Astephus
antiquus
Class: Actinopterygii,
Order Siluriformes, Superfamily Ictaluroidea,
Family Ictaluridae
Gosiutichithys parvus
Class Actinopterygii, Order Clupeiformes, Family
Clupeidae
Geological
Time: Middle Eocene
Size (25.4
mm = 1 inch): Astephus: 197 mm long Gosiutichthys: 55 mm-110 mm long
Matrix: 370 mm by 290 mm by 32 mm thick
Fossil
Site: Green River Formation, Laney Member, Lake Gosiute, Current
Creed Ranch, Rock Springs, Wyoming
Fossil Code:
AW65
Price: $2250.00
Description:
There are numerous locations worldwide that are noted for wondrous
preservation of bony fishes, and the Green River formation that
covers some 25,000 square miles of SW Wyoming, western Colorado
and eastern Utah is one of the premier examples. The formation
is one of the largest lacustrine sedimentary accumulations in
the world, and spans the period from 40 to 50 million years ago
during the Eocene Epoch. During that time period there existed
three different
lakes of various extent and duration: Fossil Lake, Lake Gosiute,
and Lake Uinta. While Fossil Lake gets most
of the attention, there are fine examples from the other sites
as well, such as this death assemblage from Lake Gosiute. The
largest specimen is the Ictalurid catfish Astephus
antiquus. It is quite complete. Along with Hypsidoris, they form
the earliest
examples of the Ictaluridae. Based upon mouth shape they both
probably preyed upon smaller fish, crayfish and mollusks much
like the members of the family do today. The Aspetphus is surrounded
by a constellation of a dozen Clupeids known as Gosiutichthys.
When first described in 1980 they were referred to as Knightia
cf alta, but there were sufficient differences to erect the new
genus Gosiutichthys. Like Knightia, they are sometimes found
in vast rafts of examples which died in some massive fish kill.
This specimen was collected some years ago on private land and
has recently become available. This massive plate would make
an excellent display item. There is one repaired crack which
passes through the center of the piece, but the joining of the
halves renders it almost invisible.
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