| Argyrohyrax Temporal range: Late Oligocene ~ | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | † Notoungulata |
| Family: | † Interatheriidae |
| Subfamily: | † Interatheriinae |
| Genus: | † Argyrohyrax Ameghino, 1897 |
| Type species | |
| †Argyrohyrax proavus Ameghino, 1897 | |
| Synonyms | |
| |
Argyrohyrax is an extinct genus of interatheriid notoungulate that lived during the Late Oligocene, of what is now Argentina and Bolivia.
This animal may have vaguely resembled a medium-sized ground-dwelling rodent, such as a marmot. Its skull was approximately 15 centimeters long, and its entire body may have reached one meter in length, including the tail. Argyrohyrax is differentiated from its closest relatives like Archaeophylus and Cochilius by small differences in its dentition, notably the overlap of the first premolar base by parts of the canine and the second premolar. Its maxilla had a very prominent descending process, as in Cochilius. The two first lower molars had a quadrangular trigonid and a subcircular talonid. The first lower premolar was canine-like.
Compared to some of its later relatives, Interatherium and Protypotherium , Argyrohyrax had a moderately expanded zygomatic arch; its radius had a slightly concave distal articular surface, and the articulation between its ulna and its humerus was less concave and more vertical.
Argyrohyrax proavus was first described in 1897 by Florentino Ameghino; he later described several other species, such as Argyrohyrax acuticostatus, A. concentricus, A. nesodontoides, A. proavunculus, currently considered identical to the type species. The genus Plagiarthrus is similarly considered synonymous with Argyrohyrax. [1] The genus Argyrohyrax is known from several fossilized remains discovered in Argentina, notably from the Sarmiento Formation in the provinces of Santa Cruz and Chubut, from the Agua de la Piedra Formation in Mendoza Province and from the Fray Bentos Formation in the Corrientes Province. [2]
Argyrohyrax belonged to the family Interatheriidae, a group of medium-sized notoungulates, with a superficially rodent-like appearance. Several characteristics of its skull and dentition suggests that Argyrohyrax was nested as a basal member of the group.
Pyrotherium is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina and Bolivia, during the Late Oligocene. It was named Pyrotherium because the first specimens were excavated from an ancient volcanic ash deposit. Fossils of the genus have been found in the Deseado and Sarmiento Formations of Argentina and the Salla Formation of Bolivia.
Interatherium is an extinct genus of interatheriid notoungulate from the Early to Middle Miocene (Colhuehuapian-Mayoan). Fossils have been found in the Santa Cruz, Collón Curá and Sarmiento Formations in Argentina.
Prosotherium is an extinct genus of hegetotheriid notoungulate. It lived during the Late Oligocene, and its fossilized remains were found in South America.
Proadiantus(Ameghino, 1897) is an extinct genus of adianthid litoptern. It lived during the Late Oligocene, in what is today South America. It consists of only 1 species, Proadiantus excavatus.
Proadinotherium is an extinct genus of toxodontid. It lived between the Late Oligocene and the Early Miocene in what is now South America.
Eohyrax is an extinct genus of Notoungulate, belonging to the suborder Typotheria. It lived during the Middle Eocene, and its remains were discovered in South America.
Pseudhyrax is an extinct genus of archaeohyracid notoungulate. It lived from the Late Eocene to the Early Oligocene, of what is now South America.
Propachyrucos is an extinct genus of hegetotheriid notoungulate. It lived from the Late Oligocene to the Early Miocene, in what is today South America.
Isotemnus is an extinct genus of notoungulate belonging to the family Isotemnidae. It lived from the Late Paleocene to the Middle Eocene of what is now Argentina.
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.
Pleurostylodon is an extinct genus of notoungulate belonging to the family Isotemnidae. It lived during the Middle Eocene, in what is now Argentina.
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.
Ancylocoelus is an extinct genus of mammal, belonging to the order Notoungulata. It lived during the Late Oligocene, in what is today Argentina, in South America.
Archaeopithecus is an extinct genus of Notoungulate, belonging to the suborder Typotheria. It lived during the Middle Eocene, in what is today Argentina.
Oldfieldthomasia is an extinct genus of Notoungulate, probably related to the suborder Typotheria. It lived during the Middle Eocene, in what is today South America.
Patriarchus is an extinct genus of interatheriid notoungulates that lived during the Early Miocene in what is now Argentina. Fossils of this genus have been found in the Santa Cruz Formation of Argentina.
Cochilius is an extinct genus of interatheriid notoungulate that lived between the Late Oligocene and the lower Miocene in what is now Argentina.
Notopithecus is an extinct genus of Notoungulate, belonging to the suborder Typotheria. It lived from the Middle to the Late Eocene and its fossilized remains were discovered in South America.
