Suchergebnisse

A new species of Chartergellus­, collected in Acre, Northern Region of Brazil, is described and comparative remarks are given.

This work aims to recognize and record the occurrence of species of social wasps (Polistinae) in organic tobacco crops, as well as to point out possible species that may be used in future biological control programs. The research was conducted in Virginia-type tobacco farming with organic management in two regions in south of Brazil. The collections were carried out with Malaise trap, during the harvests 2008/2009, 2009/2010 and 2010/2011. A total of 2.738 wasps, from which 23 species distributed in six genera was collected. Polistes was the most diverse genus (8 species), followed by Polybia, Mischocyttarus, Agelaia, Bachygastra and Protonectarina. Polybia scutellaris was the most abundant species, being considered eudominant. Agelaia multipicta and Polybia sericea with are also among the most abundant. This information is relevant for the insertion of social wasps with potential agents in the biological control of tobacco pests.

Social wasps are common elements in Neotropics, although even elementary data about this taxon in the Amazon region is partially unknown. Therefore the purpose of this work was to increase the knowledge of social wasp fauna at the Ducke Reserve. One hundred and three species belonging to nineteen genera were recorded. The richest genera were Polybia (28 species), Agelaia (12) and Mischocyttarus (12). Seventy species was collected in active search, 42 species using Malaise trap, 25 suspended trap, 20 attractive trap and nine light trap. Ducke Reserve has one of the highest number of Polistinae wasps in reserves or parks in the Neotropic region.

Tocantins state has high biodiversity and a high degree of endemism, nevertheless, there are no studies on the diversity of social wasps. This study introduces a survey of social wasps actively collected using entomological nets and Malaise trap in addition to different light traps in sixteen sites in the Amazon and Cerrado biomes in Tocantins state, Brazil. We sampled a total of 1,013 social wasps distributed in 57 species of 13 genera. Fifty of these species and nine genera represent new distribution records for the state. Some species are not commonly found in collections and lists of species, and Protopolybia picteti (de Saussure, 1854) is newly recorded for Brazil. Such an increase of 714% may indicate that Polistinae richness is probably higher in the studied regions and that the state of Tocantins may well contain several additional (yet unrecorded) social wasp species. More comprehensive studies should be conducted to enhance the knowledge of wasp species in this state, contributing to our understanding of the biodiversity in Northern Brazil.

The Roraima state in Brazil is part of Northern Amazon, an area harboring high biodiversity and high degree of endemism. Nevertheless, there are few studies on diversity of social wasps occurring in this region. This study presents a list of social wasps (Vespidae: Polistinae) collected actively and using Malaise, Suspended and Light trap in six localities in Roraima state. A total of 85 species of 14 genera were collected. Fourty-five of these species are new distribution records to Roraima state, some species are not common found in the collections and lists of species, and some are recorded for the second time to Brazil or the Amazon region. This increase may be an indication that the Polistinae richness is probably higher in the regions studied and that Roraima may well contain a number of additional (as yet unrecorded) social wasp species. More comprehensive studies are needed in order to increase the knowledge of wasp species in Roraima, contributing to increased knowledge of the diversity in Northern Brazil.

Basic research assessing environmental effects on entire pollinator communities are still uncommon, particularly for rare and commercially unattractive plant-pollinator partners. We investigated the community of flower visitors of Erythroxylum myrsinites to check for potential pollinators and to check the extent of weather influence of visitor behaviour, registered as the number of visitors attending flowers of E. myrsinites. We then calculated species' dominance and constancy and assessed location of pollen attachment in each visitor's body. We correlated weather variables with the composition and abundance of visits carried out by the entire community and by most constant and dominant species. The wasps Polybia sericea, P. ignobilis and P. fastidiosuscula showed the highest values of constancy, dominance and attached pollen. There was a community-level effect of atmospheric pressure, solar radiation and wind speed on the number of visits. Atmospheric pressure affected the number of visits of eudominant species P. fastidiosuscula and P. sericea, while solar radiation affected the number of visits of P. ignobilis. Our results demonstrate the influence of weather variables on flower visiting insects and suggest the importance of native wasps in pollen transport and pollination, a relationship that should be further studied under the worldwide bee pollination decline.

This work recorded 593 specimens allocated in 11 genera and 23 species of social wasps were collected in Ubajara National Park and Sete Cidades National Park, Caatinga Biome, Northeast of Brazil. Chartergellus communis Richards, 1978, Chartergus globiventris de Saussure, 1854, Metapolybia docilis Richards, 1975, Polybia paulista (von Ihering, 1896), P. rejecta (Fabricius, 1798), Protonectarina sylveirae (de Saussure, 1854) and Protopolybia exigua (de Saussure, 1854) are new occurrence records for Ceará state. Apoica flavissima van der Vecht, 1898, Brachygastra augusti (de Saussure, 1854), C. globiventris, Metapolybia cingulata (Fabricius, 1804), Polybia chrysothorax (Lichtenstein, 1796), P. paulista, P. scutellaris (White, 1841) and Protopolybia chartergoides Gribodo, 1891 are new occurrence records for Piauí state. Eighteen species were collected in the Ubajara National Park, being eight exclusive and fifthteen in the Sete Cidades National Park, being five exclusive; ten species were collected in both Parks. Brachygastra augusti and M.docilis are new records for Caatinga biome.

Wasps of the genus Polistes (Vespidae: Polistinae) are eusocial, considered valuable biological control agents. The objective of this work was to determine the resources collected by Polistes canadensis wasps, evaluate their performance and importance as a natural enemy and possible agent of biological control in the Brazilian Amazon. Between 8 October and 20 November of 2014, 20 evaluations were performed, totalizing 101 hours of observations of the foraging activity of an aggregation out in stage of development post-emergence with approximately 50 adult individuals distributed in 15 colonies. Additionally, observations of the predatory activity of Polistes canadensis on Plutella xylostella on a small organic plantation of kale (Brassica oleracea L. var. acephala DC), were also made. During the evaluations 1742 returns were recorded, 11.72% of them with prey, 3.10% with plant fiber, 16.76% with nectar, 45.17% with water and 23.25% without any visible load. All the preys identified were classified as Lepidoptera, belonging to ten morphospecies. Only one morphospecies was identified as Spodoptera frugiperda, which was the most commonly resource used by the wasps in 37 % in immature feeding. Only returns with nectar had statistically significant difference between the evaluated schedules. Polistes canadensis wasps did not prey Plutella xylostella caterpillars. The wasp aggregation studied was able to prey an average of 10.2 caterpillars per day, which demonstrates the potential of this species for the biological control of pests in the Amazon region.

Most studies about the insect community in rainforests only focus on the forest understory, and even though the rainforest canopy is one of the most fascinating and diverse environments, it remains poorly explored. Therefore, we analyzed the difference between the social wasp composition in these two strata at the ZF-2 Station in the Brazilian Amazon Rainforest, using flight interception traps (Malaise model Gressi and Gressi), in the rainforest understory and canopy. We collected ninety-two species belonging to 18 genera; Polybia was the richest genera (22 species), followed by Mischocyttarus (14) and Agelaia (13). Forty-four species were exclusively collected in the understory, twenty exclusively collected in the canopy, and twenty-eight in both strata. The understory was distinctly more diverse and more abundant than the canopy, while some rare or poorly collected species were only found in the canopy. We found a strong relationship between the species composition at the ZF-2 Station and the Ducke Reserve. Therefore, we suggest using traps in canopy in the Amazon biome as an effective method for collecting a higher diversity of social wasps.

The thematic network 'Biodiversity of Insects in the Amazon' is the first network among researchers of the Brazilian Amazon in terms of the increase of knowledge and provision of subsidies for the conservation of Amazonian biodiversity, focusing on insects, and disseminate this knowledge to different sectors of society. In this way, expeditions to six localities in the Amazonas State were carried out and we present here the results for social wasps (Vespidae: Polistinae). We used two modified Malaise traps combined with two suspended traps from July 2016 to June 2017. A total of 140 species and 20 genera were collected: 92 species and 18 genera in ZF-2-Manaus area, where the greatest diversity was recorded, followed by Tefé (73 species, 16 genera), Careiro-Castanho (72 species, 17 genera), Novo Airão (71 species, 16 genera), Presidente Figueiredo (62 species, 16 genera), and Ipixuna (58 species, 17 genera). Metapolybia rufata Richards, 1978 and Polybia diguetana du Buysson, 1905 were new records for Brazil, and other six species were first records for Amazonas state. The results indicate that further investigations should significantly increase the species diversity of wasps in the Amazon region and add more information to the knowledge of Polistinae diversity.

Diaphania hyalinata (Lepidoptera: Crambidae), popularly known as "melonworm moth", is considered a main pest of the cucumber, and depending on the intensity of infestation, the damage can reach 100%. Herein, we report the predation of D. hyalinata larvae by seven social wasp species: Brachygastra lecheguana, Polybia dimidiata, Polybia ignobilis, Polybia liliacea, Protopolybia minutissima, Synoeca surinama and Synoeca virginea, and predation of D. hyalinata pupae by Polybia liliacea. We suggest that Polybia liliacea, should be considered as a potential biological control for cucumbers, due to its high index of captured prey and intense foraging activity.

Diversity of wasps (Hymenoptera: Vespidae) in conventional and organic guarana (Paullinia cupana var. sorbilis) crops in the Brazilian Amazon. The present study aimed to determine the diversity of wasp species associated with the guaraná crop and the difference in composition of species associated to organic and conventional crops, as well as among environments established in each management (adjacent forest, crop edge and guaraná crop). We collected 977 individuals and 59 species, in 23 genera of Vespidae, sixteen of Polistinae (52 species) and seven Eumeninae (seven species). Polybia was the most abundant and rich genus with 553 specimens and 15 species, followed by Agelaia (139, nine) and Protopolybia (103, five). In organic management crop, 686 individuals allocated in 18 genera and 47 species were collected, whereas in conventional management crop 291 individuals allocated in 18 genera and 41 species were collected. According to the three sampling points, in both management types, the edge of the crop field shows the highest abundance of wasps with a total of 519 individuals allocated in 19 genera and 45 species. Given the intense use of both environments (forest and crop) by the wasps, it is important to grow crops in regions near native forests, where the chances of social wasp colonies to be founded are increased.

We studied the seasonality and made notes about the nesting habits of the endemic social wasp Polistes ridleyi Kirby, 1890 of the Fernando de Noronha Archipelago. We collected 427 adult paper wasp P. ridleyi specimens for nine months using Malaise interception traps. The highest abundance of wasps was observed in October, November, and December, a fact most likely explained by the lowest precipitation levels on the island. We recorded 38 P. ridleyi nests. However, most of them were collected in a single Cynophalla flexuosa (L.) plant. This agglomeration may suggest multi-combs behavior, as reported for another species of Polistes spp.

Parachartergus wasps are known by having a very aggressive behavior, especially the large black species with white wings tip, which have painful stings. They exhibit a unique and interesting characteristic, the capacity to venom spraying during the colony defense or self-defense. However, for the Amazonian species Parachartergus fulgidipennis (de Saussure, 1854), little is known about its behavior and nesting. In this way, we tracked and described the nesting site, the numbers of combs, and performed an ad libitum method to record behavioral activities. The nest was fixed vertically on a man-made concrete column, 1.2 m above the ground, measuring 25.0 x 6.0 cm and contained four combs with approximately 74 cells, with 31 eggs, seven larvae, 30 pupae, and almost 42 adults. With a flat thin grayish envelope with weak corrugations, the nest is very similar to the color of the substrate which turn in to really cryptic. The colony defense behavior presented by this species is unaggressive and very docile, suggesting that is not similar as observed for other Parachartergus species.

Hymenotpera species may act as necrophagous, consuming decomposing tissues, as predators, when they feed on other immature and adult insects, and parasites of larvae and pupae of dipterans and coleopterans that colonize the carcasses. In this way, the fauna of four Hymenoptera families (Vespidae, Apidae, Icheneumonidae and Formicidae) associated to different decomposition stages of Sus scrofa carcass partially submerged in igarapé of the "terra-firme" Amazonian forest are presented. Formicidae were the most abundant insects with 957 individuals collected all directly in the carcass, followed by Vespidae (143), Apidae (88) and Ichneumonidae with nine individuals collected in the suspended trap. Due to the aspect of the injuries caused by some Hymenoptera to the carcass, they may be mistaken as skin ulcers, burns or abrasions, which may mislead a forensic investigation.