Castoridae is a family of rodents that cointains the two living species of beavers and their fossil relatives. A formerly diverse group, only a single genus is extant today, Castor. Two other genera of "giant beavers", Castoroides and Trogontherium, became extinct in the Late Pleistocene.
Platybelodon is an extinct genus of large herbivorous proboscidean mammals related to modern-day elephants, placed in the "shovel tusker" family Amebelodontidae. Species lived during the middle Miocene Epoch in Africa, Asia and the Caucasus.
Embolotherium is an extinct genus of brontothere that lived in Mongolia during the late Eocene epoch. It is most easily recognized by a large bony protuberance emanating from the anterior (front) of the skull. This resembles a battering ram, hence the name Embolotherium. The animal is known from about 12 skulls, several jaws, and a variety of other skeletal elements from the Ulan Gochu formation of Inner Mongolia and the Irgilin Dzo of Outer Mongolia.
Toxodon is an extinct genus of South American mammals from the Late Miocene to early Holocene epochs. It is a member of Notoungulata, one of several now extinct orders of South American native ungulates distinct from living perissodactyls and artiodactyls. It was among the largest and last members of its order, and was probably the most common large hoofed mammal in South America of its time.
Titanotylopus is an extinct genus of camel, endemic to North America from the late Hemphillian stage of the Miocene through the Irvingtonian stage of the Pleistocene. It was one of the last surviving North American camels; after its extinction, only Camelops remained.
Macrauchenia was a large, long-necked and long-limbed, three-toed native South American ungulate in the order Litopterna. The genus gives its name to its family, the Macraucheniidae or "robust litopterns". Like other litopterns, it is most closely related to the odd-toed ungulates (Perissodactyla), from which litopterns diverged approximately 66 million years ago. The oldest fossils in the genus date to the late Miocene, around seven million years ago, and M. patachonica disappears from the fossil record during the late Pleistocene, around 20,000-10,000 years ago. M. patachonica is one of the last and best known member of the family and is known primarily from the Luján Formation in Argentina, but is known from localities across southern South America. Another genus of macraucheniid Xenorhinotherium was present in northeast Brazil and Venezuela during the Late Pleistocene. The type specimen was discovered by Charles Darwin during the voyage of the Beagle. In life, Macrauchenia may have resembled a humpless camel, though the two taxa are not closely related. It fed on plants in a variety of environments across what is now South America. Among the species described, M. patachonica and M. ullomensis are considered valid; M. boliviensis is considered a nomen dubium; and M. antiqua has been moved to the genus Promacrauchenia.
Macropoma is an extinct genus of coelacanth in the class Sarcopterygii. Fossils of Macropoma have been found in both England and Czech Republic, dating to the mid-Cretaceous (Albian-Turonian). Recorded fossils have bodies under two feet in length. A modern coelacanth measures five or more, but in other respects the two genera are remarkably similar, and share the same body plan with a three-lobed tail and stalked fins.
Proceratosaurus is a genus of carnivorous theropod dinosaur from the Middle Jurassic (Bathonian) of England. It contains a single species. P. bradleyi, known from a mostly complete skull and lower jaws. Proceratosaurus was a small dinosaur, estimated to measure around 3 m (9.8 ft) in length. Its name refers to how it was originally thought to be an ancestor of Ceratosaurus, due to the partially preserved portion of the crest of Proceratosaurus superficially resembling the small crest of Ceratosaurus. Now, however, it is considered a coelurosaur, specifically a member of the family Proceratosauridae, and amongst the earliest known members of the clade Tyrannosauroidea.
Araeoscelis is an extinct genus of reptile, and potentially one of the earliest diapsids. Fossils have been found in the Nocona, Arroyo and Waggoner Ranch Formations in Texas, dating to the Early Permian. Two species have been described, A. casei and A. gracilis.
Palorchestes is an extinct genus of large terrestrial, herbivorous Australian marsupial of the family Palorchestidae, living from the Miocene through to the Late Pleistocene. Like other palorchestids, it had highly retracted nasal region suggesting that it had a prehensile lip, as well as highly unusual clawed forelimbs that were used to grasp vegetation.
Icaronycteris is an extinct genus of microchiropteran (echolocating) bat that lived in the early Eocene, approximately 52.2 million years ago, making it the earliest known definitive bat. Four exceptionally preserved specimens, among the best preserved bat fossils, are known from the Green River Formation of North America. The best known species is I. index. Fragmentary material from France has also been tentatively placed within Icaronycteris as the second species I. menui. I. sigei is based on well-preserved fragments of dentaries and lower teeth found in Western India. In 2023, the species I. gunnelli also from the Green River Formation was distinguished from I. index, and I. menui and I. sigei were proposed to be removed from the genus due to them not being closely related.
Chapalmalania is an extinct genus of procyonid from the Late Miocene or Early Pliocene to Early Pleistocene of Argentina, Venezuela, and Colombia.
Agriotherium is an extinct genus of bears whose fossils are found in Miocene through Pleistocene-aged strata of North America, Eurasia, and Africa. This long-lived genus persisted from at least ~11.6–2.5 Mya. Materials from the late-surviving A. africanum in Africa have suggested that A. africanum died out during the early Gelasian.
Acrophoca longirostris, sometimes called the swan-necked seal, is an extinct genus of Late Miocene pinniped. It was thought to have been the ancestor of the modern leopard seal; however, it is now thought to be a species of monk seal.
Prorastomus sirenoides is an extinct species of primitive sirenian that lived during the Eocene Epoch 40 million years ago in Jamaica.
Rytiodus is an extinct genus of sirenian, whose fossils have been discovered in France, Europe and Libya.
Didolodus is an extinct genus of mammals from Middle Eocene Argentina. It is an ungulate mammal of uncertain affinities, possibly related to Litopterna, though this is uncertain due to the lack of reliable post-cranial remains, and for now remains Meridiungulata incertae sedis. Its remains were found in the Sarmiento Formation of Patagonia.
Homalodotherium is an extinct genus of notoungulate mammals native to South America. Fossils of Homalodotherium have been found in the Middle Miocene Santa Cruz Formation of Argentina and the Río Frías Formation of Chile.
Sivatherium is an extinct genus of giraffids that ranged throughout Africa to the Indian subcontinent. The species Sivatherium giganteum is, by weight, one of the largest giraffids known, and also one of the largest ruminants of all time.
Zygomaturus is an extinct genus of giant marsupial belonging to the family Diprotodontidae which inhabited Australia from the Late Miocene to Late Pleistocene.
