Common Name: Lady beetle
Scientific Name: Coccinellidae: spp
Status: A very beneficial insect but an annoying household invader
Damaging Stage: Adult and larva

Biology: Lady beetles are small, round, and dome-shaped. The most well known lady beetles have black markings on red, orange, or yellow forewings, but some are black. Lady beetle larvae can grow to approximately 3/8 inches in length. They are usually black with orange spots, covered with spines and somewhat resemble tiny alligators with three pairs of legs.

In the spring, overwintering adults find food and the females lay their eggs, often near aphid colonies. The eggs hatch in three to five days and the larvae feed on aphids or other small insects. After two to three weeks, they pupate. Adults emerge within a week. There may be five to six generations per year.

Injury: Larvae feed on aphids, soft-scale insects, mealybugs, spider mites and other pests. One mature lady beetle larvae can eat its weight in aphids (approximately 400 aphids) in one day.

Action Threshold: Lady beetles are beneficial insects and are only an annoyance when they appear in large numbers in the home. One species of lady beetle (Multicolored Asian Lady beetle) has a peculiar behavior of congregating and passing the winter in man-made structures. This causes significant annoyance to homeowners and, may become a health problem.

Management: Cultural controls (sealing entry points in the fall and and vacuuming emerging beetles) are effective against low populations populations. Chemically treating on the outside of the home can also decrease beetle populations during extreme infestations.