''Tapirus rondoniensis'' is an extinct species of large sized

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

that lived in northwestern parts of

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

during the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

. Fossils of the species were found in the Río Madeira Formation of

Rondônia Rondônia () is one of the 26 states of Brazil, located in the northern subdivision of the country (central-western part). To the west is a short border with the state of Acre, to the north is the state of Amazonas, in the east is Mato Grosso, ...

, after which the species is named.

Characteristics

This species was originally described by Elizete Celestino Holanda, Ana Maria Ribeiro, and Jorge Ferigolo, in 2011, using materials from the Upper Pleistocene of the Madeira River Formation, in

Araras Araras () is a municipality located in the interior of State of São Paulo, Brazil. The population is 135,506 as of the 2020 IBGE estimate. Etymology Araras means macaws. Sports União São João Esporte Clube, founded in 1981, is the most succ ...

Nova Mamoré Nova Mamoré is a municipality located in the Brazilian state of Rondônia. In 2020, the population of Nova Mamoré was 31,392. Its area is 10,072 km². Economy The economy of Nova Mamoré is based on mainly agriculture and wood. Its main agr ...

municipality, Rondonia state,

. The type specimen of ''Tapirus rondoniensis'' is an almost complete

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

with a unique combination of characteristics that differ from those of current and fossil species of ''

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 ...

'' described in

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. It is mainly identified by its broad frontals that support pneumatization that extends to the frontoparietal suture, a high sagittal crest, and a weakly molarized P2. ''T. rondoniensis'' is similar in some respects to '' T. terrestris'', but retains some primitive cranial and dental character states like '' T. pinchaque'', such as broad fronts and a weakly molarized P2. An extensive study of all the materials collected in the fossil deposits of the ''Tapirus'' genus concluded that this is a valid species. On the basis of morphometric analysis of its teeth, it is concluded that ''T. rondoniensis'' is significantly smaller than most fossil or living tapirs, such as '' T. indicus'', '' T. oliverasi'', '' T. tarijensis'', and '' T. haysii''; and that it was similar in size to ''T. terrestris'' and '' T. mesopotamicus''. On the basis of cladistic-morphological analysis, it was indicated that ''T. rondoniensis'' is the closest species to the living '' T. kabomani'', from which it differs by possessing 3 autapomorphies.

References

Prehistoric tapirs Pleistocene mammals of South America Ensenadan Uquian Pleistocene Brazil Fossils of Brazil Fossil taxa described in 2011 {{paleo-oddtoedungulate-stub