This is a family of flightless lice that are parasitic on mammals. In contrast to the related Pediculidae (with the human body louse), the Trichodectidae are not blood-sucking but have chewing mouthparts. The members are parasitic on domestic animals and wild mammals. They are attached to hairs and also cement their eggs to the hairs, feeding mainly on the outer keratin layer of the skin and on skin secretions. Some species may damage the skin. The insects are flat, usually 1-2 mm long. They move to another host during body contact. Some genera like Bovicola are sometimes assigned to a separate family, the Bovicoliidae.
The following species are currently entered under Pediculidae: