The oldest known snake fossils, dating from 143 million to 167 million years ago, have been uncovered.
Researchers, writing in the journal Nature Communications, say the fossils push back the first record of snakes by 70 million years.
Wile the snakes share recognisable features with modern snakes – including sharp, backward pointing teeth – their overall shape, length and body form still remains unknown.
Using a number of fossilised skull bones, Michael Caldwell in the Faculty of Science at the University of Alberta and colleagues identified four new species of snakes from England, Portugal and the US.
The snakes originated at a time when most other major groups of scaled reptiles were rapidly diversifying and that they existed in different parts of the globe in many different habitats including swamps, ponds, rivers and coastal systems.
“The study explores the idea that evolution within the group called ‘snakes’ is much more complex than previously thought,” says Professor Caldwell. “Importantly, there is now a significant knowledge gap to be bridged by future research as no fossils snakes are known from between 140 to 100 million years ago.”
Here’s one fossil:
The oldest known snake, from Southern England, near Kirtlington, Eophis underwoodi, is known only from very fragmentary remains and was a small individual.
The largest snake, Portugalophis lignites, from coal deposits in Portugal, near Guimarota, was bigger at nearly one metre or more in length.