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The (Multicolored) Asian Lady Beetle
Harmonia axyridis (Pallas)

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G. Keith Douce, Professor of Entomology, The University of Georgia

Order Coleoptera: Family Coccinellidae

Background: Lady beetles are predators that feed on other insects as both larvae and adults. There are more than 450 known lady beetle species in North America. A number of exotic lady beetles have been purposely released in the U.S. as biological control agents for control of selected insect pests. The non-native H. axyridis lives primarily in trees and prays mostly on aphids. It is highly prolific, may live up to three years and exhibits several color forms (is polymorphic). Between 1916 and the mid-1970's, there were several U.S. introductions of H. axyridis made with no apparent survival. The beetle did, however, become established after a series of releases made in the late 1970's and early 1980's by U.S.D.A. Agricultural Research Service scientists in Byron GA and in other U.S. locations. Since those releases, the beetle has rapidly expanded its range and is now commonly found throughout much of the U.S.


Asian Lady Beetle Larva

Released Beetles

Established Beetles

Evidence: Adult H. axyridis are about 1/4 inch long. Adult wing covers range from black-to-mustard in color with the number of spots present ranging from zero up to 20. The most common U.S. form is mustard-to-red with 16 or more black spots. A key identification feature is the presence of big false "eyes" — twin white football-shaped markings behind the head. Females lay from 500-700 eggs each. Larvae exhibit the typical alligator-shape of other lady beetle larvae, and are black with an orange streak on both sides of their abdomen. There are several generations per year.

Impact: The Asian lady beetle is an extremely benefical predator of aphids on pecans and other trees as well as on a number of other crops. However, overwintering adults tend to aggregate in large numbers in the fall to locate suitable protected overwintering sites. Clusters of adults are frequently found in "swarms" on many outdoor objects, including light-colored rock outcroppings, doors, windows, walls and porches of buildings. Unfortunately, if there are cracks and crevices in buildings large enough for them to crawl through, the beetles will migrate inside where they can become a nuisance.

Since the beetles are benefical in controlling other insects and cause no direct harm to people or their belongings, it is preferable to avoid killing them if possible. Prevent their entry into homes by installing tight screens and sealing cracks and crevices around doors, windows, siding and utility pipes. If adults gain entry, remove them with a broom and dust pan or the vacuum cleaner with the crevice tool attachment. Care should be used when handling the beetles ... they emit a smelly orange colored defensive fluid from leg joints that can stain walls and fabrics, although it is not harmful to humans. Contact your local county extension office for more information.

For More Information:

Lady Beetle Traps from H&T Alternative Controls, LLC

B. Sparks, W.L. Tedders. 1996. Lady Beetles: Friend or Foe. Flyer 96-56. The Univ. of GA, Col. Agr. and Envir. Sci., Coop. Ext. Serv., Athens GA. http://www.forestpests.org/misc/ldybttles/ldybttles.html

Unofficial Homepage of the Asian Ladybird Beetle. http://home.ptd.net/~insect/ladybug.html .

S. Mahr. Know your friends: Multicolored Asian lady beetle. Midwest Biological Control News. http://www.entomology.wisc.edu/mbcn/kyf210.html

Photo Credits: W. Louis Tedders, Jr. USDA ARS SE Fruit and Tree Nut Laboratory, Byron GA 31008, and Beneficial Insectry, 14751 Oak Run Road, Oak Run, CA 96069.

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Page last modified: Monday, April 29, 2002
Questions and/or comments to: bugwood@uga.edu