Atractus gigas was described based on a single specimen from western Andes of Ecuador. Although recently, a second specimen of A. gigas was reported close to the type locality just on the basis of photographic vouchers. During the examination of Ecuadorian and Peruvian collections, we found additional specimens of this poorly known snake. We also collected new individuals of Atractus gigas during fieldwork carried out on northeastern portion of the Peruvian Andes. In this paper, we report new specimens, localities, and data on meristic, morphometric and color pattern variation for the species. We associate the variation displayed by these character systems with sexual, geographic, and ontogenetic phenomena respectively. We provide detailed comparisons and diagnosed Atractus gigas from all others members of this highly diverse and complex genus, and comment on their natural history and ontogeny.

Herein we report the rediscovery of the torrent frog Hylodes babax, a species considered as “Data Deficient”, based on specimens from two new localities: Parque Estadual da Serra do Brigadeiro, in the Mantiqueira mountain range, and Floresta Estadual do Uaimií, in the southern Espinhaço mountain range, both conservation units in the State of Minas Gerais, southeastern Brazil. These records are the first for the species outside of its type locality. FLOE Uaimií is also the most inland record for H. babax. Notes on its natural history and comments about biogeography in southeastern Brazil are also presented.

Anurans living along the Andes cordillera exploit several thermal environments that vary with altitude and latitude. Studies on moderate and high-elevation tropical species suggest co-adaptation between thermal ecology and thermal physiology. Our objective was to test whether this is the case for three Patagonian anuran species. We focused on larval stages and analyzed critical maximum and minimum temperatures granting survivorship. The species studied were Abodes gargola, Pleurodema bufoninum and Rhinella spinulosa papillosa. Alsodes gargola lives primarily in high-elevation lakes and montane streams, has long larval development and overwinters. In contrast, tadpoles of P. bufoninum and R. s. papillosa use marshes and lower elevation ponds, and develop in three months. Tadpoles of Abodes gargola tolerated experimental temperatures up to 32°C and those of the other two species lost the ability to move at temperatures near 38°C. Tadpoles of all species tolerated experimental exposure to 0°C for a limited period of time, but A. gargola had higher mortality rates when exposed to freezing than the other two species. These results are consistent with some traits of thermal ecology, exemplified by the higher thermal stability of the environments used by A. gargola. However, other factors such as physiological trade-offs may partially explain this pattern.

Coral snakes in the genus Micrurus are widely distributed in the Neotropics, with more than 50 species already described in this region. They are primarily ground or leaf litter dwellers, feed on snakes or other elongate vertebrates, and tend to reproduce during the rainy season. We present data on the biology of Micrurus pyrrhocryptus from two semideciduous forests of Mato Grosso do Sul state, western Brazil. Two snake species were consumed: the dipsadid Sibynomorphus lavillai and the typhlopid Typhlops brongersmianus. Sexual dimorphism is marked in M. pyrrhocryptus, with males attaining larger sizes and having longer tails. Activity was concentrated in the wet season, when reproduction occurs. The defensive behavior in this species is similar to that displayed by other Micrurus, although less pronounced.

After the study of a diverse collection of Phymaturus from three Argentinian institutions and additional samples collected in the last two years we discovered several populations of uncertain taxonomic status. Based on 93 morphological characters of squamation, color pattern, gular and nuchal folds, precloacal pores, and morphometric data, we conclude that at least four of those are independent lineages which require formal description. Characters related to sexual dimorphism and dichromatism as well as the ontogenetic change of several others, from juvenile to adult specimens, are described. According to the most recent revision of the genus (Lobo and Quinteros, 2005a) and considering the descriptions made in the last four years, the taxonomic composition of the genus was raised to 23 species. In this study we provide the formal description of four additional new taxa, including their diagnosis and detailed comparisons with other members of their species groups. Two new species belong to the patagonicus group (provinces of Chubut and Rio Negro, in Patagonia between 46° and 41° of latitude) while the other two belong to the palluma group (Neuquén and Catamarca provinces, western Argentina, 39° and 27–26°30' of latitude respectively). With the exception of one case for which four localities are reported, all new species are restricted to their type localities. This fact confirms a common historical distributional pattern for most species of the genus.

Proceratophrys melanopogon is always observed at high altitudes, having never been diagnosed in altered areas. The advertisement call of this species is described from Serra do Brigadeiro, state of Minas Gerais, southeastern Brazil. The call consists of a multipulsed (12–41 pulses) note with a mean duration of 0.39 s, emitted sporadically, and a dominant frequency around 1179 Hz. By comparing the call of P. melanopogon with other species of the genus it is possible to establish similarities and differences among the analyzed parameters.

We describe the composition, abundance and some natural history aspects of the snake community of Parque Nacional de Sete Cidades (PNSC), Municipality of Piracuruca, State of Piauí, northeastern Brazil, and compare its composition with those of nine other localities in Brazil. We used three sampling methods: time-constrained search, pitfall traps with drift fence and incidental encounters, and recorded 87 snakes, belonging to five families (Boidae, Colubridae, Dipsadidae, Elapidae, Viperidae), 18 genera and 24 species. The dominant species was Thamnodynastes sp. A (13.1%), followed by Oxyrhopus trigeminus and Micrurus ibiboboca (10.3%). There was a predominance of terrestrial species and those with diurnal activity. The typical cerrado showed the greatest species richness, and the lowest richness were recorded in the campo limpo (grasslands) and cerrado rupestre (rocky grasslands). Species composition of the PNSC community was more similar to those of the Cerrado-Caatinga transition zone and the Caatinga,

The pattern of annual reproductive activity and other reproductive characteristics were studied in a population of the gymnophthalmid lizard Ptychoglossus bicolor that inhabits the leaf-litter of an organic coffee shade plantation located on the Cordillera Oriental of the Colombian Andes. Males and females reached sexual maturity at a similar body size (approximately 45 mm snout vent length); however, adult males were significantly larger than females in body size, body mass, and head size. All adult males showed convoluted epididymides, enlarged testes with continuous spermatogenesis and spermiogenesis throughout the year. However, testis mass varied significantly among months and between seasons and was positively correlated with the amount of rainfall. Females were reproductively active (vitellogenic, ovigerous, and vitellogenic and ovigerous simultaneously) during all months of the year, and clutch size was always two. Abdominal fat bodies did not vary over time, neither in males nor in females, Together with the observation of juveniles in most months, this indicates a pattern of continuous reproductive activity and confirms the production of multiple clutches in this population. This aseasonal reproductive pattern suggests a continuous availability of resources that can be supplied in favourable conditions offered by the organic farming.

We describe the advertisement and release calls of Rhinella jimi based on recordings of four individuals from Natal, Rio Grande do Norte State, Brazil. During recordings, we made behavioural observations and used the observed patterns to infer aspects of the mating system of the species. Behavioural patterns suggest that this species is a short, explosive breeder with males actively searching for mates in a scramble competition fashion. Release calls are formed by random combinations of notes that vary in the number of pulses (2–5) and amplitude, but with dominant frequency equal to the advertisement call of the individual. Advertisement calls are formed by trains of repeated pulsed notes with 6.29 ± 2.29 s duration and average dominant frequency of 600.59 ± 51.71 Hz. Calls begin with a rising phase composed of 15.65 ± 7.09 notes during which frequency and amplitude rise to before levelling out along the remaining of the call. The number of pulses per note (2–3) is within the range of several species in the group, but this character likely has a large intrapopulational variation. Rhinella jimi is also similar to R. cerradensis because of its high variation in call duration. However, comparisons are hampered because most call descriptions for members of the R. marina group do not quantify individual or population level variations in call traits. Advertisement calls are fundamental aspects of frogs' natural history, and most likely determinant for the ecology and evolution of the large toads of the R. marina group in South America. Adequate descriptions, quantification of individual and population-level variations, and statistical comparisons are needed before ecological and evolutionary scenarios for these frogs can be proposed and adequately tested.

We determined the anurofauna composition and variation in a terra-firme forest surveyed during one rainy season. The study was carried out in the Fazenda Experimental of the Universidade Federal do Amazonas, Manaus, Amazonas, Brazil. Between November 2008 and May 2009, three samples were taken at night in 41 plots distributed across a 24 km2 grid. Twenty one plots were located away from water bodies (non-riparian plots) and the remaining 20 plots were located alongside the water bodies (riparian plots). Sampling was performed using standardized sampling methods: visual and auditory surveys performed simultaneously. A total of 6,677 individuals belonging to 33 species and nine families (Aromobatidae, Bufonidae, Centrolenidae, Ceratophryidae, Hylidae, Leptodactylidae, Microhylidae, Pipidae and Strabomantidae) were recorded. The number of species ranged from 23 species at the beginning of the rainy season to 26 species at the end of the season. Twenty-four species were detected in non-riparian plots, whereas 28 species were recorded in riparian plots. Fifteen species were recorded throughout the three sampling periods. The most abundant and widely distributed species in the study area were those with reproductive specializations. Differences in species richness and abundance between riparian and non-riparian plots were observed during sampling periods: in general, in the riparian plots the number of species and number of individuals were higher than those recorded in the non-riparian plots. These differences were related to the presence of species recorded exclusively in riparian plots, corresponding to species dependent on water bodies for reproduction. Differences in species composition between our study site and other nearby areas in central Amazonia may reflect local characteristics, such as variation in topography and presence of specific sites for anuran reproduction.