Multiple Specimen Mortality Plate

The Green River Formation in the USA covers an area over 25,000 square miles and is more than 2,000 feet thick. This formation, dates back more than 50 million years. It is one of the largest documented accumulations of sedimentary rock in the world. At the time, the area was sub-tropical and many different species flourished. Today, the majority of Fossil Fish taken out of this limestone formation are from two separate layers. "The 18" layer and the split fish layer". The 18" layer is composed of laminated sheets of limestone, allowing for fossil fish specimens to be extracted whole.

Priscacara (common name perch) is a member of the Family Prisca Caridae. The name Priscacara means "primitive head." The two Priscacara species are liops and serrata. Priscacara liops is the more common and the smaller of the two. The genus became extinct at the end of the Miocene period, and is thought to be related to the modern-day Cichlidae.