koinobiont

Koinobiont describes a type of parasitoid—an organism that develops inside or on a host and eventually kills it—that allows its host to continue living, feeding, and growing while the parasite develops within.

This contrasts with idiobionts, which immediately paralyze or kill their hosts.

Koinobionts are typically wasps or flies whose larvae develop inside caterpillars or other insects that remain active until the parasite matures.

Many koinobiont wasps are used in biological pest control programs.