Louse

Louse, any of several wingless parasitic insects of 2 orders, Mallophaga (bird lice or biting lice) and Anoplura (mammalian or sucking lice). With flattened bodies and broad, clearly segmented abdomens, lice are well adapted to moving between hair or feathers, and are usually host-specific. Bird lice feed by chewing on feather fragments or dead skin, occasionally biting through the skin for blood. Mammalian lice feed purely on blood obtained with needlelike sucking mouthparts. The human lice spread several diseases.