Dino card No. 1822 of 2,015

Troodon

Say it: TROO-oh-don

Name means: “wounding tooth”1

Ate: A bit of everythingRaptorsLate Cretaceous

Troodon was a small, smart dinosaur that lived in North America and Asia. It had big eyes and a big brain, and scientists think it may have eaten both plants and meat. Troodon was not a raptor like Velociraptor, but it was a close cousin.2

Lived

84 to 66 million years ago3

Late Cretaceous

Fossils found in

USA (Montana, Wyoming, North Dakota, South Dakota, Alaska), Canada (Alberta, Saskatchewan), China, and Russia3 2

Food

A bit of everything2

Length

2 to 3.5 m2

estimated

Weight

30 kg to 60 kg2

Height

0.9 to 1.2 m2

at the hips

Artist's life restoration of Troodon — How Troodon may have looked, by ABelov2014. CC BY 3.0, via Wikimedia Commons. Scientists still argue about colours and details.

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

cool stuff

Fun facts

Troodon is often called one of the smartest dinosaurs because its brain was large for its body size.1

Troodon was not a dromaeosaur (the group that includes Velociraptor), but it was closely related to them.2

Some Troodon relatives had a hooked claw on their foot, like the raptors, but scientists think they may have evolved it separately.2

The first Troodon fossil was a single tooth found in Montana in 1855 by Ferdinand Hayden.1

For many years scientists thought Troodon might be a lizard or a pachycephalosaur, until more fossils showed it was a small meat-eating dinosaur.1

Troodon lived about 79 to 75 million years ago, during the Late Cretaceous period.2

Fossils of Troodon have been found in many places, including Alaska, which was much warmer when Troodon was alive.3

Myth buster

Myth: Troodon was a raptor like Velociraptor.

Truth: Troodon was not a dromaeosaur (the group called raptors), but it was a close relative in the troodontid family.2

For dino experts

Scientific name: Troodon
Named by: Leidy 18563
Group: Raptors
Family / clade: Troodontidae3
Classification: Theropoda > Troodontidae3
Age of the rocks: 84 to 66 million years (Campanian to Maastrichtian)3
Rock formations: Dinosaur Park, Oldman, Judith River3
Countries: Canada, USA, Russia, China3
Fossil records: 103 in the Paleobiology Database3
Also known as: Polyodontosaurus (older names now counted as the same animal)3
Discovery: In 1855, Ferdinand Hayden found a single tooth in the Judith River badlands of Montana. Joseph Leidy named it Troodon formosus in 1856, which means 'beautiful wounding tooth'.1
Still debated: Some scientists argue that the name Troodon formosus should be thrown out because the first tooth fossil is too incomplete to be sure it belongs to a unique species.1

Where the facts come from

Troodontid specimens from the Cretaceous Two Medicine Formation of Montana (USA) and the validity of Troodon formosus | Journal of Paleontology | Cambridge Core (cambridge.org)
Troodon | Natural History Museum (nhm.ac.uk)
Troodon 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 hello@dinowiki.app and we will fix it.