of the type series (n = 13) and newly examined material (n = 12), we propose the following redefinitions in some diagnostic characters of A. littoralis: snout–vent length 143–278 mm; tail length 19.3–70 mm; body annuli 251–270; tail annuli 29–34; dorsal and ventral segments of midbody annulus 19–22 and 20–24, respectively; precloacal pores 5–6 (usually 6); and supralabials 3–4 (usually 4). The new records are from eight localities in six municipalities along the coast of Rio Grande do Norte state, extending the known geographic distribution of A. littoralis ca. 172 km south from the type locality. On the basis of the minimum convex polygon method, we estimated the extent of occurrence of the species to be around 5,448 km^2.

On the basis of direct comparisons of type material, literature data, and a sample of 47 other specimens examined, we synonymize Uromacer Ricardinii, described from São Paulo, Brazil, with Dendrophis aurata, described from Suriname and never found there again. This taxon now will be known as Cercophis auratus. Additionally, we redescribe the species and provide a detailed synonymy/chresonomy. Finally, we briefly discuss its disjunct distribution, as well as current knowledge of its conservation status.

The reproductive ecology of the lizard Tropidurus catalanensis (Tropiduridae) from two sites of the subtropical region of southern Brazil was described. In Alegrete municipality, 315 individuals were sampled over a period of 12 mo (2007–2008) to analyze the reproductive biology of males and females. In Santa Maria municipality, the identification of the oviposition sites and monitoring of clutches were performed over a period of 26 mo (2006–2009). Mature individuals of both sexes were found throughout the year, with a strong peak during the mating season (spring). The reproductive cycle of males and females from the studied population was seasonal. The oviposition period extended from spring to early summer and recruitment occurred from late spring to early autumn. There was a trend toward nesting in rocky crevices and soil cavities; communal nests were also recorded. Females reached sexual maturity at larger sizes than males. The development of male secondary sexual characters is probably associated with sexual identification and social hierarchy. Lipid accumulation in males and females was indirectly related to reproductive activity, reaching higher levels during the season with lower food availability (autumn). There was no relationship between environmental variables and the reproductive cycle of males and females.

Tadpoles have been classified into ecomorphological guilds according to their general morphology, feeding behavior, and ecology. Individuals of benthic and nektonic ecomorphological guilds have distinguished morphological traits, but they can also adapt their morphology in response to environmental changes through phenotypic plasticity. We hypothesized that the degree of morphological variation in response to environmental changes would not be equal for different guilds. We predicted a high correlation between morphology and environmental variation for benthic tadpoles, while the morphology of nektonic and intermediate benthic-nektonic tadpoles would be less correlated with environmental variation. We sampled 32 ponds, collected 109 individuals from three species (Boana albopunctata, Dendropsophus minutus, and Scinax fuscomarginatus) and measured five environmental variables for each pond. We used the geometric morphometric approach to describe the morphological variation of tadpoles and a redundancy analysis (RDA) to assess the relationship between the morphological variation of tadpoles and environmental traits for each ecomorphological guild. We detected a phenotype-environment association only for the nektonic tadpole (Dendropsophus minutus). We suggest that tadpoles from different ecomorphological guilds were exposed to different levels of environmental heterogeneity, but benthic and intermediate benthic-nektonic tadpoles actively selected the pond patches that maximized their efficiency, showing less correlation with environmental changes Conversely, nektonic tadpoles were subjected to higher environmental heterogeneity associated with the substrate of the ponds, vegetation, and land use around the pond perimeter, which resulted in higher morphological plasticity.

The number of species of the genus Phymaturus has increased consistently since 1995, when only 10 species had been described. Over the last two decades, this number has risen to 46. This group of lizards is characterized by a flattened body and spiny tail; they are viviparous and herbivorous and inhabit rocky regions, using crevices as refuges. For the present study, an integrative taxonomy approach was used with the aim of rigorously assessing the taxonomic status of a population occupying the Auca Mahuida volcanic field. Evidence from genetics, morphology, and biogeography suggests that this population is a separate lineage from all described species. This new species can be distinguished from close relatives by a longitudinal white dorsal line along the midline at the base of the tail. Special emphasis was put on determining if this taxon presented differences from the nearest relatives of the palluma group: P. roigorum and P. tromen. Consistent differences were found.

Leptodactylidae consists of more than 200 described species distributed throughout the Neotropics. The five species in the genus Crossodactylodes are the only species in this family that complete their entire life cycle in rainwater accumulated between bromeliad leaves. We surveyed bromeliads for Crossodactylodes izecksohni in its type locality: the municipality of Santa Teresa, Brazil's Atlantic Forest. We found C. izecksohni in 12 species of bromeliads. The sex ratio was approximately 1:1. Males were distinguished from females by hypertrophy of upper and forearms and the presence of nuptial pads formed by well-developed spines on the first finger. Eggs, tadpoles, juveniles, and adults were found in bromeliads throughout the year. Males defended clusters of a few bromeliads. Females were also territorial. “Female choice” was the main mate acquisition tactic of C. izecksohni, but “male-male competition” and “satellite strategy” were displayed as well. Males also called from axils with eggs and tadpoles. The clutch structure was a single egg either aquatic-free or non-pendant, slightly suspended above the water level, and attached to a bromeliad leaf. The mean number of eggs and tadpoles found in occupied bromeliads was 2.5 (range 1–7) and 3.5 (range 1–10), respectively. Males guarded and defended eggs and tadpoles against conspecifics and predators. Adults displayed a wide variety of antipredator mechanisms. Limited resources within bromeliads may drive selective pressure and result in the deposition of few large eggs, parental care behaviors, and territoriality. The complex behavior of C. izecksohni makes it a model taxon for the study of behavioral and evolutionary ecology.

Embryonic development is often a dangerous period of the life cycle for many organisms and embryos are often viewed as helpless. Parental care can help reduce mortality in early life stages but embryonic behavior itself can also be important. To assess the ability of frog embryos to actively hatch in response to environmental cues, we conducted an experiment on embryos of the Tobago glass frog (Hyalinobatrachium orientale tobagoense). In this experiment, we compared the hatching response of embryos submerged in water and those exposed to tactile manipulation to controls. The hatching response in submerged embryos was significantly higher compared to the control (mean 52% versus 2%). However, there were no significant differences in hatching response between the embryos in the tactile manipulation treatment compared to the control. These results suggest that Tobago glass frog embryos can actively hatch in response to environmental cues indicating risk, but not all cues elicit a response.

Physalaemus biligonigerus is a leptodactylid frog that is widely distributed in southern South America and a common member of anuran assemblages that breed in temporary ponds near human settlements. Herein, we analyzed its embryonic and larval morphology through the completion of metamorphosis and constructed a normal table of development. In addition, the timing of development and growth data are provided. Development of P. biligonigerus from fertilization through metamorphosis takes 20–24 days. We recognized 46 discrete developmental stages on the basis of readily discerned, unambiguous, external traits that can be identified in preserved specimens. In contrast with the standard Gosner developmental table, we recognized several particularities in the development of this species. The staging criterion based on external gill morphology presented here is a novel approach to distinguish pre- and post-hatching stages, which could also be employed in other anuran species. We found that anal tube loss in P. biligonigerus occurs earlier than Gosner Stage 41; this trait is highly variable among species and should not be used as a standard criterion. Our analysis demonstrates the value of detailed specific staging tables to characterize anuran life cycles. Furthermore, we point out that the use of generalized standard tables might mask the richness of phenotypic variation during the ontogeny of anuran species.