Cycnia inopinatus Caterpillars

I’m always pleased when an uncommon plant or animal species shows up in unusually large numbers. This year, I am finding the caterpillars of the Unexpected Tiger Moth, Cycnia inopinatus, to be several times more abundant than they have ever been in any past year. Having a bright orange body decorated with tufts of black hairs, this species is hard to miss when it’s around.

The Unexpected Tiger moth is listed as an endangered species in the state of Ohio. Its caterpillars feed exclusively on milkweeds, with Butterflyweed, Asclepias tuberosa, probably being the most common host plant. So far this year, I’ve found caterpillars on Butterflyweeds scattered over about a 30 acre area.

In late spring and early summer I’ve seen the caterpillars feeding on Spider Milkweed, Asclepias viridis. Recently, I’ve found several caterpillars feeding on the leaves of Common Milkweed, Asclepias syriaca.

A five-year-old clump of Butterflyweed growing next to my driveway is currently hosting a half dozen caterpillars. Later this year the caterpillars will move into the leaf litter at the base of the plant and pupate. They will remain there through the winter and emerge as adults next spring.

The Common Milkweed being used as a host plant is growing at the edge of my water garden. So far, this is the only Common Milkweed plant that I have found hosting any Unexpected Tiger Moth caterpillars.

Oleander Aphids have been abundant on all of the milkweeds this year. Caterpillars seem to avoid leaves that are excessively covered with aphids and honeydew, but there are enough clean leaves that the caterpillars do not seem to be lacking an adequate food supply. I hope this abundance of caterpillars results in record numbers of adult moths next spring.

The above video shows some of the typical caterpillar activities.