Potato Beetle, any of three species of yellow, striped beetles that prey on the potato plant. The Colorado potato beetle is the most destructive. It is a round beetle, less than one-half inch (13 mm) long, with 10 black stripes down its back. Adults and the reddish, soft-bodied larvae, popularly called “slugs,” feed on potato leaves and also attack tomato and eggplant foliage. The Colorado potato beetle is native to the eastern slopes of the Rocky Mountains. It spread eastward in the 1850's, causing much damage. Control with Paris green began in the 1870's; today, other insecticides are also used.

The Colorado potato beetleThe Colorado potato beetle can be quite destructive to crops.

Two species of beetles, native to the eastern United States, are called old-fashioned potato beetles (or bugs)because they were familiar to farmers long before the Colorado potato beetle arrived. Both are narrow-bodied. One is three-fourths of an inch (2 cm) long, with four stripes; the other is one-fourth inch (6 mm) long, with three stripes.

The Colorado potato beetle is Leptinotarsadecemlineata of the leaf beetle family, Chrysomelidae. The larger of the old-fashioned potato beetles is Epicauta vittata of the blister beetle family, Meloidae; the smaller is Lema trilineata of the family Chrysomelidae.