Issue 7, June 8, 2015
Convict Caterpillar
Convict caterpillars have been found feeding heavily on daylily foliage in Metropolis in far southern Illinois. In previous years they have also decimated the foliage of surprise lilies in that area of the state. They also feed on spider lilies, narcissus, and amaryllis in the southeastern U.S., feeding not only on the foliage, but also on bulbs and rhizomes.
They are unlikely to be found very far north in Illinois because this is a tropical species that only rarely ventures very far north. They likely overwinter reliably only southern Florida and Texas in the U.S.
Convict caterpillars are banded black and white and grow to be about one-and-one-half inches long. They have orange legs, head, and last abdominal segment. The last abdominal segment is similar in appearance to the head, being about the same size, color, and dark markings, so it appears that they have heads at both ends of the body.
Convict caterpillar on sunrise lilies.
After feeding for several weeks, they pupate and emerge as moths with two inch wingspans called Spanish moths. These moths are very attractive with pink wings containing black and yellow markings. The thorax is covered with black hairs giving the appearance of a feathered boa.
Infestations can be controlled with an application of Bacillus thuringiensis kurstaki (Dipel, Thuricide), spinosad (Conserve), and labeled pyrethroid insecticides. (Phil Nixon)
Author:
Phil Nixon