Parasitoids differ from parasites in that they:
Parasitoids develop in or on a single host and normally require that host's death to complete their life cycle. Many parasitoid wasps lay eggs in caterpillars or other arthropods; larvae consume host tissues progressively, often delaying lethal damage until development is nearly complete. Typical parasites exploit a host for resources but generally gain from keeping it alive long enough for repeated feeding or transmission, so host death is not an obligatory endpoint. Parasitoids may be internal or external, and they certainly harm rather than coexist harmlessly with hosts. Their combination o
Ref: Ecology: From Individuals to Ecosystems, Begon et al., 5th Ed., Ch. 8-13
