Plaster bagworm

Indoor walls, ceilings, and under furniture in warm, humid climates.

Feeds on spider webs, dust, hair, shed skin, and occasionally wool or cotton fabrics.

Larvae construct a flattened, case-like cocoon from silk and debris, dragging it along surfaces as they move.

Harmless to humans, though their cases cause cosmetic nuisance on walls and they can occasionally damage natural fibers.