Ricardo J. Sawaya

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).

Diversity and evolution of macrohabitat use, body size and morphology in a monophyletic group of Neotropical pitvipers (Bothrops)

The Neotropical pitviper genus Bothrops comprises about 40 species, which occur in all main ecosystems of cis-Andean South America. We explored the relationships of body size and form (tail length and stoutness) with macrohabitat use in 20 forms of Bothrops. Semi-arboreal habits appeared only in forest forms. Semiarboreals are significantly more slender and have longer tails than terrestrials; body size is not significantly different between terrestrials and semi-arboreals. Within Bothrops, independent contrasts for macrohabitat use were significantly correlated with contrasts of tail size (positively) and stoutness (negatively); thus, the more arboreal the species, the longer its tail and the more slender its body. Contrasts of adult body size seems to remain constant over the lower range of macrohabitat use, but to decrease in species of Bothrops which are more arboreal. Reconstructions of character states indicate that: (1) the ancestor of Bothrops was a small, stout, terrestrial species; (2) semi-arboreal habits appeared one to three times in the genus; (3) a decrease in stoutness and an increase in tail length occurred along with an increase in arboreality in some clades. Although macrohabitat use seems to be important in determining body form in Bothrops, our results also indicate that tail size, stoutness and body size may also be affected by selective agents other than macrohabitat use. The selective agents responsible for the shifts in macrohabitat use in Bothrops are still uncertain, although they may have included prey availability and/or predation pressure. The plasticity of macrohabitat use, morphology and body size described in this study may have been key features that facilitated the highly successful ecological diversification of Bothrops in South America.

Composition and natural history of a Cerrado snake assemblage at Itirapina, São Paulo state, southeastern Brazil

As taxocenoses de serpentes neotropicais apresenta m alta riqueza de especies e estruturas complexas. O Cerrado e o segundo maior bioma do Brasil e foi incluido entre os 25 hotspots globais de biodiversidade. No sudeste do Brasil, as areas remanescentes de Cerrado tem sofrido intensa destruicao, e atualmente restam menos de 2% da vegetacao natural de Cerrado no estado de Sao Paulo. Praticamente nenhum estudo detalhado sobre serpentes do Cerrado foi realizado nesta regiao. A regiao de Itirapina apresenta um dos ultimos remanescentes bem preservados de cerrado aberto no estado de Sao Paulo. Nosso objetivo neste trabalho foi o estudo da historia natural e composicao das serpentes de Cerrado da regiao de Itirapina. Nos realizamos uma amostragem de campo extensiva combinando seis metodos de amostragem na Estacao Ecologica de Itirapina e areas alteradas de Cerrado nas proximidades (municipios de Itirapina e Brotas), em 101 viagens durante 43 meses, entre setembro de 1998 e marco de 2002, o que correspondeu a 446 dias de amostragem de campo. Tambem coletamos dados adicionais a partir de especimes de colecoes cientificas. Apresentamos dados sobre tamanho, abundância geral, uso do ambiente e substrato, atividade diaria e sazonal, dieta, reproducao e defesa. Tambem comparamos a taxocenose de serpentes de Itirapina com nove taxocenoses de serpentes do Brasil, incluindo a Amazonia, Mata Atlântica, Cerrado e outras formacoes abertas. Registramos na regiao de Itirapina 36 especies de serpentes entre 755 individuos encontrados no campo e seis registros de colecoes cientificas e literatura, pertencentes a 25 generos de cinco familias. As comparacoes entre taxocenoses indicam que o Cerrado apresenta uma identidade propria em relacao a composicao de especies de serpentes. Apesar de limitada a um pequeno fragmento (cerca de 2.300 ha), a Estacao Ecologica de Itirapina apresenta fisionomias conservadas e representativas de Cerrado, que abrigam uma fauna de serpentes rica e tipica do Cerrado. A ocorrencia de algumas especies apenas no interior da reserva tambem indica que a Estacao Ecologica de Itirapina e de importância fundamental para a manutencao da biodiversidade do Cerrado.Neotropical snake assemblages present high species richness and complex structures. The Cerrado is the second largest biome in Brazil, and was included among the 25 Worlds biodiversity hotspots. In southeastern Brazil, the remnant Cerrado areas have suffered intense destruction, and presently less than 2% of Cerrado natural vegetation remain in Sao Paulo state. Virtually no detailed study on Cerrado snakes was carried out in this region. The Itirapina region has one of the last well preserved remnants of open cerrado in Sao Paulo state. Our purpose in this work was the study of natural history and composition of the Cerrado snakes of Itirapina region. We performed an extensive field sampling combining six sampling methods in Estacao Ecologica de Itirapina and disturbed Cerrado areas in its surroundings (municipalities of Itirapina and Brotas), during 101 trips throughout 43 months, between September 1998 and March 2002, corresponding to 446 days of field sampling. We also collected additional data from museum specimens housed in scientific collections. We present data on size, general abundance, habitat and macrohabitat use, daily and seasonal activity, feeding, reproduction, and defense. We also compared the Itirapina snake assemblage with nine snake assemblages of Brazil, from Amazonia, Atlantic Forest, Cerrado, and other open habitats. We recorded a total of 36 snake species among 755 individuals found in the field and six records from scientific collections and literature, belonging to 25 genera and five families. The snake assemblage comparisons indicate that the Cerrado has its own identity regarding the snake composition. Although small (about 2,300 ha), the Estacao Ecologica de Itirapina encompasses well preserved and representative Cerrado physiognomic forms, which harbors a rich and typical Cerrado snake fauna. The occurrence of some species only inside the reserve also indicates that the Estacao Ecologica de Itirapina is of fundamental importance to the maintenance of Cerrado biodiversity.

Herpetofauna dos remanescentes de Mata Atlântica da região de Tapiraí e Piedade, SP, sudeste do Brasil

We present the species list of amphibians and reptiles registered in continuous and fragmented Atlantic Forest remnants at Tapirai and Piedade municipalities, Atlantic Plateau of Sao Paulo, Brazil. We sampled 21 localities, 15 located within unprotetcted forest fragments and six located at Parque Estadual do Jurupara, the single legal protected area in this region and surroundings. We recorded 47 anurans, one gymnophiona, seven lizards, one amphisbenian, 46 snakes, and one turtle. The specimes were captured by pitfall traps with drift fences, visual and auditive surveys, incidental encounters, local collectors, and, for snakes, by recording scientific collection records. Sampling methods were effective in documenting local herpetofauna, showing the adequacy of the use of complementary methods. Forest remnants at Tapirai and Piedade have typical species of Atlantic Forest areas, and show higher species richness in comparison with other lists in the Atlantic Plateau. The presence of species known from few localities, or present in threatened species lists, shows that the Atlantic Forest remnants in this region need conservation attention. Although still harboring high herpetofaunal diversity, the remnants are threatened by the effects of forest fragmentation.

Composição e diversidade de anfíbios anuros em dois ambientes de Mata Atlântica no Parque Estadual Carlos Botelho, São Paulo, sudeste do Brasil

Moraes, R.A. de, Sawaya, R.J. & Barrela, W. Composition and diversity of A nuran Amphibians in two Atlantic Forest environments in Southeastern Brazil, Parque Estadual Carlos Botelho, Sao Paulo, Brazil. Biota Neotrop. May/Aug 2007 vol. 7, no. 2 http://www.biotaneotropica.org.br/v7n2/pt/abstract?article+bn0030 7022007. ISSN 1676-0603. The Atlantic Forest is characterized by its high species richness and endemism, and is one of the 25 hotspots of biodiversity around the world. We present information on composition and diversity of anuran amphibians in two environments with different degrees of disturbance in Parque Estadual Carlos Botelho, Sao Paulo state, an area of Atlantic Rain Forest in southeastern Brazil. We sampled an artificial pond in a disturbed area and a pond in a preserved area by audio sampling and incidental encounters, in 36 nights in each habitat. We compared the species composition, richness, dominance, and relative abundance between the two habitats. Despite distant only ca. 400 m, we recorded only two species in common between the two habitats. We recorded in the disturbed area 10 species (N = 518) with 46.7% of dominance of Hypsiboas albopunctatus; and in the preserved habitat we recorded 11 species (N = 656) with 36.0% of dominance of Dendropsophus giesleri. Richness was not significantly different between the habitats. The estimated dominance by rarefaction in the preserved habitat was significantly lower than that in the disturbed habitat. The capability of some species populations in colonizing the disturbed habitat, the distinct physiological tolerance among species, and the dependence on specific microhabitats for reproduction are possible factors related to the observed patterns. We suggest that additional alterations of the Atlantic Forest cover inside the reserve might result in a decrease of alpha-diversity by eliminating forest dependent species, as well as a consequently increase in beta-diversity by the colonization of open area species that are ecologically more generalist. The slightly higher richness and mainly lower dominance observed in the preserved area indicate it is the habitat with higher species diversity. Thus, the presence of old-growth and/or conserved forests in the reserve is essential to maintain the local anuran diversity.

Anfíbios do Estado de São Paulo, Brasil: conhecimento atual e perspectivas

The last list of species of the state of Sao Paulo State was updated and totaled 236 species of amphibians, 230 of which are anurans and six are caecilians. Bokermannohyla gouveai and Sphaenorhynchus surdus were removed from this list, because they did not occur in the State of Sao Paulo. The number of anuran species recorded comprise 27% of the species richness of the country and an increase by 31% in the number of species recorded for the state since 1998. Thus, despite the State of Sao Paulo be the Brazilian region where the anurans have been most studied, these data show that the number of known species tends to increase in the next years. We have identified two major geographical gaps of inventory: the southwest of the state, especially in the Paranapanema river basin and the northeast region, mainly at the border between the States of Minas Gerais and Sao Paulo. Although both have been sampled recently, information is still lacking. The current state of knowledge and perspectives in the areas such as taxonomy, systematics, ecology and conservation are evaluated.

Anfíbios Anuros do Parque Estadual das Furnas do Bom Jesus, sudeste do Brasil, e suas relações com outras taxocenoses no Brasil

We present the 24 anuran species occuring in Parque Estadual das Furnas do Bom Jesus (PEFBJ), municipality of Pedregulho, Sao Paulo state, southeastern Brazil. Barycholos ternetzi, Rhinella rubescens, Scinax canastrensis, and Phyllomedusa ayeaye correspond to new records to the Sao Paulo state species list, the latter species considered as threatened in IBAMA and IUCN lists. In order to characterize the PEFBJ anuran assemblage we compare its species composition with 66 localities from different biomes in Brazil. The 67 assemblages were ordinated and grouped by Principal Coordinates Analysis (ACOP) and Cluster Analysis. The multivariate analysis allowed the identification of four groups: one from Amazonian forest assemblages; two from Atlantic forest assemblages, being one consisting of dense Atlantic rain forest of Bahia, Espirito Santo states and its transitions with seasonal semideciduous forests (Minas Gerais state), and the other one consisting of localities of dense Atlantic rain forest of Rio de Janeiro, Sao Paulo, Parana states and its transitions with araucaria rain forest (Atlantic rain forest with Araucaria angustifolia), seasonal semideciduous forests, and Pampas Biome assemblages; assemblages from more open physiognomies, as Caatinga (semiarid steppe of Northeast Brazil), Cerrado (Brazilian savanna), Pantanal (Brazilian wetlands), and the Atlantic forest (seasonal semideciduous forests) were included in the fourth group. The faunistic groups obtained indicate that species composition of the 67 localities are strongly related to the vegetation types where they occur. The great diversity observed among the physiognomic vegetation types could be related to the topographic and climatic variations found in the different biomes considered in our analysis (Amazon, Caatinga, Cerrado, Atlantic forest, Pampas and Pantanal). The anuran assemblage of PEFBJ was grouped among the biomes with open phytophysiognomies (fourth group), showing great similarity to the faunas of Cerrado and semideciduous forests in the Atlantic forest Biome of Sao Paulo state.

Interaction between breeding habitat and elevation affects prevalence but not infection intensity of Batrachochytrium dendrobatidis in Brazilian anuran assemblages.

Chytridiomycosis, an infectious disease of amphibians, is caused by the fungus Batrachochytrium dendrobatidis (Bd) and has been linked to declining amphibian populations worldwide. The susceptibility of amphibians to chytridiomycosis-induced population declines is potentially influenced by many factors, including environmental characteristics, differences among host species and the growth of the pathogen itself. We investigated the effects of elevation and breeding habitat on Bd prevalence and individual infection intensity (zoospore loads) in 3 anuran assemblages of the Atlantic Coastal Forest of Brazil. Bd infection intensity was strongly influenced by elevation and breeding habitat, but we found no evidence of an interaction between those 2 variables in explaining the number of zoospores sampled from individual frogs. In contrast, Bd infection odds were predicted by elevation and by an interaction between elevation and breeding habitat, such that frogs had a higher probability of Bd infection in lotic habitats at low elevations. Our results indicate that Bd persists across a wide variety of habitats and elevations in the Atlantic Coastal Forest. Prevalence and infection intensity of Bd are highest at high elevations where overall environmental conditions for Bd are most favorable. In addition, at low elevations amphibian host habitat choice is also an important determinant of infection. Our study highlights the need to investigate interacting variables of host ecology and the environment simultaneously.

Os répteis do município de São Paulo: diversidade e ecologia da fauna pretérita e atual

The reptile fauna in the municipality of Sao Paulo is well sampled due to intensive collection in the last 100 years. In the present work we provide a checklist of reptile species in Sao Paulo municipality based on preserved specimens in scientific collections. The reptile fauna was also characterized by three ecological parameters: habitat use, substrate use, and diet. We recorded a total of 97 reptile species (two turtles, one crocodilian, 19 lizards, seven amphisbaenians, and 68 snakes). Approximately 70% of the lizards and 40% of the snakes are typical of forest habitats of the Serra do Mar mountain range. Other squamates are typical of open formations that occur mainly on inland Cerrado habitats. All turtles and the crocodilian are associated to riparian habitats. Approximately 63% of the lizards are predominantly terrestrial, and the remaining species are arboreal. Most species of snakes are terrestrial (38%) or subterranean/criptozoic (25%) whereas a smaller proportion are arboreal (18%) or aquatic (9%). Lizards feed upon arthropods. Almost 50% of the snake species are specialized or feed mainly upon anuran amphibians. Other important items consumed by snakes are mammals (24%), lizards (18%), subterranean vertebrates (10%), and invertebrates (earthworms, mollusks and arthropods; 15%). A total of 51 reptile species have not been recorded for the last six years. Probably many of these species are extinct in the region due the intense local urbanization and habitat loss. The survey of species collected in Sao Paulo municipality and received in the Instituto Butantan in recent years allowed the identification of 10 lizards at least 42 snake species already occurring in the region. The high species richness of the original fauna seems related to the geographic location of the municipality, in a contact zone between forested areas of the Atlantic Forest (ombrophilous forest) and open formations (savannas, high-altitude grassland). Thus, the original habitat composition probably allowed sympatry among different species pools typical of both open and forested formations. The extant snake fauna recorded in the last three years indicates a higher loss of the species in open formations when compared to the forested areas.

New Species of Brachycephalus (Anura: Brachycephalidae) from the Atlantic Rain Forest in São Paulo State, Southeastern Brazil

Abstract A new species of brachycephalid frog is described from São Luís do Paraitinga, in the Atlantic Rain Forest of São Paulo State, southeastern Brazil. The new species is characterized by male SVL  =  10.8–12.1 and female SVL  =  12.6–14.0 mm; and general color orange with dorsal reddish irregular markings, lateral surfaces with small dark brown spots, and belly with brownish spots and small dots. Comparisons with other brachycephalid species and osteological data are provided.