A fearsome, prehistoric, sea monster's jaw complete with terrifying club-shaped teeth – designed to crush turtles - has been found in Texas

The jaws of an ancient sea predator have been discovered in northeast Texas, adding to a very rare collection of bones from a species that ruled the oceans 80 million years ago

Unearthed by a private fossil collector, the jaws of the Globidens alabamaensis – a 20ft long mososaur – were discovered in a thin, fossil-rich deposit embedded in the North Sulphur River near Ladonia, Texas.

One of the jaw fragments holds 12 teeth, while the other holds six – each roughly an inch long. In one of the jaws, a germ tooth remains below the gumline. Scientists believe that, like sharks, mosasaurs shed their teeth and replaced them throughout their lives.

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What’s unique about the teeth of this species of mosasaur is the bizarre shape. While mosasaurs like the Mosasaurus maximus had sharp teeth designed for larger prey, G. alabamaensis had blunt, globular teeth, likely designed for crushing shelled animals, like turtles and ammonites.

What were mosasaurs?

Co-existing with the dinosaurs (but not dinosaurs themselves) 80 million years ago, mosasaurs were among the ocean's most fearsome and successful predators.

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Mosasaurs had a long serpentine body, a powerful tail and paddle-like limbs. Its large head had powerful, flexible jaws.

Across the mosasaurs group the teeth differed and were specialised to their prey – as evidenced by the recently discovered jaws of the G. alabamaensis.

Mosasaurs were highly adaptable and many different species evolved to dominate ocean habitats. However, alongside the dinosaurs, mosasaurs – including the mushroom-toothed G. alabamaensis – were wiped out during the mass extinction event at the end of the Cretaceous period.

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Main image: Reconstruction of Globidens alabamaensis Gilmore, 1912. Illustration by Nathan
Dehaut.

Researchers detailed the discovery of the two jaw bones in a paper published in the Journal of Paleontological Sciences on 14 August.