Household Casebearer (also known as the Plaster Bagworm)

Natural Habitat

Typically found indoors in dry, dusty environments. Common on walls (especially stucco or plaster), baseboards, underneath furniture, and inside closets or garages where they attach to fiber.

Diet & Feeding

Feeds on keratin-rich debris, including spider webs, old insect skins (exuviae), human hair, pet fur, wool, and dead insects.

Behavior Patterns

The larva constructs a flat, pumpkin-seed-shaped protective case out of silk and surrounding debris (sand, dust, lint). It carries this case with it as it moves. The larva can extend its head and legs from either end of the case to crawl.

Risks & Benefits

Risks: Generally considered a nuisance pest rather than a danger. They do not bite or sting. However, in large numbers, they can damage fabrics like wool or silk. Benefits: They clean up minor debris and old spider webs in the home.

Identified on: 3/3/2026