46" Wide Fossil Fish Plate (18 1/2" Diplomystus) - Wyoming

This is a large slab of shale, with two beautifully preserved Diplomystus fossil fish from the Green River Formation of Wyoming. It was collected from the famous 18 Inch Layer of Warfield's Quarry near Kemmerer, which produces detailed fish with very dark preservation.

The larger specimen on the piece is 18 1/2" long and the second Diplomystus is about 6" in length. The entire slab of rock measures 46x17", is about an inch thick and weighs 130 lbs. We've backed it with a concrete board to add extra support and allow for wall mounting hardware to be easily installed.

Due to the size and weight of the piece, it will need to be crated and shipped via freight. Freight shipping will be additional to the purchase price and will probably run around $300 within the continental US, but be substantially more for International shipping.

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.
Diplomystus dentatus
Warfield's Quarry, Kemmerer, WY
Green River Formation
Fish 18.5", 6" Long on 46.75x17.5" rock, 130 pounds
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