The infestation level was 3.2 times higher in Chrysophyllum gonocarpum (aguay) than in Inga marginata (pacay), despite the greater number of pacay fruit collected (2.5-fold differences). A positive correlation between fruit size and number of A. fraterculus pupae per fruit was observed in both host plant species, but these associations were due to weak correlation coefficients in aguay (Rs = 0.17, P = 0.03, n = 168, minimum and maximum individual fruit weight: 4.5-10.5 g) and pacay (Rs = 0.19, P < 0.001, n = 407, minimum and maximum individual fruit weight: 8.3-39.4 g). In total, 87 A. fraterculus pupae and 9 Ceratitis capitata pupae were recovered from all infested aguay fruits. From A. fraterculus pupae, 32 adult flies (37% emergence rate) and one adult parasitoid [Aganaspis pelleranoi (Brèthes) (Hymenoptera: Figitidae, Eucoilinae)] were recovered, and from C. capitata pupae, 3 adult flies (33% emergence rate) were obtained. Of the 168 A. fraterculus pupae recovered from all infested pacay fruits, 64 adult flies (38% emergence rate) and nine adult parasitoids were obtained [8 Doryctobracon brasiliensis (Szépligeti) (Hymenoptera: Braconidae, Opiinae), and 1 A. pelleranoi]. Parasitism rates were 12.3% and 3% in I. marginata and C. gonocarpum, respectively. none