Cinthia A. Brasileiro

Amphibians of an open cerrado fragment in southeastern Brazil

The Cerrado encompasses ca. 2 million km 2 in Brazil. Most Cerrado areas have been greatly disturbed in the past decades. Only 20% of this biome remain undisturbed, and only 1.2% is protected. Knowledge on the biology and diversity of Cerrado amphibian assemblages is still incipient. Here we present natural history information (habitat use and reproductive activity) of 28 species of frogs from the Estacao Ecologica de Itirapina (EEI), and compare the composition of this assemblage with those of other Cerrado areas, other open areas, and a few forest areas throughout Brazil. We demonstrate that the Itirapina assemblage is more similar to those of other open areas than to those of forests, even when the latter are geographically closer. Six species occurred in the gallery forest at varying levels of dependence (three independent, two semidependent, and one totally dependent) while all other species occurred exclusively in open areas. For most species at EEI, reproduction was strongly synchronized with the onset of the rainy season, with the exception of Hypsiboas lundii, which called throughout the year, and Proceratophrys sp. which started calling prior to the beginning of the rainy season. The spatial and temporal patterns observed in this assemblage seem to reflect both ecological (e. g. hydroperiod of water bodies) and historical factors (e. g. early breeding in leptodactylids, late breeding in hylids, both phylogenetically constrained).

A New Island Species of Scinax (Anura; Hylidae) from Southeastern Brazil

Abstract A new species of hylid frog, from the genus Scinax, is described from Ilha de Porcos Pequena at the southern coast of São Paulo State, southeastern Brazil. The new species belongs to the Scinax perpusillus species group and is diagnosed by the following set of characters: moderate-size (males 16.2–18.8 mm SVL, female 18.8–20.6 mm SVL); canthus rostralis distinct and well defined; V-shaped depression between nostrils; eyes protruding and prominent, glandular skin surface of legs. This new species is found only on Ilha de Porcos Pequena, an island of approximately 24 ha and, therefore, is threatened because of restricted range size and susceptibility to habitat modification.

Breeding biology of Physalaemus centralis Bokermann, 1962 (Anura: Leptodactylidae) in southeastern Brazil

Physalaemus centralis is widely distributed in areas of cerrado vegetation in South America. Here we describe the temporal variation in activity and explore eventual effects of climatic conditions on activity, calling sites, territorial behaviour; courtship behaviour, egg clutches and tadpole development of P. centralis in southeastern Brazil. Field observations were made from January 1996 to February 1997. Vocalisations and reproductive activity were restricted to the rainy season, with a peak of activity in October. The number of calling males was significantly correlated with relative humidity, mean air temperature, and air pressure values of the previous day. Courtship is simple and did not include any physical contact before amplexus; furthermore, females seem to choose their mates. Amplectant pairs were observed from mid‐October to mid‐December. Most foam nests observed were anchored within the vegetation. The number of eggs in the foam nests ranged from 1549 to 2405. Tadpoles were mainly found in shallow parts of the water from October to mid‐January. The reproductive biology of P. centralis is similar to that of closely related species of the P. cuvieri group, suggesting conservatism in this lineage.

The reproductive ecology of Leptodactylus fuscus (Anura, Leptodactylidae): new data from natural temporary ponds in the Brazilian Cerrado and a review throughout its distribution

Recent studies indicate that populations historically called Leptodactylus fuscus (Schneider, 1799) comprise at least three well‐differentiated lineages. Herein, we describe the reproductive ecology of a southeastern clade population of L. fuscus, and review the characters of the reproductive ecology for several populations of the northern and southeastern clades. Most reproductive activity occurred in December and January, which coincided with the highest rainfall period. Males had an aggregated spatial distribution in the central area of the ponds. Three courtship interactions were observed. A female was observed closing the entrance to a burrow with moist sand after oviposition. This behaviour is described for the first time in L. fuscus. The review of the reproductive biology of the northern and southeastern clades indicates a relatively high plasticity in L. fuscus. Furthermore, the results corroborate the suggestion, based on molecular data, that the northern and southeastern clades of L. fuscus represent distinct evolutionary units.

Anurans, Northern Tocantins River Basin, states of Tocantins and Maranhão, Brazil

This study presents a list of anurans in the northern region of the Tocantins River Basin (states of Tocantins and Maranhao), with information regarding seasonality, habitat, and microhabitat. We recorded 38 species in 15 genera and seven families. Most species (47 %) occurred exclusively in open areas and only 11 % of the species were found in forest habitats. Around 82 % of species were observed in ponds and only 7 % occurred in streams. Regarding seasonality, 54 % were observed both in the rainy and dry seasons. The northern area of the Cerrado has being rapidly converted in monocultures and information on its anuran fauna is limited. Additional information on its biodiversity is neeed in order to provide the framework for conservation strategies.

Dimorfismo sexual, uso do ambiente e abundância sazonal de Elachistocleis cf. ovalis (Anura: Microhylidae) em um remanescente de Cerrado no estado de São Paulo, sudeste do Brasil

Thome, M.T.C. & Brasileiro, C.A. Sexual Dimorphism, habitat use and seasonal abundance of Elachistocleis cf. ovalis (Anura: Microhylidae) in a Cerrado remnant of Sao Paulo state, southeastern Brazil. Biota Neotrop. Jan/Apr 2007 vol. 7, no. 1 http://www.biotaneotropica.org.br/v7n1/pt/abstract?article+bn00307012007 ISSN 1676-0603. Elachistocleis ovalis is a species presenting taxonomical problems and wide distribution throughout South America. We provide information on sexual dimorphism, calling site, habitat use and seasonal abundance of E. cf. ovalis in a preserved Cerrado area in Sao Paulo State, southeastern Brazil. Sampling was carried out primarily with pitfall traps. Traps were placed in areas characterized by three different physiognomies: campo sujo, campo cerrado, and gallery forest edge. We found sexual dimorphism, with females being larger than males. Similar dimorphism has already been documented for other populations and congeneric species. The calling site of males was also in agreement with the literature on other populations and species. Habitat use was different among the three environments, with higher abundance in gallery forest edges. This population showed a clear pattern of seasonal activity, in which abundance was higher during rainy seasons, as well as other Cerrrado anuran species. Abundance was related to relative air humidity and maximum temperature, two variables whose influence on anurans has already been documented. We found no variation in the abundance patterns of the population between the two years in which samples were carried out.

A NEW AND THREATENED ISLAND-DWELLING SPECIES OF CYCLORAMPHUS (ANURA: CYCLORAMPHIDAE) FROM SOUTHEASTERN BRAZIL

We describe a new species of Cycloramphus of the eleutherodactylus group from the Ilha dos Alcatrazes, southeastern Brazil, with descriptions of advertisement and territorial calls and notes on natural history. Additionally, we describe the advertisement and territorial calls of C. eleutherodactylus. The new species is diagnosed by the following set of characters: snout truncate in lateral and dorsal views; head wider than long; eyes protruding; tibia shorter than thigh; and distinct advertisement call. The new species is known from a single population on the Ilha dos Alcatrazes, a 149 ha island about 35 km off São Paulo State coast where these frogs are scattered in a small valley. The very restricted range of the new species of Cycloramphus and the declining quality of its habitat qualify this frog as critically endangered.

Feeding Ecology of Thoropa taophora (Anura: Cycloramphidae) on a Rocky Seashore in Southeastern Brazil

ABSTRACT. The rock frog (Thoropa taophora) dwells from rocky seashores to rocky outcrops within the Atlantic rainforest on coastal areas of the state of São Paulo, southeastern Brazil. In this study, we provide data on the food habits of a rock frog population focusing on ontogenetic, sexual, and seasonal variation. The study was based on the examination of 356 individuals (154 adults, 82 juveniles and 120 froglets). A total of 26 invertebrate types were found in the diet of T. taophora. The commonest prey types in the three size classes (adults, juveniles and froglets) of rock frogs were ants, both in frequency and number. Prey composition differed significantly among size classes, except for beetles and spiders. Prey composition of males and females also differed significantly: females had a high proportion of marine isopods, caddisfly nymphs, and orthopterans in the diet, whereas males had a high proportion of ants and caterpillars. Seasonal changes in diet (all significant) in the three size classes include froglets eating more springtails and less mites in the dry season, juveniles eating more marine isopods during the wet season (similar difference for adult males), and adult females eating more ants during the wet season.

Chromosome evolution in three Brazilian Leptodactylus species (Anura, Leptodactylidae), with phylogenetic considerations

Karyotypic analyses on three species of the Leptodactylus from Brazil showed 2n=24 in L. cf. marmoratus, 2n=23 in Leptodactylus sp. (aff. bokermanni), and 2n=26 in L. hylaedactylus, with distinct numbers of bi and uni-armed chromosomes. Leptodactylus cf. marmoratus presented a variation as regard to the morphology of pair 12. All specimens of L. cf. marmoratus had Ag-NOR in pair 6, confirmed by FISH, but the sample from one of the localities presented additional Ag-NOR, in one of the chromosomes 8. In Leptodactylus sp. (aff. bokermanni) and L. hylaedactylus the chromosome pairs bearing Ag-NOR are 11 and 7, respectively. The C banding patterns are predominantly centromeric, but only in L. marmoratus this heterochromatin appeared very brilliant with DAPI. On the other hand, bright labelling was noticed with CMA(3) in the three species, on the Ag-NOR site. The data obtained here are in accordance with the proposed phylogeny to the genus, and the chromosomal analyses in these Leptodactylus showed that the karyotype evolution was based mainly in centric fusion and pericentric inversion.

A New Species of Physalaemus from Central Brazil (Anura: Leptodactylidae)

Abstract:  We describe a new species of Physalaemus from central Brazil. It is characterized by the following combination of traits: medium-sized; snout subelliptical in dorsal view, varying between rounded and protruding in lateral view; head longer than wide; snout long; dorsolateral fold present; small inguinal gland associated with dark ocellus present; tarsal tubercle present; poorly developed tarsal fold present and supernumerary tubercles on feet absent. The advertisement call is a single note with eight harmonics lasting 0.7–1.0 s in duration and emitted at intervals of 0.6–5.8 s. The dominant frequency varies from 1.9 to 3.1 kHz. The occurrence of the new species is in open habitats (disturbed or preserved) in central Brazil.