Effects of Multiple Parasitism on the Gypsy Moth Parasites Apanteles melanoscelus (Hymenoptera: Braconidae) and Compsilura concinnata (Diptera: Tachinidae)

Neither Apanteles melanoscelus (Ratzeburg) nor Compsilura concinnata (Meigen) females discriminated against gypsy moth larvae parasitized by variously aged individuals of the other species. In host larvae parasitized by both species, neither parasite consistently destroyed the other, and both parasites emerged from about 11% of the hosts. Dissections did not reveal any obvious instances of physical attack or physiological suppression of one species by the other, and parasite developmental rates appeared to be the same in multiple-parasitized hosts as in single-parasitized ones. The study suggests that these two parasites are tolerant of each other when in the same host and that probably no direct intrinsic competition occurs between them