Tarsiiformes are a group of

primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians ( monkeys and apes, the latter including ...

s that once ranged across Europe, northern Africa, Asia, and North America, but whose extant

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

are all found in the islands of

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical south-eastern region of Asia, consisting of the regions that are situated south of mainlan ...

. Tarsiers (family Tarsiidae) are the only living members of the

infraorder Order ( la, ordo) 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 ...

; other members of Tarsiidae include the extinct ''

Tarsius eocaenus ''Tarsius'' is a genus of tarsiers, small primates native to islands of Southeast Asia. Until 2010, all tarsier species were typically assigned to this genus, but a revision of the family Tarsiidae restored the generic status of ''Cephalopachus' ...

'' from the

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

, and '' Tarsius thailandicus'' from the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

. Two extinct genera, '' Xanthorhysis'' and '' Afrotarsius'', are considered to be close relatives of the living tarsiers, and are generally classified within Tarsiiformes, with the former grouped within family Tarsiidae, and the latter listed as ''

incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertain ...

'' (undefined). Omomyids are generally considered to be extinct relatives, or even ancestors, of the living tarsiers, and are often classified within Tarsiiformes. Other fossil primates, including Microchoeridae, Carpolestidae,McKenna, M.C., and Bell, S.K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 337–340 pp. and Eosimiidae, have been included in this classification, although the fossil evidence is debated. Eosimiidae has also been classified under the infraorder

Simiiformes The simians, anthropoids, or higher primates are an infraorder (Simiiformes ) of primates containing all animals traditionally called monkeys and apes. More precisely, they consist of the parvorders New World monkeys (Platyrrhini) and Cata ...

(with monkeys and

ape Apes (collectively Hominoidea ) are a clade of Old World simians native to sub-Saharan Africa and Southeast Asia (though they were more widespread in Africa, most of Asia, and as well as Europe in prehistory), which together with its sister g ...

s), and most experts now consider Eosimiidae to be stem simians. Likewise, Carpolestidae is often classified within the order Plesiadapiformes, a very close, extinct relative of primates.Fleagle, J. G. 2013
Primate Adaptation and Evolution
San Diego, Academic Press. These conflicting classifications lie at the heart of the debate over early primate evolution. Even the placement of Tarsiiformes within suborder Haplorhini, as a sister group to the simians (monkeys and apes), is still debated.

Classification

Generally accepted members of this infraorder include the living tarsiers, the extinct omomyids, two extinct fossil genera, and two extinct fossil species within the genus ''Tarsius''. As haplorhines, they are more closely related to monkeys and apes than to the

strepsirrhine Strepsirrhini or Strepsirhini (; ) is a suborder of primates that includes the lemuriform primates, which consist of the lemurs of Madagascar, galagos ("bushbabies") and pottos from Africa, and the lorises from India and southeast Asia. Colle ...

primates, which include

lemur Lemurs ( ) (from Latin ''lemures'' – ghosts or spirits) are wet-nosed primates of the superfamily Lemuroidea (), divided into 8 families and consisting of 15 genera and around 100 existing species. They are endemic to the island of Madagas ...

galago Galagos , also known as bush babies, or ''nagapies'' (meaning "night monkeys" in Afrikaans), are small nocturnal primates native to continental, sub-Sahara Africa, and make up the family Galagidae (also sometimes called Galagonidae). They are ...

s, and

loris Loris is the common name for the strepsirrhine mammals of the subfamily Lorinae (sometimes spelled Lorisinae) in the family Lorisidae. ''Loris'' is one genus in this subfamily and includes the slender lorises, ''Nycticebus'' is the genus conta ...

es. * Order

Primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians ( monkeys and apes, the latter including ...

s ** Suborder Strepsirrhini: lemurs, lorises, and galagos ** Suborder Haplorhini *** Infraorder

: monkeys and apes *** Infraorder Tarsiiformes/Omomyiformes **** Archicebidae **** Family Tarsiidae: tarsiers ***** Genus †'' Afrotarsius'' ***** Genus †'' Xanthorhysis'' ***** Genus ''

Tarsius ''Tarsius'' is a genus of tarsiers, small primates native to islands of Southeast Asia. Until 2010, all tarsier species were typically assigned to this genus, but a revision of the family Tarsiidae restored the generic status of ''Cephalopach ...

'' ***** Genus ''

Cephalopachus Horsfield's tarsier (''Cephalopachus bancanus''), also known as the western tarsier, is the only species of tarsier in the genus ''Cephalopachus''. Named for American naturalist Thomas Horsfield, it occurs on Borneo, Sumatra and nearby islands a ...

'' ***** Genus '' Carlito

Footnotes

References

{{Authority control Tarsiers Extant Thanetian first appearances Taxa named by William King Gregory Taxa described in 1915