Machairodus is a genus of large machairodont or ''saber-toothed cat'' that lived in Africa, Eurasia and North America during the late Miocene. It is the animal from which the subfamily Machairodontinae gets its name. Some species of the genus reached sizes comparable to a tiger, making them apex predators of the ecosystems they inhabited.
Dinofelis is an extinct genus of machairodontine, usually classified in the tribe Metailurini. It was widespread in Europe, Asia, Africa and North America from 5 million to about 1.2 million years ago. Fossils very similar to Dinofelis from Lothagam range back to around 8 million years ago, in the Late Miocene.
Smilodon is an extinct genus of felids. It is one of the best known saber-toothed predators and prehistoric mammals. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats, belonging to the extinct subfamily Machairodontinae, with an estimated date of divergence from the ancestor of living cats around 20 million years ago. Smilodon was one of the last surviving machairodonts alongside Homotherium. Smilodon lived in the Americas during the Pleistocene epoch. The genus was named in 1842 based on fossils from Brazil; the generic name means "scalpel" or "two-edged knife" combined with "tooth". Three species are recognized today: S. gracilis, S. fatalis, and S. populator. The two latter species were probably descended from S. gracilis, which itself probably evolved from Megantereon. The hundreds of specimens obtained from the La Brea Tar Pits in Los Angeles constitute the largest collection of Smilodon fossils.
Homotherium is an extinct genus of scimitar-toothed cat belonging to the extinct subfamily Machairodontinae that inhabited North America, Eurasia, and Africa during the Pliocene and Pleistocene epochs from around 4 million to 12,000 years ago. It was one of the last surviving members of the subfamily alongside the more famous sabertooth Smilodon, to which it was not particularly closely related. It was a large cat, comparable in size to a lion, functioning as an apex predator in the ecosystems it inhabited. In comparison to Smilodon, the canines of Homotherium were shorter, and it is suggested to have had a different ecology from Smilodon as a pursuit predator adapted to running down large prey in open habitats, with Homotherium also proposed to have likely engaged in cooperative hunting.
A saber-tooth is any member of various extinct groups of predatory therapsids, predominantly carnivoran mammals, that are characterized by long, curved saber-shaped canine teeth which protruded from the mouth when closed. Saber-toothed mammals have been found almost worldwide from the Eocene epoch to the end of the Pleistocene epoch.
Machairodontinae is an extinct subfamily of carnivoran mammals of the family Felidae. They were found in Asia, Africa, North America, South America, and Europe, with the earliest species known from the Middle Miocene, with the last surviving species becoming extinct around Late Pleistocene-Holocene transition.
Smilodontini is an extinct tribe within the Machairodontinae or "saber-toothed cat" subfamily of the Felidae. The tribe is also known as the "dirk-toothed cats". They were endemic to South America, North America, Europe, Asia, and Africa during the Miocene to Pleistocene, from 10.3 mya—11,000 years ago, existing for approximately 10.3 million years.
Xenosmilus is an extinct genus of homotherin machairodontine that was discovered in Florida in 2001. It has one species, Xenosmilus hodsonae.
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 North American Smilodon, but a sparassodont, a group closely related to marsupials, and only superficially resembled other saber-toothed mammals due to convergent evolution. A 2005 study found that the bite forces of Thylacosmilus and Smilodon were low, which indicates the killing-techniques of saber-toothed animals differed from those of extant species. Remains of Thylacosmilus have been found primarily in Catamarca, Entre Ríos, and La Pampa Provinces in northern Argentina.
Megantereon is an extinct genus of prehistoric machairodontine saber-toothed cat that lived in North America, Eurasia, and Africa from the late Pliocene to the Middle Pleistocene. It is a member of the tribe Smilodontini, and closely related to and possibly the ancestor of the famous American sabertooth Smilodon. In comparison to Smilodon it was somewhat smaller, around the size of a jaguar, though it is thought to have had a similar hunting strategy as an ambush predator.
Biseridens is an extinct genus of anomodont therapsid, and one of the most basal anomodont genera known. Originally known from a partial skull misidentified as an eotitanosuchian in 1997, another well-preserved skull was found in the Qingtoushan Formation in the Qilian Mountains of Gansu, China, in 2009 that clarified its relationships to anomodonts, such as the dicynodonts.
Thylacosmilidae is an extinct family of metatherian predators, related to the modern marsupials, which lived in South America between the Miocene and Pliocene epochs. Like other South American mammalian predators that lived prior to the Great American Biotic Interchange, these animals belonged to the order Sparassodonta, which occupied the ecological niche of many eutherian mammals of the order Carnivora from other continents. The family's most notable feature are the elongated, laterally flattened fangs, which is a remarkable evolutionary convergence with other saber-toothed mammals like Barbourofelis and Smilodon.
Homotherini (Machairodontini) is a tribe of saber-toothed cats of the family Felidae. The tribe is commonly known as scimitar-toothed cats. These saber-toothed cats were endemic to North America, Europe, Asia, Africa, and South America from the Miocene to Pleistocene living from c. 23 Ma until c. 12,000 years ago. The evolutionary relationship between the tribes Homotherini and Machairodontini cause paleontologists to classify Homotherini either as a subtribe of Machairodontini, or the same tribe often using either name interchangeably.
Amphimachairodus is an extinct genus of large machairodonts. It is also a member of the tribe Homotherini within Machairodontinae and is most closely related to such species as Xenosmilus, Homotherium itself, and Nimravides. It inhabited Eurasia, Northern Africa and North America during the late Miocene epoch.
Promegantereon is an extinct genus of machairodont from the Miocene of Europe. It is one of the oldest machairodont cat species in the Smilodontini and is believed to be an ancestor of Megantereon and Smilodon.
Tchadailurus is a genus of machairodontine felid from the late Miocene of Chad, Africa.
Alligator hailensis, or Haile alligator, is a large, extinct species of Alligator known from the early Pleistocene of Florida. It is named after the town of Haile, Florida, where it was found. Its age and skeletal morphology is intermediate between the geologically older Alligator mefferdi and the modern American alligator, making it a transitional fossil.
Vetusodon is an extinct genus of cynodonts belonging to the clade Epicynodontia. It contains one species, Vetusodon elikhulu, which is known from four specimens found in the Late Permian Daptocephalus Assemblage Zone of South Africa. With a skull length of about 18 centimetres (7.1 in), Vetusodon is the largest known cynodont from the Permian. Through convergent evolution, it possessed several unusual features reminiscent of the contemporary therocephalian Moschorhinus, including broad, robust jaws, large incisors and canines, and small, single-cusped postcanine teeth.
Syntomiprosopus is an extinct genus of archosauriform, possibly a crocodylomorph from the Late Triassic period of Arizona. The type and only known species is S. sucherorum. Syntomiprosopus was unusually short-snouted, comparable to the Late Cretaceous notosuchian Simosuchus, and is regarded as an example of convergent evolution between Triassic stem-archosaurs and Cretaceous archosaurs.
Taowu is an extinct genus of machairodonts, a type of saber-toothed cat. It lived during the Early Pleistocene about 2.5 million years ago in East Asia. So far, only one skull is known, found in northern China. Based on this, a relatively small representative of the saber-toothed cats can be reconstructed, which only reached the size of a present-day leopard. In its dentition characteristics, it mediates between phylogenetic older forms such as Amphimachairodus and younger members such as Homotherium. The genus was scientifically described in 2022, but the find material was recovered as early as the 1930s.
