Adenotrophic viviparity

Adenotrophic viviparity means "gland fed, live birth". This is the reproductive mode of insects such as tsetse flies (Glossinidae), keds (Hippoboscidae) and bat flies (Streblidae and Nycteribiidae) as adenotrophic viviparity is a characteristic feature of the superfamily Hippoboscoidea.
Adenotrophic viviparity differs from ovoviviparity in that the eggs (usually one at a time) are retained within the female's body, hatch and are nourished through "milk glands" until the developed larvae are ready to pupate. The larvae are then 'larviposited' and immediately pupate. This is one way insects avoid predation during their most vulnerable life stage. In ovoviviparity one or more egg hatches internally in the female, but they are not nourished after hatching and are immediately 'larviposited' and continue their development outside the female.