Booklice & Barklice (Psocoptera)

Greek "psokos" (rubbed, knawed) + "ptera" (wings)
Barklice are a little less than half an inch long, and usually have 2 pairs of wings. They live in moist forest conditions, often in colonies protected by silk coverings they spin. They eat algae, lichens, fungi and other plants. Booklice are wingless and much smaller that barklice, and are commonly found in houses and other buildings, feeding on grain, or starchy products such as wallpaper paste and fabric sizing. Some live in bird nests, eating discarded feathers and skin cells.

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Booklice, on nutritional yeast
© 2006 Joyce Gross
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Booklice and eggs, on nutritional yeast
© 2006 Joyce Gross

Quick ID

  • Booklice: no wings, found indoors
  • Barklice: wings, found in the woods
  • Small, a fraction of an inch long
  • Distinct head, with thread-like antennae
  • Narrow "neck" between head & thorax

More information about Psocoptera

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Last updated: Jan 3, 2017