Huge, 20.7" Fossil Fish (Phareodus) - Exceptional Specimen!

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This is a enormous and darkly preserved, 20.7" long Phareodus fish from the famous 18 inch layer of the Green River Formation in Wyoming. It's nicely centered on a 37 x 26.9" slab of shale and the preservation is dark and detailed. This specimen has been backed with wood and upon request, can have a french cleat style wall hanger installed at no additional charge.

There is a crack that runs across this rock and through the fish. This crack required repair and restoration where portions of the fish chipped away.

Phareodus is a genus of predatory freshwater fish found in the famous Fossil Lake deposits of the Green River Formation in Wyoming. It had a mouthful of sharp pointy teeth, making it a voracious lake predator. In fact, the name Phareodus actually means "to have teeth". Spines from other fish such as Mioplosus and Priscacara have frequently been found preserved in their stomachs.

Specimens like this come from the coveted 18 inch layer of the Green River Formation, which produces darker and more detailed fish than the majority on the market. The rock from this layer is much harder and more durable than other layers in the formation, likely due to its initial deposition conditions in deep water. Because of these conditions, fish found in the 18-inch layer can be extracted whole and in excellent condition. This layer is typically collected at night using low-angle light to see the bump in the rock that the fish's backbone creates. They then cut these fish out and take them to a lab where the fish, which may be up to an inch under the surface of the rock, are meticulously extracted under microscope with hand tools.

A view of the 18 inch layer of the Green River Formation at the Lindgren quarry near Kemmerer, Wyoming.
A view of the 18 inch layer of the Green River Formation at the Lindgren quarry near Kemmerer, Wyoming.

50 million years ago, in the Eocene, these fish thrived in Fossil Lake, which was fed by the Uinta and Rocky Mountain highlands. 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: 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.

A view of one of the commercial quarries where fossils from the Green River Formation are collected.
A view of one of the commercial quarries where fossils from the Green River Formation are collected.
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DETAILS
SPECIES
Phareodus testis
LOCATION
Kemmerer, Wyoming
FORMATION
Green River Formation, 18 Inch Layer
SIZE
20.7" fish on 37 x 26.9" shale
CATEGORY
ITEM
#144007
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