1. UC IPM
Relative size of adult <i>Trioxys pallidus,</i> a parasite of walnut aphids, <i>Chromaphis juglandicola.</i>.
Relative size of adult Trioxys pallidus, a parasite of walnut aphids, Chromaphis juglandicola..
Credit: Goulet H, Huber JT. 1993. Hymenoptera of the World: An Identification Guide. Agriculture Canada, Ottawa, Ontario. Adapted by UC IPM.