Montana Cretaceous shark tooth ID

[bthemoose]

The tooth below is listed for sale as Cretodus crassidens from the Carlisle Shale in Montana. While there might be some very slight wrinkles on the labial side of this tooth, this doesn't look like the typical lingual or labial enamel folds that I would expect from Cretodus, so I'm wondering if it might be from Cretalamna or something else instead.

 

@siteseer, @ThePhysicist, @Anomotodon, any thoughts on this one?

 

The slant length of the tooth is 22 mm. Photos are from the seller, slightly cleaned up by me.

 

 

 

 

Edited October 10, 2021 by bthemoose
Fixing photos

[siteseer]

Hi B,

 

That's an Archeolamna tooth.  Right, Cretodus would have more distinct folds especially at the crown foot on the labial face, and the main cusp and cusplets would taper more.  I have seen weak folds like that on a tooth from the Judith River Formation, Blaine County site, MT.  Also, Archeolamna has a dental band which stays around the same height just like on that tooth.  Did you get a locality - even a general one?

 

Jess

[fossilselachian]

Agree with Jess_

[bthemoose]

3 hours ago, siteseer said:

Hi B,

 

That's an Archeolamna tooth.  Right, Cretodus would have more distinct folds especially at the crown foot on the labial face, and the main cusp and cusplets would taper more.  I have seen weak folds like that on a tooth from the Judith River Formation, Blaine County site, MT.  Also, Archeolamna has a dental band which stays around the same height just like on that tooth.  Did you get a locality - even a general one?

 

Jess

 

Thanks, Jess! It’s from Garfield County, MT.