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1.
Braz. j. biol ; 81(4): 1144-1165, Oct.-Dec. 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153445

RESUMEN

Abstract Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called "restinga" and "campo nativo" habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.


Resumo Embora atualmente exista um conjunto de estudos sobre aspectos ecológicos de algumas espécies de répteis e de anfíbios que ocorrem nas planícies costeiras arenosas brasileiras (incluindo os chamados habitats de "restinga" e de "campo nativo"), há relativamente poucas informações sobre a composição de espécies geralmente associada a esses ambientes. Durante 31 anos (1988-2019) de estudos herpetológicos realizados em restingas por nossa equipe de pesquisa do Laboratório de Ecologia de Vertebrados (Departamento de Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil) nós estudamos comunidades de répteis e de anfíbios e realizamos diferentes estudos com métodos semelhantes em 70 localidades de dez diferentes Estados ao longo da costa brasileira. Nossas pesquisas resultaram em registros de 87 espécies de répteis (cinco tartarugas, dois crocodilianos, seis anfisbênios, 36 lagartos e 39 serpentes) de 24 famílias, e 77 espécies de anfíbios anuros de nove famílias. Estudamos vários tópicos de história natural sobre anuros e répteis, que resultaram na publicação de alguns estudos ecológicos específicos, especialmente em relação a algumas espécies, abrangendo ecologia populacional e de comunidades, forrageamento e dieta, horário de atividade de espécies, termorregulação, reprodução, uso do microhabitat e parasitismo por ecto e endoparasitas. Nossos resultados ao longo dessas três décadas também contribuíram para a descrição de quatro novas espécies de lagartos (Ameivula nativo, Glaucomastix littoralis, G. abaetensis e G. itabaianensis). Nossos estudos constituem uma importante contribuição para o conhecimento da ecologia de répteis e de anfíbios anuros nesses ecossistemas, bem como para a conservação dos ecossistemas de restinga. A lista de espécies apresentada neste estudo, com base em nossos registros de herpetofauna das planícies costeiras arenosas, fornece para muitas localidades ao longo da costa brasileira o conhecimento necessário sobre a ocorrência de espécies, incluindo a presença de espécies endêmicas e/ ou ameaçadas de extinção, que podem ser úteis para muitas ações de conservação.


Asunto(s)
Animales , Ecosistema , Lagartos , Anuros , Brasil , Arena
2.
Braz J Biol ; 81(4): 1144-1165, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33111929

RESUMEN

Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called "restinga" and "campo nativo" habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.


Asunto(s)
Ecosistema , Lagartos , Animales , Anuros , Brasil , Arena
3.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467521

RESUMEN

Abstract Although currently there is already a set of studies regarding ecological aspects of some particular reptile and amphibian species living in Brazilian sandy coastal plains (including the so-called restinga and campo nativo habitats), there is comparatively few information on the species composition usually associated to these environments. During 31 years (1988-2019) of herpetological studies carried out in sandy coastal plains environments by our research team of the Laboratory of Vertebrate Ecology (Department of Ecology, Universidade do Estado do Rio de Janeiro, in Rio de Janeiro Brazil) we have surveyed reptile and amphibian communities and performed different studies with similar methods in 70 sites from 10 different states along the Brazilian coast. Our surveys resulted in records of 87 species of reptile (five turtles, two crocodylians, six amphisbaenians, 36 lizards and 39 snakes) from 24 families, and 77 species of anuran amphibians from nine families. We have studied multiple natural history topics for anurans and reptiles which resulted in the publication of some specific ecological studies, especially regarding some species, encompassing population and community ecology, foraging and feeding habits, species activity, thermoregulation, reproduction, use of microhabitats, and parasitism by ecto and endoparasites. Our results along these three decades have also contributed for the description of four new lizard species (Ameivula nativo, Glaucomastix littoralis, G. abaetensis and G. itabaianensis). Our studies constitute an important contribution to the knowledge of the ecology of anuran amphibians and reptiles in these ecosystems, as well as to the conservation of sandy coastal plains environment. The checklist presented in this study, based on our records of sandy coastal plains herpetofauna, provides for many localities along the Brazilian coast, the needed knowledge on species occurrence, including the presence of endemic and/or endangered species, which can be of value for many conservation actions.


Resumo Embora atualmente exista um conjunto de estudos sobre aspectos ecológicos de algumas espécies de répteis e de anfíbios que ocorrem nas planícies costeiras arenosas brasileiras (incluindo os chamados habitats de restinga e de campo nativo), há relativamente poucas informações sobre a composição de espécies geralmente associada a esses ambientes. Durante 31 anos (1988-2019) de estudos herpetológicos realizados em restingas por nossa equipe de pesquisa do Laboratório de Ecologia de Vertebrados (Departamento de Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brasil) nós estudamos comunidades de répteis e de anfíbios e realizamos diferentes estudos com métodos semelhantes em 70 localidades de dez diferentes Estados ao longo da costa brasileira. Nossas pesquisas resultaram em registros de 87 espécies de répteis (cinco tartarugas, dois crocodilianos, seis anfisbênios, 36 lagartos e 39 serpentes) de 24 famílias, e 77 espécies de anfíbios anuros de nove famílias. Estudamos vários tópicos de história natural sobre anuros e répteis, que resultaram na publicação de alguns estudos ecológicos específicos, especialmente em relação a algumas espécies, abrangendo ecologia populacional e de comunidades, forrageamento e dieta, horário de atividade de espécies, termorregulação, reprodução, uso do microhabitat e parasitismo por ecto e endoparasitas. Nossos resultados ao longo dessas três décadas também contribuíram para a descrição de quatro novas espécies de lagartos (Ameivula nativo, Glaucomastix littoralis, G. abaetensis e G. itabaianensis). Nossos estudos constituem uma importante contribuição para o conhecimento da ecologia de répteis e de anfíbios anuros nesses ecossistemas, bem como para a conservação dos ecossistemas de restinga. A lista de espécies apresentada neste estudo, com base em nossos registros de herpetofauna das planícies costeiras arenosas, fornece para muitas localidades ao longo da costa brasileira o conhecimento necessário sobre a ocorrência de espécies, incluindo a presença de espécies endêmicas e/ ou ameaçadas de extinção, que podem ser úteis para muitas ações de conservação.

4.
Braz J Biol ; 75(2): 261-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26132005

RESUMEN

In general, anurans tend to be nocturnal, though diurnal activity is characteristic of some groups. Studies show that frog activity may be inferred based on the number of individuals collected at different periods of the day, during large-scale field surveys. We investigated the best period of the day to conduct amphibian sampling in nine Atlantic Rainforest areas in southeastern Brazil, based on intensive field surveys. At each locality we employed similar sampling effort during diurnal, crepuscular and nocturnal searches (totaling 704.5 sampling hours). We pooled data from all localities for each period and estimated the proportion of frogs of each species active at each period based on the total number of individuals and on the number of species found during all surveys for that period. We recorded a total of 817 individual frogs from 69 species. Species richness was highest at night (median = 12 species), intermediate at dusk (median = 8), and lowest during the day (median = 4). The percentage of the total number of individual frogs found (pooled species) was highest during the night (ca. 53%) and lowest during the day (ca. 14%). Analyzing each species separately, the number of individuals recorded was consistently higher at dusk and night for most species. Our study evidences a trend for nocturnal activity for most Atlantic Rainforest frogs, with few species having primarily diurnal habits. Those results may favor future studies and conservation efforts for amphibian species.


Asunto(s)
Anuros/fisiología , Conducta Animal/fisiología , Biodiversidad , Ritmo Circadiano/fisiología , Animales , Anuros/clasificación , Brasil , Bosques , Densidad de Población
5.
Braz. j. biol ; 75(2): 261-267, 05/2015. tab
Artículo en Inglés | LILACS | ID: lil-749694

RESUMEN

In general, anurans tend to be nocturnal, though diurnal activity is characteristic of some groups. Studies show that frog activity may be inferred based on the number of individuals collected at different periods of the day, during large-scale field surveys. We investigated the best period of the day to conduct amphibian sampling in nine Atlantic Rainforest areas in southeastern Brazil, based on intensive field surveys. At each locality we employed similar sampling effort during diurnal, crepuscular and nocturnal searches (totaling 704.5 sampling hours). We pooled data from all localities for each period and estimated the proportion of frogs of each species active at each period based on the total number of individuals and on the number of species found during all surveys for that period. We recorded a total of 817 individual frogs from 69 species. Species richness was highest at night (median = 12 species), intermediate at dusk (median = 8), and lowest during the day (median = 4). The percentage of the total number of individual frogs found (pooled species) was highest during the night (ca. 53%) and lowest during the day (ca. 14%). Analyzing each species separately, the number of individuals recorded was consistently higher at dusk and night for most species. Our study evidences a trend for nocturnal activity for most Atlantic Rainforest frogs, with few species having primarily diurnal habits. Those results may favor future studies and conservation efforts for amphibian species.


Em geral, anuros tendem a ser noturnos, apesar de a atividade diurna ser característica de alguns grupos. Estudos mostram que a atividade de anuros pode ser inferida com base no número de indivíduos coletados em diferentes períodos do dia durante pesquisas de campo de larga escala. Nós avaliamos qual o melhor período do dia para conduzir amostragens de anfíbios em nove áreas da Mata Atlântica no sudeste do Brasil, com base em amostragens de campo intensivas. Em cada localidade nós empregamos esforço de amostragem similar durante amostragens diurnas, crepusculares e noturnas (totalizando 704,5 horas de amostragem). Nós agrupamos dados de todas as localidades para cada período e estimamos a proporção de anuros de cada espécie ativa em cada período com base no número total de indivíduos e no número de espécies encontradas durante todas as buscas naquele período. Nós registramos um total de 817 indivíduos pertencentes a 69 espécies. A riqueza de espécies foi maior à noite (mediana = 12 espécies), intermediária ao crepúsculo (mediana = 8) e menor durante o dia (mediana = 4). A porcentagem do número total de indivíduos encontrados (todas as espécies agrupadas) foi maior durante a noite (ca. 53%) e menor durante o período diurno (ca. 14%). Analisando cada espécie separadamente, o número de indivíduos registrados foi consistentemente maior ao crepúsculo e à noite para a maioria das espécies. Nosso estudo evidencia uma tendência para atividade noturna para a maioria dos anuros da Mata Atlântica, com poucas espécies tendo hábitos primariamente diurnos. Esses resultados podem favorecer futuros estudos e esforços de conservação para as espécies de anfíbios.


Asunto(s)
Animales , Anuros/fisiología , Biodiversidad , Conducta Animal/fisiología , Ritmo Circadiano/fisiología , Anuros/clasificación , Brasil , Bosques , Densidad de Población
6.
Braz J Biol ; 74(2): 349-54, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25166319

RESUMEN

Habitat fragmentation is well known to adversely affect species living in the remaining, relatively isolated, habitat patches, especially for those having small range size and low density. This negative effect has been critical in coastal resting habitats. We analysed the lizard composition and richness of restinga habitats in 16 restinga habitats encompassing three Brazilian states (Rio de Janeiro, Espírito Santo and Bahia) and more than 1500km of the Brazilian coast in order to evaluate if the loss of lizard species following habitat reduction occur in a nested pattern or at random, using the "Nestedness Temperature Calculator" to analyse the distribution pattern of lizard species among the restingas studied. We also estimated the potential capacity that each restinga has to maintain lizard species. Eleven lizard species were recorded in the restingas, although not all species occurred in all areas. The restinga with the richest lizard fauna was Guriri (eight species) whereas the restinga with the lowest richness was Praia do Sul (located at Ilha Grande, a large coastal island). Among the restingas analysed, Jurubatiba, Guriri, Maricá and Praia das Neves, were the most hospitable for lizards. The matrix community temperature of the lizard assemblages was 20.49° (= P <0.00001; 5000 randomisations; randomisation temperature = 51.45° ± 7.18° SD), indicating that lizard assemblages in the coastal restingas exhibited a considerable nested structure. The degree in which an area is hospitable for different assemblages could be used to suggest those with greater value of conservation. We concluded that lizard assemblages in coastal restingas occur at a considerable level of ordination in restinga habitats and that some restinga areas such as Jurubatiba, Guriri, Maricá and Praia das Neves are quite important to preserve lizard diversity of restinga environments.


Asunto(s)
Ecosistema , Lagartos/clasificación , Animales , Biodiversidad , Brasil , Densidad de Población , Temperatura
7.
Braz J Biol ; 74(1): 199-204, 2014 02.
Artículo en Inglés | MEDLINE | ID: mdl-25055102

RESUMEN

Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna.


Asunto(s)
Conducta Alimentaria/fisiología , Lagartos/clasificación , Infecciones por Nematodos/parasitología , Animales , Brasil , Femenino , Contenido Digestivo , Iguanas , Lagartos/parasitología , Lagartos/fisiología , Masculino , Infecciones por Nematodos/veterinaria
8.
Braz. j. biol ; 74(2): 349-354, 5/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-719236

RESUMEN

Habitat fragmentation is well known to adversely affect species living in the remaining, relatively isolated, habitat patches, especially for those having small range size and low density. This negative effect has been critical in coastal resting habitats. We analysed the lizard composition and richness of restinga habitats in 16 restinga habitats encompassing three Brazilian states (Rio de Janeiro, Espírito Santo and Bahia) and more than 1500km of the Brazilian coast in order to evaluate if the loss of lizard species following habitat reduction occur in a nested pattern or at random, using the “Nestedness Temperature Calculator” to analyse the distribution pattern of lizard species among the restingas studied. We also estimated the potential capacity that each restinga has to maintain lizard species. Eleven lizard species were recorded in the restingas, although not all species occurred in all areas. The restinga with the richest lizard fauna was Guriri (eight species) whereas the restinga with the lowest richness was Praia do Sul (located at Ilha Grande, a large coastal island). Among the restingas analysed, Jurubatiba, Guriri, Maricá and Praia das Neves, were the most hospitable for lizards. The matrix community temperature of the lizard assemblages was 20.49° (= P <0.00001; 5000 randomisations; randomisation temperature = 51.45° ± 7.18° SD), indicating that lizard assemblages in the coastal restingas exhibited a considerable nested structure. The degree in which an area is hospitable for different assemblages could be used to suggest those with greater value of conservation. We concluded that lizard assemblages in coastal restingas occur at a considerable level of ordination in restinga habitats and that some restinga areas such as Jurubatiba, Guriri, Maricá and Praia das Neves are quite important to preserve lizard diversity of restinga environments.


A fragmentação dos habitats constitui um importante fator bem conhecido por afetar negativamente as espécies que vivem em porções relativamente isoladas de habitats ou de de manchas de hábitat e, especificamente para aquelas que possuem menores extensões de área e menores densidades populacionais. Este efeito negativo tem sido crítico nos habitats de restingas. Nós analisamos a composição e a riqueza de lagartos de habitats de restinga em 16 áreas de restingas, abrangendo três estados brasileiros (Rio de Janeiro, Espírito Santo e Bahia), ao longo de mais de 1500 km da costa brasileira, visando avaliar se a perda de espécies de lagartos acompanharia a redução de habitat seguindo um padrão aninhado ou de forma aleatório, com uso do programa “Nestedness Temperature Calculator” para analisar o padrão de distribuição de espécies de lagartos entre as restingas estudadas. Estimamos também a capacidade potencial de cada área de restinga em manter as espécies de lagartos. Onze espécies de lagartos foram registradas nas restingas, embora nem todas as espécies tenham ocorrido em todas as áreas amostradas. A restinga com a maior riqueza de lagartos foi Guriri (oito espécies), enquanto a restinga com a menor riqueza foi a da Praia do Sul (localizada na Ilha Grande, uma grande ilha costeira no sudeste do Brasil). Entre as restingas analisadas, Jurubatiba, Guriri, Maricá e Praia das Neves, foram as mais favoráveis para os lagartos. A temperatura da matriz da comunidade de lagartos foi de 20.49°C (= P <0,00001; 5000 aleatorizações; temperatura randomizada = 51,45°C + 7.18°C SD), o que indicou que as assembleias de lagartos nas restingas costeiras teve uma estrutura considerável aninhada. O grau segundo o qual uma área é mais favorável para diferentes assembléias pode ser utilizado como parâmetro para agregar maior valor de conservação desta área. Concluímos que as assembléias de lagartos nas restingas costeiras ocorreram em um considerável nível de ordenação e que algumas áreas de restinga como Jurubatiba, Guriri, Maricá e Praia das Neves são importantes e estratégicas para preservar a diversidade de lagartos de ambientes de restinga.


Asunto(s)
Animales , Ecosistema , Lagartos/clasificación , Biodiversidad , Brasil , Densidad de Población , Temperatura
9.
Braz. j. biol ; 74(1): 199-204, 2/2014. tab
Artículo en Inglés | LILACS | ID: lil-715595

RESUMEN

Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna.


Nosso estudo teve como objetivo adicionar informações sobre a dieta e endoparasitas de Enyalius brasiliensis em um remanescente de Mata Atlântica do estado do Rio de Janeiro, sudeste do Brasil. Em relação à dieta, E. brasiliensis consumiu artrópodes, sendo que lagartas e besouros foram as presas mais importantes. Em relação ao parasitismo por helmintos, a prevalência foi baixa (9,5%), com 238 nematóides do gênero Physaloptera encontrados no estômago de um espécime, e um nematóide do gênero Rhabdias infectando o pulmão de outro. Nossos resultados corroboraram as observações de estudos anteriores que indicaram que lagartos do gênero Enyalius tendem a se alimentar principalmente de artrópodos de grande porte e abrigar uma fauna depauperada de endoparasitas.


Asunto(s)
Animales , Femenino , Masculino , Conducta Alimentaria/fisiología , Lagartos/clasificación , Infecciones por Nematodos/parasitología , Brasil , Contenido Digestivo , Iguanas , Lagartos/parasitología , Lagartos/fisiología , Infecciones por Nematodos/veterinaria
10.
Trop Plant Biol ; 5(3): 233-243, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22905278

RESUMEN

Mutator-like transposase is the most represented transposon transcript in the sugarcane transcriptome. Phylogenetic reconstructions derived from sequenced transcripts provided evidence that at least four distinct classes exist (I-IV) and that diversification among these classes occurred early in Angiosperms, prior to the divergence of Monocots/Eudicots. The four previously described classes served as probes to select and further sequence six BAC clones from a genomic library of cultivar R570. A total of 579,352 sugarcane base pairs were produced from these "Mutator system" BAC containing regions for further characterization. The analyzed genomic regions confirmed that the predicted structure and organization of the Mutator system in sugarcane is composed of two true transposon lineages, each containing a specific terminal inverted repeat and two transposase lineages considered to be domesticated. Each Mutator transposase class displayed a particular molecular structure supporting lineage specific evolution. MUSTANG, previously described domesticated genes, are located in syntenic regions across Sacharineae and, as expected for a host functional gene, posses the same gene structure as in other Poaceae. Two sequenced BACs correspond to hom(eo)logous locus with specific retrotransposon insertions that discriminate sugarcane haplotypes. The comparative studies presented, add information to the Mutator systems previously identified in the maize and rice genomes by describing lineage specific molecular structure and genomic distribution pattern in the sugarcane genome. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12042-012-9104-y) contains supplementary material, which is available to authorized users.

12.
Braz J Biol ; 70(3 Suppl): 871-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21085792

RESUMEN

We carried out a study on the anurofaunal community from an Atlantic Forest fragment (Monte Verde mountains) and the surrounding area in Cambuci municipality, Rio de Janeiro State, Brazil, which constitutes one of the largest fragments remaining in the largely deforested landscape of the northern portion of the State. We combined three sampling methods: plot sampling, transects and pit-fall traps. We recorded twenty species of amphibians, of which only eleven were found within the forest fragment (and five of these also occurred in the surrounding matrix). Two of the species recorded in the present study (Crossodactylus sp. and Ischnocnema cf. parva) may represent undescribed taxa. Our records expand the distribution range of one species (Scinax trapicheiroi) to the north, and fill a geographic distribution gap for another one (Ischnocnema oea). The estimated overall density of frogs living in the leaf litter of the fragment (based on results of plot sampling) was 3.1 individuals/100 m², with Haddadus binotatus being the most abundant species (2.4 individuals/100 m²). Comparisons of our data with those of other studies suggest that anuran communities in forest fragments ca. 1,000 ha or smaller may be severely limited in their richness, and often include a large proportion of species tolerant to open areas, such as many hylids. Our results show the importance of increasing knowledge about the anurofaunal community of the northern portion of the State of Rio de Janeiro and preserve the forest remnants that still exist in the region.


Asunto(s)
Anuros/clasificación , Árboles , Animales , Brasil , Conservación de los Recursos Naturales , Densidad de Población , Dinámica Poblacional
13.
Braz. j. biol ; 70(3)Aug. 2010.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468046

RESUMEN

We carried out a study on the anurofaunal community from an Atlantic Forest fragment (Monte Verde mountains) and the surrounding area in Cambuci municipality, Rio de Janeiro State, Brazil, which constitutes one of the largest fragments remaining in the largely deforested landscape of the northern portion of the State. We combined three sampling methods: plot sampling, transects and pit-fall traps. We recorded twenty species of amphibians, of which only eleven were found within the forest fragment (and five of these also occurred in the surrounding matrix). Two of the species recorded in the present study (Crossodactylus sp. and Ischnocnema cf. parva) may represent undescribed taxa. Our records expand the distribution range of one species (Scinax trapicheiroi) to the north, and fill a geographic distribution gap for another one (Ischnocnema oea). The estimated overall density of frogs living in the leaf litter of the fragment (based on results of plot sampling) was 3.1 individuals/100 m², with Haddadus binotatus being the most abundant species (2.4 individuals/100 m²). Comparisons of our data with those of other studies suggest that anuran communities in forest fragments ca. 1,000 ha or smaller may be severely limited in their richness, and often include a large proportion of species tolerant to open areas, such as many hylids. Our results show the importance of increasing knowledge about the anurofaunal community of the northern portion of the State of Rio de Janeiro and preserve the forest remnants that still exist in the region.


Conduzimos um estudo de curta duração sobre a comunidade de anurofauna de um fragmento de Mata Atlântica (Serra do Monte Verde) localizado no município de Cambuci, Estado do Rio de Janeiro, Brasil, o qual constitui um dos maiores fragmentos remanescentes ainda existentes na paisagem amplamente desflorestada da porção norte do Estado. Utilizamos três métodos de amostragem combinados: parcelas, transectos e armadilhas de queda. Registramos vinte espécies de anfíbios, das quais apenas onze foram encontradas dentro do fragmento florestal (e dessas, cinco também ocorreram no seu entorno). Duas das espécies registradas no presente trabalho (Crossodactylus sp. e Ischnocnema cf. parva) podem representar táxons ainda não descritos. Nossos registros expandem a distribuição geográfica de uma espécie (Scinax trapicheiroi) para o norte e preenchem uma lacuna na distribuição de outra (Ischnocnema oea). A densidade total estimada de anfíbios anuros vivendo na camada de folhiço do fragmento (baseada nos resultados do método de plots) foi de 3,1 indivíduos/100 m², sendo Haddadus binotatus a espécie mais abundante (2,4 indivíduos/100 m²). Comparações de nossos dados com os de outros estudos sugerem que comunidades de anuros em fragmentos florestais com cerca de 1.000 ha ou menos podem ser severamente limitados em sua riqueza e frequentemente incluem uma grande proporção de espécies tolerantes a ambientes abertos, como é o caso de vários hilídeos. Nossos resultados demonstram a importância de ampliar o conhecimento sobre a anurofauna da região norte do Estado do Rio de Janeiro e de conservar os poucos remanescentes florestais ainda existentes na região.

14.
Braz J Biol ; 69(2): 429-35, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19675949

RESUMEN

The reproductive cycles of lizards, including Tropidurus species, have been widely studied. However, few studies describe in detail the ultrastructure and the epithelial changes in the epididymis. Using histology and trasmission electron microscopy, we show the seasonal changes in the testis and epididymis of the lizard Tropidurus itambere, during its annual reproductive cycle. The reproductive cycle of T. itambere was analysed from June 1988 to June 1989 and from June 2001 to June 2002. While the frequency of reproductive males in the population varied throughout the year, there were reproductive males in most months except for February through April. During this nonreproductive period, there is a reduction in the mean seminiferous tubule volume and few sperm were found in both the testis and the epididymis.


Asunto(s)
Epidídimo/anatomía & histología , Lagartos/anatomía & histología , Estaciones del Año , Espermatogénesis/fisiología , Testículo/anatomía & histología , Animales , Epidídimo/ultraestructura , Lagartos/fisiología , Masculino , Microscopía Electrónica de Transmisión , Reproducción/fisiología , Testículo/ultraestructura
15.
Braz. j. biol ; 69(2): 429-435, May 2009. ilus
Artículo en Inglés | LILACS | ID: lil-519189

RESUMEN

The reproductive cycles of lizards, including Tropidurus species, have been widely studied. However, few studies describe in detail the ultrastructure and the epithelial changes in the epididymis. Using histology and trasmission electron microscopy, we show the seasonal changes in the testis and epididymis of the lizard Tropidurus itambere, during its annual reproductive cycle. The reproductive cycle of T. itambere was analysed from June 1988 to June 1989 and from June 2001 to June 2002. While the frequency of reproductive males in the population varied throughout the year, there were reproductive males in most months except for February through April. During this nonreproductive period, there is a reduction in the mean seminiferous tubule volume and few sperm were found in both the testis and the epididymis.


O ciclo reprodutivo de alguns lagartos já foi extensamente estudado, incluindo algumas espécies do gênero Tropidurus. Entretanto, poucos estudos mostram os aspectos morfológicos do testículo e epidídimo, durante o ciclo reprodutivo anual, e não existe nenhuma descrição ultraestrutural das variações epiteliais no epidídimo. O presente estudo foi feito para mostrar, através da histologia e microscopia eletrônica de transmissão, detalhes das mudanças sazonais no testículo e epidídimo durante o ciclo reprodutivo anual. Acompanhamos o ciclo de Tropidurus itambere, na floresta atlântica brasileira, durante o período de junho de 2001 a junho de 2002. Os machos variam em sua atividade reprodutiva, mas foram considerados potencialmente reprodutivos na maioria dos meses, à exceção dos meses de fevereiro a abril. Durante este período, ocorreu uma redução no volume médio dos túbulos seminíferos e uma menor quantidade de espermatozóides no testículo e no epidídimo.


Asunto(s)
Animales , Masculino , Epidídimo/anatomía & histología , Lagartos/anatomía & histología , Estaciones del Año , Espermatogénesis/fisiología , Testículo/anatomía & histología , Epidídimo/ultraestructura , Lagartos/fisiología , Microscopía Electrónica de Transmisión , Reproducción/fisiología , Testículo/ultraestructura
16.
Dis Aquat Organ ; 81(2): 93-7, 2008 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-18924373

RESUMEN

Chytridiomycosis, caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), is an emerging infectious disease responsible for amphibian declines on several continents. In laboratory conditions, optimal temperatures for Bd growth and survivorship are between 17 and 25 degrees C. We investigated the effect of different storage temperatures, both in field and laboratory conditions, on detection of Bd from swabs stored for 7 d. We sampled 52 wild Litoria wilcoxii males for Bd by simultaneously running 2 cotton swabs along the skin of the frog. One group of swabs was stored in a freezer within 2 h of sampling and the other was kept in a car in an exposed environment for 7 d before being stored in the freezer. In the laboratory experiment, swabs were inoculated with zoospores of Bd and underwent one of 4 treatments: immediate DNA extraction, or storage at 27, 38 or 45 degrees C for 7 d prior to DNA extraction. Swabs from all treatments were analyzed by quantitative (real-time) PCR test. Though prevalence of Bd did not differ significantly between swabs that were frozen and those that remained in a car for 7 d (19.2 vs. 17.3%, respectively), the number of Bd zoospores detected on car swabs taken from infected frogs was, on average, 67% less than that detected on the corresponding frozen swab. In the laboratory experiment, the number of zoospore equivalents varied significantly with treatment (F(3,35) = 4.769, p = 0.007), indicating that there was reduced recovery of Bd DNA from swabs stored at higher temperatures compared with those stored at lower temperatures or processed immediately. We conclude that failure to store swabs in cool conditions can result in a significant reduction in the amount of Bd DNA detected using the PCR assay. Our results have important implications for researchers conducting field sampling of amphibians for Bd.


Asunto(s)
Anuros/microbiología , Quitridiomicetos/fisiología , ADN de Hongos/química , Calor , Reacción en Cadena de la Polimerasa , Manejo de Especímenes , Animales , Masculino
17.
Parasite ; 15(2): 131-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18642505

RESUMEN

We studied the parasitism by the chigger mite Eutrombicula alfreddugesi on four sympatric lizard species of the genus Tropidurus in Morro do Chapéu, Bahia state, Brazil: T. hispidus, T. cocorobensis, T. semitaeniatus and T. erythrocephalus. For each species, we investigated the patterns of infestation and analyzed to which extent they varied among the hosts. We calculated the spatial niche breadth of the chigger mite on the body of each host species and the distribution of mites along the hosts' bodies for each Tropidurus species. All four species of Tropidurus at Morro do Chapéu were parasited by the chigger mite, with high (97-100%) prevalences. Host body size significantly explained the intensity of mite infestation for all species, except T. erythrocephalus. The body regions with highest intensity of infestation in the four lizard species were the mite pockets. The spacial niche width of the chigger varied consistently among the four lizards species studied being highest for T. erytrocephalus and lowest for T. cocorobensis. We conclude that the distribution and intensity with which lizards of the genus Tropidurus are infested by Eutrombicula alfreddugesi larvae results from the interaction between aspects of host morphology (such as body size and the occurrence and distribution of mite pockets) and ecology (especially microhabitat use).


Asunto(s)
Interacciones Huésped-Parásitos , Lagartos/parasitología , Trombiculiasis/veterinaria , Trombiculidae/parasitología , Animales , Brasil/epidemiología , Lagartos/anatomía & histología , Prevalencia , Especificidad de la Especie , Trombiculiasis/epidemiología , Trombiculiasis/parasitología
18.
J Exp Bot ; 59(10): 2875-90, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18552354

RESUMEN

In tomato, numerous wild-related species have been demonstrated to be untapped sources of valuable genetic variability, including pathogen-resistance genes, nutritional, and industrial quality traits. From a collection of S. pennellii introgressed lines, 889 fruit metabolic loci (QML) and 326 yield-associated loci (YAL), distributed across the tomato genome, had been identified previously. By using a combination of molecular marker sequence analysis, PCR amplification and sequencing, analysis of allelic variation, and evaluation of co-response between gene expression and metabolite composition traits, the present report, provides a comprehensive list of candidate genes co-localizing with a subset of 106 QML and 20 YAL associated either with important agronomic or nutritional characteristics. This combined strategy allowed the identification and analysis of 127 candidate genes located in 16 regions of the tomato genome. Eighty-five genes were cloned and partially sequenced, totalling 45,816 and 45,787 bases from S. lycopersicum and S. pennellii, respectively. Allelic variation at the amino acid level was confirmed for 37 of these candidates. Furthermore, out of the 127 gene-metabolite co-locations, some 56 were recovered following correlation of parallel transcript and metabolite profiling. Results obtained here represent the initial steps in the integration of genetic, genomic, and expressional patterns of genes co-localizing with chemical compositional traits of the tomato fruit.


Asunto(s)
Proteínas de Plantas/genética , Sitios de Carácter Cuantitativo , Solanum lycopersicum/genética , Clonación Molecular , Frutas/química , Frutas/genética , Frutas/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Solanum lycopersicum/química , Solanum lycopersicum/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo
19.
Braz J Biol ; 68(1): 101-7, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18470383

RESUMEN

We studied the species richness and composition of frogs in 10 restinga habitats (sand dune environments dominated by herbaceous and shrubby vegetation) along approximately 1500 km of coastal areas of three Brazilian States: Rio de Janeiro (Grumari, Maricá, Massambaba, Jurubatiba and Grussaí), Espírito Santo (Praia das Neves and Setiba) and Bahia (Prado and Trancoso). We estimated beta-diversity and similarity among areas and related these parameters to geographic distance between areas. All areas were surveyed with a similar sampling procedure. We found 28 frog species belonging to the families Hylidae, Microhylidae, Leptodactylidae and Bufonidae. Frogs in restingas were in general nocturnal with no strictly diurnal species. The richest restinga was Praia das Neves (13 species), followed by Grussaí and Trancoso (eight species in each). The commonest species in the restingas was Scinax alter (found in eight restingas), followed by Aparasphenodon brunoi (seven areas). Our data shows that richness and composition of frog communities vary consistently along the eastern Brazilian coast and, in part, the rate of species turnover is affected by the distance among areas. Geographic distance explained approximately 12% of species turnover in restingas and about 9.5% of similarity among frog assemblages. Although geographic distance somewhat affects frog assemblages, other factors (e.g. historical factors, disturbances) seem to be also involved in explaining present frog assemblage composition in each area and species turnover among areas. The frog fauna along restinga habitats was significantly nested (matrix community temperature = 26.13 degrees; p = 0.007). Our data also showed that the most hospitable restinga was Praia das Neves and indicated that this area should be protected as a conservation unit. Frog assemblage of each area seems to partially represent a nested subset of the original assemblage, although we should not ignore the importance of historical factors. This nestedness pattern, in part, probably results from the intensive fragmentation of restinga habitats. Possibly, many frog species may have been lost in some studied areas as a result of the extensive habitat degradation to which restinga habitats are presently exposed.


Asunto(s)
Anuros/clasificación , Biodiversidad , Animales , Brasil , Densidad de Población
20.
Int J Plant Genomics ; 2008: 458732, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18273390

RESUMEN

Sugarcane is a highly productive crop used for centuries as the main source of sugar and recently to produce ethanol, a renewable bio-fuel energy source. There is increased interest in this crop due to the impending need to decrease fossil fuel usage. Sugarcane has a highly polyploid genome. Expressed sequence tag (EST) sequencing has significantly contributed to gene discovery and expression studies used to associate function with sugarcane genes. A significant amount of data exists on regulatory events controlling responses to herbivory, drought, and phosphate deficiency, which cause important constraints on yield and on endophytic bacteria, which are highly beneficial. The means to reduce drought, phosphate deficiency, and herbivory by the sugarcane borer have a negative impact on the environment. Improved tolerance for these constraints is being sought. Sugarcane's ability to accumulate sucrose up to 16% of its culm dry weight is a challenge for genetic manipulation. Genome-based technology such as cDNA microarray data indicates genes associated with sugar content that may be used to develop new varieties improved for sucrose content or for traits that restrict the expansion of the cultivated land. The genes can also be used as molecular markers of agronomic traits in traditional breeding programs.

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