A new species of the genus Phasmahyla is described from an Atlantic Rain Forest remnant at Serra do Timbó, Municipality of Amargosa, State of Bahia, Brazil. The new species is recognized by its medium size for the genus (snout-vent length 32.4 to 35.8 mm in males); reduced to absent coloration with purple spots on concealed surfaces of arm, forearm, thigh, tibia, tarsus, and digits; male with moderate nuptial pad of minuscule horny asperities on finger I; tympanum distinct only on ventral half; dorsolateral glands well developed; dorsal skin slightly coarse; larval oral disc with distinct anterior and two posterior series of horny teeth; interrupted first posterior series of horny teeth slightly larger than the anterior one. Temporal and spectral parameters of the advertisement call are described for the new species, and for the first time for the genus Phasmahyla.

We investigated calling behavior and call structure for eight species of treefrogs in the genus Scinax, and document noteworthy patterns of interspecific variation that largely reflect habitat and social environment in this report. The five species in the S. ruber clade call in open areas or forest edges near standing water and produce simple calls at relatively high rates and low to moderate frequencies. Species from the S. catharinae clade call from more forested habitats and produce complex, higher frequency calls at relatively low rates. Differences in the range of activity temperatures and habitats among species reflect differences in geographical distribution and spatio-temporal selection of microhabitat during calling. In general, species with high calling rates also had high rates of locomotion during calling activity and were active at warmer temperatures. One exception was S. crospedospilus, which has an extremely high calling rate but exhibits among the lowest rates of locomotion and activity temperatures. Complex calls delivered at lower rates and simple calls produced at high rates represent extremes of the range of calling behavior among these species of Scinax.

The family Anomalepididae which includes four genera and around 15 species has been less studied than all other Scolecophidia. Liotyphlops beui is one of the most collected snake species in São Paulo city. We studied the seasonal and daily surface activity pattern of this fossorial snake. The snakes were collected mainly in rainy and warm periods, indicating a highly seasonal activity. The minimum temperatures explain this pattern more accurately. The decrease in activity of L. beui during the dry and cold season is more pronounced than in any other snake from southeastern Brazil. The morphological and ecological characteristics may explain why this species is collected in lower numbers in the dry season than other snakes from the same region. Activity in L. beui occurs predominantly during the early dark hours, usually between 19:00 and 21:00 h. This short activity period may be determined by light intensity and temperature, although prey and/or predator activity may also influence this activity pattern.

To understand the influence of edge effects on an anuran community within two fragments of different size in an Andean cloud forest, anuran richness, abundance and diversity were studied on transects located at 2, 50, 100 and 200 m from the forest border to the interior. Measures of microhabitat and environmental variables in each sampling site were recorded. Borders with abrupt edges showed the lowest diversity, suggesting that the environmental variables registered demonstrate adverse conditions for the establishment of frogs. The use and the configuration of the adjacent matrix appears to have a strong influence on the edge effect as perceived by the anurans in this area, being much more pronounced across forest borders that abruptly neighbour cattle pasture.

Sixteen adult specimens (six males and ten females) of Acantochelys radiolata from different regions of the state of Rio de Janeiro, Brazil, were monitored in captivity from 1996 to 2000 in order to obtain data on species reproductive biology including breeding season, egg laying, egg incubation, and hatchlings. Mating behaviour was observed between November and March and showed a regular pattern constituted by three conspicuous phases: approximation, persecution, and copulation. Sixteen clutches were found between March and July and twelve eggs were found in natural conditions. Hatches occurred between September and November. Hatchlings showed gular region, anterior and posterior members, tail, and edges of carapace and plastron with reddish blotches resting on a black background. This pattern was modified to an orange tonality in the third month of life.

The advertisement call of Eleutherodactylus johnstonei consists of two adjacent notes (two tones or frequency components). It is, on average, 314 ms in duration, with the first note shorter than the second (86 and 223 ms respectively). The intercall interval is 1.42 s which corresponds to 46,7 calls/min. The dominant frequency of the first note is 1.8 kHz and that of the second note is 3.18 kHz. Both notes contain harmonic series (up to 5 harmonics in the first note and 3 in the second), with narrow bands of constant frequency except for a short and abrupt (38 Hz/ms) upward modulation at the beginning of the second note. Most of the energy of each note is contained in the fundamental band. Spectral characters vary much less than temporal characters, as in other anurans, but variation of spectral characters is amongst the lowest reported so far (~ 1%). There is a weak negative correlation between body mass and the dominant frequency of the call (r = −0.52); therefore call frequency may indicate male size, though to a limited extent. Advertisement calls described here have lower frequencies than those of other localities in the Lesser Antilles and mainland South America. Further research is needed to clarify this issue. Click calls are emitted sporadically in groups of up to four clicks, and are not preceded by introductory notes. Click duration and dominant frequency are, on average, 31 ms and 3.01 kHz, respectively. However, the first and last clicks within a group have lower frequencies than the others. There is substantial variation in the spectral structure of clicks, both within and among groups. All traits have considerable variation (> 10%) except for the frequency of central clicks of a group.

A new species of the genus Physalaemus is described from Serra da Pedra Branca do Araraquara, Municipality of Guaratuba, State of Paraná, southern Brazil. Belonging to the P. olfersii species group, Physalaemus insperatus sp. nov. is closely related to P. aguirrei and presents well-developed vocal sacs expanded laterally to the supratympanic fold, digits very thin, and large inguinal glands.

Demographic studies on crocodilians in subject to strong human disturbance habitats are scarce, particularly in the Neotropical Region. This work provides the first survey data of abundance and population size structure of a neotropical caiman, Caiman latirostris, in disturbed habitats of northwestern Uruguay (30°S, 57°W). We conducted nocturnal surveys in agriculture impoundments (2–116 ha) of the Ñaquiñá and Lenguazo stream basins during summer, from 2001 to 2004. About 81% of impoundments were inhabited by caiman, with relative abundance indices between 2.1 and 4.4 × km⁻¹. Population size structure in the study area was similar throughout the study period; sub-adults from 50 to 119 cm of total length were the most abundant (57–78%), followed by adults (25–33%), and juveniles (6–22%). Relative abundance indices suggested that C. latirostris is not seriously endangered in contrast to previous local reports. The construction of agriculture impoundments in northwestern Uruguay for irrigation of rice and sugar cane seem to have been favored C. latirostris, as indicated by population size structure.