Oxyaenidae is a family of extinct carnivorous placental mammals. Traditionally classified in order Creodonta, this group is now classified in its own order Oxyaenodonta within clade Pan-Carnivora in mirorder Ferae. The group contains four subfamilies comprising fourteen genera. Oxyaenids were the first to appear during the late Paleocene in North America, while smaller radiations of oxyaenids in Europe and Asia occurred during the Eocene.
Taeniodonta is an extinct order of eutherian mammals, that lived in North America and Europe from the late Cretaceous (Maastrichtian) to middle Eocene.
Stylinodon is an extinct genus of taeniodonts from extinct tribe Stylinodontini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from early to middle Eocene.
Psittacotherium is an extinct genus of taeniodonts from extinct tribe Psittacotheriini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from early to late Paleocene. With a weight between 35.6 kg (78 lb) and 71.2 kg (157 lb), and length of 1.125 m, it had similar size of a large dog.
Tillodontia is an extinct suborder of eutherian mammals known from the Early Paleocene to Late Eocene of China, the Late Paleocene to Middle Eocene of North America where they display their maximum species diversity, the Middle Eocene of Pakistan, and the Early Eocene of Europe. Leaving no descendants, they are most closely related to the pantodonts, another extinct group. The tillodonts were medium- to large-sized animals that probably fed on roots and tubers in temperate to subtropical habitats.
Brontotheriidae is a family of extinct mammals belonging to the order Perissodactyla, the order that includes horses, rhinoceroses, and tapirs. Superficially, they looked rather like rhinos with some developing bony nose horns, and were some of the earliest mammals to have evolved large body sizes of several tonnes. They lived around 56–34 million years ago, until the very close of the Eocene. Brontotheres had a Holarctic distribution, with the exception of Western Europe: they occupied North America, Asia, and Eastern Europe. They were the first fossilized mammals to be discovered west of the Mississippi, and were first discovered in South Dakota.
Sinopa is an extinct genus of placental mammals from extinct family Sinopidae within extinct order Hyaenodonta, that lived in North America and Asia from the early to middle Eocene.
The Washakie Formation is a geologic formation in northern Colorado and southern Wyoming. It preserves many mammal, bird, reptile and other fossils dating back to the Lutetian stage of the Eocene within the Paleogene period. The sediments fall in the Bridgerian and Uintan stages of the NALMA classification.
The San Jose Formation is an Early Eocene geologic formation in the San Juan Basin of New Mexico and Colorado.
Hyainailouridae ("hyena-cats") is a family of extinct predatory mammals within the superfamily Hyainailouroidea within extinct order Hyaenodonta. Hyaenodontids arose during the middle Eocene and persisted well into the middle Miocene. Fossils of this group have been found in Asia, Africa, North America and Europe.
Ectoganus is an extinct genus of taeniodonts from tribe Ectoganini within subfamily Stylinodontinae and family Stylinodontidae, that lived in North America from late Paleocene to early Eocene.
Oxyaeninae is an extinct subfamily of placental mammals from extinct family Oxyaenidae, that lived in Asia, North America and Europe from the late Paleocene to middle Eocene.
Conoryctella is an extinct genus of taeniodonts from extinct tribe Conoryctellini within extinct subfamily Conoryctinae and extinct family Conoryctidae, that lived in North America during the early Paleocene.
Sinopidae is an extinct family of predatory placental mammals from extinct order Hyaenodonta. Fossil remains of these mammals are known from early to middle Eocene deposits in North America, Europe and Asia.
Metacheiromyidae is an extinct paraphyletic family of myrmecophagous placental mammals within extinct order Palaeanodonta, that lived in North America and Europe from the late Paleocene to middle Eocene.
Conoryctidae is an extinct family of mammals from extinct order Taeniodonta, that lived in North America and Europe from the early Paleocene to early Eocene.
Stylinodontinae is an extinct subfamily of mammals from extinct family Stylinodontidae, that lived in North America from the early Paleocene to middle Eocene.
Conoryctinae is an extinct subfamily of taeniodonts from extinct family Conoryctidae, that lived in North America from the early to middle Paleocene.
Wortmania is an extinct genus of taeniodonts from extinct subfamily Wortmaniinae within extinct family Stylinodontidae, that lived in North America during the early Paleocene.
