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University of Minnesota Extension

Extension > Garden > Diagnose a problem > What insect is this? > Insects found indoors > Beetles, bugs, ants, and other insects without obvious wings - Under 1/4 inch long > Book louse

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Book louse

Book louse

Jeff Hahn, University of Minnesota Extension

Book louse

Ken Gray Collection, Oregon State University

Description: Up to 3/16 inch long

Where/When: Found outdoors, on tree bark, plant foliage, or under stones. Found indoors in damp, warm, undisturbed places where mold and fungi are growing, especially during spring and summer.

Significance: Nuisance. They are harmless to people and essentially harmless to property; on rare occasion, they can damage some paper products.

More information on Book lice

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