Forgotten Fossil Of The "Melksham Monster" Sheds Light On The Evolution Of Crocodiles


Tom Hale

Senior Journalist

clockOct 4 2017, 10:26 UTC

The Melksham Monster closely resembled the species shown (Plesiosuchus manselii), which also belongs to the Geosaurini group. Illustration by Fabio Manucci

The fossilized remains of "The Melksham Monster” have been laying around in the backrooms of the Natural History Museum in London since 1875. After being largely ignored for the past century and a bit, scientists have recently found out this ancient reptile is much more interesting than previously thought.

Palaeontologists from the University of Edinburgh in Scotland discovered this specimen belongs to a new species of prehistoric marine predator that is a distant relative of the modern crocodiles. They also revealed that this extinct group of aquatic reptiles evolved millions of years earlier than was previously thought, as explained in their recently published study in the Journal of Systematic Palaeontology


The fossil was called the “Melksham Monster” for decades, referring to the English town of Melksham where it was discovered. Now, it has the much more professional-sounding (although less catchy) name of Ieldraan melkshamensis

This ancient reptile stalked the shallow seas that covered current-day Europe around 163 million years ago. The species would have grown to around 3 meters (10 feet) from snout to tail and likely lived on a diet of large prehistoric squid.

"The Melksham Monster would have been one of the top predators in the oceans of Jurassic Britain, at the same time that dinosaurs were thundering across the land," explained study author Dr Steve Brusatte from the University of Edinburgh's School of GeoSciences.

Part of the Melksham Monster fossil, including a close-up of one of its distinctive teeth on the lower jaw. Davide Foffa

This new research focused on the specimen’s distinctive features of its skull, lower jaw, and teeth. The new species belongs to the sub-family of prehistoric crocodiles known as Geosaurini. It was previously thought that this sub-family originated in the Late Jurassic period, between 152 and 157 million years ago. However, the latest discovery and other re-analysis of existing fossil evidence indicate that the group arose millions of years earlier in the Middle Jurassic.

"It's not the prettiest fossil in the world, but the Melksham Monster tells us a very important story about the evolution of these ancient crocodiles and how they became the apex predators in their ecosystem,” added lead author Davide Foffa, a PhD student at the University of Edinburgh's School of GeoSciences.

These discoveries did not come easily, however, largely due to the condition of the fossil.


Mark Graham, Senior Fossil Preparator at the Natural History Museum, said: "The work took many hours over a period of weeks, and great care had to be taken to avoid damaging the skull and teeth as they became exposed. This was one tough old croc in life and death!"

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  • evolution,

  • jurassic,

  • crocodile,

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  • sea creature,

  • crocodilian,

  • sea monster,

  • crocodylomorphs