Dino card No. 1543 of 2,015

Richardoestesia

Say it: rih-KAR-doh-es-TEE-zha

Name means: “Richard Estes' lizard”1

Ate: MeatRaptorsLate Jurassic to Late Cretaceous

Richardoestesia is known only from its teeth, which are long, slender, and curved. These teeth tell us it was a meat-eating dinosaur that hunted small animals like lizards and mammals.1

Lived

155 to 66 million years ago2

Late Jurassic to Late Cretaceous

Fossils found in

Alberta, Canada; many states in the USA (including Montana, Wyoming, Texas); also Spain, France, Romania, Uzbekistan, and Mexico2

Food

Meat2

Artist's life restoration of Richardoestesia — How Richardoestesia may have looked, by LancianIdolatry. CC BY-SA 4.0, via Wikimedia Commons. Scientists still argue about colours and details.

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

cool stuff

Fun facts

Richardoestesia is known only from its teeth, not from whole skeletons. Scientists call it a 'form taxon' because they group similar-looking teeth together.1

The teeth of Richardoestesia are very long and slender compared to other meat-eating dinosaurs. They look like thin blades.1

If all the teeth assigned to Richardoestesia really belong to the same kind of dinosaur, it would have lived for over 80 million years, from the Late Jurassic to the end of the Cretaceous.1

Richardoestesia teeth have been found all over the world, including North America, Europe, and Asia. That would make it one of the most widespread dinosaurs ever.1

The name Richardoestesia honors paleontologist Richard Estes, who studied small fossils and dinosaur teeth.1

Some scientists think Richardoestesia might have been a dromaeosaur (a raptor) or a troodontid, but nobody knows for sure because no body fossils have been found.2

Myth buster

Myth: Richardoestesia is a well-known dinosaur with a complete skeleton.

Truth: Richardoestesia is only known from isolated teeth. No complete skeleton has ever been found, so scientists are not sure what it looked like.1

For dino experts

Scientific name: Richardoestesia
Named by: Currie et al. 19902
Group: Raptors
Family / clade: Dromaeosauridae2
Classification: Theropoda > Dromaeosauridae2
Age of the rocks: 155 to 66 million years (Kimmeridgian to Maastrichtian)2
Rock formations: Hell Creek, Milk River, Dinosaur Park2
Countries: USA, Canada, Spain, Uzbekistan, Romania, Mexico2
Fossil records: 239 in the Paleobiology Database2
Discovery: The first Richardoestesia fossils were jaws found in 1917 by Charles Hazelius Sternberg and his sons in Dinosaur Provincial Park, Alberta, Canada. The name was given in 1990 by paleontologist Philip Currie and colleagues.1
Still debated: Scientists are not sure if all the teeth called Richardoestesia really belong to the same dinosaur. Many may come from different species that have not been named yet.1

Where the facts come from

Richardoestesia (en.wikipedia.org)
Richardoestesia in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.

Every fact on this page has a number that points to its source. If we got something wrong, sorry, we are dino fans, not a science journal. Tell us at [email protected] and we will fix it.