Funky gastropod. May be Anchura turricula?

[rawfossils]

From the Rocky Ridge Sandstone unit of the Pierre Formation near Fort Collins, Colorado

[Crusty_Crab]

I am not familiar with that species, but it is very consistent with the genus Anchura that I have encountered. For reference, this is a representative from the Cretaceous of California, Anchura (Helicaulax) tricosa Saul and Popenoe, 1992:

 

[rawfossils]

On 12/23/2022 at 11:26 AM, Crusty_Crab said:

I am not familiar with that species, but it is very consistent with the genus Anchura that I have encountered. For reference, this is a representative from the Cretaceous of California, Anchura (Helicaulax) tricosa Saul and Popenoe, 1992:

 

 

Thank you that is definitely it. You have a very well preserved arm on that one but it looks like the same thing as this one.