Ahvaytum
Ahvaytum was a tiny, early long-necked dinosaur that lived about 230 million years ago in what is now Wyoming. It is the oldest known dinosaur from the northern half of the ancient supercontinent Pangaea. Ahvaytum was only about as long as a big dog and as tall as a ruler!123
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at the hips (estimate, about 1 foot)
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Fun facts
Ahvaytum's name comes from the Shoshone language, meaning 'long ago'. The species name means 'water's young man' and is also the Shoshone word for dinosaur.1
Scientists found only a few leg bones of Ahvaytum: an ankle bone and a piece of a thigh bone. These small fossils tell us it was a fast-growing, active dinosaur.1
Ahvaytum lived during the Carnian age, about 230 million years ago, which is the same time as the very first dinosaurs in the southern hemisphere.23
The fossils of Ahvaytum were discovered in 2013 in the Popo Agie Formation of Wyoming, a river environment from the Triassic period.1
Ahvaytum was a sauropodomorph, meaning it belonged to the group of long-necked dinosaurs that later included giants like Brachiosaurus. But Ahvaytum was much smaller.1
Most asked questions about Ahvaytum
?How big was Ahvaytum?
About 0.91 metres (3 feet) long and 0.30 metres (1 foot) tall. That is about the size of a chicken with a long tail.15
?Is Ahvaytum the oldest dinosaur?
No, but it is the oldest known named dinosaur from the northern half of the ancient supercontinent Pangaea, called Laurasia. It lived about 230 million years ago.15
?Where was Ahvaytum found?
In the Popo Agie Formation of Wyoming, United States. The fossils were discovered in 2013.1
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For dino experts
- Scientific name
- Ahvaytum
- Named by
- Lovelace et al. 20256
- Group
- Long-necks
- Family / clade
- Sauropodomorpha6
- Classification
- Sauropodomorpha6
- Age of the rocks
- 237 to 227 million years (Carnian)6
- Rock formations
- Popo Agie6
- Countries
- USA6
- Fossil records
- 1 in the Paleobiology Database6
- Discovery
- Ahvaytum was named in 2025 by David M. Lovelace and colleagues, based on fossils found in Wyoming, USA. The name was created with help from Eastern Shoshone elders and students.1
- Still debated
- Scientists are not sure whether Ahvaytum is definitely a sauropodomorph, because the bones are so few. Some think it might belong to another dinosaur group.13
Where the facts come from
- Ahvaytum (en.wikipedia.org)
- PBDB Taxon (paleobiodb.org)
- Rethinking dinosaur origins: oldest known equatorial dinosaur-bearing assemblage (mid-late Carnian Popo Agie FM, Wyoming, USA) (dinodata.de)
- Ahvaytum bahndooiveche | Dinosaur Database by DinoAnimals.com (dinoanimals.com)
- Dinosaurs roamed the northern hemisphere millions of years earlier than previously thought, according to new analysis of the oldest North American fossils – UW–Madison News (news.wisc.edu)
- Ahvaytum in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.
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