In May 2020, 11-year-old Ruby Reynolds made an extraordinary discovery on the shores of Somerset, England. What seemed like a typical day of fossil hunting with her father would soon reshape the understanding of prehistoric life forever. Ruby stumbled upon a fragment of bone unlike anything previously seen, and it wasn’t long before scientists realized they had uncovered a fossil from the largest marine reptile ever known to exist.
This creature, named Ichthyotitan severnensis, is believed to have measured an astonishing 82 feet long – comparable in size to a modern-day blue whale. The groundbreaking find was confirmed through a study published in PLOS ONE, revealing a new chapter in paleontological research.
The Discovery: A Moment of Serendipity
Ruby and her father, Justin, were no strangers to fossil hunting on the beaches near Blue Anchor, a site rich with ancient relics. But on that fateful day, the size and significance of their discovery surpassed anything they had encountered before. Justin recalls spotting a four-inch scrap of bone during their walk, saying,
“It was bigger than any piece of bone I’d ever found before.” He shared his find with Ruby, and as they continued their search, Ruby uncovered another bone fragment. “It was just sort of lying there,” she said. “I was just happy, really.”
Little did they know, the fragments would eventually prove to be part of a jawbone from a creature that roamed the seas over 200 million years ago.
A washed-up Ichthyotitan severnensis carcass on the beach.
Credit: Sergey Krasovskiy.
When the pair sent photographs of their find to paleontologist Dean Lomax, the excitement began to build. Lomax, who has worked extensively on marine reptiles, immediately recognized the potential of the fossils. “Of course, they were quite right,” Lomax said, confirming their identification. The bones belonged to an ichthyosaur, a type of marine reptile that once dominated the oceans during the Triassic period.
A Puzzle Comes Together
The story of the Ichthyotitan severnensis doesn’t stop with Ruby’s discovery. Scientists were already familiar with a partial jawbone found in Somerset in 2016. Lomax recalls how this earlier fragment, found by local collector Paul de la Salle, “fit together perfectly like an ancient prehistoric jigsaw puzzle.” When Ruby’s fossils were compared to the earlier find, it became clear that they belonged to the same species. The jawbones, once reassembled, revealed a size and structure far beyond the typical marine reptiles of the time.
The holotype of Ichthyotitan severnensis gen. et sp. nov., a newly collected specimen (BRSMG Cg3178) comprising a very large, but incomplete right surangular (the ‘BAS Specimen’)
A. All associated pieces with an approximate outline of the complete surangular, in medial view. The surangular is separated into two main parts, Part #A to the right and Part #B to the left (see text). B. A close-up of the coronoid process in lateral view, showing moderate eminence. C. Bulbous coronoid process in dorsal view with lateral displacement. D. Subcircular cross section at the level of the coronoid process (posterior view, medial to the left). E-F. Comparison of the massively developed M.A.M.E. ridge observed in BAS (E) and the Lilstock surangular (F); arrows indicate top of the ridge. G. Oblique view of the medial surface highlighting part of the overhanging shelf that encloses the Meckelian canal. H. Ventromedial view of the mid-posterior portion of the surangular showing a distinct, continuous, and straight thin groove that might be a suture and could indicate two distinct bones (perhaps including a damaged angular).
Lomax noted that this new discovery suggested that the creature was “unusual and exceedingly large.” The jawbone alone, which was over 6½ feet long, provided more than enough evidence to support the theory that Ichthyotitan severnensis was one of the largest animals to ever inhabit the seas. Its proportions hinted at an animal built for long-distance cruising in open waters, possibly surpassing even the size of today’s ocean giants, such as whales.
Comparison of the holotype (BRSMG Cg3178, A and C right surangular, BAS specimen) and referred specimen (BRSMG Cg2488, B and D left surangular, Lilstock specimen) of Ichthyotitan severnensis gen. et sp. nov. To ease comparison, A and C have been reversed.
A-B. Lateral view of both surangulars showing same unique shape; note the upturned, almost 90-degree angle bend and the spatulate-shaped posterior end. C-D. Medial view of both surangulars displaying same morphology posteriorly; anteriorly the Lilstock specimen (D) has been heavily eroded and distorted along its length (see Discussion in Lomax et al. 2018 for more details). Note the position of an elongated foramen on the lateral surface (A-B), identified as part of the fossa surangularis that passes through the bone into the Meckelian canal. See also the damaged (?)angular that is articulated with the surangular and defined by a continuous groove (?suture) as seen in Fig 2H.
Unveiling the Titan: What the Bones Reveal
Upon further study, paleontologists determined that Ichthyotitan severnensis could have reached lengths of up to 82 feet, making it a true leviathan of its time. This would make it the largest known ichthyosaur and a remarkable example of Triassic marine life. Lomax emphasized the creature’s sheer size, saying it was “genuinely enormous, about the length of a blue whale.” The bones also suggested a streamlined body adapted for life in the open ocean. Its skull, likely over 10 feet in length, and its paddle-shaped flippers may have given it the ability to traverse vast stretches of sea, hunting for squid-like cephalopods that were abundant at the time.
This discovery challenges previous assumptions about the Triassic oceans, revealing a rich and complex ecosystem teeming with life. It also highlights the remarkable adaptability of marine reptiles during this period, showcasing how evolution worked in the absence of larger predators, leaving room for creatures like Ichthyotitan to grow to such monumental sizes.
The Significance of the Find
The research, published in PLOS ONE, sheds new light on the ancient world of marine reptiles, providing invaluable insights into their growth patterns and evolutionary history. While much remains unknown about the Ichthyotitan species, Lomax and his colleagues are optimistic that further excavations might yield more specimens, potentially revealing even more about this giant creature.
“There were things that we can’t even possibly imagine in the past,” biomechanist Kelsey Stilson said. “But we can get little hints, and this is one little hint at this larger picture of evolution on Earth.”
With more fossils exposed each year due to erosion along the cliffs of Somerset, scientists remain hopeful that additional finds will continue to unlock the mysteries of ancient marine life. Each new discovery brings them closer to a full picture of these magnificent reptiles and the world they once inhabited.
