Help with Laos tooth ID (Spinosaurid?)

[DinoFossilsUK]

Hi!  I have a tooth from the Gres Superieurs formation of Laos and I'm struggling with the ID.  The person I acquired the tooth from suggested it was an undescribed spinosaurid - possibly Baryonychinae - due to the striations in the enamel.  I'm not sure though, so I was hoping someone with more knowledge of teeth from Loas might be able to help me out.

 

My first thoughts upon seeing the tooth were that it was likely to be a Pterosaur or fish tooth.  It's certainly not Ichthyovenator as it's far too narrow.

 

It's 0.88 inches long.  Thanks in advance for any help!

IMG_6481.HEIC IMG_6482.HEIC IMG_6483.HEIC

[Fin Lover]

Pictures in that format won't open. Can you please upload them directly to your post?

[Fossildude19]

They need to be in .png or .jpg format.

[DinoFossilsUK]

Oops! Sorry about that!

[Dino Dad 81]

No denticles?

[DinoFossilsUK]

1 hour ago, Dino Dad 81 said:

No denticles?

I don't think there are any visible, but then it's fairly worn

[Troodon]

Could be a Spinosauridae, Ichthyovenator is described from there.  Ronan (2014) believes its a Spinosaurinae with straight unserrated teeth.  Not a lot published but like to see something if someone has info lets see it.

Do you have a locality identifies it being from that Formation versus one from Thailand.

 

[DinoFossilsUK]

On 9/26/2022 at 7:05 PM, Troodon said:

Could be a Spinosauridae, Ichthyovenator is described from there.  Ronan (2014) believes its a Spinosaurinae with straight unserrated teeth.  Not a lot published but like to see something if someone has info lets see it.

Do you have a locality identifies it being from that Formation versus one from Thailand.

 

Very sorry, I didn't see your response.  I believe its Savannakhet Province - I know the individual who traded me this tooth has other teeth from that formation too so I have no reason to question its provenance.  I guess it's a possible Spinosaurid then.  But out of interest, what would make you rule out the possibility of Pterosaur or fish in this case?  

[Troodon]

We know very little so anything is possible.  The vertical ridges support spinosaurid but the curvature is a unknown.

Some similarity to ridges in Thailands Siamosaurus

 

[Dino Dad 81]

I recently saw a big KK Spinosaurus tooth for sale from what I believe to be a reputable dealer and it had significantly more curvature, primarily  in the proximal portion of the tooth, than I've seen before. Almost to a Plesiosaur extent (be clearly a Spinosaurus tooth). They were ID'ing it as a premax . If so, I'd have to imagine it was one of those large teeth in the very front. If it really was what it was ID'ed as, it suggested that Spinosaurus had a good deal more positional variation than I realized--and I've got a ton of Spinosaurus teeth. I've seen lots of positional variation in the curvature of Suchomimus teeth too.

 

I mention this because my inexperienced suspicion is that the degree of curvature here doesn't work against a spinosaurid ID.

[DinoFossilsUK]

Yes, the ridges look very similar to those Siamosaurus teeth.  And I've also seen a lot of variation in Kem Kem spino teeth, some with very distinct curvature, so I guess it's perfetcly possible it's a Spinosaurid.  As always, thanks for enlightening me!