| Abstract: | A laboratory study was performed to examine the importance of the parasitoid egg in host discrimination by Cephalonomia stephanoderis Betrem (Hymenoptera: Bethylidae), an ectoparasitoid of the coVee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae). C. stephanoderis was able to distinguish between parasitized and unparasitized hosts, and preferred to oviposit on the latter. This discriminative ability appeared to be innate, not learned. W hen the parasitoid egg was removed artificially the host was accepted for parasitism once more, suggesting that the presence of the egg is the most important factor in host discrimination. However, it was not possible to exclude the eVect of a chemical marker present either on or within the host, and/or associated with the presence of the parasitoid egg. |
