A few days back, During the peak rainy season, the Chandni tree (Pinwheel flower) leaves started disappearing mysteriously. I saw quite a few branches were becoming naked but there was no sign of fallen leaves anywhere, neither there was a single dry/pale leaf on the entire tree. one late evening, I saw a huge caterpillar, the size of my middle finger. The way it wolfs down the leaves was totally insane, like 90 sec/leaf. 2 days later a few of them turned black/ greyish. They were crawling around the ground, looking for a safe place to pupate. I kept one of them in a jar as suggested by @meetingmysticalcreatures. Last night one came out of the “closet” and it looks so psychedelic.
P.S. no one around here has ever seen these guys before, it still a mystery for me how it did reach here in one of most arid regions of east Rajasthan.