Rhinocerotoidea

A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family Rhinocerotidae. It is the only living family in the superfamily Rhinocerotoidea (whose members are also sometimes called rhinoceroses). Two of the extant species are native to Africa, and three to South and Southeast Asia.

The Hyracodontidae are an extinct family of rhinocerotoids endemic to North America, Europe, and Asia during the Eocene through early Oligocene, living from 48.6 to 26.3 million years ago (Mya), existing about .

Rhinocerotoidea is a superfamily of perissodactyls that appeared 56 million years ago in the Paleocene. They included four extinct families, the Amynodontidae, the Hyracodontidae, the Paraceratheriidae, and the Eggysodontidae. The only extant family is the Rhinocerotidae (true rhinoceroses), which survives as five living species. Extinct non-rhinocerotid members of the group are sometimes considered rhinoceroses in a broad sense. Although the term 'rhinoceroses' is sometimes used to refer to all of these, a less ambiguous vernacular term for this group is 'rhinocerotoids'. The family Paracerat

thumb| Tooth paratype of Cadurcotherium nouleti – [[MHNT]] thumb|Zaisanamynodon protheroi

thumb|Skeletal reconstruction of Hyracodon Hyracodon ('hyrax tooth') is an extinct genus of perissodactyl mammal from the White River Formation.

Metamynodon is an extinct genus of amynodont that lived in North America (White River Fauna) and Asia from the late Eocene until early Oligocene, although the questionable inclusion of M. mckinneyi could extend their range to the Middle Eocene. The various species were large, displaying a suit of semiaquatic adaptations more similar to those of the modern hippopotamus, despite their closer affinities with rhinoceroses.

thumb|left|Life restoration Cadurcodon is an extinct genus of amynodont that lived during the Late Eocene to the Oligocene period. Fossils have been found throughout Mongolia and China. It may have sported a tapir-like proboscis due to the distinct features found in fossil skulls.

Eggysodon is an extinct genus of odd-toed ungulate belong to the rhinoceros-like family Eggysodontidae. It was a small, ground-dwelling browser, and fossils have been found in Oligocene deposits throughout Europe. Eggysodon may have been related to Preaceratherium, and both had tusklike canines and smaller, and fewer, incisors.

Uintaceras is an extinct genus of medium-sized early rhinocerotoids that lived in North America (Wyoming and Utah) during the Middle Eocene, with only the type species U. radinskyi, named in 1997, currently contained within the genus. Traditionally considered the oldest and most primitive species of the Rhinocerotidae, it may instead have been a close relative of the Asian Paraceratheriidae. The dubious species Forstercooperia (Hyrachyus) grandis (Radinsky, 1967; Peterson, 1919) is also possibly the same animal as Uintaceras, although the Asian material of F. grandis was assignable to Forsterc