PSOCID

any member of the insect order Psocoptera (also called Corrodentia), of about 1,100 species. The psocid is soft-bodied and usually less than 5 mm (0.2 inch) long. Its slender antennae are at least as long as its body, and wing venation is simple (there are no crossveins). Mouthparts are adapted for chewing, with the upper jaw usually elongated and chisellike. Psocids eat fungi (including molds), cereals, pollen, and organic debris. The best-known species, the booklouse, is a pale and wingless insect usually found indoors among old books and papers, on dusty shelves, or in cereals. The majority of psocids, usually called barklice, generally have four membranous wings that are held rooflike over the body when at rest. They are found on tree bark and foliage, under stones, or in ground litter.