From the BBC:
"I rang up the county council and I said I think I've found a dinosaur," explained Joe Davis, who works at Rutland Water Nature Reserve.
During landscaping work at the reserve's reservoir in February 2021, he had spotted something odd poking out of the mud.
[…]
They concluded it was an ichthyosaur – a type of warm-blooded, air-breathing sea predator not unlike dolphins. They could grow up to 25 metres long and lived between 250 million and 90 million years ago.
Dr Dean Lomax, a palaeontologist from Manchester University, was brought in to lead the excavation effort. He called the discovery "truly unprecedented" and – due to its size and completeness – "one of the greatest finds in British palaeontological history".
I'm mildly disappointed that it's not an actual dragon … but holy shit, that is a very large creature.
Ichthyosaur: Huge fossilised 'sea dragon' found in Rutland reservoir [Jonah Fisher / BBC News]