An improved bait method for collecting Hymenoptera, especially social wasps (Vespidae: Polistinae)

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

Predaceous ant fauna in new sugarcane fields in the state of São Paulo, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Angling sport fishing in Lobo-Broa reservoir (Itirapina, SP, Brazil)

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

Attractiveness of copperleaf-based bait to leaf-cutting ants

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

DISTRIBUIÇÃO DE SUBSTRATOS NAS COLÔNIAS DE Atta laevigata (F. Smith, 1858) (HYMENOPTERA: FORMICIDAE)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Field methods for the study of ants in sugarcane plantations in Southeastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Variability of non-mutualistic filamentous fungi associated with Atta sexdens rubropilosa nests

A survey of the filamentous fungi other than the symbiotic one found in association with Atta sexdens rubropilosa colonies was carried out. Different fungal species (27 taxa) were isolated a few days after treating the workers with toxic baits (sulfluramid; Mirex-SO), from 40 laboratory and 20 field nests. Syncephalastrum racemosum (54 %) and Escovopsis weberi (21 %), Trichoderma harzianum (38 %) and Fusarium oxysporum (23 %) were the prevalent species in laboratory and field nests, respectively. Acremonium kiliense, Acremonium strictum, E. weberi, F oxisporum, Fusarium solani, Moniliella silaveolens and T harzianum were found in both nests' groups. We revealed that many filamentous fungi can co-exist in a dormant state inside the nests of these insects and some of them appear to be tightly associated with this environment.

FIRE ANT MOUND DENSITIES IN THE UNITED-STATES AND BRAZIL (HYMENOPTERA, FORMICIDAE)

To compare fire ant populations (Solenopsis) in North and South America, we surveyed 102 preselected roadside sites, half in the southeastern United States and half in the state of Mato Grosso do Sul, Brazil. Fire ants were considerably more abundant in the United States. They occurred at more sites (100 versus 70%), in higher densities (170 versus 30 mounds/ha), in larger mounds (27.0 versus 13.8 liters), and they constituted a larger fraction of the local ant community (97 versus 13% of occupied baits). These data are consistent with the hypothesis that North American populations of S. invicta have escaped natural biological control; however, cultural and climatic factors are also likely explanations.

Preferência alimentar da formiga urbana Camponotus vittatus forel (Hymenoptera: Formicidae)

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.

Mirmecofauna em um fragmento de floresta atlântica urbana no município de Marília, Brasil

The aim of this study was to verify the influence of the habitat fragmentation on the Ant Fauna in an urban fragment of Semideciduous Seasonal Atlantic Forest located in the municipality of Marilia, São Paulo, Brazil. The studied fragment was divided into three environments in relation to edge: "Edge" (2m), "Transition" (30m) and "Interior" (90m). By using pitfalls traps and attractive baits there were done nine samples between November 2007 and February 2008. There were collected 3.873 individuals distributed into five subfamilies, 19 genera and 33 species. Five species were abundant on three studied environments: Ectatomma sp1, Mycocepurus goeldii, Paratrechina sp1, Pheidole sp2, Trachymyrmex sp1, Wasmannia auropunctata. The edge and transition environments presented the lower Simpsons diversity index and higher species dominance. However, it was observed little variation between these parameters between environments. Faunistic similarity between environments, expressed by Jaccard's similarity index showed high similarity between all studied environments. Because the studied site is an urban fragment, the similarity found between these areas can be related to habitat fragmentation process, an historical of constant anthropic perturbation and low local colonization rates. However, we suggest that a posteriori evaluation should be done with other arthropods groups like spiders and beetles in due to understand the changes that occur in urban fragments and support the choice of conservation and management actions in favor of this important forest remnant localized in urban area of Marilia, São Paulo, Brazil.

Trajectory of Water- and Fat-Soluble Dyes in the Grass-Cutting ant Atta capiguara (Hymenoptera, Formicidae): Evaluation of Infrabuccal Cavity, Post-Pharyngeal Glands and Gaster

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resource partitioning among epigaeic and hypogaeic ants (Hymenoptera: Formicidae) of a Brazilian cocoa plantation

Patterns of dietary and foraging strata utilization by the ground ant community of a Brazilian cocoa planatation were examined using sugar, meat and flour baits on the surface as well as buried. A total of 49 ant species was recorded, including 10 species of Pheidole. Strong dominance was exercised by Solenopsis geminata at both surface and subterranean strata, and at all food resources. The dissimilarity matrix of the epigaeic ant fauna was much greater than that for the hypogaeic species. At least four guilds were identified: the fungus-growing ants, epigaeic nectivores, epigaeic carnivores, and hypogaeic foragers. Niche breadth reduction, leading to the formation of guilds, permits the coexistence of many species in the this ground ant community from a tropical cocoa plantation. -Authors

Foraging, diet and community structure in an epigaeic ant (Hymenoptera: Formicidae) assemblage: the role of recruitment

The significance of recruitment systems for community structure of epigaeic ants in a tropical upland forest in southern Brazil was evaluated by examining patterns of spatial occurrence at fixed points. Normal exploratory activity was evaluated with pitfall traps, while the effect of recruitment and diet was evaluated by using honey and sardine baits at the same points. Through techniques developed for environmental impact assessment, the significance of recruitment was evaluated following perturbation, or the placement of bait. Of the 46 species encountered, 15 were sufficiently frequent to study. Of these, only 6 showed significant spatial frequency changes at baits when compared with pitfall trap collections. In one analysis, monthly differences were important for a few smaller species, suggesting thermic limitations, while bait types either increased or decreased spatial point usage. The magnitude of spatial point variation is an index for the strength of recruitment in community organization. Bait types suggest nutritional possibilities of each species. Both recruitment and diet are probably functions of the species composition of the ant community.

Hypogaeic anti epigaeic ant (Hymenoptera: Formicidae) assemblages of atlantic costal rainforest and dry mature and secondary amazon forest in Brazil: Continuums or communities

Meat, flour and sugar baits were used on the soil surface and buried to examine species composition of the ant fauna in three separate tropical forests in Brazil, and to control for the effect of the regional faunal pool. Compositional mosaic diversities were comparable among areas, bait types and foraging strata. Mosaic diversity was independent of mean assemblage size. The number of unique species per sampling unit was correlated with mean assemblage size. Canonical correspondence analysis ordered species first by foraging substrate, second by geographic location, and third by diet. The first axis was significantly correlated with mean similarity and affinity. Mean Mahanalobis distances between centroids of groups based upon foraging strata were significantly larger than between localities, indicating local ecological pressures stronger than regional species pool constraints. As most. species foraged in only one stratum in one geographical position and were not omnivorous, the response of species to environmental gradients (continuums) showed a lower coherency with these patterns than did communities, structured around guilds based upon foraging strata and diet.

Method for the evaluation of insecticidal activity over time in Atta sexdens rubropilosa workers (Hymenoptera: Formicidae)

The active ingredients used in the formulation of toxic baits for leaf-cutting ants (Hymenoptera: Formicidae) should possess a delayed action defined as an insecticidal activity whereby worker mortality is ≤15% at 24 hours and ≥90% at 21 days. Serious shortcomings have occurred in the search for new active ingredients, such as the initial selection of fenoxycarb, copper oxychloride and diflubenzuron, compounds considered very promising but whose inefficiency was verified only later, indicating methodological problems. In view of this situation, we developed a classification method for insecticidal activity over time using workers of the leaf-cutting ant Atta sexdens rubropilosa Forel. The insecticides used were fipronil, sulfluramid GX071HB and sulfluramid GX439, vehicled in an attractive pasty formulation prepared based on citrus pulp. The results obtained were consistent from a toxicological viewpoint and agreed with the literature in terms of the control of colonies. Sulfluramids were found to possess a delayed action at a broad range of concentrations, in agreement with the fact that these substances are highly effective in the control of all leaf-cutting ant species. The smaller range of concentrations of fipronil with delayed action is probably related to its lower efficacy for species more difficult to control such as Atta capiguara (Forti et al. 2003). We discuss the importance of relating behavioral particularities to the specific feeding habits of leaf-cutting ants, with methodological adequacy of the assessment of insecticides aimed at toxic baits.