What is this trace fossil?

[sharkysaurus]

Hi everyone! I recently found a trace fossil near my house. I live in Southeast Colorado Springs and there's a lot of marine fossils near where I live. I found what I believe is an ammonite trace fossil. I'm having some trouble identifying it though. I'm not exactly sure what ammonite it's from as well as what formation it's from and what type of stone it's in. I brought it in to the museum I volunteer at and it was determined by the curator that it is not sandstone and it's most likely from the Late Cretaceous. I think it might be from a Hoploscaphites cheyennensis in silt-stone from maybe the Pierre Shale formation(?) but I don't know! The rock is slightly porous, if that helps. Help would be appreciated! Thanks! 

 

[Thomas.Dodson]

It's a piece of a negative from an ammonite. You're probably on the right track with a scaphitid ammonite but without more of it and specific formation information it's unlikely you'll be able to ID it.

[doushantuo]

Welcome to the forum,Sharky

TD is correct on this one,I think

Those holes would be ornamental protrusions("BULLAE"),in Latin) before diagenesis

Edited October 16, 2021 by doushantuo

[doushantuo]

SHARKY,this is not meant a criticism,but I always try to put members on the path of the steepest learning curve humanly possible:

Trace fossil is generally used in the context of ichnology

edit: bypassing all geological dictionary definitions: 

the study of non-anatomical evidence for the existence of past life(think e.g. of traces of movement of animals

Edited October 16, 2021 by doushantuo