What is this Cretaceous sea creature?

[Creek - Don]

I found this fossil at DFW creek tonight. Was at the lower Cretaceous Dallas Austin Chalk sediment.   I saw someone posted this similar one on this fossil forum, but forgot the name of it. 

[DPS Ammonite]

It looks like a poorly preserved coiled cephalopod steinkern. Do you see any septa?

[Creek - Don]

Thanks DPS.  No I didn't see any septa anywhere on this fossil. 

[Fossildude19]

Nautiloid?

[JohnJ]

FYI - the Austin Chalk is all Upper Cretaceous.   

[Creek - Don]

Sorry, I meant to say very end of upper Cretaceous where Austin Chalk sediment has almost ended.  

[Heteromorph]

Looks like a nautilid from the Austin Chalk, specifically from one of the “Blue Rock” beds. The obviousness of the septa can be pretty sketchy in the Austin Chalk, especially in the Blue Rock, but from what I can see the morphology all points to nautilid.

 

As for narrowing it down to a genus, according to Keith Minor upper Cretaceous nautilid taxonomy is kinda confusing right now and there probably need to be more papers published to sort out messes, so this is as specific as I can go. 

[Creek - Don]

Great job identifying nautilid guys. Finding almost complete nautilid is exciting.     I have found plenty of ammonites in both broken form or in complete pieces.  

[JamieLynn]

I found one almost exactly like this in Austin Chalk, in Austin a few weeks ago. My tentative ID (and not an expert here, just doing my best) is Eutrophocerisis campbellii