Below are examples of the types of fossils that can be found in the Wyoming Green River Formation. Some types are more common and some more rare, but each piece is unique. If you are interested in purchasing, or taking a tour of where they are found, please call, email, or stop by.
Diplomystus DentatusThis is the second most common fish in Fossil Lake. Other smaller fish preserved in their stomachs or stuck in their mouths indicates that fish was a part of their diet. This fish could grow up to 24 inches long.
Knightia Alta and EocaenaThe eocaena is the most common of the two in Fossil Lake and may very well be the most common articulated vertebrate fossil in the world and is also the Wyoming state fossil. This fish grows up to 10 inches long.
Phareodus encaustus and testisMany sharp teeth indicate that this fish was a fish eater. In fact, remains of Knightia, Mioplosus, and some Priscacara have been found in both encaustus and testis breeds. Even though the testis is half the size, it is still considered a formidable predator as well.
Heliobatis Radians (fresh water stingray)This is the only species of ray found in the Green River Formation. They have been found to be as large as 30 inches long.
Cardiospermum Coloradensis ( fresh water crayfish)(rare)This fresh water crayfish is a relative of the modern crayfish and could grow up to 6 inches but like the shrimp is not found as easily as the some of the fish are.
Aspiration(rare)An aspiration is when a fish tries to eat a smaller fish and dies.There are two explanations for the aspirations. One is that the fish trying to eat a smaller one was caught in a volcanic eruption and died on the spot and was covered with sediment. However the best explanation is that the fish tried to "bite off more then they could chew" and choked to death, and fell to the bottom of the lake then got covered up in sediment.
Mioplosus LabracidesThis fish has been found commonly with other fish in it's mouth and one specimen was found with a knightia half its size in it's mouth. This fish grows up to 20 inches long.
Priscacara liops and serrataThe liops and serrata had rounding crushing teeth and ate shrimp, crayfish or ostracods. The serrata grew much larger than the liops breed. Liops grew to 6 inches, Serrata grew to 17 inches
Phylum Arthropoda (fresh water shrimp or prawn)(rare)Could grow up to 6 inches in lenth and is a very close ancestor of the shrimp we know of today.
Eohiodon Woodruffi(very rare)This fish fed mostly on insects and lived mostly in streams which may explain it's rarity in Fossil Lake.This fish could grow up to 12 inches long.
Besides Green River Fossils, we also offer a selection of other kinds of fossils from all over the world, like this Ammonite half from Madagascar and more! Come see us to find out what’s in stock!