Actia interrupta (Curran)
Nilea erecta (Coquillett)
Hemisturmia parva (Bigot)
The adults are similar to a housefly but are covered with stiff hairs (A, center). The larvae have the appearance of small maggots and feed inside caterpillars and other hosts. Females lay their eggs on the back of several species of caterpillars, such as the obliquebanded leafroller [Choristoneura rosaceana. and (A, right)], stink bugs and on the cocoons of the forest tent caterpillar (Malacosoma disstria). The pupa of A. interrupta often can be found on the leaf next to the dead obliquebanded leafroller larva (A, left).
Several species commonly occur in many orchard plantings, and can significantly reduce caterpillar populations if not disrupted by pesticide sprays. Their abundance varies from year to year, at least partly in response to weather conditions.
The MSU IPM Program maintains this site as an access point to pest management information at MSU. The IPM Program is administered within the Department of Entomology, fueled by research from the AgBioResearch, delivered to citizens through MSU Extension, and proud to be a part of Project GREEEN.