Dinosaur tooth ? Which one ?

[Coco]

Here is a tooth my colleague found a lot of years near Cognac (Charente, France). It is from a sedimentary facies Purbeckian (Late Jurassic, Lower Cretaceous). The quarry was in the marl, we found many reptiles, teeth and fish scales there, and of very small shark teeth.

 

 

 

 

The size is 4 cm (1" 3/5)

 

Thanks for your help.

 

Coco

[Ramon]

Wow!!! It is a theropod tooth. Resembles a tyrannosaurid tooth. Not sure!!! 

[jpc]

The photos are quite good and I don't see any serrations.  Could this be a large marine reptile?   By the way... 'career' is supposed to 'quarry'.  'Carriere' en francais a deux sens... 1) le boulot qu'on a (t'a carrierre est clown,) et 2) un trou pour ramasser des cailloux.  'Career' en anghlais c'est le boulot.  

[Coco]

Hi JP,

 

You are right   It was in a quarry !

 

I have just looked at it with a binocular microscope and there is no track of dentation, just a hull (keel ?) on a single side. It isn't maybe a reason to exclude a carnivore ?

 

Coco

[Vieira]

I don't see a serration neither.

 

I think if it not have a serration, the best shot it's a marine reptile tooth indeed...

 

 

[Troodon]

Definitely not dinosaurian.  Let me offer two possibilities.   A crocodyliform from the Purbeckian facies called Goniopholis but I'm not sure if they became that large 

 

 

Another possibility since the Quarry appears to be marine is the Metriorhynchidae called Dakosaurus.  It's found in the late jurassic early cretaceous deposits and the size fits. 

 

[oilshale]

This Dakosaurus from the upper Jurassic of Painten (Painten Formation, almost same age as Solnhofen) is on display in the foyer of "Kalkwerke Rygol", owner of the quarry and producer of drymix mortars.

 

The largest Dakosaurus tooth from there is 11cm !!!

 

PS: Not me!

[Ridgehiker]

13 hours ago, Coco said:

Hi JP,

 

You are right   It was in a quarry !

 

I have just looked at it with a binocular microscope and there is no track of dentation, just a hull (keel ?) on a single side. It isn't maybe a reason to exclude a carnivore ?

 

Coco

 

Neat specimen. Always good to see something different.

 

I have found unworn T rex teeth without a hint of serrations. However, they dont have such a pronounced axial line.  Usually more subtle.  This doesnt rule out dino but not likely. It has a terrestrial coc look but I'm unfamiliar with marine teeth.