Fig. B14. Pea aphid mummies. In the northern half of the UnitedStates, parasitoids such as Aphidius ervi (Hymenoptera:Aphidiidae) usually prevent pea aphids from exceeding economic injury levels. Shown here are aphid mummies, in which the parasitoid pupates. Note the exit hole in the mummy on the left, cut by the emerging adult parasitoid.