Household Casebearer or Plaster Bagworm

Natural Habitat

Typically found indoors in high-humidity areas, often seen on walls, in dusty corners, closets, or underneath furniture. They construct silken cases often covered with sand, soil, or debris.

Diet & Feeding

They feed on old spider webs, wool, hair, and other keratin-containing fibers, as well as dead insects and general household dust.

Behavior Patterns

The larva lives inside a flattened, pumpkin-seed-shaped protective case which it drags around as it moves. It withdraws into the case when disturbed. They are often spotted climbing walls to find a pupation site.

Risks & Benefits

Generally harmless to humans (they do not bite or sting). However, they can be a minor nuisance pest in homes and may cause slight damage to woolens or silks if infestations are large, though they prefer spider webs and dust.

Identified on: 3/2/2026