Resumo
The composition of the spider fauna of riparian forests is insufficiently known. These forests, adjacent to both aquatic and terrestrial environments, are recognised as having important ecosystem functions. We compare the composition of spider assemblages of four riparian forests in different drainage basins, along with their microhabitats (edges and forest interior), in the state of Rio Grande do Sul, southern Brazil. Sampling was carried out in the riparian forests of the following rivers: Piratini, municipality of Arroio Grande; Camaquã, municipality of Cristal; Sinos, municipality of Parobé, and Maquiné, municipality of Maquiné. Two samples per season were collected in two years, by sampling the tree-shrub strata with a beating tray, following fixed transects. There were six transects per drainage basin, two per microhabitat: grassland edge, forest interior and river edge. Overall, 42,057 spiders were sampled (juveniles: 79%; adults: 21%). Among the adults (8,851 individuals), we identified 440 species. Similarity analyses (ANOSIM) indicated that the araneofauna composition of the four drainage basins differ in their quantitative (Morisita) and qualitative (Simpson) similarity indexes. There were no differences in composition among microhabitats. The composition of the Maquiné River basin was the most distinct, possibly due to a greater influence of the Atlantic forest on it and a greater dominance of the Linyphiidae Sphecozone personata (Simon, 1894) (SIMPER analysis, contribution to dissimilarity: 12.15%). Differences in spider composition on large spatial scales most likely reflect regional variations in a number of environmental factors, and result in each area having in increased importance in terms of conservation.
Assuntos
Animais , Aranhas/classificação , Fauna/análise , Fauna/classificação , Florestas , Bacias FluviaisResumo
The composition of the spider fauna of riparian forests is insufficiently known. These forests, adjacent to both aquatic and terrestrial environments, are recognised as having important ecosystem functions. We compare the composition of spider assemblages of four riparian forests in different drainage basins, along with their microhabitats (edges and forest interior), in the state of Rio Grande do Sul, southern Brazil. Sampling was carried out in the riparian forests of the following rivers: Piratini, municipality of Arroio Grande; Camaquã, municipality of Cristal; Sinos, municipality of Parobé, and Maquiné, municipality of Maquiné. Two samples per season were collected in two years, by sampling the tree-shrub strata with a beating tray, following fixed transects. There were six transects per drainage basin, two per microhabitat: grassland edge, forest interior and river edge. Overall, 42,057 spiders were sampled (juveniles: 79%; adults: 21%). Among the adults (8,851 individuals), we identified 440 species. Similarity analyses (ANOSIM) indicated that the araneofauna composition of the four drainage basins differ in their quantitative (Morisita) and qualitative (Simpson) similarity indexes. There were no differences in composition among microhabitats. The composition of the Maquiné River basin was the most distinct, possibly due to a greater influence of the Atlantic forest on it and a greater dominance of the Linyphiidae Sphecozone personata (Simon, 1894) (SIMPER analysis, contribution to dissimilarity: 12.15%). Differences in spider composition on large spatial scales most likely reflect regional variations in a number of environmental factors, and result in each area having in increased importance in terms of conservation.(AU)
Assuntos
Animais , Aranhas/classificação , Florestas , Fauna/análise , Fauna/classificação , Bacias FluviaisResumo
Although thrips are known as inhabitants of flowers, they are also abundant and diverse in other microhabitats. There is an information gap concerning them, especially related to the native fauna in southern Brazil. The structure and composition of the thysanopteran community in different microhabitats was studied at the "Parque Estadual de Itapuã" (30° 22' S 51° 02' W), RS, southern Brazil. Between June 1999 and May 2001, branches (n = 1,274), flowers (n = 774), grass tussocks (n = 596) and leaf litter (n = 603) were sampled systematically in 20 points of four trails (T1 - Pedreira beach, T2 - Araçá beach, T3 - Lagoinha, and T4 - Grota hill). We found 2,197 adult thrips determined in 73 species in 41 genera, of which 37 could be nominated. Four families are represented, Thripidae, Phlaeothripidae, Heterothripidae and Merothripidae, with the first the most abundant (N = 1,599) and with the highest species richness (S = 32). The highest thrips abundance occurred in flowers N = 1,224 and the highest number of exclusive species occurred in the leaf litter (27). Frankliniella rodeos Moulton, 1933, Frankliniella gemina Bagnall, 1919 and Smicrothrips particula Hood, 1952 comprise 49.4% of the total sampled. Regarding T2, we obtained the highest abundance (N = 935) and highest species richness (S = 43). The composition of the faunas in each kind of environment proved very particular.
Embora os tripes sejam conhecidos como habitantes de flores, também são abundantes e diversos em outros micro-hábitats. Há uma lacuna de informações neste sentido, especialmente sobre a fauna nativa no Sul do Brasil. Entre junho de 1999 a maio de 2001, ramos (n = 1.274), flores (n = 774), touceiras de gramíneas (n = 596) e folhedo (n = 603) foram amostrados sistematicamente em 20 pontos de quatro trilhas (T1 - Praia da Pedreira, T2 - Praia do Araçá, T3 - Lagoinha, e T4 - Morro da Grota). Resultaram 2.197 tripes adultos determinados em 73 espécies de 41 gêneros, das quais 37 puderam ser nominadas. Quatro famílias estão representadas, Thripidae, Phlaeothripidae, Heterothripidae e Merothripidae, sendo a primeira mais abundante (N = 1.599) com a maior riqueza de espécies (S = 32). A maior abundância de tripes ocorreu nas flores (N = 1.224) e o maior número de espécies exclusivas ocorreu no folhedo (27). Frankliniella rodeos Moulton, 1933, Frankliniella gemina Bagnall, 1919 and Smicrothrips particula Hood, 1952 compõem 49,4% do total da amostra. Na T2 foi obtida maior abundância (N = 935) e maior riqueza de espécies (S = 43). A composição das faunas de cada tipo de ambiente revelou-se muito particular.
Resumo
During two consecutive years, from January 1985 to December 1986, a comparative study of mosquitoes preferences for breeding habitat was carried out in the Atlantic Forest of the Serra do Mar, Paraná State, Brazil. To achieve it, 1875 bamboo internodes aligned vertically in live green, bamboo plants Merostachys speciosa Munro and Merostachys sp. were used, in which metabolic water was exuded from the plant itself, and presenting different size/pattern holes at their lateral walls, bored by the local sylvan fauna. Another group of 1200 individual internode traps was used as comparative element, carved out with a transversal cut by a saw, filled with local stream water and held in branches at different heights in the vegetal strata nearby. At both microhabitat types, a total of 17 culicid species was registered. Culex (Microculex) neglectus Lutz, 1904, Cx. (Carrollia) soperi Antunes & Lane, 1937, Sabethes (Sabethes) batesi Lane & Cerqueira, 1942 and Sa. (Sabethinus) melanonymphe (Dyar, 1924)colonized exclusively live plant internodes, while Culex (Microculex) elongatus Rozeboom & Lane, 1950, Cx. (Carrollia) iridescens (Lutz, 1905), Cx. (Carrollia) kompi Valencia,1973and Trichoprosopon (Trichoprosopon) soaresi Dyar & Knab, 1907 bred only in internode traps. The remaining nine species colonized both habitats indistinctly. Quantitatively, was detected the abundance of 60.1% at live green internodes, against 39.9% for internode traps. Concerning the different patterns of bored live internode holes, 40.3% of the total computed specimens were collected in square or rectangular holes, 31.9% in two hole internodes, one minute circular, the other wider, and the remaining 28.8% of specimens distributed in other pattern type internodes. The mosquitoes breeding at these microhabitats fall in the culicid entomofauna specialized at locating and detecting peculiar and propitious mesogen conditions for breeding purposes.
Resumo
During two consecutive years, from January 1985 to December 1986, a comparative study of mosquitoes preferences for breeding habitat was carried out in the Atlantic Forest of the Serra do Mar, Paraná State, Brazil. To achieve it, 1875 bamboo internodes aligned vertically in live green, bamboo plants Merostachys speciosa Munro and Merostachys sp. were used, in which metabolic water was exuded from the plant itself, and presenting different size/pattern holes at their lateral walls, bored by the local sylvan fauna. Another group of 1200 individual internode traps was used as comparative element, carved out with a transversal cut by a saw, filled with local stream water and held in branches at different heights in the vegetal strata nearby. At both microhabitat types, a total of 17 culicid species was registered. Culex (Microculex) neglectus Lutz, 1904, Cx. (Carrollia) soperi Antunes & Lane, 1937, Sabethes (Sabethes) batesi Lane & Cerqueira, 1942 and Sa. (Sabethinus) melanonymphe (Dyar, 1924)colonized exclusively live plant internodes, while Culex (Microculex) elongatus Rozeboom & Lane, 1950, Cx. (Carrollia) iridescens (Lutz, 1905), Cx. (Carrollia) kompi Valencia,1973and Trichoprosopon (Trichoprosopon) soaresi Dyar & Knab, 1907 bred only in internode traps. The remaining nine species colonized both habitats indistinctly. Quantitatively, was detected the abundance of 60.1% at live green internodes, against 39.9% for internode traps. Concerning the different patterns of bored live internode holes, 40.3% of the total computed specimens were collected in square or rectangular holes, 31.9% in two hole internodes, one minute circular, the other wider, and the remaining 28.8% of specimens distributed in other pattern type internodes. The mosquitoes breeding at these microhabitats fall in the culicid entomofauna specialized at locating and detecting peculiar and propitious mesogen conditions for breeding purposes.
Resumo
During two consecutive years, from January 1985 to December 1986, a comparative study of mosquitoes preferences for breeding habitat was carried out in the Atlantic Forest of the Serra do Mar, Paraná State, Brazil. To achieve it, 1875 bamboo internodes aligned vertically in live green, bamboo plants Merostachys speciosa Munro and Merostachys sp. were used, in which metabolic water was exuded from the plant itself, and presenting different size/pattern holes at their lateral walls, bored by the local sylvan fauna. Another group of 1200 individual internode traps was used as comparative element, carved out with a transversal cut by a saw, filled with local stream water and held in branches at different heights in the vegetal strata nearby. At both microhabitat types, a total of 17 culicid species was registered. Culex (Microculex) neglectus Lutz, 1904, Cx. (Carrollia) soperi Antunes & Lane, 1937, Sabethes (Sabethes) batesi Lane & Cerqueira, 1942 and Sa. (Sabethinus) melanonymphe (Dyar, 1924)colonized exclusively live plant internodes, while Culex (Microculex) elongatus Rozeboom & Lane, 1950, Cx. (Carrollia) iridescens (Lutz, 1905), Cx. (Carrollia) kompi Valencia,1973and Trichoprosopon (Trichoprosopon) soaresi Dyar & Knab, 1907 bred only in internode traps. The remaining nine species colonized both habitats indistinctly. Quantitatively, was detected the abundance of 60.1% at live green internodes, against 39.9% for internode traps. Concerning the different patterns of bored live internode holes, 40.3% of the total computed specimens were collected in square or rectangular holes, 31.9% in two hole internodes, one minute circular, the other wider, and the remaining 28.8% of specimens distributed in other pattern type internodes. The mosquitoes breeding at these microhabitats fall in the culicid entomofauna specialized at locating and detecting peculiar and propitious mesogen conditions for breeding purposes.