common names: Red-Tailed Tachina, Tachinid Fly
scientific name: Order Diptera, family Tachinidae, Winthemia quadripustulata
size: Adult--3/8" to 1/2"
identification: Adult flies are bristled or have fine hairs on the body. They look like big house flies. Larvae are thick-bodied maggots with tiny spines or plates. Caterpillar and beetle larvae get very agitated when trying to keep these flies from landing on them.
biology and life cycle: Adults lay white oval eggs on host insect's body. Wings are slightly spread when at rest. Eggs hatch in a few days. Larvae enter the host after hatching and feed internally, then bore out of the host to pupate in the soil in a barrel-shaped pupal case. Tachinids overwinter as pupae or larvae in the host's body. Usually have more generations than their hosts. Sometimes eggs are laid on foliage near caterpillars so they will be eaten and hatch inside.
habitat: Many landscape and food crops, especially dill, parsley, sweet clover, yarrow, and other flowering herbs. They especially like buckwheat, alyssum, and daisies.
feeding habits: Larvae feed on caterpillars, beetles, fly larvae, true bugs, corn borers, corn earworms, imported cabbage worms, cabbage loopers, potato stem borers, cutworms, armyworms, Mexican bean beetles, Colorado potato beetles, stink bugs, squash bugs, tarnished plant bugs, cucumber beetles, sawflies, and grasshoppers. Adults feed on pollen, nectar, and honeydew or sometimes aphids and leafhoppers.
economic importance: Help to control many troublesome insects. Tachinid larvae destroy the eggs of many pest insects, including caterpillars, beetles, true bugs, flies, crickets, grasshoppers, and katydids.
natural control: Birds and lizards.
organic control: None needed--extremely beneficial insect
insight: Looks like an ordinary house fly. Doesn't bite.