Phereoeca uterella or Tinea pellionella (Plaster Bagworm or Case-bearing Clothes Moth Larva)

Natural Habitat

Found indoors in homes, typically on walls, baseboards, carpets, and inside closets. They thrive in dark, undisturbed areas with high humidity.

Diet & Feeding

The larvae feed on keratin-rich materials such as wool, silk, hair, pet fur, feathers, and spider webs. They may also eat dried insects and general household dust/lint.

Behavior Patterns

The larva constructs a protective, flattened, pumpkin-seed-shaped case out of silk and debris (sand, soil, lint) which it carries around as it feeds. It can turn around inside the case to feed from either end. When ready to pupate, it attaches the case to a vertical surface like a wall.

Risks & Benefits

Risks: Considered a household pest because they can damage natural fiber clothing, rugs, and upholstery. They generally do not bite or sting humans. Benefits: They act as detritivores by cleaning up spider webs and dead insects, though this benefit is usually outweighed by their pest status.

Identified on: 3/6/2026