50 Million Year Old Knightia Fish Fossil – Green River Formation

Step back approximately 50 million years with this authentic Knightia eocaena Fish Fossil from the famous Green River Formation near Kemmerer, Wyoming. Dating to the Eocene Epoch, this beautifully preserved fossil offers an extraordinary glimpse into an ancient freshwater ecosystem that flourished long before humans ever walked the Earth.

During the Eocene, the Green River region was covered by vast subtropical lakes surrounded by lush vegetation and rich wildlife. Knightia was one of the most common fish species inhabiting these calm freshwater environments, swimming in large schools through warm waters and feeding on small aquatic organisms. Closely related to modern herring and sardines, Knightia played an important role within this thriving prehistoric ecosystem.

This authentic fossil was discovered in a quarry approximately 20km outside Kemmerer, Wyoming — an area internationally recognised for producing some of the finest fossil fish specimens in the world. After the fish died, it drifted gently to the quiet lakebed where it was rapidly buried beneath ultra-fine sediment. Low oxygen conditions prevented scavenging and slowed decomposition, preserving delicate skeletal structures and fine anatomical details with remarkable clarity.

Over millions of years, these sediments compressed and hardened into the fine-grained limestone that made the Green River Formation world famous for its exceptional fossil preservation. Today, fossils from this formation provide scientists with one of the most detailed records of ancient freshwater ecosystems ever discovered, helping researchers better understand prehistoric climates, lake environments, and the evolution of early fish species.

This authentic Knightia fossil is more than a collector’s specimen — it is a beautifully preserved snapshot of prehistoric freshwater life frozen in stone for millions of years.

The Details You Need — Forever Gems Fossil Facts

✓ SPECIMEN: Fossil Fish
✓ SPECIES: Knightia eocaena
✓ AGE: Eocene Epoch (Approx. 50 Million Years Old)
✓ FORMATION: Green River Formation
✓ LOCATION: Near Kemmerer, Wyoming, USA
✓ SPECIMEN SIZE: 137mm x 71mm x 5mm Approximately
✓ FISH SIZE: 99mm x 34mm Approximately
✓ WEIGHT: 106 grams
✓ PRESERVATION: Natural fossil fish preserved in fine-grained limestone
✓ AUTHENTICITY: Genuine prehistoric freshwater fossil specimen
✓ DISPLAY: Ideal for fossil collections, educational displays, and natural history décor

Own a genuine piece of Earth’s ancient freshwater history and let this extraordinary Knightia fossil bring the prehistoric lakes of the Eocene into your collection.