This Specimen has been sold.
1.75" Hoploscaphites Ammonite - Pierre Shale, Montana
This is a bumpy, 1.75" Hoploscaphities crassus ammonite specimen collected from the Pierre Shale of Montana.
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.