Lady beetles are common throughout the United States and many species are native and biologically important. The multicolored Asian lady beetle, an introduced species, is a large species among its kind. Adults can be up to 1/4 inch long and are quite round. The color of this species varies greatly, from lighter orange with no spots to dark red with heavy, overlapping spots. There is a W-shaped marking in black on the white pronotum. Larvae are a spiny-looking combination of red and black and can be as much as 1/2 inch long with prominent legs.

Female lady beetles lay their eggs in clusters on plants near a larval food source, such as aphids. Both larvae and adults feed on small, soft-bodied insect prey and are therefore beneficial insects. The life cycle from egg to adult is about 1 month long in good conditions. Asian lady beetles overwinter as adults in aggregations. Beetles may live for as long as 2 or 3 years.

In their native China, multicolored Asian lady beetles are attracted to crevices in cliffs and mountains for protection from winter weather. In Pennsylvania, these beetles commonly seek shelter on or inside buildings in September and October, and they may enter in huge numbers. There may be a preference for taller and light-colored buildings and the south-and west-facing sides. Although they cause no structural damage and do not lay eggs inside buildings, large numbers of beetles can be an asthma trigger and/or nuisance. When bothered or crushed, they release a yellow liquid, which will stain. These invasive lady beetles are thought to be outcompeting native species.