Twice-stabbed Lady Beetle © Jason Michael Crockwell

Twice-stabbed Lady Beetle © Tom Murray

Twice-stabbed Lady Beetle © Tom Murray

The Twice-stabbed Lady Beetle is native to the U.S. and Canada. It has two red spots on its wing covers and a solid black body. It lives primarily in forested habitats and feeds on aphids and other pests, making it an important species in both natural and commercial forests. This species overwinters in leaf litter.

Status

Native

The Twice-stabbed Lady Beetle has not been ranked in the United States. It is listed as Vulnerable in Nova Scotia, Saskatchewan, and Alberta; and ranked as Apparently Secure in Ontario and New Brunswick.

Last Seen

2020

Fun Fact

The Twice-stabbed Lady Beetle is showing some success at controlling the Elongate Hemlock Scale (Fiorinia externa Ferris), a species damaging North American hemlock trees.

Identification

The Twice-stabbed Lady Beetle is 3 to 5 mm in length.

Habitat

Forests. Adult Twice-stabbed Lady Beetles have been found on vegetation and trunks of trees infested with scale insects, mealybugs, and aphids. Since the introduction of Beech Bark Disease, Twice-stabbed Lady Beetles have been associated with heavily infested beech trees.

General Range

Found across most of North America, excluding the west coast.

Food

Primarily eats scale insects, such as Beech Bark Scale. Will also eat adelgids, aphids, and other soft-bodied insects.

Life Cycle

Twice-stabbed Lady Beetles overwinter in leaf litter. They have been found to be active from early March through November in Vermont. One study in New York found that Twice-stabbed Lady Beetles mate from April to May, and lay their eggs in cracks or under loose bark of trees infested with scale insects. Adults seem to be most numerous from late June to early August. It appears that local populations of Twice-stabbed Lady Beetles have slightly different numbers of generations based on temperature and prey life cycles–it appears that Twice-stabbed Lady Beetles closely synchronize their life cycle with that of the most abundant prey in their region.

More Information

You can find more information about Twice-stabbed Lady Beetles using the following links:

Vermont Distribution

Visit the iNaturalist Observation Map or the Occurrence Record to find out where Twice-stabbed Lady Beetles have been seen in Vermont.