The oldest ancestor of lizards has been found in England

The fossils were found on the coast of Devon County in south-west England back in 2015, but it took almost a decade to accurately classify them. The discovery is officially presented in the journal Nature.

The new species is named Agriodontosaurus helsbypetrae - in honour of the Helsby Sandstone Formation where it was found. The size of the palm of an adult man, the ancient lizard had amazingly large teeth, thanks to which could pierce and tear the shells of ancient insects, probably resembling modern cockroaches. Scientists speculate that it hunted in much the same way as the modern tuatara, the only living member of the beaked whale troop found in New Zealand.

"This creature is completely different to what we expected to see. Its skull has no hinges and a roof of teeth like modern lizards and snakes. What's more, it has a cheek to jaw bone structure that is unique to tuatara," explains palaeobiologist Dan Marquet of the University of Bristol, lead author of the study.

The Agriodontosaurus skull is only 1.5cm in size and was encased in large rock, which made the study difficult. Advanced equipment was needed for the study - British scientists sent the fossil to France, to the European Synchrotron Centre (ESRF), which uses X-rays 100 billion times brighter than those used in hospitals.

Using this technology, palaeontologists were able to create ultra-precise three-dimensional images and study the internal structure of the tiny skull in detail.

Agriodontosaurus is the oldest known member of the lepidosaurus order, which includes modern lizards, snakes and tuatara. Its unique anatomical features challenge established ideas about the evolution of these animals.

"The discovery has forced us to reconsider the evolutionary relationships between major reptilian groups. This is a rare chance to peer into the depths of the prehistoric world and understand how key features of modern species were formed," said Professor Michael Benton, co-author of the paper.