The genus Haematomyzus includes three species of lice that differ so markedly from all other lice that the genus is placed in its own family Haematomyzidae, itself monotypic within the superfamily Rhynchophthirina. These unusual lice are ectoparasites of elephants and warthogs. Their mouthparts are elongated to form a drill-like structure that allows them to penetrate the thick skin of their host.

Louse is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result of developments in phylogenetic research.