It began as a routine stroll along the windswept shores of Somerset, but for 11-year-old Ruby Reynolds and her father, a flash of bone among the stones at Blue Anchor was about to rewrite natural history. What they initially mistook for mere fragments turned out to be the jawbone of a prehistoric titan—Ichthyotitan Severnensis— the largest ever known marine reptile, stretching a staggering 82 feet from snout to tail.
The discovery was made in late May 2020 when the father-daughter duo were looking for fossils on the beaches. While recalling the incident, Justin Reynolds said that it was "bigger than any piece of bone I had ever found before."
The researchers have now identified Ichthyotitan severnensis as the largest known reptile that ever existed on earth.
How was the marine giant Ichthyotitan Severnensis discovered?
The photos captured by Ruby and her father were studied by palaeontologist Dean Lomax, who had initially identified it as an ichthyosauria, an order of large extinct marine reptiles.
The discovery acted like a final puzzle piece clicking into place. When these new fragments were compared with a jawbone discovered in 2016 by local collector Paul de la Salle, the true scale of the creature became apparent. Once reconstructed, the jaw spanned over 6.5 feet, confirming that both finds belonged to the same colossal, previously unknown species.
Formally named Ichthyotitan severnensis in the journal PLOS ONE, the species represents a new peak in prehistoric scale. Scientists used the massive jawbone to estimate a total body length of 82 feet, confirming that this 'giant fish-lizard' was nearly as long as a modern blue whale.
Palaeontologists described the fossils as "unusual and extremely large". They also noted that the reptile is "genuinely enormous, roughly the length of a blue whale."
The internal bone structure examination found evidence that the animal was still growing when it died.
Why is the discovery significant?
This discovery effectively redraws the map of the Triassic oceans. The creature's unique jaw structure and preserved physiological markers suggest a remarkably streamlined predator—one engineered for high-speed, long-distance pursuits across the vast, prehistoric deep.
Researchers also point out that the discovery highlights the rich fossil potential of the Somerset coastline.
The specimen offers the first clear evidence of a truly gigantic ichthyosaur from the Triassic era. It has set the stage for future breakthroughs, raising hopes that a complete skull or skeleton of this ocean-dwelling titan remains buried in the region, waiting to be unearthed.