일반명 : 경골어류화석
학명(Name): Order: Order: Clupeifomes; Family: Clupeidae; Knightia eocaena
지질시대(Geological Time): 신생대 에오세(Eocene)
크기(Size) : 95 mm in length on 120 mm by 80 mm matrix (visible)
발견지(Location): Green River Formation, Fossil Lake, Kemmerer, Wyoming

Description: This 50 million year old, Eocene-Era fossil fish comes from one of the world's famous Laggerstatten, the Green River Formation in Wyoming. A small portion of the fish fossils from Green River exhibits such fine preservation. The significant extent of soft-tissue preservation that makes the site famous is evident in this specimen.
This particular fish is Knightia eocaena, the State Fossil of Wyoming. In Fossil Lake, these fish reach their maximum size of 25 cm, but averages roughly half that. Knightia was a schooling fish which is sometimes found in mass mortality layers confined to a single plane, indicative of a single event. Theories as to the reasons include stratified water turnovers as well as poisoning due to blooms of blue-green algae. The modern-day Alewife is known to do so in the Great Lakes of the US. This one is artistically displayed matted and framed, ready for hanging on the wall of the den or office of any fossil collector