Micro Reptile Tooth? From the Late Cretaceous of Texas

[Ramon]

Hi, I’ve recently been searching through some sifted gravel from a creek. I’ve been looking for microfossils, which I’ve had plenty of luck finding. All sorts of marine Cretaceous invertebrate micros are abundant in the creek gravel, as well as the occasional micro shark/fish tooth, scale, and bone fragment. 
I encountered a tooth that stood out from anything I’ve found so far. It has a conical shape, and is recurved. Something about this tooth seems very reptile-like. Almost looks like a tiny version of a crocodile or mosasaur tooth. The tooth measures 1 millimeter in length. 

I tried searching the internet for something similar, and have been unable to find something like this. 
The closest thing that I found was teeth from a jaw of a Coniasaurus that was found in North Texas. 

 

 

Here is the tooth that I found. It’s 1 millimeter from base to tip. 

 

The creek is located in Central Texas close to Austin, and passes through sediments spanning the whole Cretaceous geological column of Texas. From the Glen Rose Limestone to the Navarro Group. (~110-66 myrs). 
What do y’all think of this little tooth. Could it be from a small reptile like Coniasaurus and other dolichosaurs?

 

Edited September 3, 2022 by Ramon

[Jared C]

The only Dolichosaur recorded in North America is Coniasaurus crassidens.  That said, I don't think this is a Coniasaur tooth, it's not bulbous at the base of the crown and the enamel doesn't look right.

 

Here's a Coniasaur tooth, for comparison:

 

 

EDIT: I googled coniasaur tooth and this was the first image that came up that i recognized to be one. While yes, Coniasaur teeth look very much like this - this tooth comes from a mystery kansas dolichosaur:

https://www.researchgate.net/publication/232686348_A_unique_reptilian_large_dolichosaurid_lizard_tooth_from_the_Upper_Cretaceous_Niobrara_Chalk_of_western_Kansas

 

Edited September 3, 2022 by Jared C
elaboration

[Ramon]

1 minute ago, Jared C said:

The only Dolichosaur recorded in North America is Coniasaurus crassidens.  That said, I don't think this is a Coniasaur tooth, it's not bulbous at the base of the crown and the enamel doesn't look right.

 

Here's a Coniasaur tooth, for comparison.

 

 

 

True, it doesn’t look coniasaur-like, except for some of the front teeth of the jaw that was found near Dallas, which is supposedly said to be a possible new species. 
But I came across this paper titled “FOSSIL MARINE VERTEBRATES FROM THE LOWERMOST GREENHORN
LIMESTONE (UPPER CRETACEOUS: MIDDLE CENOMANIAN) IN
SOUTHEASTERN COLORADO”

The paper basically describes the diverse marine paleofauna of that formation in Colorado. It mainly focuses on microvertebrates, mostly teeth. 
My tooth doesn’t resemble any of the fish teeth. It does resemble some of the teeth in the reptilian section though, both in size and shape, which is why I wonder whether it could be a reptile tooth.

 

[Ramon]

Here’s a short video of the tooth under the microscope. 

[ThePhysicist]

54 minutes ago, Jared C said:

the enamel doesn't look right.

To be fair, it looks really weathered, but I agree the general shape doesn't match Coniasaurus all that well.

 

Despite the weathering, since it doesn't appear to be carinated, I would lean towards this being a fish tooth. Keep looking, I'm sure you'll find something more definitive!

[Jared C]

1 hour ago, Ramon said:

which is supposedly said to be a possible new species. 

I'm surprised that that leaked. There's not enough materiel to describe a new species based off of those features yet. Where did you hear that? If you don't mind me asking

[Ramon]

1 hour ago, Jared C said:

I'm surprised that that leaked. There's not enough materiel to describe a new species based off of those features yet. Where did you hear that? If you don't mind me asking

From the North Texas Fossils website