How to Manage Pests
Identification: Natural Enemies Gallery
Cottony cushion scale parasite
Scientific name: Cryptochaetum iceryae
The parasitic fly, Cryptochaetum iceryae, and the vedalia beetle were imported from Australia to California in the late 1880s to control cottony cushion scale. They provide complete biological control of cottony cushion scale on most hosts in California and elsewhere in the world where they have been introduced, unless disrupted by adverse conditions such as pesticide applications. Cryptochaetum apparently predominates in coastal areas; vedalia is most abundant in the Central Valley and desert areas of California. Both species can occur in interior areas of California if cottony cushion scale is present.
The Cryptochaetum adult is a dark blue or green to black fly, about 1/12 inch (2 mm) long, with short rounded, grayish wings. One fly generation requires about 1 month in summer, with up to five or six generations developing per year. The female Cryptochaetum parasite lays one egg in small scales and a dozen or more in larger hosts. The larva feeds and usually pupates inside its host. Pupae are black with two tiny protruding breathing tubes (spiracles). Metamorphosis is complete.