Ptychodus mammillaris?

[bluefish1766]

Hi all

 

My son and I found this ptychodont tooth this morning at Post Oak Creek in Sherman, TX.  I think it's Ptychodus mammillaris; however, I also considered Ptychodus anonymous.  A photo (quarter for size comparison) is below.  I'd appreciate your thoughts.

 

Thanks!  

[ynot]

Can not help with id, but side and top views will help others. (straight on, not at an oblique angle.

 

Nice tooth whatever it turns out to be.

 

Tony

[bluefish1766]

Thanks, Tony.  Here are some other photos.

[ynot]

Much better pictures. Still need one straight down on the chewing surface.

By the way--WELCOME TO 

[bluefish1766]

Thanks again!  Here are two others.

[ynot]

Have You looked at this thread?

 

 

[LSCHNELLE]

It is pretty worn, so difficult to tell. I would say you are correct with P. mammilaris. P. anonymous probably does not get that large and P. latissimus has a lower crown height. 

[Chase B.]

Dear All, 

 

The specimen is the eroded tooth of a P. polygyrus from the Turonian Eagle Ford Formation.

 

 

Regards,

 

Chase

[LSCHNELLE]

My understanding per Shawn Hamm is that P. polygyrus does not occur in the USA - only in the Campanian of England/Europe.  It could be P. marginalis in the USA during Cenomanian or Turonian times.  But, no concentric ridges are visible.