Booklouse (psocid), likely a barklouse

Damp indoor areas, stored paper, books, cardboard, and undisturbed surfaces; also found outdoors on bark and leaf litter.

Feeds mainly on microscopic mold, fungi, algae, and organic debris rather than biting people or damaging sound materials.

Small, soft-bodied, and often wingless; thrives in humidity and may increase where condensation or mold is present. It moves slowly and is easily disturbed.

Harmless to humans and does not transmit disease or infest skin. Large indoor numbers indicate excess moisture; reducing humidity and cleaning mold usually controls them.