The fossil of an ancient marine reptile stored in a Doncaster museum for 30 years had been mistaken as a plaster model!
Dean Lomax from the University of Manchester
came upon this plaster copy of an ichthyosaur fossil in 2008, in the collections of the Doncaster Museum and Art Gallery in the U.K when he realized it wasn’t a cast at all- it was actually the 189-million-year-old remains of an ichthyosaur. Often misidentified as "swimming dinosaurs", this creature, known for its sharp, robust teeth, swam the oceans for millions of years during the Triassic, Jurassic, and Cretaceous. And so, together with his team, they’ve examined the "forgotten" fossil for over five years.
After thorough studies, they found that not only it was real, it was also different. Several features of the limb bones (the humerus, forefin, and femur) and the shoulder (or pectoral girdle) were completely unlike any other ichthyosaur known. “That became very exciting,” Dean says in a news release
. “After examining perhaps over a thousand specimens we found four others with the same features as the Doncaster fossil.” The fossil likely belonged to a subadult animal or older.
It’s the most complete ichthyosaur of this age and was especially so well preserved that the contents of its stomach is still determinable. “We could see tiny hook-shaped features that were actually the hooks from the tentacles of squid," he tells BBC
. "So we know what its last meal was." They also suspect that there are certain differences in the humerus between males and females of this species for in some groups of reptiles (both living and extinct) different limb bones can be noticed in males and females.
How it was eventually mistaken for a copy isn’t really clear. Nonetheless, they named it Ichthyosaurus anningae
in honour of Mary Anning, the British fossil-hunter who began collecting ichthyosaurs in the early 1800’s. “Mary and her brother, Joseph, discovered the first ichthyosaur specimen to be scientifically recognized, collected at Lyme Regis around 1811,” Dean adds