Priscacara, Green River Fossil Fish Ouranosaurus when they became extinct along

when they became extinct along with most of the Pleistocene megafauna

some estimates went up to 485 pounds

How cool is that

and four actual rib fragments in articulation with the vertebrae

each of which grew out of a separate spinal vertebra (a bone in the back)

Priscacara, Green River Fossil Fish Ouranosaurus when they became extinct alongThe genus Priscacara is perhaps the most popular of the Green River fish fossils. A member of the Family Priscacaridae, the name Priscacara means "primitive head". Shaped rather like a sunfish, the genus sports sturdy, protective dorsal and anal spines. Among the two species, liops and serrata, serrata is uncommon. Liops is the smaller species, never exceeding 6 inches, whereas serrata have been found up to 14 inches. The genus went extinct at the end