Structure, Appearance and Characteristics
Psocids or Book Lice (also known as known as Paper Lice, can often be found crawling in large numbers over stored papers, books, walls, furniture, and other materials in damp, warm, undisturbed areas in buildings especially during the spring and summer months. They can be readily introduced into a new habitat on furniture, boxes, books and paper.
They feed on microscopic mould and mildew associated with high-humidity conditions. Outdoor species are also known as Barklice since they are found under tree bark or leaves.
They can be found on walls, in cupboards, in stored foodstuffs, in wall voids and behind electrical power outlets.
Psocids do not bite humans or animals, spread disease, or damage household furnishings. However, skin irritation may occur on sensitive individuals and some animals. Psocids are less than 1 mm – 10 mm in length, but Booklice are less than 5 mm in length. They most active during daylight hours. Females are wingless, whereas males have two clear membranous pair of wings. They have a large head, a flattened body with medium to long thread like antennae that is often at least half their body length and six, short stocky legs. They have chewing mouthparts and the mouthparts are held downwards when at rest.
Colouring ranges from almost colourless through grey to light brown, and the young are almost colourless.