This paper aimed to characterize the fruit fly populations in four municipalities of the Northwest region of Rio de Janeiro State (Bom Jesus do Itabapoana, Italva, Itaperuna and Natividade), performing a faunistic analysis of the specimens of fruit fly collected with plastic McPhail traps in commercial orchards of guava (Psidium guajava L.) and orange (Citrus sinensis Osbeck), and backyard gardens during a two year period. The total of 29,909 females of Ceratitis capitata (Wied.) and 27,621 females belong to 16 species of Anastrepha Schiner was collected. The highest value of the Shannon index was reported in Bom Jesus do Itabapoana (H = 0.96), as well as highest species richness (S = 14). Fruit fly populations had low diversity indexes (alpha = 1.1 - 1.5). The predominant species (more frequent, more abundant, constant and dominant) were C. capitata in Natividade and Bom Jesus do Itabapoana, and A. fraterculus (Wied.) in Italva and Itaperuna. Regarding fruit fly species composition, the population in Natividade and Bom Jesus do Itabapoana were more similar between each other, composing a distinct group of the fruit fly populations from Italva and Itaperuna, which composed another group.
Insecta; Anastrepha; Ceratitis capitata; diversity; faunistic index
