The Importance of Taxonomy to Biological Control as Illustrated by the Cryptic History of Aphytis Holoxanthus N. Sp. (Hymenoptera: Aphelinidae), a Parasite of Chrysomphalus Aonidum, and Aphytis Coheni N. Sp., A Parasite of Aonidiella Aurantii1

Past misidentification of Aphytis holoxanthus n. sp. as Aphytis lingnanensis Comp. retarded its use and distribution in various countries for the biological control of Chrysomphalus aonidum (L.). To a lesser degree the same applies also to Aphytis coheni n. sp., a parasite on Aonidiella aurantii (Mask.) in Israel, which was thought to be Aphytis lingnanensis. The correct identification makes an additional parasite species available for testing in biological control attempts against Aonidiella aurantii. Aphytis holoxanthus and Aphytis coheni are described as new species. A key separating them from other similar appearing species is given.