[1] Adult Aphidius is a small wasp, usually less than 1⁄8 inch (3.2 mm) long.

When the eggs hatch, the wasp larvae feed on the inside of the aphid.

As the larvae mature, the hosts die and become slightly enlarged or mummified, often becoming tan or yellow.

The adult parasite chews the sugar out of the mummy leaving a hole.

The genus Aphidius includes many species that provide biological pest control of aphids on agricultural crops, greenhouses, urban landscape and home gardens.