''Santiagorothia'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of interatheriid

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

. It lived during the Early

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

, and its fossils were discovered in

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 ...

and

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

Description

This animal was about the size of a large

paca A paca ia a rodent in South and Central America. Paca or PACA may also refer to: People * William Paca (1740–1799), a Founding Father of the United States * Paca Blanco (Francisca Blanco Díaz, born 1949), Spanish activist * Paca Navas (Franc ...

. It could reach 65 centimeters in length including its tail, with a skull approximately 10–11 centimeters ; it weighed between 5 and 7 kilograms. Like its relatives, it had an elongated body, with strong legs, and compared to some of its more basal relatives, such as '' Notopithecus'', it had more elongated legs and high-crowned (hypsodont) teeth. The molars of ''Santiagorothia'' were similarly sized to those of

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

Archaeohyracidae Archaeohyracidae is an extinct family of Notoungulata, notoungulate mammals known from the Paleocene through the Oligocene of South America.McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Colum ...

, such as ''

Pseudhyrax ''Pseudhyrax'' is an extinct genus of archaeohyracidae, archaeohyracid notoungulate. It lived from the Late Eocene to the Early Oligocene, of what is now South America. Description This animal was approximately the size of a modern raccoon, and ...

''. The first incisors of ''Santiagorothia'' were enlarged and positioned straight in the alveoli, somewhat similar to

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

dentition. The upper premolars had two vertical ridges (ectoloph) and deep grooves on both sides of the lower premolars and molars, separating the anterior (trigonid), from the posterior (talonid).

Classification

''Santiagorothia'' was first described in 2000, based on fossils found in

, near the

Tinguiririca River Tinguiririca River is a river of Chile located in the Libertador General Bernardo O'Higgins Region. It rises in the Andes, at the confluence of the rivers ''Las Damas'' and ''Del Azufre''. From its source, it flows northwest for about 56 km ...

, and in

in deposits of the

Sarmiento Formation The Sarmiento Formation (Spanish language, Spanish: ''Formación Sarmiento''), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million y ...

, dating to the Early Oligocene. ''Santiagorothia'' is an interatheriid, a family of small to medium-sized notoungulates, with similarities to rodents. ''Santiagorothia'' was an archaic interatheriid, less specialized than the later '' Cochilius'', ''

Miocochilius ''Miocochilius'' is an extinct genus of small Notoungulata, notoungulate mammals (typotheria, typotheres) native to South America. The genus lived during the Miocene, Middle Miocene epoch (Laventan in the South American land mammal age, SALMA cla ...

'', ''

Protypotherium ''Protypotherium'' is an extinct genus of Notoungulata, notoungulate mammals native to South America during the Oligocene and Miocene epoch (geology), epochs. A number of closely related animals date back further, to the Eocene. Fossils of ''Prot ...

'' and '' Interatherium''.

Paleobiology

''Santiagorothia'' was a terrestrial herbivore, which fed on low vegetation in open areas, and was probably quite fast and agile.

Etymology

The genus is named for

Santiago Roth Santiago Roth (14 June 1850 – 4 August 1924) was a Swiss Argentine paleontologist and academic known for his fossil collections and Patagonian expeditions. Life Kaspar Jakob (Spanish: Santiago) was born and raised in Herisau, Canton Appenzell ...

, "in honor of his contributions to South American paleontology".

References

*R. Hitz, M. Reguero, A. R. Wyss and J. J. Flynn. 2000. New interatheriines (Interatheriidae, Notoungulata) from the Paleogene of Central Chile and Southern Argentina. Fieldiana: Geology (New Series) 42:1-26 *M. A. Reguero and F. J. Prevosti. 2010. Rodent-like notoungulates (Typotheria) from Gran Barranca, Chubut Province, Argentina: phylogeny and systematics. In R. H. Madden, A. A. Carlini, M. G. Vucetich, R. F. Kay (eds.), The Paleontology of Gran Barranca: Evolution and Environmental Change through the Middle Cenozoic of Patagonia 148–165 {{Taxonbar, from=Q9333768 Typotheres Oligocene mammals of South America Paleogene Argentina Fossils of Argentina Paleogene Chile Fossils of Chile Tinguirirican Fossil taxa described in 2000 Prehistoric placental genera Golfo San Jorge Basin