In studies conducted from april through november 1979 and 1980, in the 5th Region, Chile (Lat. 32º - 33º S), the parasitoid Aphidius ervi Haliday and the complex A. rhopalosiphi-uzbekistanicus were recovered from mummies collected on Avena fatua L., Bromus rigidus Roth, Bromus trini (Desv.), Hordeum murinum L., Lolium multiflorum (Lam.) and Phalaris sp. Myzus persicae (Sulz.), also parasitised by these same species, was found on Anoda sp., Brassica campestris L., Convolvulus arvensis L., Cynara sp., Oxalis sp., Raphanus sativus L., and Rumex sp. The parasitoids' large range of alternative hosts, possibly contributedto their survival and goOO establishment when liberated in Chile.