The

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Haematomyzus'' includes three species of

lice Louse (: lice) is the common name for any member of the infraorder Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera was previously recognized as an order, until a 2021 genetic study determined th ...

that differ so markedly from all other lice that the genus is placed in its own

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Haematomyzidae, itself

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

within the

parvorder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized ...

Rhynchophthirina (previously ranked as a superfamily). These unusual lice are

ectoparasites Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The en ...

elephant Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant ('' Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian elephant ('' Elephas maximus ...

s and

warthog ''Phacochoerus'' is a genus in the family Suidae, commonly known as warthogs (pronounced ''wart-hog''). They are pigs who live in open and semi-open habitats, even in quite arid regions, in sub-Saharan Africa. The two species were formerly cons ...

s. Their mouthparts are elongated to form a drill-like structure that allows them to penetrate the thick skin of their host.

Taxonomy

The three species, '' Haematomyzus elephantis'' (elephant louse), '' Haematomyzus hopkinsi'' (warthog louse) and '' Haematomyzus porci'' ( red river hog louse) belong to a single family, the Haematomyzidae, itself the only family within Rhynchophthirina. Rhychophthirina is a

within the

infraorder Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classific ...

Phthiraptera Louse (: lice) is the common name for any member of the infraorder Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera was previously recognized as an order, until a 2021 genetic study determined that ...

. A molecular phylogenetic study using subunit rRNA sequences suggests a placement of the Rhychophthirina as a

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of the

Anoplura Sucking lice (known scientifically as Anoplura) are a parvorder of around 550 species of lice. All sucking lice are blood-feeding ectoparasites of mammals. They can cause localized skin irritations and are vectors of several blood-borne diseas ...

. Below is a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

showing the position of Rhychophthirina within

Host records

''H. elephantis'' is known from both the African and Asian Elephant in captivity but the species found in the wild are thought to have coevolved with their hosts and further study is required.

Notes

The first spelling of "Rhyncophthirina" by Ferris was a lapse, and in subsequent use of the term he spelled it "Rhynchophthirina" adding the second "h". Ordinal names are not covered by the International Code of Nomenclature and thus the name and spelling comes down to a matter of personal preference. The majority of phthirapterists spell the suborder as "Rhynchophthirina" as did Hopkins and Clay, 1952, and Price ''et al.'', 2003.

References

* * Lice Insect genera Insects of Africa Insects of Asia {{Parasite-insect-stub