''Tapirus mesopotamicus'' is an extinct species of

tapir Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a Suidae, pig, with a short, prehensile nose trunk (proboscis). Tapirs inhabit jungle and forest regions of South America, South and Centr ...

that lived in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

during the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

. It is considered a possible ancestor of all extant South American tapirs.

Description

This species was originally described by B. S. Ferrero and J. I. Noriega in 2007. Their description was based on quite complete cranial pieces exhumed from sediments of the

Luján River The Luján River ( Spanish, Río Luján) runs from its source near Espora about west of Buenos Aires, Argentina, to its outflow into the Río de la Plata north of the city. The first ''Megatherium ''Megatherium'' ( ; from Greek () 'great' + ...

in the Diamante department, in the province of Entre Ríos, in central-eastern

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

. The type specimen is CICYTTP-PV-M-1-23, a skull and proximal fragment of the right jaw. Its type locality is the north bank of the Ensenada stream, on a Pleistocene lake-fluvial horizon in the "Arroyo Feliciano formation" of Argentina. It is described as having a long and robust skull, with a short rostrum with respect to the total length of the skull. The skull has a single, non-arched

sagittal crest A sagittal crest is a ridge of bone running lengthwise along the midline of the top of the skull (at the sagittal suture) of many mammalian and reptilian skulls, among others. The presence of this ridge of bone indicates that there are excepti ...

, large flat parietal bones on the anterior skull cover, with the temporal crests converging very close to the frontal-parietal suture. The palate is highly arched, the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

is deeply serrated above the

canine Canine may refer to: Zoology and anatomy * Animals of the family Canidae, more specifically the subfamily Caninae, which includes dogs, wolves, foxes, jackals and coyotes ** ''Canis'', a genus that includes dogs, wolves, coyotes, and jackals ** Do ...

, and the upper jaw and base of the

zygomatic process The zygomatic processes (aka. malar) are three processes (protrusions) from other bones of the skull which each articulate with the zygomatic bone. The three processes are: * Zygomatic process of frontal bone from the frontal bone * Zygomatic ...

are surprisingly robust. The P1 is short and quadrangular, and the

mandibular condyle The condyloid process or condylar process is the process on the human and other mammalian species' mandibles that ends in a condyle, the mandibular condyle. It is thicker than the coronoid process of the mandible and consists of two portions: the ...

is thin, with the posterior wall flat or somewhat concave. An extensive study of all the ''

Tapirus ''Tapirus'' is a genus of tapir which contains the living 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 Kabomani tapir ...

'' materials collected in the fossil deposits of South America concluded that this is a valid species. On the basis of morphometric analysis of its teeth, it is concluded that ''Tapirus mesopotamicus'' is significantly smaller than the larger fossil or living tapirs, such as ''

Tapirus indicus The Malayan tapir (''Tapirus indicus''), also called Asian tapir, Asiatic tapir, oriental tapir, Indian tapir, piebald tapir, or black-and-white tapir, is the only living tapir species outside of the Americas. It is native to Southeast Asia from ...

'', '' Tapirus oliverasi'', '' Tapirus tarijensis'', and ''

Tapirus haysii ''Tapirus haysii'' is an extinct species of tapir that inhabited North America during the early to middle Pleistocene Epoch (~2.5–1 Ma). These fossil remains of two juvenile ''T. haysii'' were collected in Hillsborough County, Florida on ...

''; and that it was similar in size to '' Tapirus terrestris'' and ''

Tapirus rondoniensis ''Tapirus rondoniensis'' is an extinct species of large sized tapir that lived in northwestern parts of Brazil during the Pleistocene. Fossils of the species were found in the Río Madeira Formation of Rondônia, after which the species is named ...

''.

Habitat and diet

This species, like any member of the ''Tapirus'' genus, is associated with warm climates: rainforest, savanna or humid tropical or subtropical forests near rivers; with a herbivorous diet of leaves and fruits.

References

{{Taxonbar, from=Q6138813 Prehistoric tapirs Pleistocene mammals of South America