Family: Lycaenidae
Large blue butterflies spend most of their larval stage inside ant nests, either eating ant larvae or being fed by the ants as if they were the ants' own brood (like cuckoos). This is an example of parasitism. The butterflies are dependent on the ants for survival, and have evolved special mechanisms to allow them to trick the ants into looking after them, even though it is against the ants own interests to do so.
This interesting Link Will Takle you to the Life Cuycle of This fascinating Butterfly Large Blue Life Cycle