Fossil of Lengthy and Slender-Snouted Ichthyosaur Uncovered in England

University of Manchester paleontologist Dean Lomax and his colleagues have recognized a brand new genus and species of leptonectid ichthyosaur from a fossilized specimen present in Dorset, England.

The almost full skeleton of a dolphin-sized ichthyosaur was discovered close to Golden Cap in 2001 by Dorset fossil collector Chris Moore.

The specimen features a cranium with huge eye socket and an extended sword-like snout, and represents a brand new genus and species.

The fossil dates again to the Pliensbachian age of the Early Jurassic, between 193 and 184 million years in the past.

“I remember seeing the skeleton for the first time in 2016. Back then, I knew it was unusual, but I did not expect it to play such a pivotal role in helping to fill a gap in our understanding of a complex faunal turnover during the Pliensbachian,” Dr. Lomax mentioned.

“This time is pretty crucial for ichthyosaurs as several families went extinct and new families emerged, yet the new species is something you might call a ‘missing piece of the ichthyosaur puzzle’.”

“It is more closely related to species in the later Early Jurassic, and its discovery helps pinpoint when the faunal turnover occurred, being much earlier than expected.”

“It is the first described genus of an Early Jurassic ichthyosaur described from the region in over 100 years.”

Named Xiphodracon goldencapensis, the brand new ichthyosaur would have been about 3 m (10 ft) lengthy and would have dined on fish and squid; the stays even present what could also be traces of its final meal.

“This skeleton provides critical information for understanding ichthyosaur evolution, but also contributes to our understanding of what life must have been like in the Jurassic seas of Britain,” mentioned Dr. Erin Maxwell, an ichthyosaur skilled on the State Museum of Natural History Stuttgart.

“The limb bones and teeth are malformed in such a way that points to serious injury or disease while the animal was still alive, and the skull appears to have been bitten by a large predator — likely another much larger species of ichthyosaur — giving us a cause of death for this individual.”

“Life in the Mesozoic oceans was a dangerous prospect.”

The authors recognized a number of options in Xiphodracon goldencapensis which have by no means been noticed in any ichthyosaur.

The most peculiar is an odd and distinctive bone across the nostril — known as a lacrimal — that has prong-like bony constructions.

“Thousands of complete or nearly complete ichthyosaur skeletons are known from strata before and after the Pliensbachian,” mentioned Professor Judy Massare, an ichthyosaur skilled on the State University of NY at Brockport.

“The two faunas are quite distinct, with no species in common, even though the overall ecology is similar.”

“Clearly, a major change in species diversity occurred sometime in the Pliensbachian.”

“Xiphodracon goldencapensis helps to determine when the change occurred, but we still don’t know why.”

The study was revealed this month within the journal Papers in Palaeontology.

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Dean R. Lomax et al. 2025. A brand new lengthy and narrow-snouted ichthyosaur illuminates a fancy faunal turnover throughout an undersampled Early Jurassic (Pliensbachian) interval. Papers in Palaeontology 11 (5): e70038; doi: 10.1002/spp2.70038