A suite of five ancient crocs, including one with teeth like boar tusks and another with a snout like a duck's bill, have been discovered in the Sahara by National Geographic Explorer-in-Residence Paul Sereno.

The five fossil crocs, three of them newly named species, are remains of a bizarre world of crocs that inhabited the southern land mass known as Gondwana some 100 million years ago.

Many of the fossils were found lying on the surface of a remote, windswept stretch of rock and dunes. The crocs galloped and swam across present-day Niger and Morocco when broad rivers coursed over lush plains and dinosaurs ruled.

"These species open a window on a croc world completely foreign to what was living on northern continents," Sereno said. The five crocs, along with a closely related sixth species, will be detailed in a paper published in the journal ZooKeys and appear in the November 2009 issue of National Geographic magazine.

At 40 feet in length and weighing 8 tons, Sarcosuchus imperator, popularly known as SuperCroc, was the first and largest of the crocs Sereno found in the Sahara, but it was not the strangest, Sereno said.

He and his teams soon discovered key fossils of five previously unknown or poorly understood species, most of them walking "upright" with their arms and legs under the body like a land mammal instead of sprawled out to the sides, bellies touching the ground.

"Paleontologist Paul Sereno with his Saharan discoveries - SuperCroc, BoarCroc (upper right), PancakeCroc (lower right), RatCroc, DogCroc and DuckCroc. The fossil crocs were unearthed in a series of expeditions to the Sahara beginning in 2000, supported by the National Geographic Society. (Credit: Photo by Mike Hettwer, courtesy National Geographic)"

Source: National Geographic Society