Neogene Argentina

family of mammals

Megatherium ( ; from Greek () 'great' + () 'beast') is an extinct genus of large ground sloths endemic to South America that lived from the Early Pliocene through the end of the Late Pleistocene. It is best known for the elephant-sized, type species Megatherium americanum, primarily known from the Pampas, but ranging southwards to northernmost Patagonia and northwards to southern Bolivia during the late Middle Pleistocene and Late Pleistocene. Various other species have been described, including those belonging to the Andean subgenus Pseudomegatherium, which range in size from comparable to M.

The genus Hydrochoerus contains two living (the lesser and greater capybaras) and three extinct species of rodents from South America, the Caribbean island of Grenada, California and Panama. Capybaras are the largest living rodents. The name of the genus is derived from Ancient Greek ὕδωρ (húdor), meaning "water", and χοῖρος (khoîros), meaning "pig".

Thylacosmilus is an extinct genus of saber-toothed metatherian mammals that inhabited South America from the Late Miocene to Pliocene epochs. Though Thylacosmilus looks similar to the "saber-toothed cats", it was not a felid, like the well-known American Smilodon, but a sparassodont, a group closely related to marsupials, and only superficially resembled other saber-toothed mammals due to convergent evolution, with the aforementioned Thylacosmilus being one of the last known sparassodonts. A 2005 study found that the bite forces of Thylacosmilus and Smilodon were low, which indicates that the

Macrauchenia ("long llama", based on the now-invalid llama genus, Auchenia, from Greek "big neck") is an extinct genus of large ungulate native to South America from the Pliocene or Middle Pleistocene to the end of the Late Pleistocene. It was one of the last surviving members of the extinct order Litopterna, a group of South American native ungulates distinct from the two orders which contain all living ungulates which had been present in South America since the early Cenozoic, over 60 million years ago, prior to the arrival of living ungulates in South America around 2.5 million years ago as

Toxodon (from Ancient Greek τόξον (tóxon), meaning "bow", and ὀδούς (odoús), meaning "tooth", in reference to the curvature of the teeth) is an extinct genus of large ungulate native to South America from the Pliocene to the end of the Late Pleistocene. Toxodon is a member of Notoungulata, an order of extinct South American native ungulates distinct from the two living ungulate orders that had been indigenous to the continent for over 60 million years since the early Cenozoic, prior to the arrival of living ungulates into South America around 2.5 million years ago during the Great American Int

Kelenken is a genus of phorusrhacid ("terror bird"), an extinct group of large, predatory birds, which lived in what is now Argentina in the middle Miocene about 15 million years ago. The only known specimen was discovered by high school student Guillermo Aguirre-Zabala in Comallo, in the region of Patagonia, and was made the holotype of the new genus and species Kelenken guillermoi in 2007. The genus name references a spirit in Tehuelche mythology, and the specific name honors the discoverer. The holotype consists of one of the most complete skulls known of a large phorusrhacid, as well as a

Brontornis is an extinct genus of giant bird that inhabited Argentina during the Early to Middle Miocene. Its taxonomic position is highly controversial, with authors alternatively considering it to be a cariamiform, typically a phorusrhacid (terror bird) or an anserimorph.

Thalassocnus is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—T. antiquus, T. natans, T. littoralis, T. carolomartini, and T. yuacensis—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths, but they may have also been adapted to a terrestrial lifestyle. They have been found in the Pisco Formation of Peru, the Tafna Formation of Argentina, and the Bahía Inglesa, Coquimbo, and Ho

Andalgalornis is a genus of flightless predatory birds of the extinct family Phorusrhacidae (often called "terror birds") that lived in Argentina. The type and only species is A. steulleti.

Astrapotherium ("lightning beast") is an extinct genus of large astrapotherian ungulate native to South America during the early-middle Miocene. It is the best known member of the group. The type species. A. magnum have been found in the Santa Cruz Formation in Argentina. Other fossils have been found in the Deseado, Sarmiento, and Aisol Formations of Argentina and Chile (Cura-Mallín Group).

Borhyaena is an extinct genus of South American metatherian within borhyaenaid, a family of mammalian predators part of the now extinct order Sparassodonta. The genus lived from 21 to 15.5 million years ago from the Early to Middle Miocene.

Platygonus ("flat head" in reference to the straight shape of the forehead) is an extinct genus of herbivorous peccaries of the family Tayassuidae, endemic to North and South America from the Miocene through Pleistocene epochs (10.3 million to 11,000 years ago), existing for about . P. compressus stood tall.

Argentavis is an extinct genus of teratornithid known from three sites in the Epecuén and Andalhualá Formations in central and northwestern Argentina dating to the Late Miocene (Huayquerian). The type species, A. magnificens, is sometimes called the giant teratorn. Argentavis was among the largest flying birds to ever exist, holding the record for heaviest flying bird, although it was surpassed in wingspan after the 2014 description of Pelagornis sandersi, which is estimated to have possessed wings some 20% longer than those of Argentavis.

Chapalmalania is an extinct genus of procyonid from the Late Miocene or Early Pliocene to Early Pleistocene (Montehermosan to Uquian) of Argentina (Andalhualá Formation), Venezuela (San Gregorio Formation, Venezuela), and Colombia (Ware Formation, Cocinetas Basin, La Guajira).

Gryposuchus (meaning "hooked crocodile") is an extinct genus of gavialid crocodilian. Fossils have been found from Argentina, Colombia, Venezuela, Brazil and the Peruvian Amazon. The genus existed during the Miocene epoch (Colhuehuapian to Huayquerian). One recently described species, G. croizati, grew to an estimated length of . Gryposuchus is the type genus of the subfamily Gryposuchinae, although a 2018 study indicates that Gryposuchinae and Gryposuchus might be paraphyletic and rather an evolutionary grade towards the gharial.

thumb|Skull of P. ferox Peltephilus, the horned armadillo, is an extinct genus of armadillo xenarthran mammals that first inhabited Argentina during the Oligocene epoch, and became extinct in the Miocene epoch. Notably, the scutes on its head were so developed that they formed horns. Aside from the horned gophers of North America, it is the only known fossorial horned mammal.

Llallawavis scagliai (magnificent bird of Scaglia) is a large, extinct predatory bird from Pliocene Argentina. Its fossil is the most complete fossil of a phorusrhacid (or "terror bird") yet found.

Kentriodon is an extinct genus of toothed whale related to modern-day dolphins. Fossils have been found in North America, Europe and Japan. Several species have been described.

Necrolestes (from Ancient Greek νεκρός (necrós), meaning "dead", and λῃστής (lēistḗs), meaning "robber") 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 (marsupials and placentals) 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 f

species of fossil sharks

thumb | right | alt=A 10cm skull of Phoberomys pattersoni in ventral view | The skull of Phoberomys pattersoni Phoberomys is an extinct genus of rodents. Fossil specimens from the Late Miocene period have been discovered in the Ituzaingó Formation of Argentina, the Solimões Formation of Brazil, the Urumaco Formation at Urumaco in Venezuela, and the Pliocene of Peru.

thumb|left|Life restoration of Hapalops longiceps and Propalaehoplophorus australis thumb|left|Skeleton

Cladosictis (meaning "branch weasel") is an extinct genus of South American metatherian from Patagonia, Argentina (Chichinales, Cerro Bandera, Sarmiento and Santa Cruz Formations) and Chile (Río Frias Formation).

Megapiranha is an extinct serrasalmid characin fish from the Late Miocene (8–10 million years ago) Ituzaingó Formation of Argentina, described in 2009. The type species is M. paranensis. It is thought to have been about in length and in weight. The holotype consists only of premaxillae and a zigzag tooth row; the rest of its body is unknown. This dentition is reminiscent of both the double-row seen in pacus, and the single row seen in the teeth of modern piranhas, suggesting that M. paranensis is a transitional form. Its bite force is estimated between .

Metaxytherium is an extinct genus of dugong that lived from the Oligocene until the end of the Pliocene. Fossil remains have been found in Africa, Europe, North America and South America. Generally marine seagrass specialists, they inhabited the warm and shallow waters of the Paratethys, Mediterranean, Caribbean Sea and Pacific coastline. American species of Metaxytherium are considered to be ancestral to the North Pacific family Hydrodamalinae, which includes the giant Steller's sea cow.

Homalodotherium is an extinct genus of South American native ungulates in the order Notoungulata. Fossils of Homalodotherium have been found in the Middle Miocene (Friasian in the SALMA classification) Santa Cruz Formation of Argentina and the Río Frías Formation of Chile. The first specimen, a partial skull, was discovered by Robert Holiver Cunningham while on an expedition to Patagonia. By the time it had arrived in England, it was degraded to the point where only a few elements remained. Regardless, in 1870, it was given its genus name by Thomas Henry Huxley, and its species name (H. cunnin

Adinotherium (meaning "not terrible beast") is an extinct genus of toxodontid, large bodied hoofed ungulates which inhabited South America during the Middle to Late Miocene, from 17.5 to 6.8 Ma and existed for approximately , Santacrucian to Huayquerian in the South American land mammal ages (SALMA). Fossils of Adinotherium have been found in the Santa Cruz and Ituzaingó Formations of Argentina and the Chucal and Río Frías Formations of Chile.

Theosodon is an extinct genus of litoptern mammal from the Early to Middle Miocene of South America.

Thoatherium (meaning "active swift-beast") is an extinct genus of litoptern mammals from the Early Miocene of Argentina. Fossils of the genus have been found in the Santa Cruz Formation in Argentina. With a length of , the gazelle-like Thoatherium was a small representative of the order Litopterna. Judging from its long legs, it was a fast runner. Thoatherium had remarkably reduced toes; only one horse-like hoof remained. Thoatherium even lacked splint bones, which are remnants of the second and fourth toe found in modern horses. Judging from its generalised, brachydont teeth, Thoatherium fed

Mourasuchus is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck-like, being broad, flat, and very elongate, superficially resembling Stomatosuchus from the Late Cretaceous.

Pachyrukhos is an extinct genus of hegetotheriid notoungulate from the Early to Middle Miocene (Colhuehuapian-Friasian in the SALMA classification) of Argentina and Chile. Fossils of this genus have been found in the Collón Curá, Sarmiento and Santa Cruz Formations of Argentina and the Río Frías Formation of Chile.

Diadiaphorus is an extinct genus of litoptern mammal from the Miocene of Argentina (Ituzaingó, Pinturas, Chiquimil and Santa Cruz Formations) and Bolivia (Nazareno Formation), South America.

Argyrolagus is an extinct genus of South American metatherian, belonging to the order Polydolopimorpha from the Early Pliocene Monte Hermoso Formation, Patagonia, Argentina.

Devincenzia is an extinct genus of giant flightless predatory birds in the family Phorusrhacidae or "terror birds" that lived during the Early Miocene (Deseadan) Fray Bentos Formation of Uruguay, Late Miocene (Huayquerian) Ituzaingó Formation, Early Pliocene (Montehermosan) of Argentina, and possibly the Early Pleistocene Raigón Formation of Uruguay. The type species D. pozzi was formerly known as Onactornis pozzi. The largest possible specimen weighed up to , making it one of the largest phorusrhacids and carnivorous birds known.

Prothylacinus is an extinct genus of South American metatherian, that lived during the Early Miocene.

Prosqualodon is an extinct genus of Early to Middle Miocene cetacean from Argentina, Australia, New Zealand, and Venezuela.

Protypotherium is an extinct genus of notoungulate mammals native to South America during the Oligocene and Miocene epochs. A number of closely related animals date back further, to the Eocene. Fossils of Protypotherium have been found in the Deseadan Fray Bentos Formation of Uruguay, Muyu Huasi and Nazareno Formations of Bolivia, Cura-Mallín and Río Frías Formations of Chile, and Santa Cruz, Salicas, Ituzaingó, Aisol, Cerro Azul, Cerro Bandera, Cerro Boleadoras, Chichinales, Sarmiento and Collón Curá Formations of Argentina.

Lycopsis is an extinct genus of South American metatherian that lived during the Miocene in Argentina and Colombia.

genus of mammals

Patagornis is a genus of extinct flightless predatory birds of the family Phorusrhacidae. Known as "terror birds", these lived in what is now Argentina during the Early and Middle Miocene; the Santa Cruz Formation in Patagonia contains numerous specimens. Patagornis was an agile, medium sized Patagornithine and was likely a pursuit predator.

Procariama is an extinct monotypic genus of phorusrhacid, which lived from the Late Miocene to the Late Pliocene (11-2 million years ago) of Argentina. Fossils of the animal have been found in six places, in the Cerro Azul and Andalhuala Formations. More specifically in the Andagalá department and in the north of the Belén department of the Catamarca province, with a single location in the La Pampa province. The type and only species, Procariama simplex, is the largest member of the subfamily Psilopterinae.

Parastrapotherium is an extinct genus of South American land mammal that existed from the Late Oligocene (Deseadan SALMA) to the Early Miocene (Colhuehuapian SALMA). The genus includes some of the largest and smallest known astrapotherians, but has no generally recognized description.

Lestodon is an extinct genus of giant ground sloth native to South America during the Pleistocene epoch. Its fossil remains have primarily been found in the Pampas and adjacent regions. The largest member of the family Mylodontidae, It is estimated to have weighed . It was a herbivore and primarily fed on the grasses and low-growing plants.

Nesodon ("island tooth") is a genus of Miocene mammal belonging to the extinct order Notoungulata which inhabited southern South America during the Late Oligocene to Miocene living from 29.0 to 16.3 Ma and existed for approximately . It had a relatively large size, weighing up to 554 kg (1221 lbs) and reaching 1.5 m in height.

Neotamandua is an extinct genus of anteaters that lived in the Miocene to Pliocene in South America.

Andrewsornis is an extinct genus of giant flightless predatory birds of the family Phorusrhacidae or "terror birds" that lived in Oligocene Argentina. Fossils have been found in the Sarmiento Formation, and possibly the Agua de la Piedra Formation.

Aulophyseter is an extinct genus of sperm whales from the subfamily Physeterinae that existed during the Miocene.

Cyonasua (meaning "dog-coati" in Greek) is an extinct genus of procyonid from the Late Miocene to Middle Pleistocene of South America. Fossils of Cyonasua have been found in Argentina (Ituzaingó, Epecuén, Huayquerías, Monte Hermoso, Chapadmalal, Maimará, Ensenada, La Playa, Chiquimil, Andalhuala, and Cerro Azul Formations), Bolivia (Tariquía Formation), Uruguay (Camacho Formation), and Venezuela (San Gregorio Formation). The oldest well-dated fossils of Cyonasua are approximately 7.3 million years old. Most fossils of Cyonasua are late Miocene to early late Pliocene (Huayquerian to Chapadmalal

Trigodon is an extinct genus of the family Toxodontidae, a large-bodied notoungulate which inhabited South America during the Late Miocene to Early Pliocene (Mayoan to Montehermosan in the SALMA classification), living from 11.61 to 4.0 Ma which existed for approximately . The type species is T. gaudryi. It bore a superficial resemblance to a rhinoceros, in that it had a horn on its forehead, and was one of a few horned notoungulates, including Adinotherium and Leontinia.

Aglaocetus is a genus of extinct baleen whales known from the Miocene of Patagonia, the US Eastern Seaboard, Japan and the Low Countries. It was once considered a member of Cetotheriidae along with many other putative cetotheres, but was recently recognized as representing a distinct family from true Cetotheriidae.

Interatherium is an extinct genus of interatheriid notoungulate that lived from the Early to Middle Miocene (Colhuehuapian-Mayoan). Fossils of this genus have been found in the Santa Cruz, Collón Curá and Sarmiento Formations in Argentina.

Palaeomyrmidon is an extinct genus of anteater. Its closest living relative is the silky anteater (Cyclopes didactylus). Although the silky anteater is arboreal, Palaeomyrmidon lived on the ground. Palaeomyrmidon is known from a fossil skull that was found in the Andalhualá Formation of Argentina.

Paraptenodytes is an extinct genus of penguins which contains two or three species sized between a Magellanic penguin and an emperor penguin (Aptenodytes forsteri). They are known from fossil bones ranging from a partial skeleton and some additional material in the case of P. antarcticus, the type specimen for the genus, and a single humerus in the case of P. brodkorbi. The latter species is therefore often considered invalid; a recent study considers it indeed valid, but distinct enough not to belong into Paraptenodytes. The fossils were found in the Santa Cruz and Chubut Provinces of Patagon

Trachytherus is an extinct genus of mesotheriid notoungulate that lived from the Late Oligocene to the Early Miocene in what is now South America.

Eutatus is an extinct genus of large armadillos of the family Chlamyphoridae. It was endemic to South America from the Early Miocene to Late Pleistocene, living from 17.5 Ma-11,000 years ago, with possible survival into the early Holocene (~ 7,500 BP) and existing for approximately .

Protamandua is an extinct genus of anteaters. Its closest living relatives are the giant anteater (Myrmecophaga tridactyla) and tamanduas (genus Tamandua). Fossils of Protamandua are restricted to the Santa Cruz Formation of Argentina. It may have been a common ancestor of Myrmecophaga and Tamandua.

Tremacebus is an extinct genus of New World monkeys from the Early Miocene (Colhuehuapian in the SALMA classification). The type species is T. harringtoni.

Catonyx is an extinct genus of ground sloth of the family Scelidotheriidae, endemic to South America during the Pliocene and Pleistocene epochs. It lived from 2.5 Ma to about 10,000 years ago, existing for approximately . The most recent date obtained is about 9600 B.P.

Hegetotherium is a small to middle-sized extinct genus of mammals, ranging from the size of rabbit (about 20-30 cm/12-16") to a beaver (about 3 ft/1 m) from the Early to Middle Miocene (Colhuehuapian-Colloncuran in the SALMA classification), through Pliocene sites of South America. Fossils of this genus have been found in the Cerro Bandera, Cerro Boleadoras, Chichinales, Collón Curá, Santa Cruz and Sarmiento Formations of Argentina, the Nazareno Formation of Bolivia, and the Galera and Río Frías Formations of Chile.