Female alysiine wasps lay their eggs in the eggs or maggots of their hosts, and emerge from the host puparium after eating and killing the host. Thus they are "egg-pupal" or "larval-pupal" parasitoids. The hosts are cyclorraphous Diptera, which are flies with short antennae in which the adult emerges through the hard puparium through a circular opening. In the case of a parasitized fly puparium, the wasp emerges instead of the adult fly.
(2) For more info on parasitoid lifeways
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