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.
Sucking lice have around 500 species and represent the smaller of the two traditional superfamilies of lice. As opposed to the paraphyletic chewing lice, which are now divided among three suborders, the sucking lice are monophyletic.
The Amblycera are a large clade of chewing lice, parasitic on both birds and mammals. The Amblycera are considered the most primitive clade of lice.
Psocoptera are a paraphyletic group of insects that are commonly known as booklice, barklice or barkflies. The name Psocoptera has been replaced with Psocodea in recent literature, with the inclusion of the former order Phthiraptera into Psocodea.
A bird louse is any chewing louse of order Phthiraptera which parasitizes warm-blooded animals, especially birds. Bird lice may feed on feathers, skin, or blood. They have no wings, and their biting mouth parts distinguish them from true lice, which suck blood.
Psocomorpha is a suborder of barklice, booklice, and parasitic lice in the order Psocodea. There are more than 20 families and 5,300 described species in Psocomorpha.
Trogiomorpha is one of the three major suborders of barklice, booklice, and parasitic lice in the order Psocodea, alongside Troctomorpha and Psocomorpha. There are about 8 families and more than 430 described species in Trogiomorpha. Trogiomorpha is widely agreed to be the earliest diverging of the three suborders, and retains the most primitive characteristics.
Troctomorpha is one of the three major suborders of Psocodea (barklice, booklice, and parasitic lice), alongside Psocomorpha and Trogiomorpha. There are more than 30 families and 5,800 described species in Troctomorpha. The order includes parasitic lice, which are most closely related to the booklice family Liposcelididae.
The Philopteridae are a family of Ischnocera, chewing lice mostly parasitic on birds.
Ectopsocidae is a family of Psocodea belonging to the suborder Psocomorpha. The family includes fewer than 200 species, most of them in the genus Ectopsocus.
Homilopscocidea is an infraorder of Psocodea. It is probably a paraphyletic group, still in use for lack of a better solution. There are about 7 families and more than 1,200 described species in Homilopsocidea.
Psocodea is a taxonomic group of insects comprising the bark lice, book lice and parasitic lice. It was formerly considered a superorder, but is now generally considered by entomologists as an order. Despite the greatly differing appearance of parasitic lice (Phthiraptera), they are believed to have evolved from within the former order Psocoptera, which contained the bark lice and book lice, now found to be paraphyletic. They are often regarded as the most primitive of the hemipteroids. Psocodea contains around 11,000 species, divided among four suborders and more than 70 families. They range in size from 1–10 millimetres (0.04–0.4 in) in length.
Paraneoptera or Acercaria is a superorder of insects which includes lice, thrips, and hemipterans, the true bugs. It also includes the extinct order Permopsocida, known from fossils dating from the Early Permian to the mid-Cretaceous.
The Ricinidae are a family of a larger group Amblycera of the chewing lice. Most commonly they are ectoparasites of birds. The family includes the genus Ricinus.
Campanulotes elegans is a species of lice in the disputed, probably paraphyletic, family Philopteridae, the chewing lice, or in the family Goniodidae.
Rallicola is a genus of chewing louse. It is an ectoparasite of rails and other birds. It was named by Thomas Harvey Johnston and Launcelot Harrison in 1911. There are two subgenera aside from the nominotypical subgenus: Aptericola, whose species are found on kiwi birds, and Huiacola, a monospecific subgenus consisting of Rallicola extinctus, once found on the huia.
Trichodectidae is a family of louse in the suborder Ischnocera. Its species are parasites of mammals. The following 19 genera are recognized:
Geomydoecus is a genus of louse in the suborder Ischnocera. They are parasites of gophers (Geomyidae). Species include:
Harrison's rule is an observation in evolutionary biology by Launcelot Harrison which states that in comparisons across closely related species, host and parasite body sizes tend to covary positively.
Enderleinellidae is a family of parasitic lice in the order Psocodea. There are about 5 genera and more than 50 described species in Enderleinellidae.
