Identification: About the size of a large housefly. Thorax is mostly black. Abdomen is bright orange. Has a fringe of comb-like black hairs on rear legs. Smokey wings. The wings of males have a darker area. The abdomen tip of females is black.
Range: Native to North America and found in most areas.
Food: Adults feed on nectar. Larva are parasites of certain true bugs, primarily squash bugs and stink bugs.
Habitat: Found wherever crops that will attract its host species are growing. Often hovers over squash plants searching for prey. (BugGuide Species Page)
Life Cycle: The female fly lays one to many small, white or gray, oval eggs on large nymphs or adult bugs. The larvae burrow from the egg directly into the bug's body. Only one larva survives within each pest bug. A large, cream-colored maggot exits from the body of the bug, drops to the ground, and pupates in a dark reddish-brown, capsule-like puparium. The bug soon dies. A new generation of adult flies emerges to lay eggs about two weeks later. Each female fly may lay several hundred eggs, and there may be three generations each year, depending on location. The parasitoid overwinters as a larva within the body of the overwintering bug, emerging in late spring or early summer. (Cornell University ... site also includes photos of several life cycle stages)
Remarks: T. pennipes appears to have different biotypes across the country, preying on very specific hosts in different regions. (Cirrus Images)
The stinkbug "stink" that repels many predators, seems to attract T. pennipes.
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