RESUMEN
ABSTRACT The study of arthropod communities foraging on monocultures of native plants (e.g. Caryocar brasiliense) in biodiversity hotspots (e.g. Brazilian Cerrado) is important to understand the processes driving their performance. This study evaluated the possible interactions between galling herbivores, free-feeding arthropods, and of their natural enemies on C. brasiliense trees, in an orchard (monoculture). The possible competition observed were: i) between galling insects with defoliators and phytophagous mites, ii) between sucking insects, iii) between phytophagous mites and, iv) between Aphis gossypii (Hemiptera: Aphididae) with Histiostoma sp. (Acari: Histiostomidae) on C. brasiliense trees. Numbers of predators and prey, parasitoids and hosts, and predators and parasitoids were directly related among them. The competitive interactions between herbivorous predator and parasitoid may reduce Eurytoma sp. (Hymenoptera: Eurytomidae) populations, a potential pest of C. brasiliense. The predator Zelus armillatus (Hemiptera: Reduviidae) and the parasitoids Sycophila sp. (Hymenoptera: Eurytomidae) and Ablerus magistretti (Hymenoptera: Aphelinidae) are important to determine the numbers of Eurytoma sp. and of its galls. These natural enemies may be important to control this galling insect on C. brasiliense trees. The arthropod competition affected their guild associated to C. brasiliense trees.