''Altitypotherium'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

Notoungulate Notoungulata is an extinct order of mammalian ungulates that inhabited South America from the early Paleocene to the Holocene, living from approximately 61 million to 11,000 years ago. Notoungulates were morphologically diverse, with forms resem ...

, belonging to the suborder Typotheria. It lived during the Early

Miocene The Miocene ( ) is the first 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 means "less recent" ...

, and its fossilized remains were discovered 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 souther ...

Description

This animal was vaguely similar to a

wombat Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. They are about in length with small, stubby tails and weigh between . All three of the extant species are members of the family Vombatidae. They are ad ...

, and its dimensions evocate those of a

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight o ...

; its skull was approximately 16 centimeters long, while its total length, excluding the tail, was about 80 centimeters. It weighed around 10 kilograms. ''Altitypotherium'' had a tall and narrow snout, with only six pairs of teeth in the maxilla and mandible, a low number when compared to most other notoungulates. It had gliriform upper incisors, with a band of anterior enamel, and lower incisors protruding forward and separated from premolars and molars by a long diastema. It had high-crowned (hypsodont) teeth, and the occlusal surfaces of the molars had two enamel folds halfway through the tooth in the inner surface and outlining three dentin-filled lobes, forming an E-shaped form. The largest species, ''Altitypotherium paucidens'' was distinguished from its closest relatives by the loss of the upper third molar.

Classification

The genus ''Altitypotherium'' was first described in 2004, based on fossil remains found in the Chucal Formation in Northern

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...

, in Early

terrains ; two species are currently known, ''A. chucalensis'' and ''A. paucidens''. Fossils attributed, with some uncertainty, to the genus have also been found in Argentina. ''Altitypotherium'' belonged to the family

Mesotheriidae Mesotheriidae ("Middle Beasts") is an extinct family of notoungulate mammals known from the Oligocene through the Pleistocene of South America. Mesotheriids were small to medium-sized herbivorous mammals adapted for digging. Characteristics M ...

, a group of

typotheres Typotheria is a suborder of the extinct mammalian order Notoungulata and includes five families: Archaeopithecidae, Campanorcidae, Interatheriidae Interatheriidae is an extinct family of notoungulate mammals from South America. Interath ...

that diversified during the

Cenozoic The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configu ...

, giving rise to forms the size of a

ram Ram, ram, or RAM may refer to: Animals * A male sheep * Ram cichlid, a freshwater tropical fish People * Ram (given name) * Ram (surname) * Ram (director) (Ramsubramaniam), an Indian Tamil film director * RAM (musician) (born 1974), Dutch ...

. ''Altitypotherium'' belonged to the subfamily

Mesotheriinae Mesotheriidae ("Middle Beasts") is an extinct Family (biology), family of Notoungulata, notoungulate mammals known from the Oligocene through the Pleistocene of South America. Mesotheriids were small to medium-sized herbivorous mammals adapted fo ...

, the most derived clade of the group.

Paleobiology

''Altitypotherium'' was a terrestrial herbivore with fossorial behaviour. It fed on low vegetation, roots and tubers, which it grinded with its powerful posterior teeths. It lived at fairly high altitudes. It shared several similarities, notably its hypsodont teeth, with modern wombats.

Bibliography

*D. A. Croft, J. J. Flynn, and A. R. Wyss. 2004. Notoungulata and Litopterna of Early Miocene Chucal Fauna, Northern Chile. Fieldiana Geology 50:1-52 *G. M. López, M. G. Vucetich, A. A. Carlini, M. Bond, M. E. Pérez, M. R. Ciancio, D. J. Pérez, M. Arnal, and A. I. Olivares. 2011. New Miocene mammal assemblages from Neogene Manantiales basin, Cordillera Frontal, San Juan, Argentina. In J. A. Salfity, R. A. Marquillas (eds.), Cenozoic Geology of the Central Andes of Argentina 211–226 {{Taxonbar, from=Q60978383 Typotheres Miocene mammals of South America Neogene Chile Fossils of Chile Fossil taxa described in 2004 Prehistoric placental genera