Pahasapasaurus
Pahasapasaurus was a fast-swimming marine reptile that lived in the ancient seas of North America. It had a long snout and paddle-like flippers to chase fish and squid.12
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Fun facts
Pahasapasaurus was a plesiosaur, not a dinosaur. It was a marine reptile that lived in the ocean.1
Its name comes from the Lakota words 'Paha Sapa', meaning 'Black Hills', where the first fossil was found.1
The first specimen was discovered in 1934 by Charles Haas and his son Arthur while they were looking for shark teeth.1
Pahasapasaurus had a long snout and a mouth full of many similar teeth, perfect for grabbing slippery fish.2
Its flippers were long and paddle-shaped, and the bones in the lower part of the flipper were longer than wide, which helped it swim fast.1
The fossil was once covered in shellac and sugar sacks, and scientists had to carefully clean it to study the bones.1
A second species of Pahasapasaurus was named in 2025 from a complete skull found in Utah.1
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- Scientific name
- Pahasapasaurus
- Named by
- Schumacher 20073
- Group
- Plesiosaurs
- Family / clade
- Polycotylidae3
- Classification
- Plesiosauria > Sauropterygia3
- Age of the rocks
- 100 to 94 million years (Cenomanian)3
- Rock formations
- Greenhorn Limestone3
- Countries
- USA3
- Fossil records
- 1 in the Paleobiology Database3
- Discovery
- Pahasapasaurus was named by Bruce Schumacher in 2007. The first fossil was found in 1934 by Charles Haas and his son Arthur in South Dakota, but it took many years before scientists realized it was a new species.1
- Still debated
- Scientists are still debating exactly how fast Pahasapasaurus could swim and whether it hunted alone or in groups.1
Where the facts come from
- Pahasapasaurus (en.wikipedia.org)
- PBDB Taxon (paleobiodb.org)
- Pahasapasaurus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.
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