115 resultados para Simulium guianense
Resumo:
This study aimed to evaluate the influence of water velocity speed on the local distribution and taxocenosis structure of blackfly larvae. The larvae were collected from two adjacent streams located in the municipality of Angra dos Reis (RJ): Caputera River and one of its tributaries. Riffle litter patches were sampled randomly using a 30 x 30 cm quadrat. Four blackfly species were found: Simulium incrustatum s. l. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax s. l. Kollar, 1832 and Simulium subpallidum s. l. Lutz, 1909. Among these species, Simulium pertinax s. l. was clearly associated with higher water current speeds, while Simulium subpallidum s. l. showed association with lower water velocities, and Simulium (Inaequalium) sp. had a relatively constant distribution along the water current gradient.
Resumo:
Fauna of Simuliidae (Diptera) from the state of Espírito Santo, Brazil: Distribution, new records and list of species. The fauna of Simuliidae in Brazil is composed of 87 species, 17 of which are recorded from the state of Espírito Santo. Entomological collections were carried out in 2010-2011 with the objective of increasing the knowledge of the species richness of this family in the state. Ninety three rivers and streams were sampled, each collection being carried out in a 50m transect. During the study period 30 species were collected, 13 of which represent new records for the state, 12 of the genus Simulium and one of the genus Lutzsimulium. Among these new state records one, Simulium lobatoi, also represents a new record from southeastern Brazil. The other newly recorded species are: Lutzsimulium hirticosta, Simulium distinctum, Simulium exiguum, Simulium oyapockense, Simulium botulibranchium, Simulium petropoliense, Simulium clavibranchium, Simulium rappae, Simulium minusculum, Simulium dinellii, Simulium ochraceum and Simulium scutistriatum.
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O objetivo deste trabalho foi avaliar a interferência da disponibilidade de luz na resposta à adubação de plantios de enriquecimento da capoeira com leguminosas arbóreas. As espécies Hymenaea courbaril, Stryphnodendron guianense, Parkia platycephala e Stryphnodendron microstachyum foram plantadas em capoeira, sob três tratamentos de fertilização: adubação orgânica, adubação orgânica acrescida de mineral e ausência de adubação. A disponibilidade de luz condicionou a resposta de P. platycephala e H. courbaril à fertilização. A aleatorização não foi suficiente para garantir condições semelhantes de luz nos plantios de enriquecimento. A variação na quantidade de luz incidente no sub‑bosque compromete a correta avaliação dos tratamentos de fertilização.
Resumo:
O objetivo deste estudo foi analisar o estoque e o crescimento em volume, biomassa, carbono e dióxido de carbono em duas áreas de Floresta Estacional Semidecidual Submontana em estágios médio e médio/avançado de sucessão da vegetação secundária. Foram utilizados dados de inventários de parcelas permanentes medidas em 2002 e 2007. Para determinar as densidades básicas da madeira e da casca das árvores, foram selecionadas espécies que apresentavam maiores porcentuais em volume e, no mínimo, cinco indivíduos. Na área em estágio médio de sucessão da vegetação secundária, os crescimentos em volume, biomassa, carbono e dióxido de carbono do estrato arbóreo foram, respectivamente, 1,49 m³.ha-1.ano-1, 0,27 tB.ha-1.ano-1, 10,13 tC.ha-1.ano-1 e 0,50 tCO2.ha-1.ano-1. A área em estágio médio avançado de sucessão apresentou 3,78 m³.ha-1.ano-1, 1,54 tB.ha-1.ano-1, 0,768 tC.ha-1.ano-1 e 2,82 tCO2.ha-1.ano-1, o que denota taxas de crescimento relativo do estoque de dióxido de carbono de 0,37% na área em estágio médio de sucessão e 1,05% na área em estágio médio avançado. As espécies com maiores estoques e crescimentos na área em estágio médio foram de Mabea fistulifera, Apuleia leiocarpa, Pouteria torta, Brosimum guianense e Pseudopiptadenia contorta e, na área em estágio médio avançado de sucessão, foram Pseudopiptadenia contorta, Mabea fistulifera, Apuleia leiocarpa, Brosimum guianense, Tapirira guianensis e Cupania oblongifolia.
Resumo:
Foi estudada uma doença em 159 ovinos em 15 propriedades localizadas em sete municípios das mesorregiões nordeste e sudeste do estado do Pará e uma em um município do estado de Roraima. Os ovinos da raça Santa Inês e seus mestiços, de ambos os sexos e com dois a quatro anos de idade, eram os mais acometidos. A doença caracterizava-se por alopecia em diversas regiões do corpo, principalmente ao redor dos olhos; essas lesões evoluíam para eritemas multifocais, pequenas pápulas e crostas. Os animais apresentavam prurido intenso no local das lesões, inquietação, perda de peso e corrimento ocular. Sempre era observada a presença de mosquitos ao redor dos animais. Com o auxílio de um puçá foi realizada a captura de insetos associados às lesões, durante o repasto nos ovinos, para a identificação. Foram identificados insetos dos gêneros Simulium e Hippelates. Realizou-se biópsia da pele lesada de 10 ovinos. As lesões histológicas se caracterizaram por leves infiltrados inflamatórios mononucleares na derme, com presença de eosinófilos. Os estudos epidemiológicos, clínicos e patológicos desses casos, bem como o descarte dos diagnósticos diferenciais, permitiram concluir que se trata de dermatite alérgica por picada de insetos.
Resumo:
Black flies are opportunistic sugar-feeders. They take sugar meals from Homopteran honeydew secretions or plant nectars, depending on availability. Homopteran honeydew secretions contain both simple and complex carbohydrates while plant nectars contain primarily simple carbohydrates. In order to determine whether honeydew secretions offer more energy than plant nectars to their insect visitors a study of wild-caught black flies was undertaken in Algonquin Provincial Park, Canada during the spring of 1 998 and 1 999. It was hypothesized that female black flies maintained on honeydew sugars will survive longer, produce more eggs and have a greater parasite vectoring potential than those maintained on artificial nectar or distilled water. Results demonstrated that: (1) host-seeking female Prosimulimfuscum/mixtum and Simulium venustum maintained on artificial honeydew did not survive longer than those maintained on artificial nectar when fed ad libitum; (2) fiiUy engorged S. venustum and Simulium rugglesi maintained on artificial honeydew did not produce more eggs than those maintained on artificial nectar when fed ad libitum; and (3) S. rugglesi did not have a greater vectoring potential of Leucocytozoon simondi when maintained on artificial honeydew as opposed to artificial nectar when fed ad libitum. However, all flies maintained on the two sugars (artificial honeydew and artificial nectar) survived longer, produce more eggs and had greater vectoring potential than those maintained on distilled water alone.
Resumo:
The sequential banding patterns of the larval salivary gland polytene chromosomes of seven species of Inseliellum (Diptera: Simuliidae) were mapped. This was completed through the comparison with the standard maps of an eighth species of Inseliellum, Simulium cataractarum. During chromosomal analysis, both fixed and floating inversions were identified. A floating inversion (IIL-l ex,2ex) revealed a cytotype within Simulium exasperans that is distributed between two islands, Moorea and Tahiti. Inversion data revealed three shared fixed inversions that could be used as phylogenetic characters. In addition, the placement of a chromosomal landmark (the nucleolar organizer, or NO) was used as a phylogenetic character. The result of a cytophylogenetic (transformational) analysis showed two groups: the NO-IL group, and the NO-IS group. A combined phylogeny was created using the published morphological data and the cytological data of the eight species. The combined tree did not differ from the morphological data only tree. Possible routes of dispersal are hypothesized using geological, chromosomal, and phylogenetic data. These data showed a general pattern of dispersal and colonization from older islands to younger islands, with one possible instance of dispersal from younger to older islands. It is postulated that inter-island speciation has allowed this dispersal and colonization, but intra-island speciation has created the diversity seen in Inseliellum.
Resumo:
Although much research has been conducted on blood-meal acquisition in adult female black flies (Diptera: Simuliidae), the same cannot be said for sugarmeals. Both sexes feed on sugar which provides energy for flight and it has been commonly held that nectar is the major carbohydrate source. This thesis addresses the question of whether a non-floral carbohydrate source, specifically homopteran honeydew, is ingested by male and female black flies. Black flies reared in the laboratory have been observed to readily ingest freshly excreted and older (dry) honeydew when presented with honeydew coated tamarack branches. Field work was conducted in Algonquin Park, Ontario in the spring and summer of 1993. Three separate studies were designed to test whether homopteran honeydew is an important carbohydrate source for black flies and whether flies from different habitats utilize different sugar sources. The sugars melezitose and / or stachyose are known to occur in a variety of homopteran honeydews and therefore were used as indicators of honeydew feeding by black flies. In the first study, black flies were collected with insect nets from a stand of Larix larcina heavily infested with honeydew - producing homopterans (Adelges lariciatus). Six black fly species were captured: Simulium venustum, S. rostra tum, S. vittatum, Stegopterna mutata, S. aureum and S. quebecense. Samples of honeydew and individual black flies were tested using thin layer chromatography (T. L. C.) with fructose, glucose, sucrose, turanose, melezitose, raffinose and stachyose as standards. All sugars except turanose and melezitose were found in the adelgid honeydew samples. Since the sugar melezitose was absent from ~ honeydew samples, stachyose was used to indicate that black flies were feeding from this particular honeydew source. Of the 201 black flies tested, 194 contained sugars which occurred in 16 combinations. Stachyose combinations excluding melezitose, present in 45.9 % of flies, were used to indicate that black flies had been feeding on the adelgid honeydew. In the second study, black flies were collected in the morning and evening on 8 collection dates, using a vehicle mounted insect net. The crops and midguts of 10 male and 10 female Simulium venustum were dissected on each sample date. In total the gut contents of 320 individual flies were analysed by T. L. C. The sugars identified from these flies were present in the following proportions: fructose (100.0%), glucose (100.0%), sucrose/turanose (50.4%), melezitose (30.3%), raffinose (18.8%) and stachyose (8.7%). These sugars occurred in fourteen different combinations. It is argued that the presence of melezitose and / or stachyose indicates that black flies had fed on homopteran honeydew. Significantly more female flies (40.0%) than male flies (27.5%) had fed on honeydew. In the third study, adult black flies were sampled by sweep netting vegetation in four habitats in the morning and evening on 8 collection dates. The habitats are as follows: (1) Davies Bog, (2) Abandoned Air Field (dominated by blueberries, Vaccinium spp.), (3) Deciduous Habitat and (4) Coniferous Habitat. Sugars in the crops and midguts of female flies were tested by T. L. C. and, for S. venustum, it was found that significantly fewer flies (18.8%) from the Air Field contained honeydew than from the other three sites (Davies Bog, 34.4%; Deciduous Habitat, 36.2%; Coniferous Habitat, 25.0%). Of the 1287 black flies tested individually by T. L. C. 441 (34.3%) contained melezitose and / or stachyose sugars indicating that this proportion of the population were feeding from Homopteran honeydew. It is therefore clear that floral (nectar) sugars are not the only source of carbohydrates available to black flies.
Resumo:
1-1 is torically, the predominan t method of reconstructing phylogenies has been through the use of morphological characters. There are new techniques now gaining acceptance, including molecular techniques al1d chromosomal information. Altl10ugh the study of behaviour has been used in a comparative framework, these analyses have, historically, been based on intuition. Hennig (1966) devised a neV\' method of reconstructing phylogenies which provided a 110ncircular method for formulating, testing and refining phylogenies. Subsequent s)Tstematists had virtually abandoned ecological and beha\lioural data as primary indicators of phylogenetic relationships (Brooks and McLennan 1991). Therefore, in a modern cladistic framework (sensu Hennig) the analysis of behavioural traits remains underrepresented as a method of reconstructing phylogenies. This thesis will reconstruct the phylogeny for species of black flies (Diptera: Simuliidae), using two steps. The first step is to thoroughl)' understand and explain the cocoon spinning in black fly larvae. There have bee115 previous descriptions of cocoon spinning, but all were incomplete or erroneous. The advances in technology, including video recorders and VCRs, have allowed this behaviour to be analyzed in great detail in 20 different species. A complete description of the cocoon spinning of Simulium \littatum is given. This description will be used as a template for the other species observed. The description and understanding of cococ)n spinning was the first step in undertaking a phylogenetic analysis using this behaviour. The behaviour was then broken down and analyzed, revealing 23 characters, 3 either qualitative and quantitative in nature. These characters were assessed in a cladistic framework (sensu Hennig) and a phylogenetic tree was reconstructed with a e.I of 0.91 and an R.I. of 0.96. This phylogenetic tree closely resembles a previously established pllylogenetic tree produced from morphological and cytological information. The importance of this result is the indication that, contrary to some authors, behavioural characters, if used properly, can add very informative characters to a data set.
Resumo:
The sugar-feeding ecology of dipteran vectors has recently been targeted because it presents opportunities to inoculate common food sources for these dipterans with entomopathogenic bacteria as a means of controlling the population of host-seeking adult dipteran vectors. Whereas this approach to vector control holds some promise, differences in the nutrient composition and concentration in sugary food sources can influence the food selection pattern of dipteran vectors and potentially confound the outcomes of field trials on the efficacy of entomopathogenic bacteria as vector control agents. Further, nutrient components of bacteria-inoculated artificial diets may present unintended effects of extending the survivorship or fecundity of the target population and potentially render the whole approach counterproductive. The present study investigated the diet-specific factors that influence the foraging decisions of female Simulium venustum/verecundum (Diptera: Simuliidae) and female Anopheles stephensi (Diptera: Culicidae) on artificial nectar and honeydew. Paired choice experiments showed that the black flies forage more frequently from high calorie diets, which contained melezitose, or those diets that contained amino acids, compared to low calorie melezitose-free diets or amino acid-free diets. The mosquitoes however displayed a more random diet selection pattern. The effects of sugary diets on certain life-history traits considered to be important to the ecological fitness of the black flies and mosquitoes were also investigated. Sugary diets had no significant effect on the survivorship and fecundity of the black flies, but they influenced the resistance of Leucocytozoon-infected flies to the parasite. Amino acid-containing diets appeared to extend the survival of mosquitoes, and also allowed them to take more vertebrate blood when they blood fed.
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The genome sequence of Aedes aegypti was recently reported. A significant amount of Expressed Sequence Tags (ESTs) were sequenced to aid in the gene prediction process. In the present work we describe an integrated analysis of the genomic and EST data, focusing on genes with preferential expression in larvae (LG), adults (AG) and in both stages (SG). A total of 913 genes (5.4% of the transcript complement) are LG, including ion transporters and cuticle proteins that are important for ion homeostasis and defense. From a starting set of 245 genes encoding the trypsin domain, we identified 66 putative LG, AG, and SG trypsins by manual curation. Phylogenetic analyses showed that AG trypsins are divergent from their larval counterparts (LG), grouping with blood-induced trypsins from Anopheles gambiae and Simulium vittatum. These results support the hypothesis that blood-feeding arose only once, in the ancestral Culicomorpha. Peritrophins are proteins that interlock chitin fibrils to form the peritrophic membrane (PM) that compartmentalizes the food in the midgut. These proteins are recognized by having chitin-binding domains with 6 conserved Cys and may also present mucin-like domains (regions expected to be highly O-glycosylated). PM may be formed by a ring of cells (type 2, seen in Ae. aegypti larvae and Drosophila melanogaster) or by most midgut cells (type 1, found in Ae. aegypti adult and Tribolium castaneum). LG and D. melanogaster peritrophins have more complex domain structures than AG and T. castaneum peritrophins. Furthermore, mucin-like domains of peritrophins from T. castaneum (feeding on rough food) are lengthier than those of adult Ae. aegypti (blood-feeding). This suggests, for the first time, that type 1 and type 2 PM may have variable molecular architectures determined by different peritrophins and/or ancillary proteins, which may be partly modulated by diet.
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Gynocraterium Bremek. é um gênero monotípico descrito para a Guiana e só recentemente citado para outros países sulamericanos. Com base na análise das coleções de 52 herbários nacionais e estrangeiros, verificou-se a ocorrência do táxon em novas localidades, inclusive na Amazônia brasileira. Uma revisão do gênero nos neotrópicos é apresentada, incluindo ratificações nas descrições do mesmo e de Gynocraterium guianense Bremek. Aspectos morfológicos desta espécie são ilustrados pela primeira vez, assim como os grãos de pólen descritos e fotografados através de microscopia eletrônica de varredura. São ainda apresentados aspectos diagnósticos, fenológicos e atualizações sobre a distribuição de G. guianense, que é restrita a região amazônica.
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Reproduction and feeding aspects of Neoplecostomus microps (Loricariidae, Neoplecostominae) in the Ribeirao Grande system, eastern Serra da Mantiqueira (São Paulo State). The Ribeirao Grande system is located in the slope of the Serra da Mantiqueira and is surrounded by Atlantic forest. Eight sites were surveyed in the Ribeirao Grande system, during the winter (July 2001), spring (October 2001), summer (February 2002) and fall (April 2002). Samples were made with an electrofishing device. Gonad maturation, levels of stomach fullness and fat content were analyzed and their distributions reported in an annual cycle. Neoplecostomus microps has a spawning in the spring through to summer. The size at sexual maturity is about 5.9 cm total length for males and 6.9 cm for females. The high values in October and February by the gonadosomatic index and the relative condition factor coincided with the spawning period. In the diet of N. microps were found Diptera larvae (Simulium, Chironomus), Plecoptera nymphs and Coleoptera aquatic Larvae (Psephenus). The increased feeding from summer to fall provided fat accumulation. During subsequent seasons, fish may utilize visceral fat reserves for maintenance and reproduction. The reproductive pattern and feeding are interpreted as being an adaptation with respect to temporal and spatial variation and food availability.
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O objeto de estudo desta pesquisa são as relações de trabalho de brasileiros na Guiana Francesa, abordada por uma etnografia sobre a inserção dos imigrantes no mercado de trabalho local. Nesta pesquisa, em linhas gerais, realizamos uma reflexão sobre como as migrações internacionais, em tempos de globalização, colaboram para desenraizar, excluir e incluir marginalmente milhares de trabalhadores brasileiros, que atuam no mercado de trabalho guianense. O aumento do desemprego em escala mundial, a exigência de qualificação, a dificuldade temporal da reinclusão, a inclusão marginal, as formas precárias de trabalho, os dilemas étnicos, o rebaixamento da média salarial nos espaços de imigrantes ilegais, a terceirização/subcontratação do trabalho e o aumento da feminização das migrações foram os eixos analíticos importantes desta tese. Este trabalho primeiramente recupera o debate sobre as migrações internacionais, o processo de globalização e as mudanças no mundo do trabalho. A pesquisa reconstruiu a história das primeiras migrações de trabalhadores de brasileiros para a Guiana Francesa na metade da década de 60 do século XX, além de apresentar e abrir uma discussão sobre a própria sociedade guianense. Neste sentido, recuperamos a história das relações sociais de uma sociedade que ainda busca uma identidade nacional/regional. No entanto, de uma forma mais específica, examinamos as relações de trabalho dos imigrantes brasileiros na Guiana Francesa, lançando um olhar em diversas temáticas que cruzam este fenômeno, a saber: globalização, clandestinidade, e direitos humanos. Finalmente, numa perspectiva de síntese, tentamos dimensionar o que é ser imigrante ilegal na Guiana Francesa e qual a conseqüência desse fato nas relações de trabalho dos brasileiros neste Departamento Francês?. Na tentativa de construir uma sociologia da clandestinidade, esta tese investiu numa possibilidade real de reflexão sobre o nosso tempo-presente, recheado de contradições raciais, econômicas, políticas, culturais e sociais.
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Foi estudada uma doença em 159 ovinos em 15 propriedades localizadas em sete municípios das mesorregiões nordeste e sudeste do estado do Pará e uma em um município do estado de Roraima. Os ovinos da raça Santa Inês e seus mestiços, de ambos os sexos e com dois a quatro anos de idade, eram os mais acometidos. A doença caracterizava-se por alopecia em diversas regiões do corpo, principalmente ao redor dos olhos; essas lesões evoluíam para eritemas multifocais, pequenas pápulas e crostas. Os animais apresentavam prurido intenso no local das lesões, inquietação, perda de peso e corrimento ocular. Sempre era observada a presença de mosquitos ao redor dos animais. Com o auxílio de um puçá foi realizada a captura de insetos associados às lesões, durante o repasto nos ovinos, para a identificação. Foram identificados insetos dos gêneros Simulium e Hippelates. Realizou-se biópsia da pele lesada de 10 ovinos. As lesões histológicas se caracterizaram por leves infiltrados inflamatórios mononucleares na derme, com presença de eosinófilos. Os estudos epidemiológicos, clínicos e patológicos desses casos, bem como o descarte dos diagnósticos diferenciais, permitiram concluir que se trata de dermatite alérgica por picada de insetos.