Amargasaurus is a genus of sauropod dinosaur from the Early Cretaceous epoch of what is now Argentina. The only known skeleton was discovered in 1984 and is virtually complete, including a fragmentary skull, making Amargasaurus one of the best-known sauropods of its epoch. Amargasaurus was first described in 1991 and contains a single known species, Amargasaurus cazaui. It was a large animal, but small for a sauropod, reaching 9 to 13 meters in length. Most distinctively, it sported two parallel rows of tall spines down its neck and back, taller than in any other known sauropod. In life, these spines could have stuck out of the body as solitary structures that supported a keratinous sheath. An alternate hypothesis, now more favored, postulates that they could have formed a scaffold supporting a skin sail. They might have been used for display, combat, or defense.
Patagosaurus is an extinct genus of eusauropod dinosaur from the Middle-Late Toarcian of Patagonia, Argentina. It was first found in deposits of the Cañadón Asfalto Formation, which date to around 179 to 177 million years ago. Although originally twelve specimens were assigned to the taxon, at least one of them may belong to a different genus. Patagosaurus probably lived alongside genera as Piatnitzkysaurus, Condorraptor and Volkheimeria.
Prosqualodon is an extinct genus of Early to Middle Miocene cetacean from Argentina, Australia, New Zealand and Venezuela.
Notosuchus is an extinct genus of South American notosuchian crocodyliforms. It was terrestrial, living approximately 85 million years ago in the Santonian stage of the Late Cretaceous.
Chubutherium is an extinct genus of ground sloth from the Late Oligocene and Early Miocene of Chubut Province, Argentina.
Notobatrachus is an extinct genus of frog from the Lower Jurassic (Toarcian) Cañadon Asfalto Formation, Cañadón Asfalto Basin and Middle Jurassic La Matilde Formation, Deseado Massif of Patagonia, Argentina. N. degiustoi is the most completely known Jurassic frog and has been recorded in many outcrops of the La Matilde Formation of the Deseado Massif in southern Patagonia.
Ilchunaia is an extinct genus of sebecid mesoeucrocodylian. Fossils have been found from the Divisadero Largo Formation of Argentina dating back to the Late Eocene, and a locality in Mendoza, Argentina dating back to the Oligocene. Little material is known from the genus, with only the anterior portion of the skull being present to study.
Condorchelys was a genus of stem turtle from Early Jurassic Cañadon Asfalto Formation of Argentina. Condorchelys represents the oldest Jurassic-aged Turtle from South America, with only one species described, Condorchelys antiqua.
Panthera onca mesembrina, also known as the Patagonian panther, is an extinct subspecies of jaguar that was endemic to southern Patagonia during the late Pleistocene epoch. It is known from several fragmentary specimens, the first of which found was in 1899 at "Cueva del Milodon" in Chile. These fossils were referred to a new genus and species "Iemish listai" by naturalist Santiago Roth, who thought they might be the bones of the mythological iemisch of Tehuelche folklore. A later expedition recovered more bones, including the skull of a large male that was described in detail by Angel Cabrera in 1934. Cabrera created a new name for the giant felid remains, Panthera onca mesembrina, after realizing that its fossils were near-identical to modern jaguars’. P. onca mesembrina's validity is disputed, with some paleontologists suggesting that it is a synonym of Panthera atrox.
Pipoidea are a clade of frogs, that contains the most recent common ancestor of living Pipidae and Rhinophrynidae as well as all its descendants. It is broadly equivalent to Xenoanura.
Leonerasaurus is a basal genus of sauropodomorph dinosaur. Currently, there is only one species known, named L. taquetrensis by Diego Pol, Alberto Garrido and Ignacio A. Cerda in 2011. The fossil, an incomplete subadult individual, was found in the Las Leoneras Formation in Argentina. This formation is probably Early Jurassic in age. Leonerasaurus was a small non-sauropod sauropodomorph, showing an unusual combination of basal and derived characters. This indicates that the evolution of early sauropodomorphs witnessed a great degree of convergent evolution.
Proborhyaenidae is an extinct family of metatherian mammals of the order Sparassodonta, which lived in South America from the Eocene (Mustersan) until the Oligocene (Deseadan). Sometimes it has been included as a subfamily of their relatives, the borhyaenids. The largest species, Proborhyaena gigantea, is estimated to be about the size of a spectacled bear, with its skull reaching 60 cm (2.0 ft) in length, and body mass estimates up to approximately 90–200 kg (200–440 lb), making the proborhyaenids some of the largest known metatherians. Proborhyaenid remains have been found in western Bolivia, Uruguay, southern Brazil, and the provinces of Mendoza, Salta, and Chubut, in Argentina.
Necrolestes is an extinct genus of mammals, which lived during the Early Miocene in what is now Argentine Patagonia. It is the most recent known genus of Meridiolestida, an extinct group of mammals more closely related to therians than to monotremes, which were the dominant mammals in South America during the Late Cretaceous. It contains two species, N. patagonensis and N. mirabilis; the type species N. patagonensis was named by Florentino Ameghino in 1891 based on remains found by his brother, Carlos Ameghino in Patagonia. Fossils of Necrolestes have been found in the Sarmiento and Santa Cruz Formations. Its morphology suggests that it was a digging, subterranean-dwelling mole-like mammal that fed on invertebrates.
Astraponotus is an extinct genus of astrapotheriids. It lived during the Middle-Late Eocene and its fossil remains have been found in the Sarmiento Formation of Argentina, South America.
Víctor Alberto Ramos is an Argentine geologist who has contributed to the paleogeography and plate tectonics of South America. He has been a member of the Chilean Academy of Science since 2001 and won in 2013 the Premio México de Ciencia y Tecnología.
Asfaltovenator is a genus of possibly allosauroid dinosaur from the Lower Jurassic Cañadón Asfalto Formation of Chubut Province, Argentina. The type and only species is Asfaltovenator vialidadi.
Bagualia, is an extinct genus of eusauropod dinosaur, from the Early Jurassic Epoch in what is now the Chubut Province of Argentina. The type species, B. alba, was formally described in 2020. Bagualia represents the oldest definitive Eusauropod, and due to the completeness of its material it represents one of the most important taxa for understanding the early evolution of the group.
Stromaphorus is an extinct genus of Glyptodont. It lived during the Late Miocene, and its fossilized remains were discovered in South America.
Peltephilidae is a family of South American cingulates (armadillos) that lived for over 40 million years, but peaked in diversity towards the end of the Oligocene and beginning of the Miocene in what is now Argentina. They were exclusive to South America due to its geographic isolation at the time, one of many of the continent's strange endemic families. Peltephilids are one of the earliest known cingulates, diverging from the rest of Cingulata in the Early Eocene.
The Cañadón Asfalto Formation is a geological formation which dates to the Toarcian age of the Early Jurassic period of Argentina. The rocks of the formation preserve a diverse biota, including plants, dinosaurs, invertebrates, mammals and pterosaurs, among others. The formation is divided into two members: the lower Las Chacritas Member, and the overlying Puesto Almada member, though the latter has also been assigned to the overlying Cañadón Calcáreo Formation by some authors. The members are typically composed of fluvial-lacustrine deposits consisting of sandstones and shales, with a limestone carbonate evaporitic sequence also being present in the lower of the two.
