Fox Hills Shark Tooth: ID Requested

[Thomas.Dodson]

I've collected another Fox Hills shark tooth and I wanted to see if anyone more familiar with Maestrichian shark species has any ideas on what it may be. Attached is a preliminary list of species present in the Fox Hills of North Dakota as reported from Hoganson in 1995. There have been additional species discovered since that are present in a recent publication but I don't currently have access to that paper. I do have experience with some of these from other Cretaceous deposits but I welcome input from anyone with ideas.

Pictures of the specimen. It has been difficult to get clear pictures due to the size. The incomplete root also complicates things but it is rare enough to warrant a try at identification. The shape and direction of the blade, lack of cusps (it seems complete enough to make this determination) and general stoutness makes me think something along the lines of Paranomotodon but that's just a guess on current information.

Labial surface

Lingual surface

 

 

 

[Al Dente]

It could be a broken Carcharias samhammeri. Image from this site-https://www.cretaceousatlas.org/species/carcharias-samhammeri/

 

 

[Notidanodon]

based on the faunal list provided, i would go with Carcharias tenuiplicatus 

[Thomas.Dodson]

38 minutes ago, Al Dente said:

It could be a broken Carcharias samhammeri. Image from this site-https://www.cretaceousatlas.org/species/carcharias-samhammeri/

 

 

Ah, that's one of the species from the other publication I'm looking for. Very interesting. My eyes might be fooled and the lack of cusps could very well be from damage.

 

15 minutes ago, will stevenson said:

based on the faunal list provided, i would go with Carcharias tenuiplicatus 

The stoutness of the blade does fit with Carcharias more. I've since seen Paranomotodon toddi described from the Fox Hills of ND (also on Cretaceous Atlas) and the blades are more slender than Paranomotodon angustidens (ignoring potential differences in teeth positions), which was my only reference before. As I mentioned my eyes might be fooled and the lack of cusps could be wear or damage.

 

I've since seen multiple teeth images from Cretaceous Atlas that are from the 2019 Hoganson publication. It just makes me want to see it even more.

[Thomas.Dodson]

For those interested I have obtained the 2019 publication thanks to @Mainefossils and C. tenuiplicatus is only known from a former site in Logan county (mostly destroyed) and a site in Bowman county. C. samhammeri seems to quite widespread and is the most abundant shark tooth recorded in the Fox Hills of North Dakota.