Scientists have identified a rare species of ichthyosaur, a prehistoric marine reptile, from a nearly complete skeleton discovered along the UK’s Jurassic Coast. The fossil, named Xiphodracon goldencapensis, a reference to its long, blade-like snout and dragon-like features, is the only known example of its kind. Experts say the ancient sword dragon sea reptile offers critical insight into an evolutionary gap dating back nearly 190 million years.
Unearthed near Golden Cap in Dorset in 2001 by local fossil collector Chris Moore, the dolphin-sized creature is the first new genus of Early Jurassic ichthyosaur described from the region in more than a century.
Preserved in three dimensions, the skeleton includes a large skull with a prominent eye socket and a sword-shaped snout. It measures roughly three meters in length and likely fed on fish and squid.
Rare discovery fills an evolutionary gap
Researchers believe the fossil is the most complete prehistoric reptile from the Pliensbachian stage, a period between 193 and 184 million years ago. Traces of its last meal appear to be present in the remains, and the skeleton itself shows signs of trauma.
Deformed teeth and limb bones suggest illness or injury during its lifetime. The skull also bears bite marks from what may have been a larger predator, possibly another ichthyosaur, indicating it may have died from an attack.
Meet the Sword Dragon of Dorset, Xiphodracon goldencapensis, an awesome new ichthyosaur we describe today! #fossilfriday
The world’s most complete Pliensbachian marine reptile.
Study: https://t.co/LTRkme6Fcl pic.twitter.com/LevijoLvz5
— Dr Dean Lomax (@Dean_R_Lomax) October 10, 2025
The specimen was later acquired by the Royal Ontario Museum in Canada, where it remained unstudied for years.
It has now been described in detail in the journal Papers in Palaeontology by an international team of paleontologists led by Dr. Dean Lomax, a research fellow at the University of Manchester and the University of Bristol.
Experts trace early marine evolution
Dr. Lomax said the fossil filled a missing piece in the ichthyosaur lineage, helping researchers pinpoint a significant shift in species diversity. This transition, known as a faunal turnover, occurred earlier than previously believed during the Pliensbachian, not later in the Jurassic as once thought.
Co-author Professor Judy Massare of the State University of New York at Brockport noted that while ichthyosaurs from periods before and after the Pliensbachian are common, this stage remains poorly understood. The discovery helps establish when the evolutionary shift occurred, though the reasons behind it are still unclear.
Dr. Erin Maxwell, from the State Museum of Natural History in Stuttgart, added that the fossil not only sheds light on ichthyosaur evolution but also offers a glimpse into marine life in Jurassic Britain.
The Xiphodracon skeleton will go on public display at the Royal Ontario Museum in Toronto.
