Two Fossil Ammonites (Discoscaphites) - South Dakota

This is a 4.1" wide section of rock that contains a Discoscaphites gulosus ammonite and a Discoscaphites conradi ammonite, collected from the Fox Hills Formation of South Dakota. Unlike many ammonite associations from this location, neither of these ammonites have been remounted to the rock. There are two bonus, partially exposed ammonites within the rock, however they are unidentified.

It is accompanied by an acrylic display stand to assist with presentation.

These 70 million year old ammonites lived when South Dakota was a shallow inland sea. It was found preserved in a concretion that was split open. It then had to be hand prepared to remove the hard rock surrounding it from the shell, a very time consuming task.

Ammonites were predatory mollusks that resembled a squid with a shell. These cephalopods had eyes, tentacles, and spiral shells. They are more closely related to a living octopus, though the shells resemble that of a nautilus. True ammonites appeared in the fossil record about 240 million years ago. The last lineages disappeared 65 million years ago at the end of the Cretaceous.

Discoscaphites gulosus & Discoscaphites conradi
North Central, South Dakota
Fox Hills Formation
Ammonites: 1.35" & 1.3", Rock: 4.1 x 2.5" rock
We guarantee the authenticity of all of our
specimens. Read more about our
Authenticity Guarantee.