Phereoeca uterella (often called the Plaster Bagworm or Household Casebearer)

Natural Habitat

Typically found indoors, clinging to walls, baseboards, underneath furniture, or in closets. They thrive in environments with high humidity, often seen in garages or bathrooms.

Diet & Feeding

Larvae feed on silk, spider webs (even old ones), wool, lint, animal fur, and human hair.

Behavior Patterns

The larva constructs a distinctive flat, pumpkin-seed-shaped protective case made of silk and debris (sand, soil, frass). It drags this case along as it moves. The moth eventually pupates inside the case. They are attracted to light.

Risks & Benefits

Risks: Generally considered a nuisance pest rather than dangerous. They do not bite or sting, but can damage woolen fabrics, rugs, or clothing if an infestation is large. Benefits: Minimal, they help clean up old spider webs and dust bunnies, though usually unwanted in homes.

Identified on: 2/11/2026