| Eurygenium Temporal range: Late Oligocene ~ | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | † Notoungulata |
| Family: | † Notohippidae |
| Genus: | † Eurygenium Ameghino 1895 |
| Type species | |
| †Eurygenium latirostris Ameghino 1895 | |
| Species | |
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| Synonyms | |
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Eurygenium is an extinct genus of notoungulate belonging to the family Notohippidae. It lived during the Late Oligocene in what is today South America.
It was a medium-sized mammal ; the best known species, Eurygenium pacegnum, was approximately 80 centimeters long and weighed 10 kilograms. Its body was relatively compact, with more robust legs than its relatives, such as Rhynchippus ; unlike the latter, however, Eurygenium had tetradactyls forelegs and a third trochanter near the femoral midline. The skull of Eurygenium was characterized by a short and broad muzzle, with strong and laterally expanded zygomatic arches. The dentition was devoid of diastema. As in all Notohippidae, premolars and molars had a very high crown (hypsodont). The upper premolars lacked an anterolingual cingulum, while the posterolingual cingulum was reduced. The lower incisors cingulum was reduced or absent, while the lower premolars and molars had a dimple at the trigonid-talonid edge, but there was no dimple in the entolophid.
Eurygenium was a member of Notohippidae, a possibly paraphiletic family of toxodont notoungulates. Eurygenium was a basal representative of a derived group of Notohippids, comprising numerous forms such as Argyrohippus and Rhynchippus .
Eurygenium was first described in 1895 by Florentino Ameghino, based on fossilized remains found in terrains dated from the Late Oligocene in Argentine Patagonia. The type species is Eurygenium latirostris, but Ameghino described himself the species E. normalis, from the Late Oligocene of Patagonia. E. pacegnum was described in 1997, based on relatively well preserved specimens found in the Salla Formation, in Bolivia. [1]
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.
Cephalomyidae is an extinct family of caviomorph rodents from South America. The specific relationships of the family are uncertain, and affinities to both chinchilloid and cavioid rodents have been supported. Most recently, Kramarz in 2005 performed a phylogenetic analysis supporting a relationship to the Cavioidea, as represented by Eocardiidae, although more recent analyses have placed them among the chinchilloids as relatives of the giant neoepiblemid rodents. McKenna and Bell (1997) questioned the validity of the family, placing the cephalomyid genera then known in Dasyproctidae, but Kramarz (2001) subsequently reasserted the distinctiveness of cephalomyids.
Archaeopithecidae is an extinct family comprising two genera of notoungulate mammals, Teratopithecus and Archaeopithecus, both known from the Eocene of Argentina.
Parastrapotherium is an extinct genus of South American land mammal that existed from the Late Oligocene to the Early Miocene. The genus includes some of the largest and smallest known astrapotherian, but at present no generally recognized description can adequately characterize it.
Prosotherium is an extinct genus of late Oligocene hegetotheriid notoungulate. It has been found in two Argentinian fossil formations, ie, the Sarmiento Formation in Chubut Province, and the Agua de la Piedra Formation in Mendoza Province.
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.
Argyrohippus is an extinct genus of notoungulate, belonging to the family Notohippidae. It lived from the Late Oligocene to the Early Miocene, and its fossilized remains were found in 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.
Pleurostylodon is an extinct genus of notoungulate belonging to the family Isotemnidae. It lived during the Middle Eocene, in what is now Argentina.
Asmodeus is an extinct genus of mammal, belonging to the order Notoungulata. 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.
Acoelodus is an extinct genus of placental mammal, belonging to the order Notoungulata. The genus was first described by Florentino Ameghino in 1897. Its fossilized remains were discovered in Casamayoran terrains from Argentine Patagonia.
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.
Argyrohyrax is an extinct genus of interatheriid notoungulate that lived during the Late Oligocene, of what is now Argentina and Bolivia.
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.
Glyptatelus is an extinct genus of glyptodont. It lived from the Late Eocene to the Middle Oligocene in what is now Argentina and Bolivia.
Liarthrus is a genus of astrapotheriid mammal known from the Late Oligocene Sarmiento Formation of Santa Cruz Province, Argentina. It was described by the Argentine paleontologist Florentino Ameghino in 1895 along with several other genera from the "Pyrotherium Beds", which were then believed to date to the Cretaceous period. Ameghino described Liarthus on the basis of fragmentary, being only a right astragalus, premolar 4, and an incomplete premolar from the upper jaws. Only one species was described, L. copei, the species name honoring the American paleontologist Edward Drinker Cope, who lived during the same interval as Ameghino. Liarthrus was synonymized with the other astrapothere Parastrapotherium in 1914 by American mammalogist Frederic Loomis, though it was revalidated by a 2008 analysis of Parastrapotherium. Liarthrus was a herbivorous mammal, being an astrapothere, which had large tusks on their skulls and mandibles in addition to a large body size.
