Cloudless Sulphur Caterpillar

what is this caterpillar?
Hi Bugman,
I found this caterpillar in Santa Barbara, California. I found it interesting that it matched the color of the plant I found it on. I have looked around a bit on the web to identify it without any luck. Can you help? Also, any idea which plant it is eating? Thank you!!
Dan Sullivan

Hi Dan,
This is a Cloudless Sulphur Caterpillar, Phoebis sennae, also called the Senna Sulphur. The butterfly is a large, clear yellow, fast flying species. The plant is Senna. As a means of camouflage, the caterpillars are often green when feeding on the leaves, and yellow when feeding on the blossoms.

2 thoughts on “Cloudless Sulphur Caterpillar”

  1. We found a whole group of the cloudless sulphur caterpillar on our small cassia plant that we bought in Palm Springs a few years ago.

    We are wondering what it will look like as a butterfly. I guess we will look up the same name but in a butterfly. Oh, yes are they a harm to our plant because we would hate to have to relocate them. Also, will they cocoon on the Cassia or move to a more private area?

  2. I planted a Cassia Popcorn tree a couple of months ago and I already have a Cloudless Sulfur caterpillar eating the yellow flowers (the caterpillar is a beautiful yellow). I have raised Swallowtails and Monarchs in my lanai inside a butterfly net. What can I feed this guy to keep him inside?


Leave a Comment