Bob A knew that the caterpillars were Io moths. Good for you, Bob. Io was one of Zeus’ mortal girlfriends. Here’s what the mature moth looks like.
I was hoping too watch the pupae to see them hatch, but they disappeared into the hybiscus. My hibiscus is about 10 feet tall, and I have to prune it, so I didn’t really mind if the caterpillars were lending a hand.