Harmonia axyridis

Taxonomy

Domain	Eukarya
Kingdom	Animalia
Phylum	Arthropoda
Subphylum	Hexapoda
Class	Insecta
Subclass	Pterygota
Infraclass	Neoptera
Order	Coleoptera
Suborder	Polyphaga
Infraorder	Cucujiformia
Superfamily	Coccinelloidea
Family	Coccinellidae
Subfamily	Coccinellinae
Tribe	Coccinellini
Genus	Harmonia

Scientific Name

Harmonia axyridis

Common Name

multicolored Asian lady beetle

Description

These insects are generally called ladybugs or lady beetles. Lady beetles are predators as both a larva and adult. Like all insects, lady beetles have three body regions; a head, thorax and abdomen. To identify species, examine characters on both the pronotum, a plate that covers the thorax, and the wing covers, which protect the abdomen, for spot and color patterns.

Distinctive Features

Adults: Round. Many color forms exist, ranging from yellow to red. Diagnostic feature is a white pronotum with a black M or W pattern depending on the viewing direction. May or may not have black spots on wing covers. This is the species that aggregates in homes during winter. Larva: Alligator-like, long and slender. Black in color with orange flexible spines.

Life Cycle

Female beetles lay 15-25 yellow oval eggs in clusters on leaves or stems. Eggs hatch within 3-5 days into a larva. Larvae molt four times before they pupate on plant leaves or stems. The adult emerges from the pupa after 1-2 weeks. The full development time from egg to adult requires 15-25 days. This beetle species overwinters as an adult in buidlings or protected outdoor areas such as treelines, fencerows, and leaf litter.

Prey

Aphids, beetle larvae, caterpillars, insect eggs, other soft-bodied insects.

Habitat

Can be found on leaves, stems, and flowers; in backyard gardens, crop fields, meadows, and woodlands.This lady beetle is commonly found invading homes, offices, and other buildings in the fall in an effort to escape the impending harsh winter conditions.

Floral Resources

This lady beetle can feed on pollen and nectar in addition to insect prey.

Distribution

Found in most states throughout North America.

Origin

Exotic.

Occurrence

Very Common.

Size

7-8 mm.

Color

Red, orange, yellow, black.

As a Biological Control

The multicolored Asian lady beetle, Harmonia axyridis, is a species that was purposefully introduced into North America and has now become widely distributed. It is a fairly large species with highly variable markings and is a voracious predator of aphids, particularly on shade trees. However, it has the somewhat unfortunate habit of often wintering in homes, where it may be a nuisance problem. They go into dormancy (diapause) when day length becomes less than 16 hours.