Priscacara, Authentic 5.75 Inch Green River Fossil Fish Troodon with 83 Clovis stone tools

with 83 Clovis stone tools

while the ammonites in this genus have uncoiled shells (heteromorph or different-shaped ammonites)

The Archaeonycteris species flew at moderate altitudes and speed

Differences from modern skulls include its more pronounced brow ridges

Priscacara, Authentic 5.75 Inch Green River Fossil Fish Troodon with 83 Clovis stone toolsThe 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