Britain's rarest butterfly is the simply-named large blue, once coveted by collectors and almost driven to extinction. Now it is legally protected because they cannot be bred in captivity. Why not? That's the really weird part.
The remarkable life cycle of the large blue means it can only thrive in very particular habitats. Eggs are laid on the flower buds of wild thyme or marjoram. The larvae burrow into the flower heads and when they are about 4mm long drop to the ground and wait to be found by foraging red ants, attracting them with sweet secretions from a “honey” gland. The ants place them in their brood chamber and the larvae feed on ant grubs. They turn into butterflies, crawl above ground, and fly in midsummer.
An article at The Guardian about a case of butterfly poaching tells us how the large blue was re-introduced to Britain after it was declared extinct there in the '70s. -via TYWKIWDBI
(Image credit: PJC&Co)