It was six times the length of human and had teeth that could crush turtle shells – and it was the largest marine crocodile ever to have lived.


That’s what scientists have concluded from the fossil of an extinct reptile unearthed in the Tunisian desert which they have called Machimosaurus rex.

The beast, which was 10.6 metres long and whose skull alone measured more than 1.5 metres, lived 130 million years ago in a shallow sea that is now North Africa.

Referring to its bullet-shaped teeth, University of Alberta Phd student Tetsuto Miyashita who contributed to the research, said: “These teeth weren’t for cutting or piercing flesh, they were built for crushing bones.”

Machimosaurus was originally uncovered by a joint Tunisian-Italian team of scientists in 2014. Federico Fanti, assistant professor at the University of Bologna and who lead that study, then contacted Miyashita via Skype to show him an image of the skull in the ground.

“There was a neck attached to it, and then the back, and the tail, and the limbs sticking out sideways,” Miyashita said. “The whole crocodile was there.”

“I could tell the whole length of the skull must be about my height, 5.5 feet. That’s larger than the skull of Tyrannosaurus rex.”


An illustration shows how Machimosaurus was roughly six times the length of a human.

But because of political instability in Tunisia, to date just the skull has been retrieved, and Fanti and Miyashita have been able to study it for only three days in the capital, Tunis.

“Sometimes we are reminded that our endeavor to unlock ancient mysteries is only possible through peace, freedom and the sheer goodwill of people,” Miyashita said.


Sarcosuchus imperator is usually cited as the largest crocodilian ever. It measured an estimated 11-12m and prowled riverbanks in what is now sub-Saharan Africa and South America 110 million years ago.


James FairWildlife journalist