Monster 15+ inch Diplomystus (18 Inch Layer)

This is an absolute monster of a Diplomystus at over 15 inches in length. It is from the 18 inch layer of the world famous Green River Formation exposed near Kemmerer, Wyoming. The detail on this fish is amazing, bone structure, fins, eye and robust backbone easily seen.

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 create. They then cut these fish out and take them to a lab where the fish which maybe up to an inch under the surface of the rock are meticulously extracted under microscope with hand tools.

Like essentially ALL fish from the 18 inch layer, there is some minor restoration to repair small bits of scale that flaked off during prep and on some fin tips (which typically don't preserve well)

It's a very impressive example of this predatory fossil fish.

Diplomystus is an extinct genus of freshwater, ray-finned predators that are distantly related to modern herrings and sardines. Diplomystus has a distinctive jaw that protrudes aggressively outward from the mouth at an angle that allowed it to feed in surface waters and devour such prey as the smaller, schooling, Knightia.

50 million years ago, in the Eocene (55.8 mya to 33.8 mya), D. dentatus thrived in lakes fed by Uinta and Rocky Mtn. highlands. A voracious predator and delicious prey, D. dentatus is uniquely entombed in the fine-grained, lime mud of Fossil Lake.

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.

By the end of the Eocene, Earth developed icehouse climate characteristics and had a change in atmospheric chemistry. The effects of bolide impacts may also have contributed to the eventual loss of flora and fauna at once verdant latitudes.

Today the wonderfully preserved fossils of Diplomystus and other Fossil Lake fauna are collected in several private quarries around Kemmerer, Wyoming. The best preserved fish fossils come from the coveted 18 inch layer. This layer is collected at night under high-powered lights allowing the faint signs of fish under the surface to be more easily observed. These “ghosted” fish then must go through many hours of manual preparation to remove the overlying rock and reveal the Green River fauna in all of it’s glory.
DETAILS
SPECIES
Diplomystus dentatus
LOCATION
Kemmerer, Wyoming
FORMATION
Green River Formation
SIZE
15.2"
CATEGORY
ITEM
#279
GUARANTEE
We guarantee the authenticity of all of our
specimens. Read more about our
Authenticity Guarantee.