PALAVRAS-CHAVE: Ecologia, Polistinae, manguezal, restinga, Mata AtlânticaABSTRACT -We studied the structure and composition of communities of social wasps associated with the three insular ecosystems: mangrove swamp, the Atlantic Rain Forest and the ´restinga´-lowland sandy ecosystems located between the mountain range and the sea. Three hundred and ninety-one nests of 21 social wasp species were collected. The diversity of wasps found in each ecosystem was significantly correlated to the diversity of vegetation in each of the three physiognomies, (r 2 = 0.85; F(1.16) = 93.85; P < 0. 01). The Tropical Atlantic Forest physiognomy had higher species richness (18 species), followed by the restinga (16 species) and the mangrove (8 species) ecosystems.

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Este estudo teve por objetivo identificar as espécies utilizadas como recurso alimentar e descrever os padrões locais de utilização de frutos de cactos como recurso alimentar por vespas sociais em uma área de Caatinga. Novecentos e oito indivíduos de nove espécies de vespas foram capturados visitando seis espécies de cactáceas. Cereus jamacaru DC. e Pilosocereus catingicola (Gurke) Byles & G.D foram as cactáceas mais utilizadas por vespas sociais, tanto em número de espécies quanto de indivíduos. Polybia paulista von Ihering, 1896, Polybia ignobilis (Haliday, 1836), Polistes versicolor (Olivier, 1791), Polistes simillimus Zikán, 1951, Polistes billardieri Fabricius, 1804, Polistes canadensis (Linnaeus, 1758), Polybia occidentalis (Olivier, 1791) e Polybia sericea (Olivier, 1705) apresentaram as maiores amplitudes de nicho trófico. As maiores sobreposições no nicho trófico foram observadas entre Mischocyttarus lanei Zikán, 1949 e Polistes simillimus Zikán, 1951 (0,83). Os altos níveis de sobreposição de nichos observados são explicados em função do comportamento generalista das vespas sociais, bem como da exploração intensiva de poucas espécies de cactáceas.

Neotropical Entomology 37(6): 691-701 (2008) Estudos Morfológicos das Castas da Vespa Polistinae Enxameadora Neotropical, Angiopolybia pallens (Lepeletier) (Hymenoptera: Vespidae)RESUMO -As vespas neotropicais enxameadoras possuem colônias poligínicas e uma variação muito grande em relação à diferenciação das castas, desde espécies em que rainhas e operárias possuem formas e tamanhos semelhantes até aquelas em que grande diferença na forma e no tamanho são observados. Estudos morfométricos utilizando oito medidas corporais em nove colônias de Angiopolybia pallens (Lepeletier) foram realizados a fi m de aumentar o conhecimento sobre diferenciação de castas em Epiponini, empregando-se análise canônica discriminante e teste t de Bonferroni. Os indivíduos foram dissecados para determinar o nível de desenvolvimento ovariano e as espermatecas foram removidas para verifi car a ocorrência de inseminação e assim defi nir os três grupos de fêmeas: rainhas (ovários desenvolvidos e espermateca fecundada), intermediárias (ovários desenvolvidos e espermateca não-fecundada) e operárias (ovários não-desenvolvidos). Apesar de serem encontradas diferenças signifi cativas para algumas medidas em sete das nove colônias, a análise multivariada (lambda de Wilks) mostrou que as castas são de difícil distinção apenas pela morfologia. É possível concluir que diferenças morfológicas entre castas de A. pallens são pequenas ou ausentes, o que refl ete o plano basal para os Epiponini, i.e. padrão pós-imaginal de diferenciação castas. PALAVRAS-CHAVE: Inseto social, morfometria, Epiponini, diferenciação de castasABSTRACT -Neotropical swarm-founding wasps present polygynic colonies and a great variation in relation to caste differentiation, ranging from species in which queens and workers are similar in shape and size to those where variation in shape and size is conspicuous. Canonical discriminant analysis and Bonferroni t-test analysis on morphometric data collected from eight body parts of specimens from nine colonies of Angiopolybia pallens (Lepeletier) were undertaken as a step towards to a better understanding on caste differenciation in Epiponini. All specimens were dissected to verify the ovary developmental stage, and the spermatheca was removed to check for the mating status. Females were then grouped as queens (mated with developed ovaries), intermediates (virgin with developed ovaries) and workers (virgin with undeveloped ovaries). Even though differences were found for some measurements in seven out of the nine colonies evaluated, multivariate analysis (Wilks' lambda values) indicated castes could not be reliably distinguished only by morphology. We conclude that morphological differences among A. pallens castes are low or absent, refl ecting a possible groundplan for the Epiponini, i.e. a post-imaginal pattern of caste differentiation.

Lippia is one of the main genera in the family Verbenaceae, with 200 species described. Despite its richness in bioactive molecules, with several scientifically proven applications, there is little information on the insecticidal potential of its species. This study aimed to assess the insecticidal potential of essential oils from the species Lippia thymoides (Martius & Schauer); Lippia lasiocalycina (Schauer) and Lippia insignis (Moldenk) against Nasutitermes corniger (Motschulsky) (Isoptera-Termitidae). Insecticidal activity was evaluated by exposure to a contaminated surface, whereby plastic pots were lined with filter paper and imbibed in 1.5 ml of solution containing essential oils (10 µl/ml), with 10 N. corniger specimens per pot. The mortality count was performed at 24 and 48 h. The LC50 was determined by diluting the essential oils to concentrations of 0, 0.625, 1.25, 2.5, 5.0 and 10 µl/ml, which were chemically analyzed by GC-FID and GC-MS. The data indicated high toxicity for the essential oils for the Lippia species tested. The lowest LC50 (0.46 µl/ml) was recorded for L. lasiocalycina. The most common constituents were β-myrcene and (E)-ocimenone in essential oil of L. lasiocalycina, β-myrcene and limonene for L. insignis, and (E)-caryophyllene and caryophyllene oxide for L. thymoides. The results demonstrate the viability of developing biopesticides for N. corniger control.