85 resultados para species richness estimation
Resumo:
Canine American visceral leishmaniasis and American cutaneous leishmaniasis (ACL) cases have been recorded in Espírito Santo do Pinhal. The aim of this study was to gather knowledge of the sand fly community and its population ecology within the municipality. Captures were made weekly over a period of 15 months in the urban, periurban and rural areas of the municipality, using automatic light traps. A total of 5,562 sand flies were collected, comprising 17 species. The most abundant species were Nyssomyia whitmani and Pintomyia pessoai in the rural area, Lutzomyia longipalpis and Ny. whitmani in the periurban area and Lu. longipalpis in the urban area. The highest species richness and greatest index species diversity were found in the rural area. The similarity index showed that urban and periurban areas were most alike. Lu. longipalpis was found in great numbers during both dry and humid periods. The presence of dogs infected with Leishmania infantum chagasi in the urban area indicates a high risk for the establishment of the disease in the region. A high abundance of Ny. whitmani and Pi. pessoai in the rural and periurban areas indicates the possibility of new cases of ACL occurring in and spreading to the periurban area of Espírito Santo do Pinhal.
Resumo:
We describe the abiotic factors affecting the distribution of black flies at a microhabitat scale, rather than at the regional scale usually present in the literature on the Neotropics. Black fly larvae were sampled from the Tocantins River and three tributaries, located in the Brazilian savanna (state of Tocantins, Brazil) during six bi-monthly sampling periods from October 2004-August 2005. At each sampling site, 15 random quadrats (30 x 30 cm) were sampled each period and for each quadrat were determined mean water velocity, predominant substrate type (rocks, riffle litter or riparian vegetation) and depth detrended correspondence analysis (DCA) was used to determine associations with current velocity, whereas correspondence analysis (CA) was used to estimate site specific current velocity associations. Canonical correspondence analysis (CCA) was used to identify general microhabitat associations. The CCA showed that most species had a trend towards riffle litter, except for Simulium nigrimanum associated with rocky substrate and Simulium cuasiexiguum associated with riparian vegetation. The DCA showed a well defined pattern of water velocity associations. The CA revealed that the species showed different speed associations from one site to another, suggesting different competitive pressures resulting in the occurrence of different realized niches.
Resumo:
This study reports the distribution, ecotopes and fauna diversity of sandflies captured in five training bases on a military reserve in Manaus, state of Amazonas (AM). A total of 10,762 specimens were collected, which were distributed among 58 species, with the highest number recorded at Base Instruction 1 (BI1). A higher rate of species richness was found at the Base Instruction Boina Rajada and low levels of diversity associated with a high abundance index with the clear dominance of Lutzomyia umbratilis, Lutzomyia ruii and Lutzomyia anduzei were found at BI1. The abundance of Lu. umbratilis raises the possibility of outbreaks of American cutaneous leishmaniasis by the main vector of the disease in AM.
Resumo:
In several countries, surveillance of insect vectors is accomplished with automatic traps. This study addressed the performance of Mosquito Magnet® Independence (MMI) in comparison with those of CDC with CO2 and lactic acid (CDC-A) and CDC light trap (CDC-LT). The collection sites were in a rural region located in a fragment of secondary tropical Atlantic rainforest, southeastern Brazil. Limatus durhami and Limatus flavisetosus were the dominant species in the MMI, whereas Ochlerotatus scapularis was most abundant in CDC-A. Culex ribeirensis and Culex sacchettae were dominant species in the CDC-LT. Comparisons among traps were based on diversity indices. Results from the diversity analyses showed that the MMI captured a higher abundance of mosquitoes and that the species richness estimated with it was higher than with CDC-LT. Contrasting, difference between MMI and CDC-A was not statistically significant. Consequently, the latter trap seems to be both an alternative for the MMI and complementary to it for ecological studies and entomological surveillance.
Resumo:
Chagas disease is one of the most important yet neglected parasitic diseases in Mexico and is transmitted by Triatominae. Nineteen of the 31 Mexican triatomine species have been consistently found to invade human houses and all have been found to be naturally infected with Trypanosoma cruzi. The present paper aims to produce a state-of-knowledge atlas of Mexican triatomines and analyse their geographic associations with T. cruzi, human demographics and landscape modification. Ecological niche models (ENMs) were constructed for the 19 species with more than 10 records in North America, as well as for T. cruzi. The 2010 Mexican national census and the 2007 National Forestry Inventory were used to analyse overlap patterns with ENMs. Niche breadth was greatest in species from the semiarid Nearctic Region, whereas species richness was associated with topographic heterogeneity in the Neotropical Region, particularly along the Pacific Coast. Three species,Triatoma longipennis, Triatoma mexicana and Triatoma barberi, overlapped with the greatest numbers of human communities, but these communities had the lowest rural/urban population ratios. Triatomine vectors have urbanised in most regions, demonstrating a high tolerance to human-modified habitats and broadened historical ranges, exposing more than 88% of the Mexican population and leaving few areas in Mexico without the potential for T. cruzitransmission.
Resumo:
The Ichneumonidae (Hymenoptera) of the Estação Ecológica of the Universidade Federal de Minas Gerais, Belo Horizonte, with emphasis on the Pimplinae species. In one annual cycle 83,712 insects were captured, of which 2,339 were Ichneumonidae, belonging to 17 subfamilies; they were collected by a Malaise trap placed in a montane semidecidual seasonal forest, inside the campus. Among the collected ichneumonids there were 13 genera and 30 species of Pimplinae, of which Pimpla croceiventris was the most frequent species. The species richness of Pimplinae was greater in the ecological station in Belo Horizonte, MG than in other localities studied.
Resumo:
During two years, from August 1986 to July 1988, the entomofauna of some preserved areas of Parana State, southern Brazil, was sampled in a project called "Levantamento da Fauna Entomológica no Estado do Paraná (PROFAUPAR)". Specimens of Muscidae (Diptera) were sorted out from the material collected using Malaise traps in three of the eight sites sampled (Colombo, Ponta Grossa and Guarapuava) in the first year (August 1986 to July 1987). A total of 7,014 specimens of Muscidae was captured and 91 species were identified. Neodexiopsis flavipalpis Albuquerque was the most abundant species in Ponta Grossa (672 specimens) and in Guarapuava (332 specimens). For Colombo, the most abundant species was Neodexiopsis vulgaris Couri & Albuquerque (172 specimens). The highest richness of species and abundance were observed in Ponta Grossa (77 and 3,559 respectively). The total number of specimens and means values of capture were analyzed. Indices of diversity and evenness were used to discuss richness and dominance of species in each locality. Besides using ecological indices, species richness estimators were also used.
Resumo:
Fire represents an important disturbance to ant communities in areas of fire regime. Otherwise, little is known about the effects of fire on ant communities in areas of non-fire regimes, such as in the Amazonian region. We evaluated the long-term effect of fire on ant species richness in a rain forest (Bacaba Plateau) burned 15-years ago and compare our data with the data of primary unburned forest. A total of 85 ant species distributed in 21 genera and 14 tribes were collected; among them, 72 and 44 species were found on the litter and vegetation, respectively. The fire damaged forest studied supports an intermediate richness of ants when compared to a primary unburned rain forest in the same region. A comparative analysis of ant species richness showed that the Bacaba Plateau presented a different ant fauna when compared with the primary unburned forests, suggesting that fire can alter ant species composition. Although, our results cannot be conclusive on the effects of fire on ant community, they represent a pioneer data on human induced fire in tropical rain forests.
Resumo:
Riparian forests are important features of any ecosystem, especially on grassland and savannah vegetation types. However, riparian forests in southernmost Brazil have received much less attention than elsewhere. This is the first quantitative study of pentatomoid (Hemiptera) diversity in the Pampa biome, surveying riparian forests of brooks and rivers in the environs of the municipality of Bagé, Rio Grande do Sul state, southern Brazil. The aim was two-fold: taxonomic characterization of the fauna and a primary ecological study of bug diversity. Sweeping net and beating tray were used to sample trees and shrubs on the border of sampling sites; sampling was carried out during three consecutive days, from March 28th to 30th 2006. Overall 154 individuals of 32 species of Pentatomoidea were captured, almost all species are new records for the local fauna. Taller forest canopy sites had higher abundance overall and higher species richness than shorter forest canopy sites. Of the 32 species, 11 were singletons and four were doubletons. There were no differences for pentatomoid species composition between the two environments differing in vegetation structure. Association to the Pampa biome of the most abundant species found are discussed. Although based on a rapid assessment protocol of faunal inventories, our results add important bioecological information to the pentatomoid fauna of the Pampa biome, especially associated to riparian forests.
Resumo:
Ants are among the most common arthropods that colonize termite nests. The aim of this study was to identify the ant fauna associated to termite nests found in a cacao plantation in the county of Ilhéus, Bahia, Brazil, with emphasis on the fauna that uses the nests as foraging and/or nesting environment. For this purpose, 34 active, decadent and abandoned nests of Nasutitermes corniger, N. ephratae and Nasutitermes sp., with different volumes and degrees of activity, were dissected. A total of 54 ant species, belonging to 23 genera and five subfamilies, was found in the constructions. The active, decadent and abandoned termite nests presented, respectively, six, eight and 48 ant species. Crematogaster acuta and Ectatomma tuberculatum were the most frequent species in the active and decadent nests, respectively, while the most frequent species in the abandoned nests were Solenopsis pollux, Thaumatomyrmex contumax and Thaumatomyrmex sp. Twenty-six ant species had true colonies within the termitaria. The Formicidae species richness in the nests was inversely related to the degree of termite activity in the nests. The occurrence of living, decadent or abandoned termitaria of Nasutitermes spp. in cacao plantations foments the heterogeneity of habitats available in the plantations and favors the maintenance of high diversity of organisms that use obligatory or opportunistically this substrate.
Resumo:
Butterflies (Lepidoptera, Papilionoidea and Hesperioidea) of the "Baixada Santista" region, coastal São Paulo, southeastern Brazil. A list with 538 species of butterflies recorded in the Baixada Santista, São Paulo ( SE Brazil) is presented. Standard sampling protocols (i.e. with entomological nets) were followed. Baited traps were installed for fruit feeding species. Data from the literature and entomological collections were also considered in the total estimated species richness. The species richness recorded in the Baixada Santista region represents about 16% of the Brazilian butterfly fauna, and 34% of the known butterfly fauna for the state of São Paulo. The present list contains an appreciably higher number of species in comparison to other lists from similar biomes farther south, such as Blumenau in Santa Catarina, and Maquiné in Rio Grande do Sul.
Resumo:
Diversity of Odonata (Insecta) in lotic systems from Serra da Bodoquena, Mato Grosso do Sul State, Brazil. A systematic survey was carried out in four lotic systems from Serra da Bodoquena, the largest natural forests of the State, from August 2007 to November 2008. 548 specimens belonging to 33 species, distributed in 5 families were sampled. Libellulidae was dominant, with 13 species, followed by Gomphidae, Coenagrionidae, Protoneuridae and Calopterygidae.
Resumo:
Termites are abundant organisms in tropical ecosystems and strongly influence the litter decomposition and soil formation. Despite their importance, few studies about their assemblage structures have been made in Brazilian Atlantic Forest fragments, especially in the area located north of the São Francisco River. This study aims to analyze the assemblage composition of five Atlantic Forest fragments located in the northern biome limit along the Brazilian coast. A standardized sampling protocol of termites was applied in each fragment. Thirty-three termite species belonging to twenty genera and three families were found in the forest fragments. The wood-feeder group was dominant both concerning to species richness and number of encounters in all areas. In sites northern to 7°S, there is an evident simplification of the termite assemblage composition regarding species richness and number of encounters by feeding group. This fact is apparently due to a higher sandy level in soils and to semideciduous character of the vegetation in the northern fragments. Thus, even on the north of São Francisco River, termite biodiversity is heterogeneously spread with highest density of species in the portion between 07°S and São Francisco River mouth (10°29'S).
Resumo:
Orthoptera assemblages associated with macrophytes of floodplain lakes of the Paraná River. The Orthoptera assemblage composition varies considerably, depending on habitat type. This study examines the spatiotemporal relationship between plant diversity, hydrometric level, environmental variables and the Orthoptera richness and abundance in floodplain lakes connected permanently or temporarily with the main channel of the Paraná River. The grasshoppers were collected fortnightly (April 2006May 2007). A total of 17 species were recorded and classified according to their frequency of occurrence in constant (7), accessory (4), or accidental (6) species. In the two lakes, the greater species richness and abundance was recorded in summer, thereby coinciding with the highest water level of the Paraná River. The most significant correlation between the orthopteran richness and abundance was with the water level. The aquatic plant richness was significantly different between the lakes, but the vegetation was dominated by Eichhornia crassipes (Mart.) Solms. (Liliales, Pontederiaceae). The lake, which was connected permanently, presented the highest values of diversity and abundance, proving to be a more diverse assemblage. The beta diversity was higher in the temporary connected lake than in the permanently connected one. The orthopterans assemblages were different between the lakes, Cornops aquaticum and Tucayaca gracilis were the species that contributed more to the level of dissimilarity. C. aquaticum was more representative in the lake temporarily connected, while T. gracilis in the permanent connected one. The water level of the Paraná River and the connectivity of the floodplain lakes play an important role to explain the abundance and richness of their orthopteran assemblages.
Resumo:
Comparative abundance and diversity of Dryininae (Hymenoptera, Dryinidae) in three savannah phytophysiognomies in southeastern Brazil, under three sampling methods. This study aimed to assess the abundance and diversity of Dryininae in riparian vegetation, Brazilian savannah, and savannah woodland vegetation at the Estação Ecológica de Jataí, in Luiz Antônio, State of São Paulo, Brazil, by using Moericke, Malaise, and light traps. The sampling was carried out from December 2006 to November 2009, and 371 specimens of Dryininae were caught, with the highest frequencies in spring and summer. Fourteen species of Dryinus Latreille, 1804 and one of Thaumatodryinus Perkins, 1905 were identified. The highest frequencies of Dryinus in the riparian vegetation differed significantly from those obtained in the Brazilian savannah and savannah woodland vegetation. In the riparian vegetation, the highest number of Dryinus was collected using light traps and the interactions between abundance and the collection method used were significant. The number of specimens of Dryinus collected in the Brazilian savannah and savannah woodland vegetation using Malaise traps did not differ significantly from those obtained using Moericke traps. Males significantly outnumbered females in the sex ratio of Dryinus. The species diversity of Dryinus based on females collected using Malaise traps was high in the Brazilian savannah. Furthermore, high species richness of female Dryinus was observed in riparian vegetation (six species) and Brazilian savannah (five). The light trap was the most successful method for sampling diversity of Dryininae.