An artificial aphid was developed by making parafilm(R) bubbles filled with aphid haemolymph and its suitability for parasitoid oviposition was tested. Aphidius ervi accepted the parafilm(R) aphid and laid eggs on it. By stretching, the thickness of the parafilm could be changed. The thicker the parafilm, the higher was the mean number of ovipositional stings and the lower the mean number of eggs released by A. ervi. none