It’s become one of my annual rituals.
Each year, post Xmas, I pay a visit to a stand of Silver Wattles near Yandoit.
They are home to a colony of Common Imperial Blue Butterflies Jalmenus evagoras aka the Imperial hairstreak or simply the Imperial blue.
In common with many Australian butterflies this species has a fascinating and complex life history, of which Iridomyrmex ants play a key part. The larvae of this butterfly feed on the foliage of numerous species of acacias, locally I’ve only found them on Silver Wattle Acacia dealbata. The ants live in underground nests and emerge to provide protection for the caterpillars from predators and parasitoids. The reproductive success of the butterfly is significantly improved from this protection, meanwhile the ants profit from supping on sugary secretions produced by the larvae.
On most recent visits to the colony the adult butterflies have kept their wings folded. Yesterday however, was a cool morning and the butterflies were warming up – fully opening their wings to absorb the rays of the sun, displaying the brilliant metallic blue from which J.evagoras gets its common name.
You can learn more about the Common Imperial Blue Butterfly and its life history here and here.
The blog, Life in a Southern Forest, has a terrific story about the behaviour of the butterfly – click here.
Imperial Blue Butterfly, Yandoit, 7th January 2022
Mating
Larva, pupae and ant attendants
Pupae with cocooning larva at top
Adult butterfly … showing some wear and tear
Post mating
Courtship behaviour
II
Mating
The magnificent Imperial Blue Butterfly
Natural Newstead 
Wonderful photos of these beautiful creatures. They Look very imperial .
Amazing photos
An excellent post showing the full process. Great job and thanks for sharing Geoff and keep on with the ritual!