Lespesia aletiae; LEPIDOPTERAN-HOSTS; Simyra henrici; New host record; INDIANA-; West Lafayette, Purdue-Baker Wildlife Area; New lepidopteran host record Simyra henrici; DIPTERAN-PARASITES; Lespesia inermis; New host record; HYMENOPTERAN-PARASITES; Aleiodes stigmator & Microplitis quadridentatus; Parasitism of larvae including new host & hyperparasite records; HYPERPARASITISM-; New hymenopteran parasite & hyperparasite records from larvae; INDIANA-; West Lafayette, Purdue-Baker Wildlife Area; Parasitism of late instar larvae including new records Aleiodes stigmator; HYMENOPTERAN-PARASITES; New hyperparasite records, lepidopteran host, Indiana HYMENOPTERA-; HYMENOPTERAN-HOSTS; Aleiodes stigmator; New host records, hyperparasites of Lepidoptera; LEPIDOPTERAN-HOSTS; Simyra henrici; Parasitism of larvae including new host & hyperparasite records; HYPERPARASITISM-; New hymenopteran host records, parasites of Lepidoptera; INDIANA-; West Lafayette, Purdue-Baker Wildlife Area; Parasitism of lepidopteran host larvae including new records. Parasitism of the cattail caterpillar, Simyra henrici (Grote) (Lepidoptera: Noctuidae), was assessed over a two-year period in Indiana. Larvae collected from smooth bromegrass, Bromus inermis Leyss. (Gramineae), yielded eight species of parasitoids in two orders. Primary parasitoids included Lespesia aletiae (Riley) (Diptera: Tachinidae), Microplitis quadridentatus (Provancher) (Hymenoptera: Braconidae), and Aleiodes stigmator (Say) (Hymenoptera: Braconidae). Secondary parasitoids included Gelis tenellus (Say), Gelis sp. (Hymenoptera: Ichneumonidae), Conura meteori (Burks) (Hymenoptera: Chalcididae), Catolaccus cyanoideus Burks (Hymenoptera: Pteromalidae), and Trichomalopsis dubius (Ashmead) (Hymenoptera: Pteromalidae). For the numerically dominant parasitoid, A. stigmator, more individuals emerged from larger hosts. Emergence success for this species depended on the number of parasitoids per larva and the configuration and location of parasitoid pupation cells. Sex ratios of A. stigmator were female-biased and not related to host size. Approximately 46% of hosts contained hyperparasitoids. The presence of hyperparasitoids apparently had little impact on primary parasitoid production. The pest potential and natural control of S. henrici are discussed. none