Martinectes
Martinectes was a small, fast-swimming marine reptile that lived in the shallow seas of North America during the time of the dinosaurs. It had a short neck, a long snout, and four big flippers that helped it chase after fish and squid.1
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Fun facts
Martinectes was one of the smallest adult polycotylid plesiosaurs ever found, measuring only about 2.3 to 2.6 metres long.1
It had large eyes with a bony ledge above them, which may have shaded its eyes from sunlight while hunting near the water's surface.1
Martinectes lived about 80 million years ago in the Western Interior Seaway, a huge ocean that split North America in two.1
Its name means 'Martin's swimmer', honoring the person who helped discover its fossils.1
Martinectes was originally thought to be a species of Dolichorhynchops, but scientists gave it its own genus in 2024.1
It had unusually wide bones in its spine and a very short back part of its skull, which helped scientists tell it apart from other plesiosaurs.1
Most asked questions about Martinectes
?How big was Martinectes?
Martinectes was a large polycotylid plesiosaur, measuring at least around 5 metres (16 ft) long. Some estimates suggest it could reach up to 6 to 7 metres (20 to 23 ft), while a 2026 estimate put it at about 4.95 metres (16.2 ft) long.2
?Was Martinectes a dinosaur?
No, Martinectes was a plesiosaur, a marine reptile that lived in the seas during the time of the dinosaurs. It was not a dinosaur.2
?What did Martinectes eat?
Martinectes likely chased after fish and squid, using its long snout and four big flippers to swim fast. Its small teeth and narrow jaws suggest it ate small, slippery prey.2
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For dino experts
- Scientific name
- Martinectes
- Named by
- Clark et al. 20243
- Group
- Plesiosaurs
- Family / clade
- Polycotylidae3
- Classification
- Plesiosauria > Sauropterygia3
- Age of the rocks
- 84 to 72 million years (Campanian)3
- Rock formations
- Pierre Shale, Taylor Marl3
- Countries
- USA3
- Fossil records
- 3 in the Paleobiology Database3
- Discovery
- Martinectes was named in 2024 by Robert O. Clark, F. Robin O'Keefe, and Sara E. Slack. They studied fossils that had been found in Wyoming and South Dakota, USA, and realized they belonged to a new genus.31
- Still debated
- Scientists are still debating exactly how Martinectes used its unusual eye ledges and wide skull for hunting.1
Where the facts come from
- A new genus of small polycotylid plesiosaur from the Upper Cretaceous of the Western Interior Seaway and a clarification of the genus Dolichorhynchops (sciencedirect.com)
- Martinectes (en.wikipedia.org)
- Martinectes in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.
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