Multicolored Asian Lady Beetle (Harmonia axyridis)
Reviewed and updated by Daniel Frank, WVU Extension Service Entomology Specialist, September 2013
The multicolored Asian lady beetle (Harmonia axyridis) is native to Asia, but has become common throughout much of the United States. The beetle has entered into the country through a number of accidental and planned releases. Federal, state, and private entomologists have released the insect at a number of locations throughout the United States in an attempt to naturally control insect pests in trees. There are also several reports of accidental entries from international cargo ships arriving at various port cities, notably New Orleans.
The multicolored Asian lady beetle occurs in many color combinations. Adult beetles are oval and convex, about 6 mm long and 5 mm wide. North American populations have a mix of individuals ranging in color from pale yellow-orange to bright red-orange, with or without black spots on the wing covers. The pronotum (top covering of middle body part) is white to straw-yellow with several black spots joined to form two curved lines, an M-shaped mark, or a solid trapezoid.
Outdoors during the growing season, multicolored Asian lady beetles are quite beneficial as predators of aphids and other soft-bodied insects associated with trees, shrubs, ornamental plants, and some agricultural crops.
The beetles are attracted to houses with light-colored exteriors, such as white or yellow, and will often congregate in areas exposed to afternoon sun. Although they will not cause structural damages to houses like termites, they emit an unpleasant odor and can stain walls and fabrics if agitated or crushed.
Lady beetles can cause allergies and skin irritations in some people, but are not poisonous or otherwise harmful to humans, pets or property. The beetles do not carry disease, but can bite in rare cases.
- Asian Lady Beetles
- Observation of Cosmetic Damage on a House Caused by the Multicolored Asian Lady Beetle, Harmonia axyridis (Coleoptera: Coccinellidae) Unpublished report by T.W. McCutcheon and H. R. Scott