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This very cool Green River Fossil Fish plague is a great addition to any collection.  The outstanding large fossil is a Diplomystus measuring 17 1/4″ from the mouth to the tip of it’s tail x nearly 6 1/4″ tall.   It shows extraordinary detail in the fossil skeleton and fins.  This awesome fossil is 100% original with no restoration or alterations.  The stunningly exceptional plaque weighs 17 pounds and measures almost 20 1/2″ wide x 13 1/8″ tall x 7/8″ thick.  A simply amazing specimen in a nice sized plaque for easy display makes it an even more interesting item.

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In southwest Wyoming (and parts of Colorado and Utah) in the Green River Formation are found some of the world’s most outstanding specimens of fossil fish.  The Green River system was composed of three lakes:  Lake Ulinta, Lake Gosiute and Fossil Lake.  These Eocene Lakes lay in a series of intermountain basins formed by geological events that uplifted the Rocky Mountains during the early Tertiary time.
The Climate was much different from the desert-like climate of this area today.  Both the fauna (crocodiles, alligators, boa constrictors and some subtropical fish families) and the flora (such as large palm trees) indicate a climate much like that found along the Gulf Coast today. 

The most common fish found in the formation is the Knightia, a herring-like fish.  They are found singularly or in large groupings. These groupings are referred to as “Mortality Layers” and are believed to have been caused by extensive ash fall-out after volcanic eruptions. Some of the other species of fish found in the Green River Formation are:  Phareodus, a carnivorous fish often found up to 2 feet in length and having many sharp teeth.  Mioplosus, a true perch, and Priscacara, a sunfish-like fish with stout dorsal and anal spines.  There are also turtles, stingrays, crocodiles and alligator gar-fish.

The fossils of the Green River Formation – each one unique – are some of nature’s finest art.  They are highly valued by collectors the world over.

Additional information

Weight20.00 lbs
Dimensions20.50 × 13.125 × 0.875 in

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