Background/Question/Methods Most anurans undergo a major ontogenetic niche shift, as tadpoles the... more Background/Question/Methods Most anurans undergo a major ontogenetic niche shift, as tadpoles they occupy aquatic habitats and then terrestrial habitats as adults. Thus, considering that habitats occupied by tadpoles are determined by the breeding choices of adults, we hypothesized that: 1) environmental filters have a stronger effect on adults than on tadpoles; 2) adult traits (e.g., presence of adhesive disc, reproductive behavior) are more associated with extrinsic characteristics of breeding habitats (e.g., canopy cover), and tadpole traits (e.g., body size, fin height) are more associated with intrinsic characteristics (e.g., aquatic vegetation); 3) phylogeny is a proxy for trait diversification in communities of both tadpoles and adults. We tested whether phylogenetic and trait diversification were different than expected by chance across breeding habitats along the ontogenetic gradient. We also investigated the relationship between phylogeny, morphological and life-history tr...
Apresentamos as 24 espécies de anfíbios anuros que ocorrem no Parque Estadual das Furnas do Bom J... more Apresentamos as 24 espécies de anfíbios anuros que ocorrem no Parque Estadual das Furnas do Bom Jesus (PEFBJ), Pedregulho, São Paulo, sudeste do Brasil. Barycholos ternetzi, Rhinella rubescens, Scinax canastrensis e Phyllomedusa ayeaye correspondem a novos registros para o estado de São Paulo, sendo a última espécie incluída na lista de espécies ameaçadas de extinção do Ibama e IUCN. Para caracterizar a taxocenose de anuros do PEFBJ, comparamos sua composição de espécies com a de outras 66 localidades em diversos biomas e fitofisionomias do Brasil. As 67 taxocenoses foram ordenadas e agrupadas por meio de uma Análise de Coordenadas Principais (ACOP) e uma Análise de Agrupamento (Cluster Analysis). As análises multivariadas permitiram a identificação de quatro grupos: um de taxocenoses amazônicas; dois de taxocenoses de Mata Atlântica, sendo um composto por floresta ombrófila densa dos estados da Bahia e Espírito Santo e sua transição com a floresta estacional semidecidual (Minas Ger...
Boletin de la Asociación Herpetológica Española, 2000
Resumen: Se presenta una nueva localidad de Ia tortuga Phrynops vanderhaegei en Brasil sudorienta... more Resumen: Se presenta una nueva localidad de Ia tortuga Phrynops vanderhaegei en Brasil sudoriental. Los especimenes se localizaron en un area de savana (cerrado) con pequefios tramos de bosque ripario. Se cementa brevemente el habitat circundante. El hallazgo de esta poblaci6n aislada puede ser importante en Ia conservaci6n de Ia especie ya que indica que otras poblaciones podrian sobrevivir y reproducirse en pequefios fragmentos con vegetaci6n bien conservada. Key words: Brazil, Chelidae, conservation, Phrynops ...
We evaluated the use of oral deformities as reliable proxies for determining Batrachochytrium den... more We evaluated the use of oral deformities as reliable proxies for determining Batrachochytrium dendrobatidis (Bd) infection in tadpoles of six anuran species of the Atlantic Forest in southeastern Brazil. We examined oral discs of 2156 tadpoles of six species of anurans collected in 2016: Aplastodiscus albosignatus, Boana albopunctata, Boana faber, Scinax hayii, Crossodactylus caramaschii, and Physalaemus cuvieri. Three oral deformities were recognized: lack of keratinization only in upper and/or lower jaw sheaths, lack of keratinization only in upper or lower tooth rows, and both deformities together. A subsample composed of all the individuals possessing oral deformities (N = 195) plus randomly selected individuals without oral deformities (N = 184) were tested for Bd via qPCR. Oral deformities were observed in all six species, but only five were infected with Bd. Since we found that dekeratinization of tooth rows was not associated with the presence of Bd in any of the studied spe...
Resumo: As taxocenoses de serpentes neotropicais apresentam alta riqueza de espécies e estruturas... more Resumo: As taxocenoses de serpentes neotropicais apresentam alta riqueza de espécies e estruturas complexas. O Cerrado é o segundo maior bioma do Brasil e foi incluído entre os 25 hotspots globais de biodiversidade. No sudeste do Brasil, as áreas remanescentes de Cerrado têm sofrido intensa destruição, e atualmente restam menos de 2% da vegetação natural de Cerrado no estado de São Paulo. Praticamente nenhum estudo detalhado sobre serpentes do Cerrado foi realizado nesta região. A região de Itirapina apresenta um dos ...
We evaluated the use of oral deformities as reliable proxies for determining Batrachochy-trium de... more We evaluated the use of oral deformities as reliable proxies for determining Batrachochy-trium dendrobatidis (Bd) infection in tadpoles of six anuran species of the Atlantic Forest in southeastern Brazil. We examined oral discs of 2156 tadpoles of six species of anurans collected in 2016: Aplastodiscus albosignatus, Boana albopunctata, Boana faber, Scinax hayii, Crossodactylus caramaschii, and Physalaemus cuvieri. Three oral deformities were recognized: lack of keratinization only in upper and/or lower jaw sheaths, lack of keratinization only in upper or lower tooth rows, and both deformities together. A subsample composed of all the individuals possessing oral deformities (N = 195) plus randomly selected individuals without oral deformities (N = 184) were tested for Bd via qPCR. Oral deformities were observed in all six species, but only five were infected with Bd. Since we found that dekerati-nization of tooth rows was not associated with the presence of Bd in any of the studied species we used a new proxy (jaw sheaths dekeratinization with or without dekeratinization in tooth rows: JSD-proxy) for Bd detection. Our results showed a nonrandom relationship between Bd infection and JSD-proxy in three species of the family Hylidae. However, the use of JSD-proxy for Bd detection in these species resulted in up to 30.8% false positives and up to 29.3% false negatives. The use of the JSD-proxy in species for which no relationship was found reached 100% of false positives. We conclude that the use of oral dekeratini-zation as a generalized proxy for Bd detection in tadpoles should not be used as a single diagnosis technique.
Polygyny is a common mating system in lizards. In polygynous species, males usually display statu... more Polygyny is a common mating system in lizards. In polygynous species, males usually display status badges and use weaponry to prevent reproductive access of competitors to mates. Such secondary sexual traits are frequently linked to signalling costs and the handicap principle is widely used to explain the potential reduction of fitness components. Here, we (1) evaluate the allometric relationship of two known secondary sexual traits with body size: head width (a weapon) and the total coloured lateral area (an ornament), (2) assess the effects of such traits on male and female survival probabilities and (3) evaluate patterns of linear and quadratic selection of both traits for the whiptail lizard Cnemidophorus cf. ocellifer. We detected evidence of sexual dimorphism in both traits, but contrary to our expectations , both sexes presented hyperallometric growth of both weapon size and badge size. We found no support for the handicap principle since no detrimental effects of secondary sexual traits were found on individual survival probability. Furthermore, no evidence of directional selection, neither stabilizing nor disruptive selection was found. The costs of faking signals in male animal contests could maintain the honesty, as previously suggested.
The State of São Paulo is one of the most studied regions of Brazil in regard to amphibian specie... more The State of São Paulo is one of the most studied regions of Brazil in regard to amphibian species richness and distribution. However, we still do not have a list of species for the State. Therefore, we present here a list including 231 species of amphibians (225 anurans and six caecilians), of which 27 are endemic. We present data about previous and current taxonomists and speculate about future prospects in the study and conservation of amphibian biodiversity in São Paulo State.
Most miniaturized froglets of the genus Brachycephalus occur in isolation in slopes of mountain r... more Most miniaturized froglets of the genus Brachycephalus occur in isolation in slopes of mountain ranges at elevations varying from 600 to 1,800 m in the Atlantic Forest of eastern Brazil. For organisms such as Bracycephalus with spatially discontinuous distributions, a fundamental task is to determine whether observed patterns of variation are consistent with geographic differentiation among allopatric populations within a single species or are suggestive of a potential species boundary. We address this problem by focusing on continental and island population samples potentially assignable to Brachycephalus nodoterga (Anura: Brachycephalidae) from the perspective of variation in qualitative and quantitative morphological traits and DNA sequences. Population samples from continental and island populations share color characteristics, qualitative traits, and multivariate patterns of variation and covariation in cranial metric traits. Comparative analysis of DNA sequences showed the magnitude of molecular distances between B. nodoterga and Brachycephalus ephippium to be 1 order of magnitude larger than molecular distances within B. nodoterga and B. ephippium. We interpret the combined morphological and molecular evidence to indicate that continental and island population samples examined here are conspecific. Therefore, by defining species boundaries for B. nodoterga, we also established minimal estimates of its distribution range.
RESUMO A última lista de espécies do Estado de São Paulo foi atualizada, totalizando 236 espécies... more RESUMO A última lista de espécies do Estado de São Paulo foi atualizada, totalizando 236 espécies de anfíbios, das quais 230 são anuros e seis são Gymnophiona. Foram removidos da lista Bokermannohyla gouveai e Sphaenorhynchus surdus por não ocorrerem no Estado de São Paulo. O número de espécies de anuros registrado representa 27% da riqueza de espécies do país e um aumento de 31% em relação ao número de espécies registradas para o Estado em 1998, demonstrando que, a despeito do Estado de São Paulo ser a ...
Aim Our aims were to test the predictions of the vicariance model, searching for natural, non-ran... more Aim Our aims were to test the predictions of the vicariance model, searching for natural, non-random biogeographical units using data on snake distributions, and to assess the conservation of biogeographical patterns and underlying processes in the poorly studied Caatinga region.
Little is known about vital rates of snakes generally because of the difficulty in collecting dat... more Little is known about vital rates of snakes generally because of the difficulty in collecting data. Here we used a robust design mark-recapture model to estimate survival, behavioral effects on capture probability, temporary emigration, abundance and test the hypothesis of population decline in the golden lancehead pitviper, Bothrops insularis, an endemic and critically endangered species from southeastern Brazil. We collected data at irregular intervals over ten occasions from 2002 to 2010. Survival was slightly higher in the wet season than in the dry season. Temporal emigration was high, indicating the importance of accounting for this parameter both in the sampling design and modeling. No behavioral effects were detected on capture probability. We detected an average annual population decrease (l = 0.93, CI = 0.47-1.38) during the study period, but estimates included high uncertainty, and caution in interpretation is needed. We discuss the potential effects of the illegal removal of individuals and the implications of the vital rates obtained for the future persistence and conservation of this endemic, endangered species.
2003. Comparing species richness among assemblages using sample units: why not use extrapolation ... more 2003. Comparing species richness among assemblages using sample units: why not use extrapolation methods to standardize different sample sizes? -Oikos 101: 398-410.
Background/Question/Methods Most anurans undergo a major ontogenetic niche shift, as tadpoles the... more Background/Question/Methods Most anurans undergo a major ontogenetic niche shift, as tadpoles they occupy aquatic habitats and then terrestrial habitats as adults. Thus, considering that habitats occupied by tadpoles are determined by the breeding choices of adults, we hypothesized that: 1) environmental filters have a stronger effect on adults than on tadpoles; 2) adult traits (e.g., presence of adhesive disc, reproductive behavior) are more associated with extrinsic characteristics of breeding habitats (e.g., canopy cover), and tadpole traits (e.g., body size, fin height) are more associated with intrinsic characteristics (e.g., aquatic vegetation); 3) phylogeny is a proxy for trait diversification in communities of both tadpoles and adults. We tested whether phylogenetic and trait diversification were different than expected by chance across breeding habitats along the ontogenetic gradient. We also investigated the relationship between phylogeny, morphological and life-history tr...
Apresentamos as 24 espécies de anfíbios anuros que ocorrem no Parque Estadual das Furnas do Bom J... more Apresentamos as 24 espécies de anfíbios anuros que ocorrem no Parque Estadual das Furnas do Bom Jesus (PEFBJ), Pedregulho, São Paulo, sudeste do Brasil. Barycholos ternetzi, Rhinella rubescens, Scinax canastrensis e Phyllomedusa ayeaye correspondem a novos registros para o estado de São Paulo, sendo a última espécie incluída na lista de espécies ameaçadas de extinção do Ibama e IUCN. Para caracterizar a taxocenose de anuros do PEFBJ, comparamos sua composição de espécies com a de outras 66 localidades em diversos biomas e fitofisionomias do Brasil. As 67 taxocenoses foram ordenadas e agrupadas por meio de uma Análise de Coordenadas Principais (ACOP) e uma Análise de Agrupamento (Cluster Analysis). As análises multivariadas permitiram a identificação de quatro grupos: um de taxocenoses amazônicas; dois de taxocenoses de Mata Atlântica, sendo um composto por floresta ombrófila densa dos estados da Bahia e Espírito Santo e sua transição com a floresta estacional semidecidual (Minas Ger...
Boletin de la Asociación Herpetológica Española, 2000
Resumen: Se presenta una nueva localidad de Ia tortuga Phrynops vanderhaegei en Brasil sudorienta... more Resumen: Se presenta una nueva localidad de Ia tortuga Phrynops vanderhaegei en Brasil sudoriental. Los especimenes se localizaron en un area de savana (cerrado) con pequefios tramos de bosque ripario. Se cementa brevemente el habitat circundante. El hallazgo de esta poblaci6n aislada puede ser importante en Ia conservaci6n de Ia especie ya que indica que otras poblaciones podrian sobrevivir y reproducirse en pequefios fragmentos con vegetaci6n bien conservada. Key words: Brazil, Chelidae, conservation, Phrynops ...
We evaluated the use of oral deformities as reliable proxies for determining Batrachochytrium den... more We evaluated the use of oral deformities as reliable proxies for determining Batrachochytrium dendrobatidis (Bd) infection in tadpoles of six anuran species of the Atlantic Forest in southeastern Brazil. We examined oral discs of 2156 tadpoles of six species of anurans collected in 2016: Aplastodiscus albosignatus, Boana albopunctata, Boana faber, Scinax hayii, Crossodactylus caramaschii, and Physalaemus cuvieri. Three oral deformities were recognized: lack of keratinization only in upper and/or lower jaw sheaths, lack of keratinization only in upper or lower tooth rows, and both deformities together. A subsample composed of all the individuals possessing oral deformities (N = 195) plus randomly selected individuals without oral deformities (N = 184) were tested for Bd via qPCR. Oral deformities were observed in all six species, but only five were infected with Bd. Since we found that dekeratinization of tooth rows was not associated with the presence of Bd in any of the studied spe...
Resumo: As taxocenoses de serpentes neotropicais apresentam alta riqueza de espécies e estruturas... more Resumo: As taxocenoses de serpentes neotropicais apresentam alta riqueza de espécies e estruturas complexas. O Cerrado é o segundo maior bioma do Brasil e foi incluído entre os 25 hotspots globais de biodiversidade. No sudeste do Brasil, as áreas remanescentes de Cerrado têm sofrido intensa destruição, e atualmente restam menos de 2% da vegetação natural de Cerrado no estado de São Paulo. Praticamente nenhum estudo detalhado sobre serpentes do Cerrado foi realizado nesta região. A região de Itirapina apresenta um dos ...
We evaluated the use of oral deformities as reliable proxies for determining Batrachochy-trium de... more We evaluated the use of oral deformities as reliable proxies for determining Batrachochy-trium dendrobatidis (Bd) infection in tadpoles of six anuran species of the Atlantic Forest in southeastern Brazil. We examined oral discs of 2156 tadpoles of six species of anurans collected in 2016: Aplastodiscus albosignatus, Boana albopunctata, Boana faber, Scinax hayii, Crossodactylus caramaschii, and Physalaemus cuvieri. Three oral deformities were recognized: lack of keratinization only in upper and/or lower jaw sheaths, lack of keratinization only in upper or lower tooth rows, and both deformities together. A subsample composed of all the individuals possessing oral deformities (N = 195) plus randomly selected individuals without oral deformities (N = 184) were tested for Bd via qPCR. Oral deformities were observed in all six species, but only five were infected with Bd. Since we found that dekerati-nization of tooth rows was not associated with the presence of Bd in any of the studied species we used a new proxy (jaw sheaths dekeratinization with or without dekeratinization in tooth rows: JSD-proxy) for Bd detection. Our results showed a nonrandom relationship between Bd infection and JSD-proxy in three species of the family Hylidae. However, the use of JSD-proxy for Bd detection in these species resulted in up to 30.8% false positives and up to 29.3% false negatives. The use of the JSD-proxy in species for which no relationship was found reached 100% of false positives. We conclude that the use of oral dekeratini-zation as a generalized proxy for Bd detection in tadpoles should not be used as a single diagnosis technique.
Polygyny is a common mating system in lizards. In polygynous species, males usually display statu... more Polygyny is a common mating system in lizards. In polygynous species, males usually display status badges and use weaponry to prevent reproductive access of competitors to mates. Such secondary sexual traits are frequently linked to signalling costs and the handicap principle is widely used to explain the potential reduction of fitness components. Here, we (1) evaluate the allometric relationship of two known secondary sexual traits with body size: head width (a weapon) and the total coloured lateral area (an ornament), (2) assess the effects of such traits on male and female survival probabilities and (3) evaluate patterns of linear and quadratic selection of both traits for the whiptail lizard Cnemidophorus cf. ocellifer. We detected evidence of sexual dimorphism in both traits, but contrary to our expectations , both sexes presented hyperallometric growth of both weapon size and badge size. We found no support for the handicap principle since no detrimental effects of secondary sexual traits were found on individual survival probability. Furthermore, no evidence of directional selection, neither stabilizing nor disruptive selection was found. The costs of faking signals in male animal contests could maintain the honesty, as previously suggested.
The State of São Paulo is one of the most studied regions of Brazil in regard to amphibian specie... more The State of São Paulo is one of the most studied regions of Brazil in regard to amphibian species richness and distribution. However, we still do not have a list of species for the State. Therefore, we present here a list including 231 species of amphibians (225 anurans and six caecilians), of which 27 are endemic. We present data about previous and current taxonomists and speculate about future prospects in the study and conservation of amphibian biodiversity in São Paulo State.
Most miniaturized froglets of the genus Brachycephalus occur in isolation in slopes of mountain r... more Most miniaturized froglets of the genus Brachycephalus occur in isolation in slopes of mountain ranges at elevations varying from 600 to 1,800 m in the Atlantic Forest of eastern Brazil. For organisms such as Bracycephalus with spatially discontinuous distributions, a fundamental task is to determine whether observed patterns of variation are consistent with geographic differentiation among allopatric populations within a single species or are suggestive of a potential species boundary. We address this problem by focusing on continental and island population samples potentially assignable to Brachycephalus nodoterga (Anura: Brachycephalidae) from the perspective of variation in qualitative and quantitative morphological traits and DNA sequences. Population samples from continental and island populations share color characteristics, qualitative traits, and multivariate patterns of variation and covariation in cranial metric traits. Comparative analysis of DNA sequences showed the magnitude of molecular distances between B. nodoterga and Brachycephalus ephippium to be 1 order of magnitude larger than molecular distances within B. nodoterga and B. ephippium. We interpret the combined morphological and molecular evidence to indicate that continental and island population samples examined here are conspecific. Therefore, by defining species boundaries for B. nodoterga, we also established minimal estimates of its distribution range.
RESUMO A última lista de espécies do Estado de São Paulo foi atualizada, totalizando 236 espécies... more RESUMO A última lista de espécies do Estado de São Paulo foi atualizada, totalizando 236 espécies de anfíbios, das quais 230 são anuros e seis são Gymnophiona. Foram removidos da lista Bokermannohyla gouveai e Sphaenorhynchus surdus por não ocorrerem no Estado de São Paulo. O número de espécies de anuros registrado representa 27% da riqueza de espécies do país e um aumento de 31% em relação ao número de espécies registradas para o Estado em 1998, demonstrando que, a despeito do Estado de São Paulo ser a ...
Aim Our aims were to test the predictions of the vicariance model, searching for natural, non-ran... more Aim Our aims were to test the predictions of the vicariance model, searching for natural, non-random biogeographical units using data on snake distributions, and to assess the conservation of biogeographical patterns and underlying processes in the poorly studied Caatinga region.
Little is known about vital rates of snakes generally because of the difficulty in collecting dat... more Little is known about vital rates of snakes generally because of the difficulty in collecting data. Here we used a robust design mark-recapture model to estimate survival, behavioral effects on capture probability, temporary emigration, abundance and test the hypothesis of population decline in the golden lancehead pitviper, Bothrops insularis, an endemic and critically endangered species from southeastern Brazil. We collected data at irregular intervals over ten occasions from 2002 to 2010. Survival was slightly higher in the wet season than in the dry season. Temporal emigration was high, indicating the importance of accounting for this parameter both in the sampling design and modeling. No behavioral effects were detected on capture probability. We detected an average annual population decrease (l = 0.93, CI = 0.47-1.38) during the study period, but estimates included high uncertainty, and caution in interpretation is needed. We discuss the potential effects of the illegal removal of individuals and the implications of the vital rates obtained for the future persistence and conservation of this endemic, endangered species.
2003. Comparing species richness among assemblages using sample units: why not use extrapolation ... more 2003. Comparing species richness among assemblages using sample units: why not use extrapolation methods to standardize different sample sizes? -Oikos 101: 398-410.
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