10" Diplomystus With Cockerellites Fossil Fish - Wyoming

This is a pair of beautifully preserved fossil fish from the 18 inch layer of the Green River Formation. There is a 10" Diplomystus dentatus right next to a 5.4" Cockerellites (Priscacara) liops. They are both presented on a 11.5x10.5 slab of shale which has been backed for stability and has a wall hanger installed.

About The 18 Inch Layer Of Fossil Lake

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.

About Fossil Lake

50 million years ago, in the Eocene epoch, 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
Diplomystus dentatus & Cockerellites (Priscacara) liops
LOCATION
Kemmerer, WY
FORMATION
Green River Formation, 18 Inch Layer
SIZE
Diplomystus 10", Rock 11.5x10.5"
CATEGORY
ITEM
#144041
GUARANTEE
We guarantee the authenticity of all of our specimens.