Paraceratherium

Paraceratherium ^[1] is an extinct genus of mammal. It was a large rhinoceros without a horn. It lived in Eurasia during the late Oligocene epoch of the Tertiary period, (34–23 million years ago).

Paraceratherium Temporal range: Oligocene, 34–23 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Mounted P. transouralicum skeleton, Moscow Paleontological Museum; this is the most completely known skeleton, but the skull is a cast of a specimen at American Museum of Natural History
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Perissodactyla
Family:	†Paraceratheriidae
Genus:	†Paraceratherium Forster-Cooper, 1911
Type species
†Aceratherium bugtiense Pilgrim, 1908
Species
†P. bugtiense (Pilgrim, 1908) †P. transouralicum (Pavlova, 1922) †P. huangheense Li et al., 2017 †P. linxiaense Deng et al., 2021
Synonyms
Genus synonymy Baluchitherium Forster-Cooper, 1913 Indricotherium Borissiak, 1916 Pristinotherium Birkjukov, 1953 ?Benaratherium Gabunia, 1955 Species synonymy P. bugtiense: Aceratherium bugtiense Pilgrim, 1908 Thaumastotherium osborni Forster-Cooper, 1913 (preoccupied) Baluchitherium osborni (Forster-Cooper, 1913) Metamynodon bugtiensis Forster-Cooper, 1922 Paraceratherium zhajremensis Bayshashov, 1988 P. transouralicum: Indricotherium transouralicum Pavlova, 1922 Baluchitherium grangeri Osborn, 1923 Indricotherium asiaticum Borissiak, 1923 Indricotherium minus Borissiak, 1923 Indricotherium grangeri (Osborn, 1923) Pristinotherium brevicervicale Birjukov, 1953 Dubious names: Benaratherium callistratum Gabunia, 1955

P. transouralicum skull, American Museum of Natural History

Estimated size of P. transouralicum compared with that of humans

Paraceratherium was one of the largest ever land mammals.^[2] Its exact size is unclear because of the incompleteness of the fossils. The size of adults was about 4.8 metres (16 ft) tall at the shoulder, about 7.4 metres (24 ft) in length. Estimates of its weight have varied greatly.

Lifestyle

It was a herbivore that stripped leaves from trees. It had a long, low, hornless skull and long frontal and nasal bones. Its front teeth had a single pair of incisors in either jaw. They were round, pointed, and so large that they looked like small tusks. The upper incisors pointed straight downwards, while the lower ones jutted outwards. The upper lip was evidently extremely mobile. The neck was very long, the body big and strong, and the limbs long and thick, column-like.^[3]

Size

Its exact size is unclear because of the incompleteness of the fossils. Estimates have been based on skull, teeth, and limb bone measurements. However, the known bone elements are from individuals of different sizes. All skeletal reconstructions are composite extrapolations. This resulted in weight estimates from 11 to 20 tonnes.^[4][5][6][7] Its shoulder height has been estimated as 4.8 metres (16 ft).^[7] Its length was about 7.4 metres (24 ft) from front to back.^[5] As explained, such figure are only approximations. These figures are for the largest of the three species in the genus.

Ecology

They lived in a huge rainforest floodplain in the area which is now Kazakhstan, India, and southwest China. They lived further inland throughout northern and central Asia as well. This area was a rainforest before the Himalayan uplift changed the climate.