Fossils of five exotic crocodiles that lived alongside the dinosaurs 100 million years ago have been found in the Sahara.

The newly-identified fossils were discovered at a number of sites on the surface of a remote and windswept stretch of rock and dunes in the Sahara desert on Thursday.

The ancient crocodiles include one sporting boar-like tusks and another with a duckbill snout.

''My African crocs appeared to have had both upright, agile legs for bounding overland and a versatile tail for paddling in water," Expedition leader Professor Paul Sereno from the University of Chicago described the finds in the National Geographic Magazine.

''Their amphibious talents in the past may be the key to understanding how they flourished in, and ultimately survived, the dinosaur era,'' he added.

Dr Hans Larsson, from McGill University in Montreal, Canada, who discovered the bones of 'BoarCroc' and 'PancakeCroc', said they were stunned by the discovery.

''We were surprised to find so many species from the same age in the same place," he said.

''Each of the crocs apparently had different diets, different behaviors. It appears they had divided up the ecosystem, each species taking advantage of it in its own way,'' he added.

''They may have had slightly more sophisticated brain function than living crocs, because active hunting on land usually requires more brain power than merely waiting for prey to show up,'' he further explained.

The animals' brains were studied by creating digital and physical casts from CT-scans and 3D X-rays.

HRF/MTM/DT