Plaster Bagworm (or Household Casebearer)
Scientific Name: Phereoeca uterella
Order & Family: Order: Lepidoptera, Family: Tineidae (Clothes Moths)
Size: Larval case is roughly 8 to l3 mm (0.3 to 0.5 inches) in length.
Natural Habitat
Typically found in tropical and subtropical climates inside homes, particularly in high-humidity areas, on walls, baseboards, and in dark corners like closets or attics.
Diet & Feeding
Detritivores that feed on old spider webs, book bindings, wool, hair, lint, dead insects, and other organic debris found in dust.
Behavior Patterns
The larva constructs a silky, flattened, pumpkin-seed-shaped protective case which it drags around with it. It has openings at both ends allowing the larva to feed and move from either side. They eventually pupate inside this case.
Risks & Benefits
Risks: Generally harmless to humans (they do not bite or sting) but can be a nuisance pest. They may cause minor damage to woolen fabrics or rugs if populations are high. Benefits: None significant, other than consuming small amounts of household debris.
Identified on: 2/22/2026