Saddleback Caterpillar (Acharia stimulea) with Wasp Cocoons
© Thomas A. Hermann
Scientific Name(s): Acharia stimulea
Common Name(s): Saddleback caterpillar
Description: The saddleback caterpillar is about an inch long, has a purplish-brown body with a green saddle shape on its back, and has poisonous spines on four large projections (tubercles) and many smaller ones that stick out from the sides of its body. The poisonous spines are hollow and are connected to poison glands. Contact with them causes a burning sensation and inflammation that can be as painful as a bee sting. The “saddle” consists of an oval shaped, purplish-brown spot in the middle of a green patch on the back. Saddleback caterpillars feed on the leaves of basswood, chestnut, cherry, plum, oak, and other trees and shrubs. They are generally found in late summer. Note the white cocoons on the back of this caterpillar. These are braconid wasp cocoons. The braconid wasp larvae feed on the caterpillar from inside until they’re ready to emerge through small holes that they make.
(USA,Virginia, Springfield/ 09-1-2004 / Public Domain / (The National Biological Information Infrastructure (NBII) was terminated 15 January 2012.)