Booklouse (or Psocid)

Scientific Name: Liposcelis spp. (Commonly Liposcelis bostrychophila)

Order & Family: Order: Psocodea (formerly Psocoptera), Family: Liposcelididae

Size: Very small, typically 1 mm to 2 mm in length.

Booklouse (or Psocid)

Natural Habitat

Found in warm, damp indoor environments including bookshelves, pantries, closets, and bathrooms; often hides in cracks, crevices, stored dry foods, and paper products.

Diet & Feeding

Feeds on microscopic molds, fungi, starch, glue (like bookbinding glue), and stored food products such as flour or grains.

Behavior Patterns

They are wingless, soft-bodied insects that run quickly rather than fly. They do not bite but reproduce rapidly via parthenogenesis in warm, humid conditions.

Risks & Benefits

Generally harmless to humans and pets as they do not bite or transmit disease. However, they can contaminate stored food products and, in large numbers, indicate a moisture or mold problem in the home.

Identified on: 2/10/2026