Pherecydes Casebearer Moth Larva (or Household Casebearer)
Scientific Name: Phereoeca uterella (sometimes referred to as Phereoeca allutella)
Order & Family: Order: Lepidoptera, Family: Tineidae
Size: Typically 7-13 mm (approx. 0.3 to 0.5 inches) in length
Natural Habitat
Commonly found in high-humidity indoor environments like homes (bathrooms, closets), garages, and under furniture. They attach to walls, baseboards, and carpets.
Diet & Feeding
Feed on old spider webs, silk, and general detritus. They may also consume natural fibers like wool or human hair if available.
Behavior Patterns
The larva constructs a distinctive flattened, spindle-shaped case made of silk and debris (sand, soil, fibers), open at both ends. It drags this case around as it moves and can turn 180 degrees inside it to feed from either end.
Risks & Benefits
Generally harmless to humans (no biting or stinging). They are considered a minor pest; while they can damage wool or biological specimens, they primarily feed on spider webs and floor dust, making them more of a nuisance than a severe threat.
Identified on: 2/14/2026