The Psocoptera are tiny insects with chewing mouthparts that have either four wings or none. Why the name 'chewing wing' was assigned is unknown and is one of the few names that do not add usefulness to the taxonomy of insects. Psocopteran metamorphosis is gradual. They are often called psocids (pronounced so-sids) and may be separated from psyllids and aphids based on their enlarged clypeus and chewing mouthparts. They live outdoors and are found resting on stones, logs, and fences. Some of the wingless Psocoptera are called booklice and are found around old books and papers and in damp, dark rooms. They feed on molds, fungi, and pollen and may build up to very high nuisance populations if left unchecked.
