We here describe a new species of Atractus from the Atlantic Forest of Alto Paraná Paraguay. The new species differs from other Atractus by the combination of the following characters: 17 dorsal scale rows without reduction, six supralabial and infralabial scales, only one post-ocular, a uniformly gray dorsum and a whitish belly with iridescent tonalities. The new species of Atractus is known only by the holotype which is a female specimen, and two paratypes. This is the third species of the genus recorded in Paraguay. Given the current status of the Atlantic Forest in Paraguay and in South America, the present species might be classified as highly threatened.

We describe the advertisement calls of Dendropsophus branneri, Phyllodytes melanomystax, and Scinax agilis, and present new information on the advertisement call of Scinax auratus. We also describe the territorial call of P. melanomystax. We provide the power spectrums, audiospectrograms, and waveforms of all calls. Vocalizations were recorded in the Municipalities of Camaçari, Elísio Medrado, Feira de Santana, and Mata de São João, State of Bahia, Brazil. Based on the advertisement call characteristics of these species, we discuss some aspects related to their taxonomy.

The present paper provides diagnostic characters from external morphology and osteology that reinforce the specific recognition of the frog Odontophrynus barrioi, describes its advertisement and encounter calls, and extends its distribution range. Odontophrynus barrioi is distinguished from all other species of the genus principally by the large size of adults, great number of irregularly arranged postorbital and temporal glands, lack of both a light vertebral line and keratinous spines, alary process of the premaxilla short and wide, pterygoid process of the maxilla well developed, and high preorbital process of the maxilla. The advertisement call consists of a trill of a single repeated and pulsed note with a low dominant frequency. The encounter call consists of only one note of similar frequency as the advertisement call, but longer in time duration. We report new records of O. barrioi from Catamarca, La Rioja, and San Juan Provinces (Argentina), that increase considerably the range of this previously poorly known species.

Boids occur in North, Central and South America, the West Indies, Africa, including Madagascar, Asia and in some Pacific Islands as well. In Brazil they occur in a wide range of habitats and climatic zones throughout the country. This study presents reproductive and morphometric data for eleven Brazilian boid species and subspecies (Boa c. contrictor, B. c. amarali, Corallus caninus, Co. hortulanus, Co. cropanii, Epicrates c. cenchria, Ep c. assisi, Ep c. crassus, Eunectes murinus, Eu. deschauenseei and Eu. notaeus) including some morphometric data for Madagascan (Sanzia madagascariensis and Acrantophis dumerili) and Pacific boas (Candoia carinata, Ca. aspera and Ca. bibroni). These large snakes present a very conservative pattern in terms of seasonality in female reproductive cycles, size at maturity, litter and offspring relative size, and reproductive frequency. The reproductive pattern is similar among the boid species we studied and also similar to pythonids. Females' cycles are non-annual and always seasonal, usually with births occurring mostly in the spring-summer. These snakes show sexual dimorphism occurs in mean body length, head size, spur size and stoutness. In species in which males exhibit combat behavior prior to the mating season, mean body size dimorphism is not present (i.e. Ep. cenchria subspecies). Boid males' reproductive cycles are more variable, being continuous or seasonal depending on the species.

The tadpole of Sphaenorhynchus palustris is described and illustrated from Municipality of Porto Seguro, State of Bahia, Brazil. Sphaenorhynchus tadpoles are very similar, however the tadpole of S. palustris is promptly distinguished from the other already described species by its very long spiracular tube. We also describe the advertisement call of S. palustris, from the same locality. It is a short trill, consisting of 1 to 3 pulsed notes; note duration varies from 0.01 to 0.05 s and note interval varies from 0.15 to 0.19 s; dominant frequency was about 2.62 ± 0.2 kHz. The Atlantic Rain Forest of the southern State of Bahia is one of the well-preserved areas remaining of this fragmented ecosystem; consequently it has unique value for amphibian conservation.

The objectives of this study were to describe the calling sites and identify the reproductive modes for the anuran assemblage in a temporary pond associated to a floodplain system in a Neotropical region in Southern Brazil. In this study we analyzed the influence of temperature, rainfall and hydroperiod on the calling activity of an anuran assemblage. A total of 19 amphibian collections were carried out over a year (from September 2004 to August 2005). Seventeen anuran species of six families were identified: Bufonidae (1), Cycloramphidae (1), Hylidae (6), Leiuperidae (4), Leptodactylidae (4) and Microhylidae (1); however, only fifteen species were observed in calling activity. Three reproductive modes were observed for the community, and the habitat use was temporally and spatially partitioned. 66.7% of the species had the generalized aquatic mode. The anurans presented a prolonged calling activity, and only Chaunus fernandezae presented an explosive pattern. While rainfall for the previous 24 h, air temperature and water depth influenced the calling activity of many anuran species over the studied period, daily rainfall, rainfall for the previous 24 h and water temperature did not influence it.

The defensive behavior of the endemic tropidurid lizard Tropidurus montanus was studied from January to March 2004 at the Serra do Cipó, State of Minas Gerais, southeastern Brazil. This lizards relied on crypsis associated with immobility as the primary strategy of defense to avoid predators. When attacked, locomotor escape was the tactic employed by all recorded individuals. We analyzed the effects of sex on the maximum flight distance and the effects of body size and social context on maximum flight distance and time of flight for males. Males and females did not differ in maximum flight distance. Males with or without a nearby neighbor did not differ in maximum flight distance, but males close to neighbors increased time spent in flight. We found no effect of male body size on maximum flight distance or on the duration of flight. During capture, lizards exhibited threat display, bite, tail waving, tail breakage, thanatosis, forced freeing, body inflation, and cloacal discharge.

Parental care in reptiles has been correlated with cold climates and harsh environments. We investigated whether behavioral patterns indicating parental care occurred in the lizard, Liolaemus elongatus, a viviparous species found on rocky outcrops of the Argentinean Patagonia. Five pregnant females were captured during the austral summer and brought to the laboratory for observations. The females were filmed for short periods of time during six days after the birth of their young. During that time, the mothers and offspring were presented with three predatory stimuli, a Diplolaemus sexcinctus, a male Liolaemus elongatus, and a stuffed hawk, Elanus leucurus. Their responses were recorded as well as the distance between mothers and offspring during the experiments and when no stimuli were presented. Except for one female, mothers constructed burrows in which the neonates were born. Mothers and their offspring occupied the same shelter for the whole period of observation. When presented with predatory stimuli, females seemed to choose between remaining near or on top of the burrow with the young inside, or moving away from it. When the offspring were out of the burrow, a female occasionally covered a neonate, forming a bridge over it, particularly when threatened. Mothers showed individual variations in the way they responded to the different stimuli that were presented.