15.3" Multiple Fossil Fish (Diplomystus & Knightia) Plate - Wyoming

This is a 15.3" wide fossil fish plate collected from the Lindgren Quarry at the Green River Formation of Wyoming. The shale contains three total fish, one of the species Diplomystus dentatus, and the other two are Knightia eocaena. They come out of the 18 inch layer (bottom cap) which produces beautifully preserved fish, but takes 2-3x longer to prep. The Diplomystus is 7.3" long and the Knightia measure 5.3" and 3.7" long.

This specimen is accompanied by a display stand.

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.
FOR SALE
$575
DETAILS
SPECIES
Diplomystus dentatus & Knightia eocaena
LOCATION
Lindgren Quarry, Kemmerer, Wyoming
FORMATION
Green River Formation - 18 Inch Layer (Bottom Cap)
SIZE
Shale: 15.3 x 9.8", Largest Fish: 7.3" long
CATEGORY
ITEM
#292364
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