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Beginner

Scientific Names
Actia interrupta (Curran), Nilea erecta (Coquillett) and Hemisturmia parva (Bigot)

Identification
Eggs:

• White.
• Oval.
• Laid directly on the host or directly into the host, singly or in groups.

Larvae:

• Feed internally within hosts and have a maggot-like appearance.

Pupae: 

• Found outside the body of the host.
• They are brown, elongate, and lack any obvious external features. 
• Exit holes may be found on the body of the host insect.

Adults:

• Medium to large flies, similar in appearance to houseflies but covered with prominent bristles.

Often Confused With

• Houseflies – Adult parasitic flies are similar in appearance to houseflies but covered with prominent bristles. 

Interaction With Host
Tachinids overwinter as pupae in leaf litter. Adults emerge in spring and mated females lay eggs on the back of hosts, including obliquebanded leafroller (OBLR). Development occurs within the parasitized larva. Mature tachinid larvae exit the host to pupate.

Insects Attacked
Tachinid flies as a group have a very large host range that includes many caterpillar pests; beetles; bees, wasps and sawflies; stink bugs; and grasshoppers.   

Monitoring and Management
Monitoring for tachinids is not a normal routine practice during scouting, but they may be observed during sampling of terminals for obliquebanded leafroller.

Advanced

Scientific Names
Species include Actia interrupta (Curran), Nilea erecta (Coquillett) and Hemisturmia parva (Bigot).

Identification
Eggs: White, oval, laid directly on the host or directly into the host. May be laid singly or in groups. 

Larvae: Larvae feed internally within hosts and have a maggot-like appearance.

Pupae:  Pupae are found outside the body of the host. They are brown, elongate, and lack any obvious external features. Exit holes may be found on the body of the host insect.

Adults: Adults are medium to large flies, similar in appearance to houseflies but covered with prominent bristles.

Often Confused With

• Houseflies – Adult parasitic flies are similar in appearance to houseflies but covered with prominent bristles. 

Interaction With Host
Tachinids overwinter as pupae in leaf litter. Adults emerge in spring and mated females lay eggs on the back of hosts, including obliquebanded leafroller (OBLR). Development occurs within the parasitized larva. Mature tachinid larvae exit the host to pupate. Rates of parasitism are highly variable, but research in Michigan indicted of the 11-26% percent (overwintering and summer generations respectively) of OBLR parasitized in commercial apple blocks, 36% were attacked by tachinid flies.

Insects Attacked
Tachinid flies as a group have a very large host range that includes many caterpillar pests; beetles; bees, wasps and sawflies; stink bugs; and grasshoppers.   

Monitoring and Management
Monitoring for tachinids is not a normal routine practice during scouting, but they may be observed during sampling of terminals for obliquebanded leafroller.