Double 6" Diplomystus Specimen - Wyoming

Double Diplomystus Specimen - Wyoming #13097

This is a piece of shale from the Green River Formation containing a pair of 6" long Diplomystus dentatus. It was collected from the "18 inch layer" at Warfield's Quarry near Kemmerer, Wy. Both fish are nicely detailed and this piece would be perfect for framing and display. The matrix is 10.5x10.2" and about 3/4" thick but we can trim the plate down a little smaller upon request.

Fossil fish from the 18 inch layer split out "ghosted" underneath the surface of the rock. Typically only bumps from the back bone can be seen in faint relief against the surface of the rock. Because of this they typically collect this layer at night using high powered lighting which allow them to better see the shadows from these bumps on the rock. These fish must then be prepared removing all of the matrix from on top of them, a very meticulous and time consuming process. While, like most fish from the 18 inch layer there is some minor touchup restoration work, but the fish has not been painted and is it's natural color.

About Diplomystus

Diplomystus is an extinct genus of freshwater, ray-finned predators that are distantly related to modern herrings and sardines. Diplomystus has a distinctive jaw that protrudes aggressively outward from the mouth at an angle that allowed it to feed in surface waters and devour such prey as the smaller, schooling Knightia.

50 million years ago in the Eocene (55.8 mya to 33.8 mya), D. dentatus thrived in lakes fed by the Uinta and Rocky Mountain highlands. D. dentatus is uniquely entombed in the fine-grained lime mud of Fossil Lake.

The anoxic conditions at the bottom of Fossil Lake slowed bacterial decomposition, prevented scavengers from disturbing corpses, and, most interestingly, suffocated creatures that ventured into the oxygen-starved aquatic layer. The result is a miraculous exhibition of Eocene biota in a subtropical aquatic community within sycamore forests, teeming with creatures such as freshwater stingrays, dog-sized horses, menacing alligators, early flying bats, and one of the first primates.

By the end of the Eocene, Earth developed icehouse climate characteristics and had a change in atmospheric chemistry. The effects of bolide impacts may also have contributed to the eventual loss of flora and fauna at once verdant latitudes.

Today the wonderfully preserved fossils of Diplomystus and other Fossil Lake fauna are collected in several private quarries around Kemmerer, Wyoming. The best preserved fish fossils come from the coveted 18 Inch Layer. This layer is collected at night under high-powered lights, enhancing the faint signs of fish under the surface indicating underlying fossils. These “ghosted” fish then must go through many hours of manual preparation to remove the overlying rock and reveal the Green River fauna in all of its glory.