Toxodontia is a suborder of the meridiungulate order Notoungulata. Most of the members of the five included families, including the largest notoungulates, share several dental, auditory and tarsal specializations. The group is named after Toxodon, the first example of the group to be discovered by science.
Leontiniidae is an extinct family comprising eighteen genera of notoungulate mammals known from the Middle Eocene (Mustersan) to Late Miocene (Huayquerian) of South America.
Mesotheriidae 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.
The Mustersan age is a period of geologic time within the Eocene epoch of the Paleogene, used more specifically within the South American land mammal age (SALMA) classification. It follows the Casamayoran and precedes the Divisaderan age.
The Tinguirirican age is a period of geologic time within the Late Eocene and Early Oligocene epochs of the Paleogene, used more specifically within the SALMA classification in South America. It follows the Divisaderan and precedes the Deseadan age.
Periphragnis is an extinct genus of isotemnid notoungulates that lived from the Middle Eocene to the Early Oligocene in what is now Argentina and Chile.
Eomorphippus is an extinct genus of notohippid notoungulate that lived from the Late Eocene to the Early Oligocene in what is today South America.
Eurygenium is an extinct genus of notoungulate belonging to the family Notohippidae. It lived during the Late Oligocene in what is today South America.
Morphippus is an extinct genus of notohippid notoungulate that lived during the Middle to Late Oligocene in what is now South America.
Anayatherium is an extinct genus of notoungulate belonging to the family Leontiniidae. It lived during the Late Oligocene, and its fossilized remains were discovered in South America.
Colpodon is an extinct genus of herbivorous mammal, belonging to the order Notoungulata. It lived during the Early Miocene, in what is today Argentina and Chile, in South America.
Elmerriggsia is an extinct genus of Notoungulate, belonging to the family Leontiniidae. It lived during the Late Oligocene in South America.
Martinmiguelia is an extinct genus of Notoungulate, belonging to the family Leontiniidae. It lived during the Middle Eocene, and its fossil remains were found in South America.
Termastherium is an extinct genus of leontiniid notoungulates that lived during the Early Oligocene of what is now Chile. Fossils of this genus have been found in the Oligocene-aged Abanico Formation of Chile.
Archaeopithecus is an extinct genus of Notoungulate, belonging to the suborder Typotheria. It lived during the Middle Eocene, in what is today Argentina.
Santiagorothia is an extinct genus of interatheriid notoungulate. It lived during the Early Oligocene, and its fossils were discovered in Argentina and Chile.
Pascualihippus is an extinct genus of notoungulate belonging to the family Notohippidae. It lived during the Late Oligocene, in what is now Bolivia.
The Sarmiento Formation, in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid-Eocene to the early Miocene. It predominantly consists of pyroclastic deposits, which were deposited in a semi-arid environment. It is divided up into a number of members. The diverse fauna of the Sarmiento Formation, including a variety of birds, crocodilians, turtles and snakes, also includes many mammals such as South American native ungulates as well as armadillos, and caviomorph rodents.
Teushentherium is an extinct genus of notohippid notoungulate from the Oligocene of Argentina. Fossils have been found in the Sarmiento Formation of Argentina.
Moqueguahippus is an extinct genus of notohippid notoungulates that lived during the Late Oligocene of what is now Peru. Fossils of this genus have been found in the Moquegua Formation of Peru, which it was named after.
