Help With Id Of Small Shark Teeth?

[ShadyW]

I posted this picture on another thread, but I'd really appreciate some help with IDs on some of the teeth:

The tooth top-left looks like a small Crow Shark tooth (Squalicorax?) and came from the North Sulfur River in Texas. The two barbed teeth on the far right also came from the NSR.

The rest of the teeth came from Post Oak Creek in Texas (although there's a small risk that a couple fo them are actually other NSR teeth).

I'm particularly interested in the beautiful tiny curved tooth bottom-left (a shark of some sort, but which?), the small conical tooth center-bottom (a very small croc, tiny Mosasaur or something else?), and the two barbed teeth on the far-right (barracuda or small sawfish rostrals?).

In a related question, the NSR teeth all came from a feature of the "red layer" clay that I don't understand. In some areas there are cylindrical features in the red clay layer which are ~4-6" diameter and the full thickness of the clay stratum. They are always circular when looked at from above, and extend through the clay layer from top to bottom. These "mini sink holes", as I think of them, consist of a darker gray clay matrix which is full of tiny fish bones, very small teeth and other very small (often broken) fossils. A couple of times I've found one or more large shark teeth in them too. Does anyone know what they are?

Edit: I'm trying to identify those I can from Elasmo.com.

The two middle-top look like Smalltooth Sand Tigers.

The two middle 2nd row look like Dogfish.

Although the tiny one bottom-left looks similar to the drawings of Lee Creek Catshark teeth, the root shape seems wrong.

[Xiphactinus]

I'll leave the sharks teeth to the experts on those.....

The long curved tooth on the far right looks to be an Enchodus fang

Your conical tooth on the bottom looks like a fish -- I would say probably Xiphactinus

[Northern Sharks]

The 2 you thought may be dogfish are not. To me, they look like they could be Pseudocorax. The Squalicorax looks correct, though I'm not too sure which species. The tiny one is a beauty, but again, I'm not too sure what it is, maybe Protolamna.

[ShadyW]

Thanks for your input. The more I look at pages like this the more I realize that identifying the great tooth in the lower-left may be very difficult indeed. Still, it's a really nice tooth!

In my view, the tooth lower-right is just as interesting, given that the strange shape is un-broken. The translucently-thin edges, the strange barb and the odd dagger-like shape really are like nothing I've ever seen before.

[ShadyW]

The 2 you thought may be dogfish are not. To me, they look like they could be Pseudocorax. The Squalicorax looks correct, though I'm not too sure which species. The tiny one is a beauty, but again, I'm not too sure what it is, maybe Protolamna.

Great feedback, thanks! Your ID for the tiny one really does look like a good match, and your Pseudocorax suggestion is a much better match than my "dogfish" ID.

[MB]

may be Pseudocorax granti and Carcharias heathi ?

[ShadyW]

I'll leave the sharks teeth to the experts on those.....

The long curved tooth on the far right looks to be an Enchodus fang

Your conical tooth on the bottom looks like a fish -- I would say probably Xiphactinus

GREAT ID on the Enchodus fang! That's it!

Not only does it have the s-shaped curve and the tiny barb, but I can feel the serrations on the leading edge, even if I can't see or photograph them!

[bierk]

You have a Sclerorhynchus sp. sawfish rostral tooth in the bottom right of the picture. I used to find those fairly regularly when I lived and hunted in texas. The one above it is definitely a fish of a different sort.

[ShadyW]

You have a Sclerorhynchus sp. sawfish rostral tooth in the bottom right of the picture. I used to find those fairly regularly when I lived and hunted in texas. The one above it is definitely a fish of a different sort.

Excellent! That's it! My picture's better than the one on Black River Fossils but it confirms the ID. I'm glad that my wild guess at a rostral tooth, based on the "root" shape, was on-target.

[Bill]

I think the bottom left shark tooth is a Sand shark symphyseal tooth.

The "sink holes" could be infilled crustacean burrows with the remains of their food.

Edit, what age are the POC fossils? Us foreigners (or at least myself) have no idea. Cretaceous?

[ShadyW]

I think the bottom left shark tooth is a Sand shark symphyseal tooth.

The "sink holes" could be infilled crustacean burrows with the remains of their food.

Edit, what age are the POC fossils? Us foreigners (or at least myself) have no idea. Cretaceous?

I believe that the Post Oak Creek site is part of the Eagle Ford Shale, making them Upper Cretaceous.

Oh, and I'm a Bloody Englishman too... I just happen to live in Texas! For many years I lived in central London before we emigrated.

[Bill]

[ShadyW]

Sorry I didn't mean to offend anyone, I was joking. Hence the brackets round (or at least myself).

??? You certainly didn't offend me! Whatever gave you that impression?

It takes one heck of a lot to offend me, and I'm quite certain that nothing on the Fossil Forums is going to over-step my offence boundaries!

[Bill]

[ShadyW]

I thought by your reply, "Oh, and I'm a Bloody Englishman too... I just happen to live in Texas," that I had offended you.

Hmm. Perhaps I shouldn't call myself a Bloody Englishman. How about Wingeing Pom, Limey, Pommy B*****d, Redcoat, Rosbeef....

Edited October 25, 2009 by Nicholas
inappropriate obscenity

[Bill]