The night and day of dung beetles (Coleoptera, Scarabaeidae) in the Serra do Japi, Brazil: elytra colour related to daily activity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of carrion smell and rebaiting time on the efficiency of pitfall traps to dung beetle sampling

Dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) are very useful insects, as they improve the chemo-physical properties of soil, clean pastures from dung pads, and help control symbovine flies associated with bovine cattle. Their importance makes it fundamental to sample and survey them adequately. The objectives of the present study were to determine the influence of decaying insects trapped in pitfalls on the attractiveness of Moura pig Sus scrofa L. (Suidae) and collared peccary Tayassu tajacu (L.) (Tayassuidae) dung used as baits to lure dung beetles, and to establish how long these baits remain attractive to dung beetles when used in these traps. Some dung beetle species seemed to be able to discriminate against foul smell from decaying insects within the first 24 h, hence decreasing trap efficiency. This was more evident in peccary dung-baited traps, which proved to be the least attractive bait. Attractiveness lasted only 24 h for peccary dung, after which it became unattractive, whereas the pig dung bait was highly attractive for 48 h, after which its attractiveness diminished but was not completely lost.

Seasonal and spatial species richness variation of dung beetle (Coleoptera, Scarabaeidae s. str.) in the Atlantic Forest of southeastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Selective defaunation affects dung beetle communities in continuous Atlantic rainforest

Overhunting has caused severe decline or local extinction in many large-bodied mammals with direct consequences on plant regeneration, yet little is known about indirect impacts of selective defaunation on commensal species. Cascading effects of species extinction across dependent species groups are likely to occur in coprophagous beetles, because these invertebrates rely on mammal dung for food and nesting material. Both mammals and dung beetles provide important ecosystem services and cascading effects are likely to lead to rapid functional losses. In this study, we described changes in dung beetle communities across a gradient of selective defaunation in continuous Brazilian Atlantic rain forest. We compared the dung beetle assemblages in seven sites with different mammalian biomass and composition. The reduction in the mammalian biomass had a major effect on dung beetle communities by (1) increasing dung beetle abundance with decreasing overall mammal, primate and large mammal biomasses, (2) decreasing dung beetle species richness with decreasing overall mammal biomass and (3) decreasing dung beetle size with decreasing large mammal biomass. Moreover, our study demonstrated the importance of the composition of mammal communities in structuring dung beetle communities. This study documented how selective changes in mammalian biomass and composition affect dung beetle species communities, which in turn may have cascading consequences for the ecosystem. Since most of tropical ecosystems are facing dramatic changes in mammalian composition, it is urgent to evaluate the functional losses associated with such co-extinctions. © 2013 Elsevier Ltd.

Comparison of four trap types for ambrosia beetles (Coleoptera, Scolytidae) in Brazilian Eucalyptus stands

Eucalyptus spp. plantations represent >60% of the reforested area in Brazil. Although ambrosia beetle attacks on live trees were at first nonexistent, they have begun to appear with greater frequency. Monitoring for pest insects is a key factor in integrated pest management, and baited traps are one of the most widely used methods for insect population detection and survey. We compared the efficiency of the most widely used trap in Brazil to survey for ambrosia beetles and other Scolytidae, the ESALQ-84 type, with other traditionally employed traps: the multiple funnel (Lindgren trap); drainpipe; and slot (Theyson) traps, in a Eucalyptus grandis Hill ex Maiden stand in Brazil. The ESALQ-84 trap was the most efficient in trapping Hypothenemus eruditus Westwood and Hypothenemus obscurus (F.); the multiple funnel trap caught significantly more Cryptocarenus diadematus Eggers; whereas the slot trap caught more Premnobius cavipennis Eichhoff and Xyleborus affinis Eichhoff than the other traps. The drainpipe trap was the least effective trap overall. When corrected for number of beetles caught per trap surface area, catches were significantly higher on the ESALQ-84 trap for the majority of the species analyzed, probably because of a smaller trap surface area. The slot trap was recommended for it caught overall more beetles of the three most economically important scolytid species in eucalypt plantations in Brazil, P. cavipennis, X. affinis, and X, ferrugineus.

Ambrosia and bark beetles (Scolytidae : Coleoptera) in pine and eucalypt stands in southern Brazil

More than 95% of the reforested area in Brazil is covered by exotic Eucalyptus and Pinus plantations. Native Scolytidae, mostly ambrosia beetles, appear to be rapidly adapting to these exotic trees, and reports of economic damage are becoming frequent. The objectives of our research were to survey, characterize and compare the Scolytidae fauna present in a P. taeda and an E. grandis stand in Telemaco Borba, Parana state, Brazil. Beetles were caught in ethanol baited ESALQ-84 vane traps in weekly collections from July 1995 until July 1997. In all, 87 species were trapped, 62 in the pine and 75 in the eucalypt stand. The most abundant beetle species in the pines were Hypothenemus eruditus, Xyleborinus gracilis, Cryptocarenus sp. and Xylosandrus retusus, while the most frequent were H. eruditus, Cryptocarenus sp., H. obscurus, Ambrosiodmus obliquus, and X. gracilis. In the eucalypt stand, H. eruditus, X. retusus, H. obscurus, X. ferrugineus and Microcorthylus minimus were the most abundant species, and H. eruditus, H. obscurus and M. minimus were the most frequently trapped. The majority of the species, regardless of the forest community, were most active between August (end of winter) and October (mid-spring). Significantly more H. eruditus, X. gracilis, Cryptocarenus sp., Corthylus obliquus, Hypothenemus bolivianus, A. obliquus, Sampsonius dampfi and Xyleborus affinis were trapped in the pine stand, while X. retusus, H. obscurus, X. ferrugineus, Xyleborinus linearicollis, Corthylus sp, and Corthylus convexicauda were caught in higher numbers in the eucalypt stand. Approximately 50% of the species trapped were found in both communities. Morisita's similarity index indicates the composition of the two communities is very similar, suggesting that most of the beetles are polyphagous. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Water beetles in mountainous regions in southeastern Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

THE EXTENT of SEED PREDATION BY BRUCHINE BEETLES (COLEOPTERA: CHRYSOMELIDAE: BRUCHINAE) IN A HETEROGENEOUS LANDSCAPE IN SOUTHEASTERN BRAZIL

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Heterochromatin, Sex Chromosomes and rRNA Gene Clusters in Coprophanaeus Beetles (Coleoptera, Scarabaeidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytogenetic Mapping of rRNAs and Histone H3 Genes in 14 Species of Dichotomius ( Coleoptera, Scarabaeidae, Scarabaeinae) Beetles

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evolutionary dynamics of heterochromatin in the genome of Dichotomius beetles based on chromosomal analysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Developmental biology, polymorphism and ecological aspects of Stiretrus decemguttatus (Hemiptera, Pentatomidae), an important predator of cassidine beetles

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Attraction of ambrosia beetles (Coleoptera : Scolytidae) to different tropical pine species in Brazil

Ambrosia beetles are the predominant Scolytidae in Brazil. Little is known about the attractiveness of exotic conifer tree volatiles to native scolytids. Objectives were to compare the attractiveness of logs with and without bark of Pinus oocarpa Schiede, P. caribaea variety bahamensis Barrett & Golfari, P, car. variety caribaea Barrett & Golfari and P. car. variety hondurensis Barrett & Golfari over time to native scolytids in different pine stands, to compare the relative attractiveness of logs relative to ethanol traps, to determine how long it takes for logs to become attractive to ambrosia beetles and when attraction peaks occur, and to determine if volatiles released by live standing trees would mask volatiles released by logs of the same species. In young stands, Hypothenemus was the predominant insect genus, whereas in older stands Xyleborus predominated. Debarked logs trapped more beetles than logs with bark. Pine log species attractiveness was not influenced by volatiles present in the stand. Beetles were divided into the following 3 groups, based on response to log volatiles and ethanol: (1) species attracted to ethanol and not responding to pine terpenes Ambrosiodmus hagedorni (Iglesia), A. retusus (Eichhoff), X. spinulosus Blandford, Corthylus schaufussi Schiede, Cryptocarenus heveae (Hagedorn), H. obscurus (F.), (2) species attracted to ethanol but responding to pine terpenes Xyleborinus gracilis (Eichhoff), X. affinis Eichhoff, H. eruditus Westwood, Premnobius cavipennis Eichhoff, and (3) species more attracted to pine terpenes and less responsive to ethanol, A. obliquus (Le Conte), X. ferrugineus F,, X. catulus Blandford. Pinus car. ;variety bahamensis was the least attractive pine, P. oocarpa the most attractive. The attraction peak varied according to the season; logs were not attractive to beetles 10 wk after cutting.

Distribution of carabid beetles in agroecosystems across spatial scales - A review

The review focuses on the questions (1) how does the spatial heterogeneity of landscape influences carabid biodiversity, and (2) what are the main factors causing this biodiversity across nested spatial scales (study point - plant association - landscape level). The analysis of recent literature indicates that the spatial distribution of carabids differs at various spatial scales, and the factors responsible for the distribution are different. At the study point level most of the communities exhibit high variability of population density and diversity, which has no correlations with soil, and sometimes, vegetation, parameters. Most of the factors that contribute to formation of the communities are stochastic, simply because patches of a factor are much smaller than the size of a distinct carabid community. At the level of plant association, soil factors begin to play the role in driving the communities. At this level, litter depth, micro-climate and vegetation composition are the main factors. At the landscape level, geological factors, such as topography, landscape geochemistry, and history are playing important roles. As a conservation measure, spatial heterogeneity should be kept at all spatial scales at the same time to maintain carabid biodiversity in agricultural areas.

Analysis of the influence of pre-loading in the rating life calculation of tapered roller bearings applied to lightweight front-axle differentials

For intricate automotive systems that enclose several components, such as gearboxes, an important aspect of the design is defining the correct assembly parameters. A proper assembly can ensure optimized operating conditions and therefore the components can achieve a longer life. In the case of the support bearings applied to front-axle lightweight differentials, the assembly preload is a major aspect for an adequate performance of the system. During the design phase it is imperative to define reference values to this preload, so the application would endure its requirements. However, with the assistance of computer simulations, it is possible to determine an optimum condition of operation, i.e. optimum pre-load, which would increase the system reliability. This paper presents a study on the influence of preload on the rating life of tapered roller bearings applied to light-weight front axle differentials, evaluating how preload affects several key parameters such as rating life and displacement of components, taking into account the flexibility of the surrounding differential housing. Copyright © 2012 SAE International.