Like many other beetles, the Epilachninae are hosts to parasitoid wasps that variously attack the eggs or larvae.
Many species are parasitoids that attack host eggs or larvae; hence they are often used as biological pest control agents, especially against aphids.
Ascoviruses evolved from iridoviruses (family Iridoviridae) that also attack lepidopteran larvae and are likely the evolutionary source of ichnoviruses (family Polydnaviridae).
Some are preparations of bacteria that attack only larvae of a certain age.
Some of the embryos become sterile "precocious" larvae that can apparently attack other larvae trying to use the same host-including, potentially, their own siblings (Ode and Hunter 2002).
It has been known to attack and consume other larvae of the same species.
They are good as new, ready to attack carpenterworms, cutworms, armyworms, fruit flies and other larvae on which they feed.
A more recent acquisition of an Australian company's bioinsecticide group gave Ecogen access to beneficial nematodes that attack insect larvae.
Parasitoids successfully employed against the cereal leaf beetle as agents of biological control include the parasitic wasps Diaparsis carinifer, Lemophagus curtus, and Tetrastichus julis, which attack larvae, and Anaphes flavipes, which is an egg parasitoid.