Blue mormon (Papilio (agenor) polymnestor), a sub-species of Great Mormon, is a large swallowtail butterfly from Papilionidae family. It is the fourth largest butterfly of India with a wingspan of about 120-150mm. In June 2015, Maharashtra State Wildlife Board declared Blue mormon as their state butterfly for promoting its conservation. Blue mormon has great ecological importance as it is considered as a Bioindicator for a healthy and biodiverse forest ecosystem. It is endemic to India and Sri Lanka. 

Host plants of Blue mormon butterfly are mainly from the Citrus group. The early caterpillar instars of this butterfly have whitish spots and markings that mimics bird droppings. This helps them to camouflage. The final instar becomes vibrant, dark green and have large fake eyespots (ocelli) on their head scaring away predators. They also have a bright red, forked scent organ (osmeterium) that pops out from behind the head when the caterpillar feels threatened. It emits a strong, foul smell, making the caterpillar appear unpalatable to predators and thus acting as a self-defense mechanism for them. This butterfly completes its life cycle (from egg to larva and then to adult butterfly) within about 40-50 days. Whereas the adult butterfly lives only for about 1 week, generally females live for a bit longer than males.

They have a strong and fast flying pattern with change of course and gliding phases. In addition to nectaring, basking and roosting, males are also observed to do mud-puddling for mineral sequestration. In our campus, they often become active during midday, flying in the same loops, basking and nectaring too. To spot this butterfly is a treat to the eyes!