Plesiosaur/Elasmosaurid tooth? Found in North Sulphur River, TX

[bluefish1766]

Hi all

 

My son and I were looking through some teeth from the NSR and want to get your opinions on this one. We first thought that this was a mosasaur tooth; however, someone suggested that it may be a plesiosaur/elasmosaurid tooth.  We wanted to gather some more opinions since we have no idea what it is.  The tooth measures 16 x 6 x 6 mm.

 

Thanks and Happy New Year!

[pachy-pleuro-whatnot-odon]

Hard to say, as I'm not all too familiar with American mosasaur species, but I see where this suggestion is coming from. However, I do make out what appears to be a cutting edge, or carina, on the first, third and fifth photographs. This is not a characteristic of plesiosaur teeth, especially not as it runs in a bit of twist (i.e. not straight down), thereby creating a distinct labial and lingual surface in the same way most mosasaur teeth do (cf. Mosasaurus hoffmannii):

 

Mosasaurus hoffmannii from Wikipedia.

 

Initially, the striations present at the base of the tooth kind of threw me off, as this can indeed be indicative of plesiosaur. But with the smooth labial surface seen in the first photograph, I'd say this is definitely mosasaur and likely some variant of Platecarpus sp. - which at least in Morocco has these kind of folds at the base:

 

 

Just for sake of comparison, here's some online image that were identified as NSR plesiosaur teeth.

 

[Coco]

Hi,

 

Oh Pachy ! It is forbidden to put a link of an online shop or of a seller ! Please delete your links

 

Coco

[pachy-pleuro-whatnot-odon]

Thanks for the heads-up, @Coco! Probably did read it in the rules at some point, but will pay more attention to it in the future.

[bluefish1766]

Thanks so much, Pachy!  I've looked at the tooth again and compared it to the other mosasaur teeth and agree with you.  There is definitely a carina running along the leading edge.  From the photos of the plesiosaur teeth, there isn't a carina like you said.  

 

What do you think of this tooth?  It was also found in the North Sulphur River.  It's very worn, and one half is missing.  Someone said that it is a Protosyphyraena tooth.  Though missing half of the tooth, it's broad and flat.  There appears to be a carina.  

[pachy-pleuro-whatnot-odon]

Hi @bluefish1766,

 

Unfortunately, I'm not too familiar either with NSR-fossils (have never gone hunting there myself, though I did acquire a couple of pieces from that location) or with teeth other than those of the three groups of largest Mesozoic marine reptiles: ichthyosaurs, plesiosaurs and mosasaurs. As this second tooth looks nothing like plesiosaur or mosasaur, I'd say fish tooth is probably right. But whether it's Protosyphyraena sp. or something else, I really wouldn't be able to tell you. Doesn't look like Enchodus sp. to me (as it is rather a broad tooth and lacks the necessary curvature), but rather reminds me of the teeth you'd find on a modern sawfish rostrum (so not Onchopristis sp.), if that's any help.

[pachy-pleuro-whatnot-odon]

Just found this post on the forum. I see some superficial semblances:

 

 

[bluefish1766]

Thanks so much for all the info, Pachy!  I'm going to make a post on this tooth and see what others think as well.  These fossils are endlessly fascinating!

[pachy-pleuro-whatnot-odon]

On 7/7/2020 at 4:59 AM, bluefish1766 said:

Thanks so much for all the info, Pachy!  I'm going to make a post on this tooth and see what others think as well.  These fossils are endlessly fascinating!

No problem! Hope somebody else on this forum will be able to help you further And, you said it: I too find these fossils endlessly fascinating!