Q: I found a caterpillar hanging upside down on my lantana. Can you please tell me what kind it is and what those white things are attached to its back?
A: It looks like Rustic sphinx moth caterpillar. The moth is large ( 3″ – 5″ wingspan) and mottled black and white on its body and wings. Unless you’re looking for them at night, it’s not likely you’ll ever see an adult.
The white things on its back are the cocoons of tiny braconid wasps. The wasp adult lays eggs on the caterpillar in mid-summer. The eggs hatch soon after and the larvae burrow into the body of the caterpillar, where they feed for several weeks. When the caterpillar is almost dead, the larvae emerge and spin small white cocoons above their former lunchroom. They overwinter in the cocoons and emerge in spring, hungry for another caterpillar meal.
Since the wasps help control caterpillars that might eat garden plants, I recommend you leave the caterpillar alone and let Nature take its course.