Setae (hairs) on the dorsal side of European corn borer larvae are encircled by a darker-colored “halo� or ring. This is a distinguishing characteristic with this insect in separating it from other corn attacking caterpillars.

Late-stage European corn borers showing dark and light color phases.

A fifth-stage European corn borer on ornamental Indian corn. Note that this larva is a lighter color phase and shows a reddish brown head.

The European corn borer also attacks ornamental varieties of corn. This fifth-stage larva is shown on Indian corn.

A late-stage European corn borer larva on Indian corn.

A fifth-stage larva on a commercial dent corn ear.

A fifth-stage larva on a commercial dent corn ear. Note that the head is not completely black, as is common in many individuals, but has reddish brown stripes.

A fifth-stage larva on a commercial dent corn ear. Note that the head is completely black and the body is dark gray or brown in color.

A full-grown, fifth-stage larva is nearly 1 1/2 times the length of a dime.

European corn borers develop through five larval stages. A distinguishing feature is that the larva in each stage has a dark head, often black or reddish brown in color. The prothoracic shield (neck) may or may not be dark.