Household Casebearer (Plaster Bagworm larva)
Scientific Name: Phereoeca uterella
Order & Family: Lepidoptera: Tineidae
Size: Case typically 8-14 mm in length; larva itself is smaller.
Natural Habitat
Indoor environments, found on walls, floors, and in closets, especially in humid or tropical climates.
Diet & Feeding
Larvae feed on spider webs, woollen fabrics, silk, and human hair shed in the home.
Behavior Patterns
The larva constructs a protective spindle-shaped case from silk, sand, and dust. It can poke its head out from either end to move or feed.
Risks & Benefits
Cosmetic household pest; can occasionally damage silk or wool items. While they don't bite humans, their presence often indicates high indoor humidity or excessive dust/spider webs.
Identified on: 1/15/2026