none Lymantria dispar; AGE-; Larva, effect on hymenopteran parasite development; HYMENOPTERAN-PARASITES; Glyptapanteles liparidis; Parasite development, effect of host larva age Glyptapanteles liparidis; DEVELOPMENT-; Lepidopteran host larva age relationships; LEPIDOPTERAN-HOSTS; Lymantria dispar; Parasite development, effect of host larva age The endoparasitic development of G. liparidis was examined in 3 different host stages of gypsy moth larvae. Due to the variation in the number of parasites per host, no difference was observed between the hosts parasitized at various stages; however, a tendency for later parasitized hosts to contain more parasite larvae was evident. The nutritional conditions of the moth parental generation influenced both host and parasite development. On the other hand no influence of host age was observed on emergence dates of larvae and wasps.