Mexican Bean Beetle, Epilachna varivestris Mulsant (Coleoptera: Coccinellidae)

Mexican bean beetle is native to Mexico and Central America. By the 1800s it was damaging to beans throughout the southwestern United States, wherever beans were cultivated. A major increase in damage followed the accidental transport of Mexican bean beetle to the eastern United States, to northern Alabama about 1918, apparently in shipments of alfalfa hay from Colorado and New Mexico. The beetle, once gaining access to eastern states, spread rapidly to the northeast, and is now found throughout much of the United States and eastern Canada.

Host Plants

Mexican bean beetle develops only on legumes. Other plants are occasionally reported injured. Vegetable crops eaten are cowpea, lima bean, and snap bean, particularly the latter two bean types. Related crops such as faba bean, lentil, and mung bean seem to be immune. Field crops that may be attacked include alfalfa, sweet clover, various dry beans, and soybean. Formerly the field crops other than dry beans were relatively unsuitable and...