Booklouse (or Psocid)
Scientific Name: Liposcelis spp. (Common household genus)
Order & Family: Order: Psocodea (formerly Psocoptera), Family: Liposcelididae
Size: Very small, usually between 1 mm to 2 mm in length.
Natural Habitat
Typically found in areas with high humidity or dampness such as bathrooms, kitchens, basements, or window sills. They often hide in wall voids, dusty shelves, old books, or behind wallpaper.
Diet & Feeding
They feed on microscopic mold, fungi, yeasts, starch, and sometimes dead insect fragments or starchy glues found in book bindings (hence the name).
Behavior Patterns
Booklice are flightless and move in quick, jerky spurts. They do not bite humans or animals. They thrive in humid conditions where microscopic mold grows and are often an indicator of a moisture problem.
Risks & Benefits
Risks: They are a nuisance pest rather than a health threat; they can contaminate stored food products like grains or cereals. Benefits: They are harmless scavengers that help break down organic detritus, though their presence indoors is generally undesirable.
Identified on: 2/21/2026