In this study, we evaluate the role of local and regional factors in shaping the anuran assemblages in the Cerrado biome by contributing to the knowledge on the diversity patterns of different Cerrado vegetation types in southeastern Brazil. We measured richness and abundance of ground dwelling frogs in a gradient of vegetation structural complexity, varying from grassland (campo sujo) to forest (cerradão), using pitfall traps with drift fences and standardized efforts. We also measured vegetation structure by directly counting its components in the field. We found differences in richness and abundance among vegetation types, with richness being higher at more open vegetation types, and abundance being higher at the forest due to the extremely high number of captures of Rhinella ornata, a species from the Atlantic Forest biome. A concordant pattern in anuran diversity and vegetation structure suggests an important role of the habitat in structuring diversity in this group, with open vegetation types sharing both more similar anuran assemblages and vegetation. The higher diversity of Cerrado anurans observed in the open vegetation types in southeastern Brazil is in phase with diversity accounts for other groups of the herpetofauna throughout the biome, and it supports a prevalence of the regional processes over local determinism, a hypothesis that should be formally tested for amphibians with large-scale standardized sampling.

The traditional foraging mode dichotomy in lizards has been one of ambush predators vs. wide ranging predators. Each mode has been associated with its own suite of other complementary characteristics, including metabolic rates, sensory capacities, as well as predator and prey species. While foraging mode within lizard families is often consistent, few studies have compared the foraging modes of sympatric members of a clade in which one species is nocturnal and the other diurnal. Hemidactylus frenatus, an introduced, nocturnal house gecko, and Gonatodes albogularis, a native, diurnal species, inhabit disturbed habitats in Costa Rica. Using traditional movement-based indices, moves per minute (MPM) and percent time spent moving (PTM), we found H. frenatus to move significantly less (MPM = 0.47) and spend significantly less time moving (PTM = 0.74%) than G. albogularis (MPM = 0.97, PTM = 3.94%) during peak activity times. One reason for this difference in activity level could be the beneficial effects of artificial lighting in attracting arthropods to H. frenatus foraging areas.

Markers of oxidative status may become important tools in conservation biology as a means of evaluating survival and reproductive expectations in organisms, as well as to elucidate the effects of anthropogenic impacts on populations living in their natural environments. The objective of the present study was to evaluate seasonal variations in oxidative status in a population of Tropidurus catalanensis through the analysis of lipid peroxidation levels and quantification of activity of the antioxidant enzymes superoxide dismutase, catalase, and glutathione S-transferase in liver, kidneys, and tail muscle. This lizard inhabits southern Brazil, in the Pampas grasslands. A total of 73 animals were collected over a 1-year period through active search and hand capture, separated into males and females, euthanized with ketamine hydrochloride, and frozen. A detailed approach on the variation of climatic variables over the seasons is also provided in order to subsidize a better comprehension of seasonal variation in oxidative stress biomarkers of T. catalanensis. Results obtained reveal that this lizard exhibits a clear pattern of seasonal variation in redox balance markers across different tissues. Antioxidant system of these animals is highly efficient, being able to maintain constant levels of lipid peroxidation in liver and muscle in males and in all tissues studied in females. In the renal tissue, an increase in lipid peroxidation was found only in males in spring. The enzymatic antioxidant defense system studied herein exhibited tissue and sex-specific responsiveness, and was possibly modulated by factors both abiotic (e.g., photoperiod, temperature, radiation, precipitation) and biotic (e.g., reproductive cycle, nutritional status, type of food consumed).

Species of Bufonidae and Leptodactylidae are common in the Colombian tropical dry forest. Although some of them are associated with active foraging and consumption of termites and ants, their trophic ecology is mostly unknown. The diet of five anuran species of Bufonidae (Rhinella horribilis, R. humboldti) and the leptodactylid subfamily Leiuperinae (Engystomops pustulosus, Pleurodema brachyops, and Pseudopaludicola pusilla) was examined at six sites of the Colombian Caribbean in fragments of dry forest and different land uses. A total of 310 food items were identified. The greatest contribution was represented by Coleoptera, Hymenoptera (Formicidae), Isoptera, and Diptera. The species differed in number and volume of prey. Except for Pseudopaludicola pusilla, which behaves as a generalist predator, species had high intake of termites and ants. Engystomops pustulosus preferred termites, Pleurodema brachyops had high consumption of ants and termites, and the two bufonid species were myrmecophagous. Except for Pseudopaludicola pusilla, predator and prey size was related. Most species have overlapping diets (spatially and temporally) when analyzing food items identified at the order level. However, the richness of different prey within these orders allows the coexistence of species. The diet of these species presents similar trends in different habitats throughout their distribution area.

The golden lancehead pitviper (Bothrops insularis) is a critically endangered species endemic to the Queimada Grande Island, a federally protected area located 33 km off the southern coast of São Paulo State, Brazil. Adults have specialized diet, preying upon migrating birds, and the species' reproductive efficiency is quite lower than its continental related species, B. jararaca. Potential threats to B. insularis include illegal removal, introduction of exotic species or diseases, and catastrophic events such as wildfire. The population size of B. insularis was estimated at 2,899 individuals (CI 95% = 1,903; 4,416) in its forested habitat using distance sampling. This is the first population estimation using 3D area model for a reptile habitat. Bothrops insularis was more sensitive to harvesting of few individuals yearly than a catastrophic event that causes mortality over 95% of the entire population in a 100-year simulation period. Prioritizing conservation efforts of reptile species in Brazil depends on simple yet robust monitoring methods like the one presented here. This study was only made possible through the concatenation of government, management, and scientific interests. Such synergism should be encouraged in conservation policies in Brazil, especially in remote locations.

The taxonomic history of Steironotus arenariusTschudi, 1845 is one of the most problematic among all tropidurids. The species was originally described supposedly based on four specimens collected in Peru and deposited by J.J. von Tschudi at the Musée d'Histoire Naturelle de Neuchâtel, Switzerland. However, the syntypes were not re-examined until Roux (1907: Rev. Suisse Zool. 15:293–303) performed a revision of Tschudi's Peruvian collection. Fritts (1974: Mem. San Diego Soc. Nat. Hist. 7:1–89) revised the taxonomy of Stenocercus and endorsed Roux's allocation of Steironotus arenarius in TropidurusWied, 1825, although he never analyzed Tschudi's types. Ortiz (1989: Bull. Soc. Neuchâtel. Sci. Nat. 112:47–64) was the first contemporary systematist to re-analyze Tschudi's specimens for his catalogue of the lizard types of the Musée d'Histoire Naturelle de Neuchâtel. His compilation attempted to clarify the number, location, and identity of the types of Steironotus arenarius found at the Musée d'Histoire Naturelle de Neuchâtel and Naturhistorisches Museum Basel. Subsequent authors overlooked or opted for not following Ortiz and endorsed the allocation of Steironotus arenarius in Tropidurus. Although Ortiz was the only one to re-analyze the types of Steironotus arenarius after Roux, he never provided full morphological descriptions or detailed comparative notes to support his taxonomic conclusions. Herein, I clarify the taxonomic history of Steironotus arenariusTschudi, 1845 and Tropidurus tschudiiRoux, 1907, and confirm that Tschudi's syntypic series is a composite of two genera, i.e., MicrolophusDuméril and Bibron, 1837 and StenocercusDuméril and Bibron, 1837. I ultimately designate a new lectotype for Steironotus arenariusTschudi, 1845 and provide recommendations for correcting uncorroborated taxonomic arrangements, bringing stability to tropidurid taxonomy.

Cloacae and peritoneal canals of species of Testudines, Crocodylia, and Aves were analyzed with the purpose of identifying and describing their morphology and investigating their possible relationship with other cloacal structures. Studies were conducted from dissections and routine histological preparations. The cloaca is located in the pelvic cavity and differs between Testudines and Crocodylia. In the former, the cloaca is divided into three compartments—the coprodeum, urodeum, and proctodeum—without folds separating them. In contrast, in Crocodylia the coprodeum, urodeum, and proctodeum are separated by discrete folds, the coprourodeal and uroproctodeal folds. The visceral layer of the peritoneum forms the peritoneal canal and also differs in Testudines and Crocodylia. In the former, the cranial opening of the peritoneal canal is lateral to the urogenital sinus and the canal is caudally projected into the phallus, laterally followed by the ejaculatory groove until the caudal end of the organ. In Crocodylia, the cranial opening of the peritoneal canal is lateral to the coprodeum and the canal extends caudally until reaching a papilla in the body of the phallus, where it terminates. Histologically, the mesothelium of the peritoneal canal has a simple pavement appearance. In Testudines, regions with a simple cubic epithelium were found, indicating intense cell activity. The lamina propria is characterized by a thickening of the connective tissue, moderately dense with a variable thickness and with a layer of bundles of smooth muscle arranged in different directions. In Caiman yacare, bundles of striated skeletal muscles were found on the loose connective tissue that involves the peritoneal canal. The cloacal and peritoneal fluids have a strong protein similarity. The peritoneal canal reflects functional characteristics related to reproduction. No peritoneal canals were found in birds.

Oviparity is the most widespread reproductive mode among reptiles. The South American genus Liolaemus contains both oviparous and viviparous species, the latter generally dominating at high latitudes and high elevations. We report for the first time evidence suggesting oviparity in Liolaemus variegatus, an Andean lizard endemic to Bolivia. We record its presence at elevations up to 4,200 m on the Cordillera de Tiraque, which is among the highest localities for oviparous lizards in the world. We characterize the content of oviductal and aborted eggs and the structure of the shell of aborted eggs. Eggshell is 66.7 µm thick and is composed of an outer calcareous layer, a thick fibrous mesh, and an inner boundary. The most abundant mineral crystals in the calcareous layer constitute a matrix of formless calcite depositions forming transversal grooves on the outer surface. In the bottom of those grooves are other pseudo-hexagonal prism crystals that could be aragonite and which contain some potassium. Computed tomographic reconstructions revealed a small region of higher density inside a flank of the yolk sac. Most of the oviductal and aborted eggs had non-distinguishable embryos even after opening them under an optic microscope, suggesting that the embryos were incipient. However, the oviductal eggs from two females were at embryonic stages 24–25. We document clutches of 4–8 eggs, which comprise up to 96% of female body mass without eggs. Future comparisons of egg morphology may shed some light on the physiological changes associated with the transition from oviparity to viviparity.

We analyzed reproductive and feeding habits of Leptodeira annulata based on a sample of 136 specimens from eastern Amazonia and compared our data with information from the literature of other populations of L. annulata, as well as of Imantodes cenchoa. As a result, we detected sexual bimaturism, a continuous reproductive cycle, and no sexual dimorphism regarding snout–vent length. Anurans represent the predominant food item of L. annulata in the region, and these snakes do not exclude small prey from their diet, behaving as opportunistic feeders. Interspecific differences in relative fecundity between L. annulata and I. cenchoa may reflect body characteristics that would represent adaptations to the different reproductive strategies of the two species. Despite the conservative nature of some features of the life-cycle strategies of L. annulata, we demonstrate that reproductive strategies of the species may exhibit geographic variation based on the results of other studies approaching the same species in other areas of South America. Considering that larger conspecific females show higher fecundity, it is possible that natural selection favors sexual maturity of females to occur later.

This study presents the description of the advertisement call and a second call type of Scinax dolloi, recorded at its type locality, Vila de Maringá, Itatiaia, in the State of Rio de Janeiro, southeastern Brazil. The advertisement call consists of a multi-pulsed note showing upward modulation in the initial pulses. The second call type is usually emitted between advertisement call notes and consists of a modified version of the advertisement call with juxtaposition of the pulses that form the note in its structure. The advertisement call pulse rate, number of pulses and note duration best differentiate Scinax dolloi, S. hayii, and S. perereca. Despite some overlap in the spectral components (frequency range and dominant frequency), the three species present significantly different means.