Extinct species

Mosasaurus

Mosasaurus hoffmannii Mantell, 1829

Taxonomy

Range: Western Europe and the Western Interior Seaway
Habitat: Marine habitats of the Cretaceous seas, including warm shallow continental waters.
Lived: Late Cretaceous · about 84–66 million years ago

Discovery: Was the very first mosasaur ever identified by scientists, discovered in a limestone mine in the 1770s.
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Size: Far more heavily built than other mosasaurs of similar length, roughly twice the weight.
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Diet: An apex marine predator with strong jaws suited to tackling large, armored prey.
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Trait: Had a double-hinged jaw, similar to some modern snakes, that may have helped it swallow large prey.
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Movement: Propelled itself with a powerful, shark-like tail fin rather than simple side-to-side undulation.
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Earth Context: One of the last and largest mosasaurs before the extinction that ended the age of giant marine reptiles.
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Time Context: Near the Cretaceous's close, its Maastrichtian type fossil came from Maastricht in what is now the Netherlands.
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Distribution: Its type material came from Maastricht in the Netherlands, in Maastrichtian rocks near the end of the Cretaceous.
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