Fossil ignored in drawer pushes back reptile origin by 34m years

The fossilised remains of a small, sharp-toothed lizard, left in a cupboard for more than half a century, has pushed back reptile origins by tens of millions of years.

The specimen was collected in the 1950s from a quarry near Tortworth in Gloucestershire by the fossil hunter Pamela L Robinson. The creature was erroneously labelled before being stored, eventually ending up in the Natural History Museum in London.

Now researchers say advances in technology have allowed them to take a second look, revealing the specimen holds a pivotal position in the reptile family tree.

“It’s partly a story of neglected fossils in [a] drawer, and partially a story [that] without the CT scan, you would not have been able to do the work that we did,” said Prof Michael Benton, a palaeontologist at the University of Bristol and co-author of the study.

The long-tailed creature – which is about 25cm long – is thought to have lived around 202m years ago and has been given the name Cryptovaranoides microlanius. The first part means hidden lizard-like animal, referring to both its time spent unrecognised and probable concealment in rock crevices during its life. The second means “microbutcher”, a nod to the creature’s recurved blade-like teeth.

Using CT-scanning, Benton and colleagues were able to look at the fossil in fine detail and study the bones trapped within the rock.

He said the skull was 3cm in length, adding: “The fossil is tiny, the ribs are just minute.”

The results revealed the animal was a squamate – a group that encompasses creatures such as lizards and snakes. “They start out as lizards – snakes evolve rather later in the Cretaceous,” said Benton, referring to the period that lasted from about 145m to 66m years ago.

The creature has the hallmarks of modern lizards, such as modified bones at the back of skull that allow extra flexibility in jaw opening, making it the world’s oldest such reptile.

“It’s an anguimorph lizard – which today includes 350 species including everything from the gila monster of North America to the Komodo monitor,” said Benton.

The team said the finding pushed back the origins of modern squamates by at least 34m years. They added that the discovery had important implications for understanding the rate of evolution within the tree of life, and the timescale and triggers of biodiversity within modern squamates – the latter of which may aid conservation of living species.