Utah's dinosaurs are Jurassic and Early Cretaceous: Allosaurus, Stegosaurus, Apatosaurus, Diplodocus and Utahraptor. The Paleobiology Database lists 710 dinosaur records among Utah's 11,472 fossil records. Three places explain most of them.
- Cleveland-Lloyd Dinosaur Quarry. A Morrison Formation bone bed with the remains of at least 44 Allosaurus. Allosaurus is the state fossil, adopted in 1988.
- Dinosaur National Monument. The quarry wall on the Utah and Colorado border, where Earl Douglass found an Apatosaurus skeleton in 1909.
- Cedar Mountain Formation near Moab. A large claw found in 1991 led to Utahraptor, named in 1993 and made the state dinosaur in 2018.
Footprints add to the count. Grallator has 66 records and Eubrontes 45, three-toed tracks from the Triassic and Jurassic that the database files under dinosaurs.
Utah's older rock is heavily collected too. The Cambrian has 1,307 records and the Ordovician 1,442. Elrathia, a trilobite 2 to 4 cm long dug from shale in the House Range, has 18 of them.
Dinosaurs found in Utah
The Paleobiology Database lists 710 dinosaur finds in Utah. These are the best documented.
- Allosaurus: A large Late Jurassic predator, 8 to 9 m long, with three-fingered hands and serrated teeth. Found 17 times, from 155 to 143 million years ago.
- Stegosaurus: A plant eater with two rows of upright back plates and four spikes on its tail. Late Jurassic. Found 12 times, from 155 to 93.9 million years ago.
- Apatosaurus: A Late Jurassic long-necked plant eater about 21 m long. Many scientists now treat Brontosaurus as a separate genus. Found 11 times, from 155 to 143 million years ago.
- Diplodocus: A Late Jurassic long-necked plant eater about 25 m long, with a whip-like tail and peg-shaped teeth. Found 5 times, from 155 to 143 million years ago.
- Brachiosaurus: A Late Jurassic plant eater with front legs longer than its hind legs, so its back sloped and its neck rose high. Found 2 times, from 155 to 143 million years ago.
- Acrocanthosaurus: An Early Cretaceous predator about 11 m long with tall spines along its back, among the largest of its time. Found 1 time, from 121 to 101 million years ago.
- Triceratops: A plant eater with three horns and a bony neck frill. It lived until the extinction 66 million years ago. Found 1 time, from 72.2 to 66 million years ago.
- Camarasaurus: A long-necked plant eater with a short, blunt skull and spoon-shaped teeth. Common in Late Jurassic rock. Found 16 times, from 155 to 143 million years ago.
- Grallator: Small three-toed footprints of a meat-eating dinosaur, common in Triassic and Jurassic rock. A track name. Found 66 times, from 251 to 175 million years ago.
- Eubrontes: Large three-toed footprints over 25 cm long, made by a big meat-eating dinosaur. Common in Early Jurassic rock. Found 45 times, from 251 to 175 million years ago.
- Ceratosaurus: A Late Jurassic predator about 6 m long with a horn on its snout and small bony studs down its back. Found 5 times, from 155 to 143 million years ago.
- Alamosaurus: A giant Late Cretaceous long-necked plant eater, among the last sauropods in North America. Found 4 times, from 72.2 to 66 million years ago.
Other fossils found in Utah
Beyond dinosaurs, the Utah record includes these animals and plants.
- Elrathia (trilobite): A small Cambrian trilobite, 2 to 4 cm long, and one of the most commonly collected trilobites in the world. Found 18 times, from 507 to 497 million years ago.
- Mammuthus (mammoth): An Ice Age elephant relative with long curved tusks. Woolly mammoths lived in the north, Columbian ones farther south. Found 5 times, from 0.13 to 0.01 million years ago.
- Equus (horse): The horse genus, with zebras and donkeys. Horses evolved in North America and died out there in the Ice Age. Found 6 times, from 1.4 to 0 million years ago.
- Calamites (giant horsetail): A tree-sized relative of horsetails, up to about 20 m tall. Common in Carboniferous coal swamps. Found 9 times, from 359 to 299 million years ago.
- Smilodon (sabre-toothed cat): An Ice Age big cat with upper canines up to 18 cm long. Often called a sabre-toothed tiger, but not a tiger. Found 2 times, from 0.13 to 0 million years ago.
- Ptychodus: A Late Cretaceous shark with broad, ridged teeth suited to crushing clams and other hard-shelled prey. Found 6 times, from 101 to 89.8 million years ago.
- Lepidodendron (scale tree): A Carboniferous giant relative of club mosses, up to about 30 m tall, with a diamond-patterned trunk. Found 5 times, from 359 to 299 million years ago.
- Edaphosaurus: A plant eater with a tall back sail, from the Carboniferous and Permian. A relative of mammals, not dinosaurs. Found 1 time, from 307 to 274 million years ago.
- Mammut (mastodon): A browsing Ice Age elephant relative with long, upward-curving tusks and ridged, low-crowned teeth. Not a mammoth. Found 1 time, from 0.13 to 0.01 million years ago.
- Bison: The bison genus. Ice Age bison were larger than today's, and Bison latifrons had horns spanning about 2 m. Found 2 times, from 0.13 to 0.01 million years ago.
- Uintatherium (uintathere): A rhino-sized Eocene plant eater with six bony knobs on its skull and long upper canines. Found 3 times, from 45.9 to 39.7 million years ago.
- Megalonyx (Jefferson's ground sloth): A ground sloth about 3 m long. Thomas Jefferson described its claw bones in 1797 and named it for the claw. Found 1 time, from 0.13 to 0.01 million years ago.
State symbols
- State fossil: Allosaurus (adopted 1988) Read the statute
- State dinosaur: Utahraptor (adopted 2018) Read the statute
Utah Code 63G-1-601(17): 'Utah's state fossil is the Allosaurus.' Year 1988 (S.B. 87 signed by Gov. Bangerter) is from the Utah State Library state-symbol page (onlinelibrary.utah.gov/state-symbol/fossil/), which returned HTTP 403 to scripts so was not directly fetched; statute text does not give a year. PBDB: valid. | S.B. 43 (2018 General Session) 'State Dinosaur Amendment' enrolled; codified as Utah Code 63G-1-601(10): 'Utah's state dinosaur is the Utahraptor.' Species name ostrommaysorum is not in the statute. PBDB: Utahraptor valid.
How the land changed
Every fossil records the place it was buried in. Reading those places period by period shows how Utah changed.
- Cambrian (539 to 487 Ma): most fossils from this time come from a shallow sea.
- Ordovician (487 to 443 Ma): most fossils from this time come from a shallow sea.
- Carboniferous (359 to 299 Ma): most fossils from this time come from a shallow sea.
- Triassic (252 to 201 Ma): most fossils from this time come from a shallow sea.
- Jurassic (201 to 143 Ma): most fossils from this time come from a shallow sea.
- Cretaceous (143 to 66 Ma): most fossils from this time come from rivers and lakes.
Oldest and youngest finds in Utah
The oldest find in the Utah record is Itagnostus, dated to about 515 million years ago. The youngest is Equus, from the last 12,000 years.
Fossil finds in Utah by period
| Period | Million years ago | Finds | Most common group |
|---|---|---|---|
| Cambrian | 539 to 487 | 1,307 | Invertebrates |
| Ordovician | 487 to 443 | 1,442 | Invertebrates |
| Silurian | 443 to 420 | 67 | Invertebrates |
| Devonian | 420 to 359 | 136 | Fish and sharks |
| Carboniferous | 359 to 299 | 1,183 | Invertebrates |
| Permian | 299 to 252 | 479 | Invertebrates |
| Triassic | 252 to 201 | 1,731 | Invertebrates |
| Jurassic | 201 to 143 | 1,586 | Invertebrates |
| Cretaceous | 143 to 66 | 2,279 | Reptiles, amphibians and birds |
| Paleogene | 66 to 23 | 1,081 | Mammals |
| Neogene | 23 to 2.6 | 22 | Mammals |
| Quaternary | 2.6 to 0 | 158 | Mammals |
Frequently asked questions
What is the state fossil of Utah?
Utah has designated Allosaurus as its state fossil, adopted in 1988.
What is the state dinosaur of Utah?
Utahraptor is the official state dinosaur of Utah, adopted in 2018.
What dinosaurs have been found in Utah?
The best-documented dinosaurs in the Utah record are Allosaurus, Stegosaurus, Apatosaurus, Diplodocus and Brachiosaurus. The Paleobiology Database lists 710 dinosaur finds there.
How many fossils have been found in Utah?
The Paleobiology Database records 11,472 fossil finds in Utah, covering 1,954 kinds of animals, plants and other life.
What is the oldest fossil found in Utah?
The oldest find in the Utah record is Itagnostus, dated to about 515 million years ago.
How can I see fossils near me in Utah?
Type a town or ZIP code into the search box at the top of this page, or use your location, to see the fossils recorded within 25 to 200 km. Natural history museums and state fossil parks are the best places to see real specimens.
Keep exploring
More fossil states: California, Texas, Wyoming, Florida, New Mexico, Montana, all 50 states.
Credits and data
- Fossil finds: the Paleobiology Database, licensed CC BY 4.0. Counts are records in the database, which reflect research effort as well as geology.
- Ancient Earth maps and plate motion: PALEOMAP PaleoDEMs, Scotese and Wright (2018), CC BY 4.0, doi:10.5281/zenodo.5460860.
- Place names: US Census Gazetteer (public domain) and GeoNames, CC BY 4.0.
- Silhouettes: PhyloPic contributors (Marie Aimee ALLARD, Olivia Binfield, Jagged Fang Designs, Qohelet12, U.S. National Park Service (vectorized by William Gearty), David Orr, Guillaume Dera, Margot Michaud, An Ignorant Atheist, Eliana P. Coturel, Matt Celeskey).