''Morphippus'' 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 nom ...

of notohippid

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 resemb ...

that lived during the Middle to Late Oligocene in what is now

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 sout ...

Description

This animal, only known from fragmentary remains, was approximately the size of a goat. Its skull was rather massive and had a short muzzle. The dentition was complete and continuous (without diastema), and the premolars and molars were high-crowned (hypsodont), like in its relative ''

Rhynchippus ''Rhynchippus'' ("Snout Horse") is an extinct genus of notoungulate mammals from the Late Oligocene ( Deseadan in the SALMA classification) of South America. The genus was first described by Florentino Ameghino in 1897 and the type species is ' ...

''. The premolars had a well developed cingulum, while the molars were elongated. The shape of the premolars and molars was reminiscent to those of

Equidae Equidae (sometimes known as the horse family) is the taxonomic family of horses and related animals, including the extant horses, asses, and zebras, and many other species known only from fossils. All extant species are in the genus '' Equus'', ...

. ''Morphippus'', like its relatives, may have had a robust body with slender limbs.

Classification

The genus ''Morphippus'' was first described in 1897 by

Florentino Ameghino Florentino Ameghino (born Giovanni Battista Fiorino Giuseppe Ameghino September 19, 1853 – August 6, 1911) was an Argentine naturalist, paleontologist, anthropologist and zoologist, whose fossil discoveries on the Argentine Pampas, especially ...

, based on fossils found in Late Oligocene terrains from Argentine

Patagonia Patagonia () refers to a geographical region that encompasses the southern end of South America, governed by Argentina and Chile. The region comprises the southern section of the Andes Mountains with lakes, fjords, temperate rainforests, and g ...

; the type species is ''Morphippus imbricatus''. Numerous other species have been attributed to the genus, such as ''M. complicatus'', ''M. fraternus'', ''M. hypselodus'', ''M. quadrilobus'', ''M. corrugatus'', but several of them may be synonymous with the type species or with ''Rhynchippus equinus''. ''Morphippus'' was a member of the family

Notohippidae Notohippidae is a paraphyly, paraphyletic extinct Family (biology), family of Notoungulata, notoungulate mammals from South America. Notohippids are known from the Eocene and Oligocene Epoch (reference date), epochs.McKenna, Malcolm C., and Bell ...

, a group of Notoungulates whose members developed teeth reminiscent of those of horses, despite not being closely related with Equidae. This family is considered by some researchers to be paraphyletic, and may include forms nested at the base of the family

Toxodontidae Toxodontidae is an extinct family of notoungulate mammals, known from the Oligocene to the Holocene (11,000 BP) of South America, with one genus, ''Mixotoxodon'', also known from the Pleistocene of Central America and southwestern North America ...

Bibliography

*F. Ameghino. 1897. Mammiféres crétacés de l’Argentine (Deuxième contribution à la connaissance de la fauna mammalogique de couches à Pyrotherium) retaceous mammals of Argentina (second contribution to the knowledge of the mammalian fauna of the Pyrotherium Beds) Boletin Instituto Geografico Argentino 18(4–9):406-521 *F. Ameghino. 1901. Notices préliminaires sur des ongulés nouveaux des terrains crétacés de Patagonie reliminary notes on new ungulates from the Cretaceous terrains of Patagonia Boletin de la Academia Nacional de Ciencias de Córdoba 16:349-429 *G. M. López, A. M. Ribeiro, and M. Bond. 2010. The Notohippidae (Mammalia, Notoungulata) from Gran Barranca: preliminary considerations. 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 143–151 {{Taxonbar, from=Q60978273 Toxodonts Oligocene mammals of South America Paleogene Argentina Fossils of Argentina Fossil taxa described in 1897 Taxa named by Florentino Ameghino Prehistoric placental genera Golfo San Jorge Basin Sarmiento Formation