Scientists have uncovered remains of the biggest snake ever known at the site of an ancient South American rain forest in Colombia.
Titanoboa cerrejonensismeasured 13 metres, weighed as much as a small car, and had a body more than a metre thick.
The monster relative of the boa constrictor lived in northern Colombia 60 million years ago.
Palaeontologist Dr Jonathan Bloch, from the University of Florida at Gainesville, US, who co-led the expedition to Colombia, said: "Truly enormous snakes really spark people's imagination, but reality has exceeded the fantasies of Hollywood."
The 1.27-tonne snake could only have grown so large if temperatures at the equator were hotter than they are now.
Scientists estimate that a cold-blooded serpent of
Titanoboa'ssize would have required an average annual temperature of 30C to 34C (86F to 93F) to survive. By comparison, the average yearly temperature in the Colombian coastal city of Cartagena is about 28C (82F).
"The discovery of
Titanoboachallenges our understanding of past climates and environments, as well as the biological limitations on the evolution of giant snakes," said Dr Jason Head, from the University of Toronto in Canada, one of the authors who described the find today in the journal
Nature.
Titanoboa'senormous vertebrae were discovered by Dr Bloch's team in the Cerrejon coal mine in northern Colombia, along with fossilised plant material from the oldest known rain forest in the Americas.
Fossil bones of giant turtles and extinct crocodiles, which may have been the snake's prey, were also found.
"Prior to our work, there had been no fossil vertebrates found between 65 million and 55 million years ago in tropical South America, leaving us with a very poor understanding of what life was like in the northern Neotropics," said Dr Bloch. "Now we have a window into the time just after the dinosaurs went extinct and can actually see what the animals replacing them were like."