Studies of community assembly have emphasized snapshot comparisons of spatially replicated samples from “natural” assemblages. Agro-ecosystems are characterized by relatively little habitat heterogeneity and no dispersal barriers for actively flying insects. Therefore, dynamic patterns of species segregation and aggregation are more likely to reflect the direct or indirect effects of species interactions. We studied the temporal organization of a guild of 21 congeneric species of Anastrepha that colonized fruit orchards in Monte Alegre do Sul, São Paulo, Brazil. This assemblage also included the introduced Mediterranean fruit fly Ceratitis capitata. One hundred six consecutive weekly censuses (11 Jan 2002-16 Jan 2004) of flies in guava, loquat, and peach orchards revealed a pattern of minimum abundance during the coldest months of each year (June and July) and a maximum abundance during periods of flowering and fruit ripening. Overall, phenological overlap was greater than expected by chance. However, conditioned on the pattern of seasonal abundances, temporal occurrence and abundance matrices exhibited patterns of significant species segregation and anti-nestedness. In each year, the 3 orchards contained a small number of species pairs that exhibited statistically significant temporal segregation or aggregation. Most aggregated and segregated pairs reflected seasonal shifts in species presences that were not related to variation in air temperature. Most of the significant pairwise associations involved C. capitata: 8 of the 11 segregated pairs and 2 of the 7 aggregated pairs. These results suggest that species interactions between introduced and native species can be an important determinant of species associations in agro-ecosystems.

The objective of this research was to describe the biological and morphometric aspects of the parica tree defoliator, Syssphinx molina (Cramer), and make recommendations about the insect rearing. The life cycle was 62.9 days with mean periods for the egg, larval, pre-pupal and pupal stages of 5.6, 31.1, 2.2 and 16.6 days respectively. The pupal viability was 60.5% for females and 48.6% for males. The sexual ratio was 0.5 with mean production of 182.3 ± 2.2 eggs per female and egg viability of 24.3%. The mean longevity was 7.9 ± 2 and 8.1 ± 3 days for females and males respectively. Other parameters were also observed and compared with description of other Saturniidae species.

RESUMO:Os estudos foram conduzidos em pomares de goiaba, em dois municípios do estado de Sáo Paulo. Em Monte Alegre do Sul, o levantamento foi realizado em uma estação experimental da Agência Paulista de Tecnologia dos Agronegócios, na qual foram cole tadas 13 espécies de Anastrepha, desde janeiro de 2002 a dezembro de 2003. Em Monte Alto, em pomar comercial, foram coletadas oito espécies, desde janeiro a dezembro de 2004. Anastrepha fraterculus foi a espécie mais frequente nos dois municípios. Os parâmetros cli máticos exerceram baixa influência sobre a flutuação populacional das espécies de Anastrepha, nos dois pomares. Os picos populacio nais das espécies de Anastrepha mais abundantes variaram entre os pomares. A disponibilidade de frutos no pomar e nos entornos é o fator que determina o tamanho das populações de moscas-das-frutas.

ResumoComposição das espécies de Anastrepha (Diptera: Tephritidae) em habitats com diferentes níveis de atividade antropogênica. Coletamos espécies de Anastrepha em três áreas (ambiente urbano, estação de pesquisa e agricultura) e comparamos as comunidades por índices faunísticos (dominância, abundância, frequência e constância). A diversidade de espécies foi estimada usando a estatística Q e calculando os índices Shannon, Margalef Pielou e Berger-Parker. A semelhança entre as áreas foi baseada nos coeficientes de Sørensen e Bray-Curtis. As áreas do ambiente urbano e da estação de pesquisa apresentaram maior diversidade e similaridade de espécies de Anastrepha. A composição das espécies diferiu entre as áreas, com predominância de A. fraterculus (Wiedemann, 1830) nas três áreas. Os padrões de distribuição não diferiram depois de ajustar as séries geométricas. A área agrícola era a mais diversificada e mais parecida com a área urbana em termos de abundância. A área urbana e a estação de pesquisa eram as mais diversas e eram semelhantes em composição de espécies de Anastrepha. Apesar de estarem sujeitos a diferentes níveis de perturbação humana, esses resultados sugerem que o padrão de abundância e distribuição de espécies de Anastrepha é semelhante nas três áreas. Palavras-chave: AbstractWe collected Anastrepha species in three areas (urban, research station, agricultural) and compared communities by faunal indices (dominance, abundance, frequency, and constancy). Species diversity was estimated using the Q-statistic and by calculating Shannon, Margalef Pielou and Berger-Parker indices. Similarity among areas was based on Sørensen and Bray-Curtis coefficients. The urban and research station areas presented greater diversity and similarity of Anastrepha species. Species composition differed between areas, with predominance of A. fraterculus (Wiedemann, 1830) in the three areas. Distribution patterns did not differ after adjusting the geometric series. The agricultural area was the least diverse and more closely resembled the urban area in terms of abundance. The urban area and research station were the most diverse, and were similar in composition of Anastrepha species. Despite being subject to different levels of human disturbance, these results suggest that the abundance and distribution pattern of Anastrepha species are similar in all three areas.

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