Paraceratheriidae is an extinct family of long-limbed, hornless

rhinocerotoid Rhinocerotoidea is a superfamily (taxonomy), superfamily of Perissodactyla, perissodactyls that appeared 56 million years ago in the Paleocene. They included four extinct families, the Amynodontidae, the Hyracodontidae, the Paraceratheriidae, an ...

s, native to Asia and Eastern Europe that originated in the

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

epoch and lived until the end of the

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

. They represent some of the largest terrestrial mammals to have ever lived.

Description

Paraceratherium-Scale-Diagram-SVG-Steveoc86

The necks and limbs of paraceratheriids are elongate relative to those of living rhinoceroses. The earliest paraceratheres like ''

Juxia ''Juxia'', ‘joo-she-a’, (from ) is an extinct genus of Paraceratheriidae, paraceratheriid, a group of herbivorous mammals that are related to the modern rhinoceros. The type species is ''Juxia sharamurenensis'', named by Zhou Mingzhen and in ...

'' were comparable in size with living rhinoceroses with a body mass of three quarters to one and a half tons, while later members grew substantially larger, with the largest representatives (''

Paraceratherium ''Paraceratherium'' is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch (34–23 ...

'', ''

Dzungariotherium ''Dzungariotherium'' is a genus of paraceratheriid, an extinct group of large, hornless rhinocerotoids, which lived during the middle and late Oligocene of northwest China. The type species ''D. orgosense'' was described in 1973 based on fossils ...

'') estimated to have a body mass of 17 to possibly over 20 tonnes, making them the largest land mammals to have ever lived (though possibly equalled or exceeded by some

proboscideans Proboscidea (; , ) is a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. First described by J. Illiger in 1811, it encompasses the elephants and their close relatives. Three liv ...

in body mass). Non-fostercoopine paraceratheriids are united by the possession of a retracted nasal notch, a lack of contact between the

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

and

nasal Nasal is an adjective referring to the nose, part of human or animal anatomy. It may also be shorthand for the following uses in combination: * With reference to the human nose: ** Nasal administration, a method of pharmaceutical drug delivery * ...

bones of the skull, enlarged upper and lower first

incisors Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...

and small lower

canine Canine may refer to: Zoology and anatomy * Animals of the family Canidae, more specifically the subfamily Caninae, which includes dogs, wolves, foxes, jackals and coyotes ** ''Canis'', a genus that includes dogs, wolves, coyotes, and jackals ** Do ...

teeth, along with characters relating to the size and shape of the molars and premolars. Indricotherium11

Range

Their range spanned from Eastern Europe in the west, the Indian subcontinent in the south, to Northern China in the east.

Ecology

Paraceratheriids are thought to have been primarily

browsers Browse, browser, or browsing may refer to: Computing *Browser service, a feature of Microsoft Windows to browse shared network resources *Code browser, a program for navigating source code *File browser or file manager, a program used to manage f ...

Taxonomy

Although considered a subfamily of the family

Hyracodontidae The Hyracodontidae are an extinction, extinct Family (biology), 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 . The ...

by some authors, recent authors treat the paraceratheres as a distinct family, Paraceratheriidae (Wang et al. 2016 recover hyracodonts as more basal than paraceratheres). Some authors choose to include the small, primitive fosterocoopines (''

Forstercooperia ''Forstercooperia'' is an extinct genus of forstercooperiine indricotheriinae, paraceratheriid rhinocerotoids from the Middle Eocene of Asia. Description ''Forstercooperia'' is known from a vast amount of cranial material, although only some sc ...

Pappaceras ''Pappaceras'' is an extinct genus of rhinocerotoids from the Early Eocene of Asia belonging to Paraceratheriidae. Taxonomy In 1963 in paleontology, 1963, material including a partial skull containing cheek teeth was unearthed in Late Eocene dep ...

'') within the family, while they are excluded by other authors.

References

{{Taxonbar, from=Q1094909 Aquitanian extinctions Eocene first appearances Prehistoric mammal families