Buzzing Bombyliid

These large, showy flies are common here, buzzing conspicuously around the yard. They are called bee flies, family Bombyliidae, because they sound like bees. Some species look like bees too, but this one doesn't (at least, not to me). Their larvae are parasitic on the larvae of other insects. Caterpillars, grubs, hymenopteran larvae in their nests, and grasshopper eggs are common hosts. I've read that after the bombyliid flies lay eggs on a wasp's nest, each fly hatchling crawls into a brood cell and waits until the wasp larva has completely consumed the paralyzed prey its own mother has provided. The maggot then consumes the fully-fattened wasp larva.

The adults feed harmlessly on nectar and pollen.

• Bombyliidae page at the Tree of Life Project
• Bombyliidae page from John L. Foltz at the University of Florida