Plaster Bagworm (or Household Casebearer)

Natural Habitat

Commonly found indoors on walls, ceilings, and in corners of garages, closets, and underneath spiderwebs. They thrive in high-humidity environments.

Diet & Feeding

Larvae feed on spider webs, old insect skins, wool, animal hair (including pet fur), dust, and debris. They do not generally eat plaster, despite the name.

Behavior Patterns

The larva constructs a flat, pumpkin-seed-shaped protective case out of silk and debris (like sand, soil, and insect parts), which it drags along with it. It retreats inside the case when threatened. They eventually pupate inside this case.

Risks & Benefits

Generally harmless to humans and pets (they do not bite or sting). However, they can be a minor nuisance pest in households due to their unsightly cases on walls and potential to feed on wool or natural fibers, though typically not as destructive as clothes moths.

Identified on: 2/7/2026