The multicolored Asian lady beetle Harmonia axyridis , has become common throughout the United States and all of Iowa. It is well known for the annoying habit of accumulating on the sides of buildings and wandering indoors during the fall. Asian lady beetles are a beneficial biological control in trees during the summer, and in fields and gardens during the fall, but can be a severe household nuisance during late fall and winter. Wooded residential and industrial areas are especially prone to problems. The origins of the Asian lady beetles are not clear, although it appears the current pest species was not purposefully released in the United States or in Iowa.
Multicolored Asian Lady Beetle – Wisconsin Horticulture
This introduction was deemed unsuccessful. Since its introduction, it has spread throughout most of North America. Adult beetles are domed, and round to oval in shape like the typical lady beetle Fig. The name "multicolored" refers to the many color forms of the adult lady beetles. Coloration can vary between shades of yellow, orange, or red, with or without black spots present on the wing covers. This species can be recognized and distinguished from other lady beetles by the following characteristics: on the white pronotum the middle body segment between the head and abdomen there are several black markings, which tend to fuse into a regular to irregularly shaped "M" or "W" depending on your vantage point.
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Other beetles do not have this unique mark. On the left is the 7- spotted lady beetle a different species than MALB, which is on the right. These lady beetles seldom cause primary damage; however, they do take advantage of breaks in grape skins caused by other insects, animals, or diseases.