The parasitism of Bemisia tabaci (Genn.) biotype B nymphs on cotton plants was observed during a research on resistance of cotton genotypes to this whitefly. The experiment was set in a greenhouse at the Experimental Station of the Instituto Agronômico (IAC), in Campinas, São Paulo State, Brazil. Samples of the parasitized nymphs were collected and maintained in laboratory to monitor the parasitism and obtain the adult parasitoids. A total of 129 adult parasitoids were obtained, including one Encarsia inaron (Walker), 13 En. lutea (Masi), and 115 Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae). This is the first report of Er. mundus in Brazil.
biological control; parasitism; silverleaf whitefly