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.
is one of the more rare of the Green River fish fossils, making
up some 1% of the total from Fossil Lake, its only known location.
Named by the famous 19th Century paleontologist E.D. Cope, the name
Amphiplaga is thought to mean "ambiguous wound", pointing
to the fact that the holotype specimen was headless.. Shaped rather
like a cross between a trout and a perch, the Percopsidae are colloquially
termed “trout perches”. Fossil percopsids are only known
from North America, the current home of the extant genus Percopsis.
With a maximum total length of 150 mm and an average of 100 mm this
is an average-sized adult specimen of this rarely offered taxon.
The two other items of interest in the upper and lower center are
a pair of coprolites (fecal fossils). The one at the top is a cast,
while the one below is a mold that shows both a fish scale and a