Microplitis croceipes is a braconid wasp native to the US state of Georgia. It is an important parasitoid of caterpillars, including those of major agricultural pests Helicoverpa zea (formerly called Heliothis zea) and Heliothis virescens. M. croceipes uses its antennae to detect the odor of caterpillar feces. The wasp deposits a single egg inside the caterpillar; as the wasp larvae mature they feed on the caterpillar, which weakens and dies after the larvae emerge and pupate. Adult wasps emerge from their cocoons about a week after cocoon formation.