No abstract

Submetido em 15/03/2010 Aceito para publicação em 10/04/2010 Resumo Répteis e anfíbios de uma região pouco conhecida do sudeste da Amazônia. Amazônia é a maior

We provide a list of amphibians, lizards, chelonians, and snakes collected during a 30-day expedition to the Serra da Capivara National Park, Piauí State, Brazil. Thirty-seven pitfall trap arrays composed of 4 buckets each, along with glue traps, funnel traps, and haphazard searches, were used to sample the herpetofaunal diversity. We recorded 17 species of lizards, 1 caecilian, 1 chelonian, 7 frogs, and 11 snakes. Rarefaction curves suggest that local biodiversity is still underestimated. An atypical drought during the period of study may have contributed to lower captures of certain groups, especially amphibians and snakes. The presence of water-dependent and forest-dependent species within local canyons (“Boqueirões”) suggests that these areas harbor faunas associated with relictual rainforest fragments and need to be better studied and managed accordingly.

Despite an increase in studies focusing on snake ecology and composition in the northeastern Atlantic Forest, several poorly studied sites and environments remain. The aim of this study was to assess species richness and natural history attributes of the snakes of an assemblage in the Restinga, Tabuleiro and Forest environments of the Atlantic Forest of the south coast of Paraíba, northeastern Brazil. A total of 151 individuals of 27 species, 23 genera, and six families of snakes were found. The most effective sampling methods were time-constrained searches and incidental encounters. Species sampled most frequently were the blindsnake Epictiaborapeliotes, the Boa Constrictor Boaconstrictor, the Brown Vinesnake Oxybelisaeneus, and the Brazilian False Coral Snake Oxyrhopustrigeminus. The snake fauna is characterized mainly by terrestrial species found in open-area environments of Restinga and Tabuleiro, and with most species feeding on amphibians and small mammals. The rarefaction curve did not reach the asymptote and new species should be recorded for south coast of Paraíba in future studies. Despite the richness and composition of snakes of the south coast being similar to other areas in the state, there is a lack of some species typically linked to forests, and this is probably because of the high level of deforestation that the south area of the state has suffered.

The main factors that structure Neotropical animal communities have been the subject of discussion in ecology communities. We used a set of null models to investigate the existence of structure in snake communities from the Cerrado in Central Brazil in relation to the co-occurrence of species and guilds concerning specific resources. We used fragments (conservation units) inside the Distrito Federal and neighbor municipalities. In spite of recent human colonization in the region from the end of the 1950's, intense habitat modification and fragmentation has taken place. Sixty three snake species are present in the Distrito Federal. Co-occurrence analysis of species and guilds associated to snake diets and habitats suggested a lack of organization. The homogeneity of habitats in Central Brazil and the minor importance of ecological effects can lead to random arrangement.Keywords: snakes, Central Brazil, community, null models, Cerrado. Existem padrões de coocorrência que estruturam comunidades de serpentes no Brasil Central? ResumoOs processos que levam à estruturação de comunidades animais neotropicais têm sido sujeito de ampla discussão em ecologia de comunidades. Usou-se um conjunto de modelos nulos para investigar a existência de estrutura em comunidades de serpentes presentes no Cerrado do Brasil Central, em relação à coocorrência de espécies e de guildas relacionadas a recursos específicos. As localidades utilizadas para as análises representam fragmentos de habitats dentro do Distrito Federal e em municípios vizinhos. Apesar da recente colonização humana da região, datada para o final da década de 50, a intensidade da modificação e fragmentação dos habitats no Brasil Central têm sido enorme. Sessenta e três espécies de serpentes estão presentes no Distrito Federal. As análises dos padrões de coocorrência tanto para as espécies quanto para guildas relativas à dieta e ao uso do ambiente sugeriram ausência de organização. A homogeneidade dos ambientes no Brasil Central e a baixa importância de efeitos ecológicos podem levar ao arranjo randômico.