Description
This Fossil is a Hoploscaphites Ammonite Cephalopod. It is from the Cretaceous Period.
This spiral cephalopod still has some magnificent color but it is a small example.
A wonderful example of this Hoploscaphites Ammonite Cephalopod. Ammonites were marine creatures that lived in a hard shell. They were cephalopods related to octopus and Squid. But these creatures retained their hard shell. They can be found in large areas of South Dakota. Because of the erosion and weathering of the earth surfaces these can be readily found. But some rock breaking is necessary. Normally when found some shell material remains along with the color.
The Pierre Shale is an upper Cretaceous marine formation. And this formation is well known for its ammonite fossils. Much of the area in South Dakota was part of the Pierre Seaway. This was a sea that stretched out across the west. So this area was full of marine creatures including Mosasaurs and others. These Hoploscaphites Ammonite Cephalopod grew to large sizes but even the small ones have great detail.
The creature is related to the modern day octopus but then they had a hard external shell. However the octopus of today has lost their shells. The Ammonite also had tentacles with which it captured it’s food.
This Ammonite is 1 1/16 inch long and sits on an irregular matrix that is 4 1/4 by 2 3/4 inches.
