An egg is injected by the female fly into the shoulder joint of an ant worker.

Soon after, the egg undergoes rapid inflation as it appears to absorb ant hemolymph.

This first instar larva migrates into the ant head and consumes the jaw muscle and other tissues, leaving the mandibles hanging and preparing a future exit space.

After about two weeks, the ant worker is termed a "zombie" because the fly larva has effectively taken control.

[2][3] The fly pupates in the detached head capsule, requiring a further two weeks before emerging through the ant's mouth.