Discovered: The turtle the size of a SmartCar - which would have hunted crocodiles in prehistoric lakes

Discovered: The turtle the size of a SmartCar - which would have hunted crocodiles in prehistoric lakes - Picture a turtle the size of a Smart car, with a shell large enough to double as a children's pool.

Paleontologists from North Carolina State University have found just such a specimen – the fossilised remains of a 60-million-year-old South American giant that lived in what is now Colombia.

The turtle in question is Carbonemys cofrinii, which means 'coal turtle', and it is part of a group of turtles known as pelomedusoides.

The specimen's skull measures 24 centimeters, and the shell, which was recovered nearby and is believed to belong to the same animal - measures 172 centimeters, or about 5 feet 7 inches, long.

Taking a bite out of a croc: The 'coal turtle' would have a large territory based around a lake - and he could tackle small crocodiles with ease

Ironically, that's the same height as Edwin Cadena, the NC State doctoral student who discovered the fossil.

The fossil was named Carbonemys because it was discovered in 2005 in a coal mine that was part of northern Colombia's Cerrejon formation.

Dr. Dan Ksepka, NC State paleontologist and research associate at the North Carolina Museum of Natural Sciences, believes that this is because a turtle of this size would need a large territory in order to obtain enough food to survive. Ksepka said: 'It's like having one big snapping turtle living in the middle of a lake.

'That turtle survives because it has eaten all of the major competitors for resources. We found many bite-marked shells at this site that show crocodilians preyed on side-necked turtles.

'None would have bothered an adult Carbonemys, though - in fact smaller crocs would have been easy prey for this behemoth.'

Cadena said: 'We had recovered smaller turtle specimens from the site. But after spending about four days working on uncovering the shell, I realized that this particular turtle was the biggest anyone had found in this area for this time period - and it gave us the first evidence of giantism in freshwater turtles.'

Easily mistaken? Carbonemys cofrinii was about the same size as this green Smartcar

Smaller relatives of Carbonemys existed alongside dinosaurs.

But the giant version appeared five million years after the dinosaurs vanished, during a period when giant varieties of many different reptiles – including Titanoboa cerrejonensis, the largest snake ever discovered – lived in this part of South America.

Researchers believe that a combination of changes in the ecosystem, including fewer predators, a larger habitat area, plentiful food supply and climate changes, worked together to allow these giant species to survive. Carbonemys' habitat would have resembled a much warmer modern-day Orinoco or Amazon River delta.

Giant turtle! Lonely George, the last giant turtle from the Galapagos Islands, is alive and well but possibly the last of his kind - his shell measures 102cms

In addition to the turtle's huge size, the fossil also shows that this particular turtle had massive, powerful jaws that would have enabled the omnivore to eat anything nearby – from mollusxcs to smaller turtles or even crocodiles.

Thus far, only one specimen of this size has been recovered.

The paleontologists' findings appear in the Journal of Systematic Palaeontology. Dr. Carlos Jaramillo from the Smithsonian Tropical Research Institute in Panama and Dr. Jonathan Bloch from the Florida Museum of Natural History contributed to the work.

The research was funded by grants from the Smithsonian Institute and the National Science Foundation. ( dailymail.co.uk )

---