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The ant genus Linepithema is widely known, thanks to the pest species Linepithema humile (Mayr), which is easily mistaken for Linepithema micans (Forel) due to their morphological similarity. Like L. humile, L. micans is associated to the main grapevine pest in Brazil, Eurhizococcus brasiliensis (Wille), also known as ground pearl. Therefore, the present study uses mtDNA fragments to expand the knowledge of haplotype diversity and distribution of L. micans in the state of Rio Grande do Sul (Brazil), to understand the genetic differences of the populations identified in this study. We identified 15 haplotypes of L. micans spread across different localities. Twelve of these haplotypes were new for the species. The high haplotype diversity uncovered in Rio Grande do Sul (Brazil) for this species was predictable, as L. micans is in its native environment. Additional studies that take gene flow into account may reveal interesting aspects of diversity in these populations.

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In many sugarcane plantations in Brazil, the straw is left on the soil after harvesting, and vinasse, a by-product of the production of sugar and ethanol, is used for fertigation. Our goal was to compare ant community composition and species richness in the straw mulch of sugarcane crops with the leaf litter of neighboring forests. We tested the hypothesis that ant communities in the straw mulch of vinasse-irrigated sugarcane crops and in the forest leaf litter were similar, because the combination of straw mulching and vinasse irrigation has a positive effect on soil fauna. Straw mulch and leaf litter were collected from 21 sites and placed in Berlese funnels. In total, 61 species were found in the forest leaf litter, whereas 34 and 28 species were found in the straw mulch of sugarcane fields with and without vinasse, respectively. Ant communities differed between forest and crop fields, but the species in the sugarcane straw mulch were a subset of the species found in the forest leaf litter. Although vinasse is rich in organic matter, it did not increase ant diversity. Seven feeding and/or foraging types were identified and, among the different types, surface-foraging omnivorous ants were the most prevalent in all habitats. Vinasse-irrigated sugarcane straw mulch had more predatory species than mulch from vinasse-free fields, but fewer than forest leaf litter. However, this positive effect of vinasse irrigation should be carefully evaluated because vinasse has negative effects on the environment.

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Sugarcane is an important crop within the Brazilian socioeconomic landscape. There is a constant need for approaches to increase sustainability at all steps of the production chain. Irrigating sugarcane crops with vinasse is one of these approaches, because vinasse is a residue of sugarcane processing that can be used to fertilize these same crops. However, due to its chemical properties, vinasse may be harmful to soil fauna. Analyzing the structure and functional organization of ant communities is a fast and practical way to monitor sites affected by the addition of chemicals. This study compared the structure of soil ant communities in vinasse-irrigated sugarcane crops to those in secondary forests adjacent to the crops. In total, 32 genera and 107 species of ants were observed; of these, 30 species foraged in crop fields and 102 foraged in forests. Twenty-five percent of the species were present in both crops and forests. Ant communities in crop soil had poorer taxonomic composition and lower richness in each functional group compared to communities in forest remnants. However, regardless of vegetation type, epigeic ants were more diverse, and Dorymyrmex brunneus (crop) and Pachycondyla striata (forest) were very frequent. Vinasse did not increase the diversity of epigeic and hypogeic ants, but it may affect the community composition.

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Camponotus textor Forel is, to date, the only weaver ant recorded from Brazil, and all existing studies on the species are restricted to describing its weaving and nesting behaviors. The aim of this work is to establish the molecular profile of the species. We sampled eight different colonies by sequencing mitochondrial genes (COI, transfer DNA (tRNA), and an intergenic spacer) and the nuclear gene 28S ribosomal DNA (rDNA). We then assessed haplotype diversity and also analyzed distribution patterns of this species based on the correlation between genetic and geographic distances. Our results provide an additional tool for species identification by identifying new regions that can be used as molecular markers for barcoding (such as the intergenic spacer (IGS) and tRNA-Leu). In addition, the phylogenetic analysis revealed that C. textor has features that could be associated with deep population divergences. We identified a wide range of mitotypes and three distinct groups, suggesting a possible reduction of gene flow between colonies.

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Linepithema micans (Forel) is considered to be the main ant species responsible for the spread of Eurhizococcus brasiliensis (Wille), a soil scale that damages vine plants in southern Brazil. In this work, the seasonal life cycle of L. micans was evaluated in vineyards to define the most appropriate time for the application of toxic baits for control. Ant nests were transported to the laboratory in plastic bags, and individual ants were separated into groups of eggs, larvae, pupae, workers, males, and queens, recording the number of individuals per colony. The seasonal life cycle of L. micans in the vineyards began in spring with the deposition of eggs by queens. During the warm months of the year (spring and summer), it was possible to observe nests consisting primarily of eggs and pupae. During the autumn and winter months, the colonies were composed predominantly of larvae and a reduction in eggs was observed. Because the main control strategy targets the larval stage of the insect, the application of toxic baits for the control of L. micans must be performed during the winter.

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Linepithema micans (Forel) (Hymenoptera: Formicidae) is reported to occur from eastern Brazil to central Argentina in pasture or grassland, forest and second growth riparian forest, nesting under stones, rotting wood, and sandy soil. However, information on this species is poor and its ecological interactions and role as pests are unknown. Linepithema humile (Mayr), a closely related species to L. micans, known as the Argentine ant, is native to South America, and was accidentally introduced to several regions of the world. Recent studies have shown that other related species, such as L. micans, could become as pestiferous as L. humile because of its phylogenetic proximity. Samples of L. micans from different habitats in Southern Brazil were characterized by sequencing of the mitochondrial DNA. Sequences were compared to previously obtained sequences from samples of L. humile and the genetic distance and differences in the tRNALeu structure were investigated. Our data identified three haplotypes of L. micans, two of which were observed in ant populations closely associated with the Brazilian ground pearl Eurhizococcus brasiliensis (Hempel) (Hemiptera: Margarodidae), a soil scale that is a serious pest of vineyards. The third haplotype was identified in ants from populations invading residences in urban habitats.

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The Asian subterranean termite, Coptotermes gestroi, originally from northeast India through Burma, Thailand, Malaysia, and the Indonesian archipelago, is a major termite pest introduced in several countries around the world, including Brazil. We sequenced the mitochondrial COII gene from individuals representing 23 populations. Phylogenetic analysis of COII gene sequences from this and other studies resulted in two main groups: (1) populations of Cleveland (USA) and four populations of Malaysia and (2) populations of Brazil, four populations of Malaysia, and one population from each of Thailand, Puerto Rico, and Key West (USA). Three new localities are reported here, considerably enlarging the distribution of C. gestroi in Brazil: Campo Grande (state of Mato Grosso do Sul), Itajaí (state of Santa Catarina), and Porto Alegre (state of Rio Grande do Sul).

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The presence of bees (Apis mellifera L.) in urban areas has increased in recent years due to environmental disturbances caused by humans. Bee migration to cities may provoke serious accidents, since some people present allergic reactions to their venoms. In Rio Claro city, São Paulo state, Brazil, the number of calls to the fire brigade for removal of bee swarms, and the number admissions in local hospitals due to bee stings were investigated during 2002 and 2003, and a correlation between these data and the average temperature, rainfall and relative humidity was found. The study period was divided into three phases according to the number of times that the fire brigade was called to remove swarms (263 times): January to July 2002 - 51 calls (19.39 percent); August 2002 to July 2003 - 140 calls (53.23 percent); and August to December 2003 - 72 calls (27.38 percent). A significant correlation among the number of calls, the local temperature and rainfall was detected. The number of accidents was not associated with environmental variables. Based on the current results, public activities for prevention of bee attacks may be developed to avoid unwanted contact between humans and these insects, and/or provide the appropriate management of the colonies.

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The presence of bees (Apis mellifera L.) in urban areas has increased in recent years due to environmental disturbances caused by humans. Bee migration to cities may provoke serious accidents, since some people present allergic reactions to their venoms. In Rio Claro city, São Paulo state, Brazil, the number of calls to the fire brigade for removal of bee swarms, and the number admissions in local hospitals due to bee stings were investigated during 2002 and 2003, and a correlation between these data and the average temperature, rainfall and relative humidity was found. The study period was divided into three phases according to the number of times that the fire brigade was called to remove swarms (263 times): January to July 2002 51 calls (19.39%); August 2002 to July 2003 140 calls (53.23%); and August to December 2003 72 calls (27.38%). A significant correlation among the number of calls, the local temperature and rainfall was detected. The number of accidents was not associated with environmental variables. Based on the current results, public activities for prevention of bee attacks may be developed to avoid unwanted contact between humans and these insects, and/or provide the appropriate management of the colonies.(AU)

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ABSTRACT For an adequate management program of urban ants, knowledge on their biology is required, with the aim of detecting and exploring their vulnerabilities. This type of information has been used in the manufacture of baits, which must show, among other characteristics, attractiveness to several species to be considered efficient and economically viable. Therefore, the present study was aimed to evaluate in the laboratory the attractiveness of sweet and fatty substances to Camponotus vittatus, trying to find which substances would be more efficient to be introduced as the attractive component in baits. Five colonies, 68 sweet substances and 23 fatty substances were utilized in the laboratory trials. The most attractive sweet and fatty substances, were, respectively, 75% demerara sugar and vegetable fat. When substances of both natures were tested together, sweet substances presented slightly higher attractive indexes than oily substances.

RESUMO O manejo adequado das formigas urbanas exige conhecimentos sobre a biologia, com a finalidade de detectar e explorar vulnerabilidades. Essas informações vêm sendo utilizadas no desenvolvimento de iscas que, para serem eficazes e economicamente viáveis, entre outras características, devem ser atrativas para várias espécies de formigas. No presente estudo avaliouse em laboratório a atratividade alimentar de substâncias açucaradas e gordurosas para a espécie Camponotus vittatus, averiguando quais seriam os componentes mais adequados a serem introduzidos na composição da isca. Os testes foram realizados em cinco colônias, sendo avaliadas 68 substâncias açucaradas e 23 gordurosas. As mais atrativas foram o açúcar demerara 75% e a gordura vegetal. Quando ambas as substâncias foram testadas em conjunto, as açucaradas tiveram uma atratividade ligeiramente superior às gordurosas.