Discovery at the Shore: Tourist Unearths Rare Fossil of the Oldest Known Sea Crocodile
A rock collector has uncovered an ancient fragment of bone belonging to one of the earliest known marine crocodiles. At first glance, the object appeared to be driftwood pierced with rusted nails. Only on closer inspection did its true identity begin to emerge.
The fossil - part of an upper jawbone - was discovered during a guided walk along the Lyme Regis coast in Dorset. Experts believe it may be one of just eleven known specimens from this ancient creature.
A Chance Discovery on the Beach
Heather Salt, from Solihull near Birmingham, had travelled to Lyme Regis hoping to add a small fossil to her personal collection.
"I really just wanted to find a little ammonite," she said.
While searching near an eroding section of beach scattered with debris, she noticed something unusual.
"It was by where there's an old dump eroding onto the beach, and there's lots of bits of metal, so I looked down and thought it was nails stuck into something."
Picking it up, she quickly sensed it was something different. Unsure, she showed it to fossil guide Casey Rich, whose reaction made the importance of the find immediately clear.
"He got so excited and just said - 'are you kidding me!' - and started calling everyone over."
Later, museum curator Dr Paul Davis confirmed the significance of the object.
"He came rushing over and said, 'that's croc!'"
Salt chose to donate the fossil to Lyme Regis Museum, recognizing its scientific value.
"I did find my own little ammonite in the end," she added.
Understanding an Ancient Marine Predator
The fossil is now displayed as part of the museum’s “Charmouth Crocodile” exhibit, originally discovered in 2017 near the nearby village of Charmouth.
Dr Paul Davis, a palaeontologist and geology curator at the museum, explained that such fossils offer rare insight into life in Jurassic seas around 200 million years ago.
Though often referred to as a marine crocodile, the creature actually belongs to a group called Thalattosuchia - ancient relatives of modern crocodiles adapted for life in the ocean.
Slender and streamlined, it could grow up to two metres long. Its narrow snout was specially shaped for catching fish, indicating a highly specialized hunting style.
Unlike modern crocodiles, these animals spent most of their lives in marine environments, only returning to land to lay eggs. Juveniles likely stayed near coastal areas before venturing further into open waters.
Why the Fossil Matters
According to Dr Davis, finds like this are extremely valuable because they come from a poorly understood period in evolutionary history.
"We've got a critical period of time where the crocodylomorph group were rapidly evolving, but we have no fossils. These are some of those critical fossils."
The discovery suggests that even 200 million years ago, these creatures were already highly adapted to marine life.
Studying the jawbone may also provide clues about feeding behavior and how early crocodile relatives developed their biting mechanics.
"We're getting these tantalising fragments," Davis said. "What we would love to find eventually would be a complete skull... that would help us solve some of the issues we have about their evolution and biology."
A Window Into Deep Time
The fossil also highlights the evolutionary link between ancient marine reptiles and modern crocodiles. Both belong to the broader group Crocodylomorpha, tracing their origins back hundreds of millions of years.
Despite surviving mass extinctions and dramatic environmental shifts, only certain branches of this lineage remain today.
Each new discovery adds another piece to the puzzle, helping scientists reconstruct how these ancient creatures lived, hunted, and adapted to their surroundings.
Conclusion
What began as a simple beach walk in search of a small ammonite turned into a rare scientific discovery. The fossil not only enriches museum collections but also deepens understanding of early marine reptiles.
Quiet fragments like this continue to reveal stories from deep time - showing how life evolved long before humans ever walked the Earth.