Padrão de sobreposição e co-ocorrência interespecífica de moscas-das-frutas (Diptera, Tephritidae, Anastrepha) em áreas antropizadas

Abstract

Overlap pattern and interespecific co-ocurrence of fruit flies (Diptera, Tephritidae, Anastrepha) in anthropic areas The niche overlap pattern and co-ocurrence, as well as positive and negative interactions among Anastrepha species, based on abundance matrix data and presence-absence data was evaluated. The populations of species of Anastrepha was analyzed quantitatively to evaluate its distribution and the populational fluctuation of predominant species. The study was carried out in two anthropic areas, Fazenda Areão and Monte Olimpo, at "Luiz de Queiroz" campus, Universidade de São Paulo, Piracicaba, SP. The research was based on 52 samplings obtained over 14 McPhail traps distributed in these two areas. It was captured 1,583 females belong 14 species: A. amita Zucchi, A. barbiellinii Lima, A. bistrigata Bezzi, A. daciformis Bezzi, A. distincta Greene, A. fraterculus (Wiedemann), A. grandis (Macquart), A. manihoti Lima, A. montei Lima, A. obliqua (Macquart), A. pickeli Lima, A. pseudoparallela (Loew), A. serpentina (Wiedemann) and A. sororcula Zucchi. It was collected more specimens (1,041) at Fazenda Areão, comparing with the ones at Monte Olimpo (542), that showed the highest species diversity index. Anastrepha fraterculus, A. obliqua and A. pseudoparallela were the predominant species at Fazenda Areão; at Monte Olimpo, only A. fraterculus and A. pseudoparallela were predominant. The niche overlap mean was higher than randomly expected for these two areas. Therefore, the species ecological niches mostly overlap. The coocurrence pattern indicated the ocurrence of two non-randomized pair of species that segregated: A. pseudoparallela x A. obliqua at Fazenda Areão, and A. fraterculus x A. pseudoparallela at Monte Olimpo. The segregation indicates that can exist three aggregated pairs: A. bistrigata x A. montei and A. fraterculus x A. barbiellinii at Fazenda Areão; and A. fraterculus x A. bistrigata at Monte Olimpo, indicating that each pair coexists pacifically, with no interference in the permanence of the fruit fly populations in the areas. The highest populational level occurred from August to December, when temperatures oscillated between 18 and 24°C, with the population peak in September.