Both the adults and larvae of Encarsia formosa can kill whiteflies by causing physical injuries and feeding internally on them. Briefly, adult wasps puncture the body of whitefly nymphs or pupae with their ovipositor and feed externally on the oozing blood (hemolymph) and the body content of the nymphs or pupae. Also, females of Encarsia formosa lay eggs using their ovipositor inside the body of adults and nymphs of whiteflies. After hatching from eggs, the wasp larvae will then start feeding internally on the body content of whitefly nymphs or pupae and eventually kill them.