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1.
Artigo em Inglês | VETINDEX | ID: vti-690310

RESUMO

In this study we analyzed the diet of the gymnophthalmid lizard Ecpleopus gaudichaudii Duméril & Bibron, 1839, a typical inhabitant of the forest-floor leaf litter, in an Atlantic Forest area in the state of Rio de Janeiro, southeastern Brazil. The 26 individuals sampled during the study had a mean snout-vent length (SVL) of 36.2 ± 4.2 mm and a mean jaw width (JW) of 4.1 ± 0.5 mm. We did not find differences in SVL between males and females, though the sexes differed in JW when the effect of body size was factored out, with females presenting higher values. The diet of the lizards was composed exclusively of arthropods, especially isopods and orthopterans. The similarity in trophic niches among seasons (volumetric and numerical proportions of prey categories consumed) were 0.096 and to 0.43, respectively. There were also no detectable seasonal differences in mean number and mean volume of prey ingested, as well as no significant influence of lizard SVL on prey number and of lizard JW on mean prey volume, which may reflect the tendency of E. gaudichaudii to feed on few, relatively large prey.

2.
Artigo em Inglês | VETINDEX | ID: vti-690292

RESUMO

The anurofauna inhabiting higher montane Atlantic forest areas in southeastern Brazil, which often attain heights of more than 2000 m, is still insufficiently known. In this study, we present data on anuran species composition and abundances in two high-altitude (i.e. > 1000 m) sites within the Parque Estadual dos Três Picos (PETP), in the state of Rio de Janeiro. Field surveys were done at altitudes between 1100 and 1900 m above sea level. We recorded 35 species during our study, adding 22 records to the set of anuran species previously known to occur within the PETP. The stability of the species accumulation curve, as well as the richness estimations, showed that the sampling methodology employed and the total sampling effort were appropriate to inventory the anuran assemblages of both sites. Direct-developing frogs such as Ischnocnema parva (Girard, 1853) (at the 1100-1400 m altitude site), and Brachycephalus garbeanus Miranda-Ribeiro, 1920 (at the 1600-1900 m altitude site) were the most locally abundant species. None of the species recorded during the study is listed as threatened, though nine of them are currently considered endemic to the state of Rio de Janeiro. Furthermore, eight of the species recorded are likely restricted to high-altitude habitats. The relatively high diversity of anurans (some of them endemic to the state), the presence of species restricted to high-altitude habitats, and the occurrence of rare and presently undescribed species attest to the biological relevance of the studied areas within the PETP.

3.
Artigo em Inglês | VETINDEX | ID: vti-441302

RESUMO

In this study we analyzed the diet of the gymnophthalmid lizard Ecpleopus gaudichaudii Duméril & Bibron, 1839, a typical inhabitant of the forest-floor leaf litter, in an Atlantic Forest area in the state of Rio de Janeiro, southeastern Brazil. The 26 individuals sampled during the study had a mean snout-vent length (SVL) of 36.2 ± 4.2 mm and a mean jaw width (JW) of 4.1 ± 0.5 mm. We did not find differences in SVL between males and females, though the sexes differed in JW when the effect of body size was factored out, with females presenting higher values. The diet of the lizards was composed exclusively of arthropods, especially isopods and orthopterans. The similarity in trophic niches among seasons (volumetric and numerical proportions of prey categories consumed) were 0.096 and to 0.43, respectively. There were also no detectable seasonal differences in mean number and mean volume of prey ingested, as well as no significant influence of lizard SVL on prey number and of lizard JW on mean prey volume, which may reflect the tendency of E. gaudichaudii to feed on few, relatively large prey.

4.
Artigo em Inglês | VETINDEX | ID: vti-441284

RESUMO

The anurofauna inhabiting higher montane Atlantic forest areas in southeastern Brazil, which often attain heights of more than 2000 m, is still insufficiently known. In this study, we present data on anuran species composition and abundances in two high-altitude (i.e. > 1000 m) sites within the Parque Estadual dos Três Picos (PETP), in the state of Rio de Janeiro. Field surveys were done at altitudes between 1100 and 1900 m above sea level. We recorded 35 species during our study, adding 22 records to the set of anuran species previously known to occur within the PETP. The stability of the species accumulation curve, as well as the richness estimations, showed that the sampling methodology employed and the total sampling effort were appropriate to inventory the anuran assemblages of both sites. Direct-developing frogs such as Ischnocnema parva (Girard, 1853) (at the 1100-1400 m altitude site), and Brachycephalus garbeanus Miranda-Ribeiro, 1920 (at the 1600-1900 m altitude site) were the most locally abundant species. None of the species recorded during the study is listed as threatened, though nine of them are currently considered endemic to the state of Rio de Janeiro. Furthermore, eight of the species recorded are likely restricted to high-altitude habitats. The relatively high diversity of anurans (some of them endemic to the state), the presence of species restricted to high-altitude habitats, and the occurrence of rare and presently undescribed species attest to the biological relevance of the studied areas within the PETP.

5.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1503997

RESUMO

The anurofauna inhabiting higher montane Atlantic forest areas in southeastern Brazil, which often attain heights of more than 2000 m, is still insufficiently known. In this study, we present data on anuran species composition and abundances in two high-altitude (i.e. > 1000 m) sites within the Parque Estadual dos Três Picos (PETP), in the state of Rio de Janeiro. Field surveys were done at altitudes between 1100 and 1900 m above sea level. We recorded 35 species during our study, adding 22 records to the set of anuran species previously known to occur within the PETP. The stability of the species accumulation curve, as well as the richness estimations, showed that the sampling methodology employed and the total sampling effort were appropriate to inventory the anuran assemblages of both sites. Direct-developing frogs such as Ischnocnema parva (Girard, 1853) (at the 1100-1400 m altitude site), and Brachycephalus garbeanus Miranda-Ribeiro, 1920 (at the 1600-1900 m altitude site) were the most locally abundant species. None of the species recorded during the study is listed as threatened, though nine of them are currently considered endemic to the state of Rio de Janeiro. Furthermore, eight of the species recorded are likely restricted to high-altitude habitats. The relatively high diversity of anurans (some of them endemic to the state), the presence of species restricted to high-altitude habitats, and the occurrence of rare and presently undescribed species attest to the biological relevance of the studied areas within the PETP.

6.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1504016

RESUMO

In this study we analyzed the diet of the gymnophthalmid lizard Ecpleopus gaudichaudii Duméril & Bibron, 1839, a typical inhabitant of the forest-floor leaf litter, in an Atlantic Forest area in the state of Rio de Janeiro, southeastern Brazil. The 26 individuals sampled during the study had a mean snout-vent length (SVL) of 36.2 ± 4.2 mm and a mean jaw width (JW) of 4.1 ± 0.5 mm. We did not find differences in SVL between males and females, though the sexes differed in JW when the effect of body size was factored out, with females presenting higher values. The diet of the lizards was composed exclusively of arthropods, especially isopods and orthopterans. The similarity in trophic niches among seasons (volumetric and numerical proportions of prey categories consumed) were 0.096 and to 0.43, respectively. There were also no detectable seasonal differences in mean number and mean volume of prey ingested, as well as no significant influence of lizard SVL on prey number and of lizard JW on mean prey volume, which may reflect the tendency of E. gaudichaudii to feed on few, relatively large prey.

7.
Artigo em Inglês | VETINDEX | ID: vti-690127

RESUMO

Ischnocnema (Brachycephalidae) includes many species that are important members of the leaf litter frog communities in the Atlantic Rainforest of Brazil. Ischnocnema parva (Girard, 1853) is endemic to the Atlantic Rainforest biome and is restricted to the forests of southeastern Brazil. Currently, the available information about the ecology of I. parva is scarce. We studied the diet, the habitat use, reproduction and density of I. parva in an area of Atlantic Rainforest at the Concórdia mountain range, Rio de Janeiro. Individuals of I. parva were captured in April 2005 using different sampling methods: time constrained search (transects), plots of 5 x 5 m (25 m²) on the litter, and pitfall traps with drift fences. We found 240 frogs; 35 females and 205 males. Females (mean SVL = 19.1 mm) were significantly larger (F1,238 = 143.016, R² = 0.375, p 0.001) than males (13.2 mm). The species preyed mainly on arthropods, with ants and isopods being the most important items, both showing high values of importance index (Ix = 50.0 and 26.7, respectively). Ischnocnema parva is a terrestrial species whose preferential microhabitat at the Serra da Concórdia was the litter of the forest floor (78.7%). The activity was predominantly crepuscular-nocturnal and the estimated density of I. parva was 24.9 ind/100 m². For the eight ovigerous females captured, the mean number of mature oocytes per female was 25 (range: 22-30) and the oocyte mean diameter was 1.11 mm (N = 40 oocytes). Oocyte number increased with female body size (R² = 0.504, F1,6 = 6.107, p 0.05, N = 8), indicating that as females increase in size they produce larger clutches. Some ecological aspects such as diet and microhabitat use were similar to that observed for an insular population of I. parva, whereas reproductive traits differed. Thus, long term studies are necessary to understand the extent to which these differences are explained by environmental factors.

8.
Artigo em Inglês | VETINDEX | ID: vti-441119

RESUMO

Ischnocnema (Brachycephalidae) includes many species that are important members of the leaf litter frog communities in the Atlantic Rainforest of Brazil. Ischnocnema parva (Girard, 1853) is endemic to the Atlantic Rainforest biome and is restricted to the forests of southeastern Brazil. Currently, the available information about the ecology of I. parva is scarce. We studied the diet, the habitat use, reproduction and density of I. parva in an area of Atlantic Rainforest at the Concórdia mountain range, Rio de Janeiro. Individuals of I. parva were captured in April 2005 using different sampling methods: time constrained search (transects), plots of 5 x 5 m (25 m²) on the litter, and pitfall traps with drift fences. We found 240 frogs; 35 females and 205 males. Females (mean SVL = 19.1 mm) were significantly larger (F1,238 = 143.016, R² = 0.375, p 0.001) than males (13.2 mm). The species preyed mainly on arthropods, with ants and isopods being the most important items, both showing high values of importance index (Ix = 50.0 and 26.7, respectively). Ischnocnema parva is a terrestrial species whose preferential microhabitat at the Serra da Concórdia was the litter of the forest floor (78.7%). The activity was predominantly crepuscular-nocturnal and the estimated density of I. parva was 24.9 ind/100 m². For the eight ovigerous females captured, the mean number of mature oocytes per female was 25 (range: 22-30) and the oocyte mean diameter was 1.11 mm (N = 40 oocytes). Oocyte number increased with female body size (R² = 0.504, F1,6 = 6.107, p 0.05, N = 8), indicating that as females increase in size they produce larger clutches. Some ecological aspects such as diet and microhabitat use were similar to that observed for an insular population of I. parva, whereas reproductive traits differed. Thus, long term studies are necessary to understand the extent to which these differences are explained by environmental factors.

9.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1503829

RESUMO

Ischnocnema (Brachycephalidae) includes many species that are important members of the leaf litter frog communities in the Atlantic Rainforest of Brazil. Ischnocnema parva (Girard, 1853) is endemic to the Atlantic Rainforest biome and is restricted to the forests of southeastern Brazil. Currently, the available information about the ecology of I. parva is scarce. We studied the diet, the habitat use, reproduction and density of I. parva in an area of Atlantic Rainforest at the Concórdia mountain range, Rio de Janeiro. Individuals of I. parva were captured in April 2005 using different sampling methods: time constrained search (transects), plots of 5 x 5 m (25 m²) on the litter, and pitfall traps with drift fences. We found 240 frogs; 35 females and 205 males. Females (mean SVL = 19.1 mm) were significantly larger (F1,238 = 143.016, R² = 0.375, p 0.001) than males (13.2 mm). The species preyed mainly on arthropods, with ants and isopods being the most important items, both showing high values of importance index (Ix = 50.0 and 26.7, respectively). Ischnocnema parva is a terrestrial species whose preferential microhabitat at the Serra da Concórdia was the litter of the forest floor (78.7%). The activity was predominantly crepuscular-nocturnal and the estimated density of I. parva was 24.9 ind/100 m². For the eight ovigerous females captured, the mean number of mature oocytes per female was 25 (range: 22-30) and the oocyte mean diameter was 1.11 mm (N = 40 oocytes). Oocyte number increased with female body size (R² = 0.504, F1,6 = 6.107, p 0.05, N = 8), indicating that as females increase in size they produce larger clutches. Some ecological aspects such as diet and microhabitat use were similar to that observed for an insular population of I. parva, whereas reproductive traits differed. Thus, long term studies are necessary to understand the extent to which these differences are explained by environmental factors.

10.
Artigo em Inglês | VETINDEX | ID: vti-690039

RESUMO

Liolaemus lutzae Mertens, 1938 is a critically endangered lizard endemic to the restinga habitat of the state of Rio de Janeiro. We surveyed 25 restinga habitats in order to locate remaining populations, evaluate the status of the species, and determine the nature of local habitat degradation. We found remnant populations of L. lutzae in 18 restinga habitats of six municipalities. The conservation status of each population varied between areas: the population of Grumari, in Rio de Janeiro municipality, is the most preserved and the population of Praia do Forte, in Cabo Frio, is the most disturbed. No L. lutzae were found in Niterói municipality. The most destructive type of habitat degradation identified was the removal of beach vegetation associated with the construction of coastal roads and/or sidewalks, destruction of the vegetation due to trampling, vehicle traffic and garbage dumping. Our data revealed that generally, beach habitats under a larger number of impact sources were those with smaller population sizes of L. lutzae. We consider that the most effective conservation measure for L. lutzae is the strict protection of its habitat, with restoration of the original beach vegetation. Finally, we recommend vegetation recovery to be followed by a program of reintroduction of the species in localities where it has been eradicated.

11.
Artigo em Inglês | VETINDEX | ID: vti-441031

RESUMO

Liolaemus lutzae Mertens, 1938 is a critically endangered lizard endemic to the restinga habitat of the state of Rio de Janeiro. We surveyed 25 restinga habitats in order to locate remaining populations, evaluate the status of the species, and determine the nature of local habitat degradation. We found remnant populations of L. lutzae in 18 restinga habitats of six municipalities. The conservation status of each population varied between areas: the population of Grumari, in Rio de Janeiro municipality, is the most preserved and the population of Praia do Forte, in Cabo Frio, is the most disturbed. No L. lutzae were found in Niterói municipality. The most destructive type of habitat degradation identified was the removal of beach vegetation associated with the construction of coastal roads and/or sidewalks, destruction of the vegetation due to trampling, vehicle traffic and garbage dumping. Our data revealed that generally, beach habitats under a larger number of impact sources were those with smaller population sizes of L. lutzae. We consider that the most effective conservation measure for L. lutzae is the strict protection of its habitat, with restoration of the original beach vegetation. Finally, we recommend vegetation recovery to be followed by a program of reintroduction of the species in localities where it has been eradicated.

12.
Artigo em Inglês | VETINDEX | ID: vti-440988

RESUMO

Data on species composition, richness, and density are presented for the leaf litter frog assemblage of an area of Atlantic Rainforest at the Serra dos Órgãos mountain range, in the state of Rio de Janeiro, southeastern Brazil. Three sampling methods were used: plot sampling, visual encounter surveys, and pitfall traps. The local assemblage of leaf litter frogs was composed of 16 species, with the direct-developing species, Euparkerella brasiliensis (Parker, 1926), being the most abundant. The estimated density of the local leaf litter frog assemblage based on plot sampling was 17.1 ind/100 m² and the estimated overall leaf litter frog mass was 684.2 g/ha. The estimated density of leaf litter frogs at the present study is the highest currently reported for Atlantic Rainforest areas, which reinforces the idea of higher densities of leaf litter frogs in the Neotropical Region compared to the Old World tropics.

13.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1503706

RESUMO

Data on species composition, richness, and density are presented for the leaf litter frog assemblage of an area of Atlantic Rainforest at the Serra dos Órgãos mountain range, in the state of Rio de Janeiro, southeastern Brazil. Three sampling methods were used: plot sampling, visual encounter surveys, and pitfall traps. The local assemblage of leaf litter frogs was composed of 16 species, with the direct-developing species, Euparkerella brasiliensis (Parker, 1926), being the most abundant. The estimated density of the local leaf litter frog assemblage based on plot sampling was 17.1 ind/100 m² and the estimated overall leaf litter frog mass was 684.2 g/ha. The estimated density of leaf litter frogs at the present study is the highest currently reported for Atlantic Rainforest areas, which reinforces the idea of higher densities of leaf litter frogs in the Neotropical Region compared to the Old World tropics.

14.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1503750

RESUMO

Liolaemus lutzae Mertens, 1938 is a critically endangered lizard endemic to the restinga habitat of the state of Rio de Janeiro. We surveyed 25 restinga habitats in order to locate remaining populations, evaluate the status of the species, and determine the nature of local habitat degradation. We found remnant populations of L. lutzae in 18 restinga habitats of six municipalities. The conservation status of each population varied between areas: the population of Grumari, in Rio de Janeiro municipality, is the most preserved and the population of Praia do Forte, in Cabo Frio, is the most disturbed. No L. lutzae were found in Niterói municipality. The most destructive type of habitat degradation identified was the removal of beach vegetation associated with the construction of coastal roads and/or sidewalks, destruction of the vegetation due to trampling, vehicle traffic and garbage dumping. Our data revealed that generally, beach habitats under a larger number of impact sources were those with smaller population sizes of L. lutzae. We consider that the most effective conservation measure for L. lutzae is the strict protection of its habitat, with restoration of the original beach vegetation. Finally, we recommend vegetation recovery to be followed by a program of reintroduction of the species in localities where it has been eradicated.

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