Pthirus

Pthirus is a genus of lice. There are only two extant species, and they are the sole known members of the family Pthiridae.^[4] Pthirus gorillae infests gorillas,^[5] and Pthirus pubis afflicts humans, and is commonly known as the crab louse or pubic louse.^[6] The two species diverged some 3.3 million years ago.^[7]

Pthirus
Pthirus gorillae
Pthirus pubis
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Psocodea
Suborder:	Troctomorpha
Infraorder:	Phthiraptera
Parvorder:	Anoplura
Family:	Pthiridae Ewing, 1929
Genus:	Pthirus Leach, 1815[1]
Type species
Pediculus pubis[2] Linnaeus, 1758
Species
P. gorillae Ewing, 1927 P. pubis (Linnaeus, 1758)
Synonyms
Phthirus Leach, 1817[3]

Since 1958 the generic name Pthirus has been spelled with pth rather than phth, despite this being based on a misspelling of the Greek-derived phthirus.^[3][8]