Household Casebearer or Plaster Bagworm

Natural Habitat

Commonly found indoors on plastered walls, in garages, under eaves, and in humid environments. They prefer high humidity and are often seen in closets or on wool rugs.

Diet & Feeding

Detritivores; larvae feed on spider webs, old insect skins, woolen fibers, human hair, dust, and microscopic debris found in homes.

Behavior Patterns

The most distinctive behavior is the larva carrying a flat, pumpkin-seed-shaped case made of silk and debris (sand, insect parts, fibers). The larva stays inside this protective case and drags it along surfaces, emerging from either end to feed. They eventually pupate inside the same case.

Risks & Benefits

Generally harmless to human health (they do not bite or sting). They can be a minor pest nuisance as they feed on natural fibers like wool and silk, potentially damaging clothing or rugs, though they are less destructive than webbing clothes moths. They can be beneficial by cleaning up minor debris like old spider webs.

Identified on: 2/25/2026