35 resultados para Cicada


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Detailed investigations on the structural and mechanical properties of the forewing of the cicada were carried out. Measurement of the structures of the wings showed that the thickness of the membrane of each cell and the diameter of each vein were non-uniform in both the longitudinal and transverse directions, and their means were approximately 12.2 and 133.3 mum, respectively. However, the aspect ratios of the wings and the bodies were quite uniform and were approximately equal to 2.98 and 2.13, respectively. Based on the measured thickness, mass and area of the membranes of the cells, the mean density and the mean area density of the wing were approximately 2.3 g cm(-3) and 2.8 x 10(-3) g cm(-2), respectively. In addition, the diameters of the veins of the wings, including the diameters of the holes in the vein of the leading edge, were examined. The mechanical properties of the wing were investigated separately by nanoindentation and tensile testing. The results indicated that the mean Young's modulus, hardness and yield stress of the membranes of the wings were approximately 3.7 Gpa, 0.2 Gpa and 29 Mpa, respectively, and the mean Young's modulus and strength of the veins along the direction of the venation of wings were approximately 1.9 Gpa and 52 Mpa, respectively. Finally, the relevant results were briefly analyzed and discussed, providing a guideline to the biomimetic design of the aerofoil materials of micro air vehicles.

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The genus Fidicinoides Boulard & Martinelli is characterized by its partially exposed timbal, not totally covered by the meta-scutellar plate as occurs in Fidicina Amyot & Serville, and has an extensive geographic distribution in Central and South America. In this work a new species for the genus is described. Fidicinoides sarutaiensis Santos, Martinelli & Maccagnan sp. n. is a medium-sized cicada, with the collected and studied specimens associated with coffee (Coffee arabica L.), in the municipality of Sarutaia, in the southeast region of São Paulo state. The species F. glauca (Goding, 1925) and F. viridifemur (Walker, 1850) are transferred to Dorisiana. An identification key for the Fidicinoides species of Brazil is also proposed.

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Little cicadas are homopteran insect pests of sugarcane plantations. As these insects suck out the sap from the leaf parenchyma, they inoculate a toxic saliva that damages the plant vessels, thus promoting the loss of glucose by the affected plant. The morphological and histological analyses of the salivary glands of the little cicada Mahanarva posticata, revealed that these glands are formed by 2 portions: one portion comprises a group of acini and has been denominated as the principal gland; the second portion is filamentous in nature and has been denominated as the accessory gland; it is formed by very long and fine filaments. The acinous portion of the gland can be subdivided into 2 lobes: an anterior lobe formed by 3 lobules (I, II, III), and a posterior lobe formed by lobule IV and the excretory duct. Histologically, the salivary glands showed that the filaments are empty sutructures composed by several internal channels with secretion granules being observed in the cytoplasm of the cells of the secretory filaments. Lobules I and II of the principal gland are characterized by being highly basophilic and for accumulating a large amount of secretion in both the cytoplasm of the cells and inside secretion vesicles. Histochemically, we verified that the secretion produced by these glands is lipidic and protein in nature, with the production of polysaccharides being very low. The differences in stain and appearance of the different regions of the salivary gland lead us to believe that the final glandular product is lipoproteic in nature.

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Fidicinoides picea (Walker, 1850) and Fidicinoides poulaini Boulard and Martinelli, 1996 are recorded for the first time from the state of Mato Grosso, extending the known distribution of these species to the south. Thereby, the number of Fidicinoides species from Mato Grosso is increased to nine, being Mato Grosso the state with the largest number of recorded species of this genus in Brazil. © 2012 Check List and Authors.

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DNA Barcoding (Hebert et al. 2003) has the potential to revolutionize the process of identifying and cataloguing biodiversity; however, significant controversy surrounds some of the proposed applications. In the seven years since DNA barcoding was introduced, the Web of Science records more than 600 studies that have weighed the pros and cons of this procedure. Unfortunately, the scientific community has been unable to come to any consensus on what threshold to use to differentiate species or even whether the barcoding region provides enough information to serve as an accurate species identification tool. The purpose of my thesis is to analyze mitochondrial DNA (mtDNA) barcoding’s potential to identify known species and provide a well-resolved phylogeny for the New Zealand cicada genus Kikihia. In order to do this, I created a phylogenetic tree for species in the genus Kikihia based solely on the barcoding region and compared it to a phylogeny previously created by Marshall et al. (2008) that benefits from information from other mtDNA and nuclear genes as well as species-specific song data. I determined how well the barcoding region delimits species that have been recognized based on morphology and song. In addition, I looked at the effect of sampling on the success of barcoding studies. I analyzed subsets of a larger, more densely sampled dataset for the Kikihia Muta Group to determine which aspects of my sampling strategy led to the most accurate identifications. Since DNA barcoding would by definition have problems in diagnosing hybrid individuals, I studied two species (K. “murihikua” and K. angusta) that are known to hybridize. Individuals that were not obvious hybrids (determined by morphology) were selected for the case study. Phylogenetic analysis of the barcoding region revealed insights into the reasons these two species could not be successfully differentiated using barcoding alone.

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Interpreting acoustic recordings of the natural environment is an increasingly important technique for ecologists wishing to monitor terrestrial ecosystems. Technological advances make it possible to accumulate many more recordings than can be listened to or interpreted, thereby necessitating automated assistance to identify elements in the soundscape. In this paper we examine the problem of estimating avian species richness by sampling from very long acoustic recordings. We work with data recorded under natural conditions and with all the attendant problems of undefined and unconstrained acoustic content (such as wind, rain, traffic, etc.) which can mask content of interest (in our case, bird calls). We describe 14 acoustic indices calculated at one minute resolution for the duration of a 24 hour recording. An acoustic index is a statistic that summarizes some aspect of the structure and distribution of acoustic energy and information in a recording. Some of the indices we calculate are standard (e.g. signal-to-noise ratio), some have been reported useful for the detection of bioacoustic activity (e.g. temporal and spectral entropies) and some are directed to avian sources (spectral persistence of whistles). We rank the one minute segments of a 24 hour recording in descending order according to an "acoustic richness" score which is derived from a single index or a weighted combination of two or more. We describe combinations of indices which lead to more efficient estimates of species richness than random sampling from the same recording, where efficiency is defined as total species identified for given listening effort. Using random sampling, we achieve a 53% increase in species recognized over traditional field surveys and an increase of 87% using combinations of indices to direct the sampling. We also demonstrate how combinations of the same indices can be used to detect long duration acoustic events (such as heavy rain and cicada chorus) and to construct long duration (24 h) spectrograms.

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PaceXL is a statistics add-in that works inside Microsoft® Excel.

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The diet of long-nosed bandicoots (Perameles nasuta) on the central coast of New South Wales, Australia, was examined over two summers and two winters using a combination of faecal scat analysis for food fragments and stable isotope analysis (ratios of 13C/12C and 15N/14N) of blood. Isotope ratios in blood overlapped most strongly with those in invertebrate prey, and varied much less between seasons than did those in most dietary items, suggesting that the assimilated diet of long-nosed bandicoots is dominated by invertebrates throughout the year. Invertebrate remains dominated collected faeces in both seasons, even though the availability of invertebrate prey was higher in summer. Thus both techniques indicated that long-nosed bandicoots were primarily insectivorous year-round. Faecal scat analysis indicated that invertebrate eggs were more abundant in summer than winter. At a finer scale, spiders, orthopterans, lepidopteran larvae, ants, leaf material (non-grass monocot) and seeds were more abundant in summer, while cicada larvae, roots, fungi, grass leaves and Acacia bract (small modified leaves appearing as scales) were more abundant in winter. Subterranean foods (cicada larvae, plant roots and hypogeous fungi) were more abundant in winter and more abundant in the diet of males than of either lactating or non-lactating females.

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Trata-se do primeiro registro de ocorrência de Guyalna cuta (Walker) (Hemiptera: Cicadidae) em pinhão-manso, Jatropha curcas L. (Euphorbiaceae) no Estado de Mato Grosso do Sul. Adultos desse inseto foram observados na parte aérea da planta, durante novembro e dezembro de 2008 e de 2009. em Mato Grosso do Sul, existem plantios comerciais e experimentais do pinhão-manso, tornando-se necessários estudos relacionados a este inseto, a fim de prevenir eventuais danos à cultura.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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É apresentada a distribuição de 10 espécies de cigarras associadas ao cafeeiro, Coffea arabica, nos Estados de Minas Gerais, São Paulo e Paraná, Brasil. A informação sobre a distribuição geográfica destas espécies no Continente Americano, afora o Brasil, foi baseada na literatura. Para o Brasil, as localidades de ocorrência de cigarras foram baseadas na literatura, nos levantamentos realizados e em exemplares de coleções nacionais. Outros sete hospedeiros, além do cafeeiro, foram também registrados: esponjeira (Acacia farnesiana), sibipiruna (Caesalpinia peltophoroides), Cassia spp., amoreira (Morus alba), abacateiro (Persea americana), angico (Piptadenia sp.) e cacaueiro (Theobroma cacao). São apresentadas chaves de identificação, baseadas nas características gerais e na genitália masculina.

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Branches of coffee-plant were collected in Sao Sebastiao do Paraiso County, Minas Gerais State, at the Experimental Station of the Agricultural Research Company (Empresa de Pesquisa Agropecuaria de Minas Gerais - EPAMIG), with the aim of studying various aspects of oviposition by Quesada gigas (Hemiptera: Cicadidae). The number of branches with Q. gigas egg nests was analyzed, as well as the number of nests per branch, the eggs per nest and the diameter of the egg nest location on the branch. The preference for oviposition either on alive or dry branches and the size of the egg were assessed. Egg-laying occurred only on dry branches. The mean of the branch diameter on which the egg nests occurred was 2.5 +/- 0.53 mm. The number of eggs per nest averaged 13.2 +/- 4.9, and the number of egg nests per branch was 2.2 +/- 1.74. The eggs were 1.9 +/- 0.08 mm long by 0.5 +/- 0.04 mm wide. The largest diameters of the branches containing egg nests were found on the upper third of the trees, as well as the greatest amount of branches with egg nests, of egg nests per branch and of eggs per nest. The correlation relationship between all of the experiment variables was positive.