99-Million-Year-Old Snake Hatchling Found Encased in Burmese Amber
The fossilized remains of an embryonic-to-hatchling snake have been found preserved in Cretaceous amber from Myanmar (also known as Burma).
The newly-reported specimen was obtained from an amber deposit in the Angbamo area in Myanmar’s Kachin province.
The fossil is a 1.6-inch (4.75 cm) long postcranial skeleton made up of 97 vertebrae; the snake’s head is missing. It dates from the Late Cretaceous period, approximately 99 million years ago.
“This snake, named Xiaophis myanmarensis, is linked to ancient snakes from Argentina, Africa, India and Australia,” said University of Alberta’s Professor Michael Caldwell.
“At 99 million years old, it dates back to the age of the dinosaurs, well before snakes started to differentiate into modern groups,” added Dr. Alessandro Palci, from Flinders University and the South Australian Museum, Australia.
“This Asian fossil helps shed light on how primitive snakes dispersed from the southern to the northern continents.”
“Although found in the northern hemisphere, it strongly resembles South American snakes that lived at the time.”
The amber fragment in which Xiaophis myanmarensis was found also provided important clues about its environment.
“It is clear that this little snake was living in a forested environment with numerous insects and plants, as these are preserved in the clast,” Professor Caldwell said.
“Not only do we have the first baby snake, we also have the first definitive evidence of a fossil snake living in a forest.”
About 150 million years ago (Late Jurassic epoch), Myanmar was joined to Australia, Antarctica, Africa and South America, forming the supercontinent Gondwana.
Through continental drift, Myanmar eventually separated from Gondwana and drifted north, until it collided with Asia.
“Xiaophis myanmarensis was part of the fauna that rode on this drifting landmass, which like a gigantic passenger ship transported all sorts of Gondwanan plants and animals to Asia,” said Professor Michael Lee, also from Flinders University and the South Australian Museum.
“In fact, even though this snake was found in the northern hemisphere it resembles Gondwanan snakes.”
Along with Xiaophis myanmarensis, the team found and studied a second piece of amber with what appears to be a fragment of shed skin from a much larger snake.
“The scales of the snake are diamond-shaped or ovoid diamond-shaped, with deep lines formed by skin between each scale. Some rows converge as observed ventrally in extant snakes,” the scientists said.
“No enlarged ventral scales can be observed. Light and dark areas distributed across the shed skin reveal color patterning.”
The degree of preservation allowed the researchers to model the pigmentation pattern of the animal in life.
The research is published in the journal Science Advances.
Lida Xing et al. 2018. A mid-Cretaceous embryonic-to-neonate snake in amber from Myanmar. Science Advances 4 (7): eaat5042; doi: 10.1126/sciadv.aat5042