Booklice (or Barklice)

Scientific Name: Liposcelis spp. (most likely genus for indoor booklice)

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

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

Booklice (or Barklice)

Natural Habitat

Damp, humid environments. Commonly found indoors in basements, bathrooms, libraries, pantries, and on damp paper, old cardboard, or moldy surfaces.

Diet & Feeding

They feed on microscopic mold and mildew, fungi, grains, insect fragments, and starchy materials (like wallpaper paste and book bindings).

Behavior Patterns

They are wingless, soft-bodied insects that move in quick, jerky motions. They do not bite or sting. They thrive in high humidity and are often an indicator of moisture issues.

Risks & Benefits

Risks: Nuisance pest; can contaminate stored food (grains/flour) and damage books or wallpaper. May trigger allergies in some people. Benefit: Can indicate hidden mold or moisture problems in a structure.

Identified on: 2/9/2026