''Nexuotapirus'' is an extinct genus of tapir from the

Late Oligocene The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest stage ...

and

Early Miocene The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 Ma to 15.97 ± 0.05 Ma (million years ago). It was prece ...

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

Taxonomy

''Nexuotapirus'' was erected in 1998. The type species, ''N. marslandensis'', was originally classified under ''

Miotapirus ''Miotapirus harrisonensis'' is an extinct species of tapir lived during the early Miocene Epoch some 20 million years ago in North America. Physically ''Miotapirus'' was virtually identical to its modern relatives; with a length of 2 m (6 f ...

''. The second species, ''N. robustus'', was originally placed in ''

Protapirus ''Protapirus'' (Latin: "before" (pro), + Brazilian Indian: "tapir" (tapira)) is an extinct genus of tapir known from the Oligocene and Miocene of North America and Eurasia. Taxonomy The type species is ''Protapirus priscus'' from the Late Oligoce ...

'' but was also moved to ''Nexuotapirus'' based on comparable lower dentition.

Description

''Nexuotapirus'' shows both

plesiomorphic In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades. Plesiomorphy, symplesiomorphy, apomorphy, and ...

and derived features compared to other early tapirs, making its exact relationship with them difficult to place. Primitive traits of the genus include less molar-like premolars and incisive foramina that extend posteriorly through the postcanine diastema, as well as a braincase that tapers towards the back. More advanced features include deep retraction of the nasal incision, nasal shortening, frontal shortening, and reduction of the supraorbital process, features comparable to the modern ''

Tapirus ''Tapirus'' is a genus of tapir which contains the three living American tapir species. The Malayan tapir is usually included in ''Tapirus'' as well, although some authorities have moved it into its own genus, ''Acrocodia''. Extant species The ...

''.

References

{{Taxonbar, from=Q108336593 Prehistoric tapirs Oligocene odd-toed ungulates Oligocene mammals of North America Miocene odd-toed ungulates Miocene mammals of North America