(G. L. Godfrey, Illinois Natural History Survey, University of Illinois. Photos by M. E. Rice, Iowa State University, except Figure G by Douglas W. Tallamy, Department of Entomology and Applied Ecology, University of Delaware)

Several species of caterpillars (larvae) commonly found in the southern and western portions of the north central states are sometimes misidentified as the European corn borer. Occasionally, these caterpillars are found in the northern portion of the north central states. A pictorial key was developed for field identification. It illustrates the important characteristics of the caterpillars.

What does your caterpillar look like? Choose one of the following:

• Prolegs on abdominal segments 3, 4, 5, 6, and 10 (anal) (Figure A, below); go to step 2
• Fully developed prolegs present only on abdominal segments 5, 6, and 10 (Figure B, below), or on 6 and 10 (Figure C, below). Your species is most likely a Loopers

Simple pictorial key for identifying some common late-instar caterpillars found on corn.