''Diceratherium'' (meaning "two horned beast") is an extinct genus of

rhinocerotid A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant taxon, extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family (biology), famil ...

native to

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

during 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 ...

through

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

living from 33.9 to 11.6 mya, existing for approximately . Mass estimates for the type species, ''D. armatum'' average around

Taxonomy

''Diceratherium'' was named by Marsh (1875) based on the type species ''Diceratherium armatum''. It was assigned to

Rhinocerotidae A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant taxon, extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family (biology), famil ...

by Marsh (1875) and Carroll (1988); to Diceratheriinae by Prothero (1998); to

Aceratheriinae Aceratheriinae is an extinct subfamily of rhinoceros endemic to Asia, Africa, Europe, and North America, from the Oligocene through the Pliocene. It lived from 33.9 to 3.4 mya, existing for approximately . Taxonomy Aceratheriinae was named by D ...

by Weidmann and Ginsburg (1999); and to Teleoceratini by Sach and Heizmann (2001). ''Diceratherium'' had two

horn Horn may refer to: Common uses * Horn (acoustic), a tapered sound guide ** Horn antenna ** Horn loudspeaker ** Vehicle horn ** Train horn *Horn (anatomy), a pointed, bony projection on the head of various animals * Horn (instrument), a family ...

s side by side on its nose, which has often led it to be confused with ''

Menoceras ''Menoceras'' ("Crescent Horns") is a genus of extinct, small rhinocerotids endemic to most of southern North America and ranged as far south as Panama during the early Miocene epoch. It lived from around 23.1-12.5 Ma, existing for approximately ...

''.D.R. Prother
"Rhinocerotidae"
C.M. Janis, K.M. Scott, L. Jacobs (Eds.), Evolution of Tertiary Mammals of North America, Cambridge University Press, Cambridge (1998), pp. 595-605

"Blue Lake Rhino"

A full-body mold of a ''Diceratherium'' exists as an impression in a cliff on the shore of Blue Lake near Coulee City,

Washington Washington most commonly refers to: * George Washington (1732–1799), the first president of the United States * Washington (state), a state in the Pacific Northwest of the United States * Washington, D.C., the capital of the United States ** A ...

. The impression is a lava cast that is thought to be of a mature individual that died in a shallow lake and was rapidly buried by a basalt flow during the mid-

(about 15 million years ago), creating a three-dimensional mold of its body. The mold formed a rhinoceros-shaped cave on exposed rocks belonging to the

Columbia River Basalt Group The Columbia River Basalt Group (CRBG) is the youngest, smallest and one of the best-preserved continental flood basalt provinces on Earth, covering over mainly eastern Oregon and Washington, western Idaho, and part of northern Nevada. The b ...

, which was first discovered by two

Seattle Seattle ( ) is the most populous city in the U.S. state of Washington and in the Pacific Northwest region of North America. With a population of 780,995 in 2024, it is the 18th-most populous city in the United States. The city is the cou ...

couples searching for

petrified wood Petrified wood (from Ancient Greek meaning 'rock' or 'stone'; literally 'wood turned into stone'), is the name given to a special type of ''fossilized wood'', the fossilized remains of terrestrial plant, terrestrial vegetation. ''Petrifaction ...

in 1935, who also discovered remnant bones of the animal. A replica of the "rhinoceros cave" was created by researchers from the

University of California Museum of Paleontology The University of California Museum of Paleontology (UCMP) is a paleontology museum located on the campus of the University of California, Berkeley. The museum is within the Valley Life Sciences Building (VLSB), designed by George W. Kelham ...

in 1948 and later donated to the

Burke Museum The Burke Museum of Natural History and Culture (commonly as Burke Museum) is a natural history museum on the campus of the University of Washington, in Seattle, Washington (state), Washington, United States. It is administered by the University ...

, where it is on display.

References

Serravallian genus extinctions Oligocene mammals of North America Cenozoic mammals of Europe Cenozoic mammals of Asia Oligocene rhinoceroses White River Fauna Chattian genus first appearances Miocene rhinoceroses Fossil taxa described in 1875 {{paleo-oddtoedungulate-stub