Ant fauna (Hymenoptera: Formicidae) in Magnoliophyta native to the Atlantic forest

The aim of the study was to analyze the preferences of ant species visiting the trunks of eight species of Magnoliophyta, belonging to the families Fabaceae, Arecaceae, Myrtaceae, Melastomataceae and Euphorbiaceae, located in a fragment of the Atlantic Forest in southeastern Brazil. A total of 101 ant species, belonging to eight subfamilies and 32 genera, were sampled during the 12-month collection period. Close to 30% of the ant species can be considered arboreal, and the others are species that nest in the ground and use trees only for foraging, which can be occasional, as in the case of the Ecitoninae sampled in Arecaceae and Euphorbiaceae. Pachycondyla mesonotalis was the only species collected on all the Magnoliophyta, whereas Camponotus rufipes, Acromyrmex niger and Crematogaster spp., were found on 87.5% of the trees analyzed. No strong similarities were found, using the Jaccard Index, among plant species in the same family of Magnoliophyta based on the visiting ants, except for the Euphorbiaceae species. This result is probably related to the presence of extra-floral nectar, which is very attractive to ants and characteristic of this family.

Composition of the Ant Fauna (Hymenoptera: Formicidae) in Public Squares in Southern Brazil

The composition of the ant fauna was examined in public squares of three municipalities that compose the hydrographic basin of the Upper Tiete River: Biritiba Mirim, Salesopolis, and Mogi das Cruzes. Richness, frequency of occurrence, similarity, and influence of seasons on the species composition were examined. The method was standardized as sampling units consisted of a set of three baits arranged in a triangle with vertices two meters apart. Sardines in oil were used as attractant. A total of 86 species was collected. Myrmicinae and Pheidole were the richest subfamily and genus, respectively. Eighty species were collected in Mogi das Cruzes, 49 in Salesopolis, and 45 in Biritiba Mirim, with 34 species common to the three areas. The ordination analysis (NMDS) revealed the presence of two distinct communities: one in Mogi das Cruzes and another in Biritiba Mirim-Salesopolis. These data were supported by the dendogram based on the Bray-Curtis dissimilarity index. This result might be associated with the distinct geographic and demographic characteristics of the areas. Regarding seasonality, the composition of the fauna of Mogi das Cruzes is independent of the season of the year, unlike the observed in Biritiba Mirim and Salesopolis.

Spatial-Temporal Variation in Orchid Bee Communities (Hymenoptera: Apidae) in Remnants of Arboreal Caatinga in the Chapada Diamantina Region, State of Bahia, Brazil

The spatial and temporal distribution of organisms is a fundamental aspect of biological communities. The present study focused on three remnants of arboreal Caatinga in northeastern Brazil between May, 2009 and April, 2010. A total of 627 euglossine males were captured in traps baited with artificial aromatic compounds. The specimens belonged to 14 species and four genera: Euglossa Latreille, Eulaema Lepeletier, Eufriesea Cockerell, and Exaerete Hoffmannsegg. Eulaema nigrita Lepeletier (41.6), Euglossa carolina Nem,sio (15.3%), Eulaema marcii Nem,sio (13.6%), and Euglossa melanotricha Moure (12.8%) were the most common species sampled. The distribution of collected specimens per fragment was as follows: BraA(0)na (280 ha)-259 individuals belonging to 14 species; Cambui (179 ha)-161 individuals from eight species; and Pindoba (100 ha)-207 individuals represented by seven species. BraA(0)na had the highest diversity (H'aEuro parts per thousand= 1.91) and estimated species richness. The largest fragment was the main source of the observed variation in species richness and abundance, indicating a non-random pattern of spatial distribution. The analysis of environmental factors indicated that seasonal variation in these factors was the principal determinant of species occurrence and abundance.

Assembly of Myrmelachista Roger (Formicidae: Formicinae) in twigs fallen on the leaf litter of Brazilian Atlantic Forest

The nests of Myrmelachista are found in tree trunk cavities and branches. The biology of these arboreal ants is still relatively unknown. We investigated the nesting behaviour of this genus in fallen dry twigs in the Atlantic rainforest of southeastern Brazil. Physical characteristics of the nests, colony demographics, presence of breeders and ant worker sizes were recorded. Samples were collected weekly for 12 months, along open, sunny and undisturbed trails within forest remnants. In all, 202 nests were collected and six species were recorded. Myrmelachista ruszkii had the highest population of immatures and the greatest number of nests found. Myrmelachista nodigera had the smallest workers, was the least populous and the colony was housed in the finest branches. These results expand the current knowledge about the diversity and biology of Myrmelachista in the Brazilian Atlantic forest, and describe polydomic nests and competitive behaviour of M. ruszkii.

Habitat Fragmentation Effects on the Orchid Bee Communities in Remnant Forests of Southeastern Brazil

The effect of habitat fragmentation on the structure of orchid bee communities was analyzed by the investigation of the existence of a spatial structure in the richness and abundance of Euglossini species and by determining the relationship between these data and environmental factors. The surveys were carried out in four different forest fragments and one university campus. Richness, abundance, and diversity of species were analyzed in relation to abiotic (size of the area, extent of the perimeter, perimeter/area ratio, and shape index) and biotic characteristics (vegetation index of the fragment and of the matrix of each of the locations studied). We observed a highly significant positive correlation between the diversity index and the vegetation index of the fragment, landscape and shape index. Our analysis demonstrated that the observed variation could be explained mainly by the vegetation index and the size of the fragment. Variations in relative abundance showed a tendency toward an aggregated spatial distribution between the fragments studied, as well as between the sampling stations within the same habitat, demonstrating the existence of a spatial structure on a small scale in the populations of Euglossini. This distribution will determine the composition of species that coexist in the area after fragmentation. These data help in understanding the differences and similarities in the structure of communities of Euglossini resulting from forest fragmentation.

Composição da fauna de formigas (Hymenoptera: Formicidae) de serapilheira em florestas semidecídua e de Eucalyptus spp., na região sudeste do Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fauna de formigas (Hymenoptera: Formicidae) atraídas a armadilhas subterrâneas em áreas de Mata Atlântica

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Estudo da fauna de Euglossini (Hymenoptera, Apidae) em paisagem fragmentada na Serra da Forquilha, Jacutinga, região sul de Minas Gerais: diversidade de espécies e uso de habitats

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Fauna de Ichneumonidae (Hymenoptera: Ichneumonoidea) em um agroecossistema cafeeiro no Estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Vespas sociais da Floresta Nacional de Caxiuanã, Melgaço, Pará: descrição da fauna numa grade de 25 Km² e compararação entre protocolos de amostragem (Hymenoptera, vespidae)

Vespas sociais destacam-se pela complexidade da organização social, pela arquitetura dos ninhos e pela importância na cadeia alimentar, como predadores de outros insetos e artrópodes. Os levantamentos faunísticos no Brasil ainda são considerados reduzidos e há carência de padronização entre protocolos de coleta, o que dificulta a comparação dos resultados obtidos. O presente trabalho consiste em estudo da fauna de vespas sociais numa parcela de floresta de terra firme em Caxiuanã, Melgaço, PA, um quadrado de 25 km² previamente demarcado com trilhas de 5000 m entrecruzadas, em formato de grade. A coleta consistiu na busca ativa por indivíduos e colônias de vespas sociais ao longo das trilhas e na instalação de armadilhas de Malaise em alguns cruzamentos de trilhas. Foram percorridas 60 trilhas e instaladas 26 armadilhas, ao longo de 44 dias descontínuos de campo. Foram registradas 65 espécies de vespas sociais pertencentes a 12 gêneros. Polybia e Mischocyttarus destacaram-se como os principais gêneros em número de espécies. Agelaia fulvofasciata e Angiopolybia pallens foram as espécies mais freqüentes. Busca ativa apresentou um melhor desempenho quanto à descoberta de espécies de vespas sociais (63) do que armadilha de Malaise (26). Dois subconjuntos de 25 amostras, cujas respectivas acumulações também resultam em totais de 63 espécies, foram obtidos através do programa DIVA-GIS, demonstrando que o resultado geral do inventário poderia em tese ser alcançado com um esforço consideravelmente menor, distribuído por toda a extensão da grade. O levantamento representou um incremento de 21 espécies à lista obtida anteriormente para Caxiuanã, totalizando 100 espécies para a região, e de dois novos registros para o estado do Pará (Polybia brunnea e Mischocyttarus vaqueroi).

Composição da fauna de Hymenoptera associada a área agrícola de manejo tradicional: abelhas nativas e parasitóides

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

The social wasp fauna of a riparian forest in southeastern Brazil (hymenoptera, vespidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fauna insectorum Helvetiae. Hymenoptera. Fam. Diploptera Latr. (Vespida aut.)

Issued with Schweizerische entomologische Gesellschaft. Mittheilung, Bd. VII.

Presencia de Anagrus flaveolus en la Argentina parasitoide de un insecto dañino del trigo y maíz (Insecta - Hymenoptera - Mymaridae)

p.19-23

Efeito do turno de coleta sobre comunidades de formigas epigéicas (Hymenoptera: Formicidae) em áreas de Eucalyptus cloeziana e de cerrado

This study aimed at evaluating the effect of collect time (day and night) on ant fauna attracted to baits in areas of Eucalyptus cloeziana (Myrtaceae) and cerrado. The ants were collected in Fazenda Boa Vista, Mannesmann Fi-El Florestal Ltda, Paineiras, Minas Gerais State. Eigthteen sample units were collected: 12 in E. cloezina and six in cerrado. Each sample unit consisted of three plots (25 x 35 m each). The plot consisted of 34 baits distributed in a grid pattern at 5 m intervals. The sampling was carried out in the diurnal and nocturnal period. The results obtained revealed that both type of vegetation (cerrado x Eucalyptus) and the collect time (day x night) had a significative influence on the epigaeic ant fauna. The ordination (DCA) indicated that collect time effect was more important to fauna structuration than the vegetation effect. Brachymyrmex sp.1, Brachymyrmex sp.2, Camponotus crassus Mayr, Camponotus rufipes (Fabricius), Cephalotes pusillus (Klug) and Ectatomma brunneum Smith were indicator species of nocturnal period, and Camponotus renggeri Emery, Camponotus atriceps (Smith), Camponotus melanoticus Emery and Paratrechina sp.1 were indicators of nocturnal period.