29.8" Fossil Fish (Phareodus & Mioplosus) Plate - Wyoming

This is a darkly preserved, 12" long Phareodus testis and 9" long Mioplosus labracoides association, both of which are the more uncommon species of fish from this formation. This large specimen was collected from the famous 18 inch layer of the Green River Formation in Wyoming. The slab of rock they're on measures 29.8" wide by 14.7 tall.

This large fish plate has been backed with a wood board and has two ring hangers for a hanging presentation.

Phareodus had a mouthful of sharp pointy teeth making it a voracious lake predator. In fact the name Phareodus actually means "to have tooth". Spines from other fish such as Mioplosus and Priscacara have frequently been found preserved in their stomachs.


It comes 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. This layer is typically collected at night using low angle light to see the bump in the rock that the back bone 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.

50 million years ago, in the Eocene these fish thrived in Fossil Lake fed by Uinta and Rocky Mtn. 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 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.
Phareodus testis & Mioplosus labracoides
Kemmerer, Wyoming
Green River Formation, 18 Inch Layer
29.8 x 14.7" shale
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