In general, species of Aphytis are the most effective of California red scale parasites. Species of Comperiella, Prospaltella, Physcus, Aspidiotiphagus and Habrolepis are usually less effective but may act in a complementary manner. Several species of Aphytis are recorded to be partially to completely effective in biological control of the California red scale, Aonidiella aurantii (Maskell), in various citrus producing countries. Aphytis melinus DeBach, originally from India and Pakistan, is now established in California, Argentina, Australia, Greece, Israel, Cyprus, South Africa, and elsewhere. Aphytis lingnanensis Compere, originally from southeast China, is now in California, Mexico, Texas, and elsewhere. Aphytis coheni Debach is important in Israel; A. chrysomphali (Mercet) has been of some consequence in California, Australia, Greece, Israel, and elsewhere; and A. africanus Quedneau is considered important in South Africa.

Max Badgley and Stan Warner were responsible for the successful quarantine handling involved and Stan Warner for subsequent culture. Chuck Kennett's important role in collecting the parasites is discussed in the text. Financial support of this work by the Citrus Advisory Board is gratefully acknowledged.