Plaster Bagworm

Scientific Name: Phereoeca uterella

Order & Family: Order: Lepidoptera; Family: Tineidae

Size: Case is approximately 1/2 inch (13mm) long; larva inside is smaller.

Plaster Bagworm

Natural Habitat

Typically found indoors in high humidity environments, residing on walls, ceilings, and under furniture.

Diet & Feeding

Larvae consume natural fibers such as wool, silk, hair, and spider webs.

Behavior Patterns

The larva builds a protective silken case covered in dust and debris. It can pull its head out of either end of the symmetrical case to move or feed.

Risks & Benefits

They are considered household pests as they can damage clothing or fabrics made from natural fibers, but they pose no direct health risk to humans or pets.

Identified on: 5/23/2026