ABSTRACT
ABSTRACT Knowledge about the spatial distribution of fruit flies (Diptera: Tephritidae) and tritrophic interactions (fruit-fruit fly parasitoid) contributes to the monitoring and maintenance of the numerical density at a level lower than economic damage. The purpose of this study was to identify the spatial distribution and associations of fruit flies with their parasitoids and host plants in the municipality of Bom Jesus-PI. The flies were obtained from fruit collection from July 2018 to May 2019. A total of 1,711 individuals were obtained, represented by six species: Anastrepha obliqua (Macquart, 1835), An. fraterculus (Wiedemann, 1830), An. alveata Stone, 1942, An. sororcula Zucchi, 1979, An. zenildae Zucchi, 1979 and Ceratitis capitata (Wiedemann, 1824). Anastrepha obliqua was the species with the widest distribution throughout the ecotone area. Ceratitis capitata is distributed only in the urban perimeter. A tritrophic relationship occurred between four species of parasitoids, Asobara anastrephae (Muesebeck, 1958) or Opius sp. associated with An. obliqua in Spondias mombin or S. tuberosa fruits. Opius sp. has also been associated with An. alveata in Ximenia americana. Pachycrepoideus vindemiae was obtained from C. capitata in Malpighia emarginata, in addition to An. obliqua in Averrhoa carambola. Therefore, fruit flies are associated with native fruit trees (S. tuberosa, S. mombin, S. purpurea, P. acutangulum, Inga laurina, X. americana) and exotic fruits (M. emarginata, A. carambola, P. guajava). Ceratitis capitata was recorded for the first time in the state of Piauí infesting I. laurina (Sw.) Willd. This is the first record of the parasitoid genus Spalangia. in An. obliqua in Piauí and in the semiarid region of Brazil.