Newly discovered fossilized remains of lepidosaurs, the ancient kin of lizards, snakes and tuatara, are the oldest yet to be found and provide evidence that the creatures were living some 240 million years ago in the Middle Triassic period.
The two new fossils predate the oldest known lepidosaurs by 12 million years, according to research published in the journal BMC Evolutionary Biology.
The fossils, both jaw bones, provide evidence that the lepidosaurs first appeared after the mass extinction event at the end of the Permian era, a period marked by a humid climate.
"The Middle Triassic represents a time when the world has recovered from the Permian mass extinction but is not yet dominated by dinosaurs. This is also when familiar groups, such as frogs and lizards, may have first appeared," said study author Marc Jones of the University College London.
Based on the small teeth and light build of the fossilized jaw bones, Jones and his colleagues suspect the ancient creatures fed on small insects. The fossilized creature is most closely related to the modern day tuatara, a lizard-like reptile endemic to islands around New Zealand. Tuatara are the lone survivors of an animal group that was once as globally widespread as lizards are today.
The lepidosaurs fossils were located in Vellberg, Germany. Further examination of them may shed new light on fauna that lived before dinosaurs dominated the Earth. The site may continue to yield more fossil specimens and broaden the vertebrate fossil record.
"The fossil record of small animals such as lizards and frogs is very patchy. Hopefully, this new fossil site in Germany will eventually give us a broader understanding of what was going on at this time," said study co-author Susan Evans.