Name/Title
Mioplosus (Perch)Entry/Object ID
2011.57.5Description
Description: Family: Percidae
Genus: Mioplosus
Species: Osteichthtes
Common Name: Perch
Age: Eocene
Location: Green River Formation, Wyoming
Description: Rectangular slab with a single bony fish fossil. Very vivid detail. Beioge matrix with a brown fossil.
Physical Characteristics:
Mioplosus is an extinct genus of prehistoric bony fish that lived from the early to middle Eocene.
Very similar to today's perch, the Mioplosus is distinguished by its double dorsal fin and pointed teeth. It is thought to have been a solitary predator often attacking fish up to half of its own size. Mioplosus range from 2 to 20 inches but anything over 16 inches is very rare.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.Mioplosus labracoides is believed to have been a voracious predator among the Green River fish fossils. Failure to find its numbers in mass mortality leads to further conjecture that it was a solitary hunter. A member of the Family Percidae, it has numerous relatives in Northern Hemisphere fresh water as well as fossil relatives in Asia, Europe and New Zealand. It is known as a predatory species as determined from its many pointed teeth, and the fact that several have been found with fish lodged in its throat. It may be related to the modern-day pike of the genus Stezostedion.Distinguishing features include double dorsal fins and a fan-like tail. Mioplosus is uncommon in the Green River formation, especially the fish of this size.
Family: Percidae
Genus: Mioplosus
Kingdom: Animalia (Animals)
Class: Osteichthtes
Order: Perciformes
Phylum: ChordataCollection
Museum Collection of FossilsAcquisition
Accession
2011.57Source or Donor
Museum Collection of FossilsAcquisition Method
Long-term LoanDimensions
Width
5-1/2 inDepth
3/4 inLength
7-3/4 inLocation
Location
Container
LeftDrawer
Top ShelfShelf
Right, RightWall
NorthRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Steve MillerDate
July 13, 2011Location
Container
CenterDrawer
Top ShelfShelf
RightCabinet
Case # 48Wall
NorthRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
Permanent
