Museum Green River Fish Fossils Aspiration

Mioplosus eating Knightia

Mioplosus labracoides

Class Actinopterygii, Order Perciformes, Family Percidae

Knightia eocaena

Class Actinopterygii, Order Clupeifomes; Family Clupeidae

Geological Time: Eocene

Size: Fish fossil Overall: 131 mm Mioplosus: 120 mm in length on a 147 mm by 80 mm matrix

Fossil Site: Split Fish Layer, Green River Formation, Fossil Lake, Kemmerer, Wyoming

Code: WFF162

Price: Sold

Museum Green River Fish Fossils AspirationDescription: This 50 million year old, Eocene-Era fossil fish comes from one of the world's famous Laggerstatte, 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. The rich brown color shows this one comes from the famous Split Fish Layer, a name derived from the fact that the deposits from which these excellent specimens are quarried tends to split along the axis in which the fossil is found. These beds can be several meters in thickness as contrasted with the 18 Inch Layer whose name is indicative of the total thickness of this deposit.

This one is known as an “aspiration”, a name given such specimens in that the fish died while choking on its prey, here a small Knightia. A few specimens such as this are found each year, and are highly prized by collectors. I was fortunate to acquire this one and one other at this year’s Tucson fossil show.

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, just as this one. It may be related to the modern-day pike of the genus Stezostedion.

Fossils Sales Information

click fossil pictures to enlarge

Fossil Mall Navigation:
l Home l Fossils for Sale Map l Museum and Rare Fossils l How to Buy Fossils l

Navigate by Fossil Category:
l Trilobites
l Ammonites l Fish Fossils l Invertebrate Fossils l
l Crinoids and Echinoderms l Insect Fossils l Dinosaur and Reptile Fossils l
l Cambrian Explosion Fossils l Plant Fossils l Stromatolites l
l Vertebrate Fossils l Fossil Amber l Trace & Ichnofossils l

l Fossils and Paleotological Science Information l