Various woodbine shark/fish teeth?

[Shaun-DFW Fossils]

Here are the teeth I’ve extracted so far from small slabs I found in southern Johnson County near Grandview, Texas last week in the woodbine group. Any ideas on identification for these? Sorry that my photos may be somewhat lacking. I don’t yet have the scientific species memorized, so I welcome scientific names but also common names so I can better picture what it looked like. I have more to remove from matrix when I have time. I used the dremel 290 and I didn’t break any teeth, though you see at least one or two were already broken when I found them. Thank you!

[Fossildude19]

Croppped and contrasted:

 

 

[Shaun-DFW Fossils]

59 minutes ago, Fossildude19 said:

Croppped and contrasted:

 

 

Thanks for taking the time to help me out, that made a difference! I should also add that the bottom row might not even be any sort of fossils, I was thinking maybe some sort of fish teeth in one or two cases?

[Mikrogeophagus]

I think you mentioned before that this is close-ish to the Woodbine/Eagle Ford boundary. There are all sorts of weird hard layers that can pop up in the Woodbine, but keep in mind this could instead be from the basal Eagle Ford in something called the Tarrant Formation. I've hunted the Tarrant a little and it shares some visual resemblance. Also, the shark fauna leans more Eagle Ford in my opinion. Any time I'm finding sharks in the Woodbine, Cretodus semiplicatus (big scary tooth with enamel wrinkling and cusplets) is a major fraction of the finds while Squalicorax (serrated triangles you have lots of), commonly known as crow sharks, are often present, but not this dominant. I am leaning towards your site being Tarrant Fm, but of course I could easily be wrong. 

 

Anyways, all those serrated teeth you have are from the genus Squalicorax. Their precise species has been a topic for debate. Squalicorax falcatus is what you will see most often, but this is more of a bucket term that in reality does not represent the true diversity present in the record. There are other names you might see such as Squalicorax volgensis and Squalicorax curvatus that have also had taxonomic problems and are becoming less favored these days. Many people opt to just call these Squalicorax sp. which is a broad term that does not run the risk of being incorrect. It would be most wise for you to stick with Squalicorax sp. and be done, but some people, like me, feel a little empty when labeling finds in this manner.

 

Luckily it is your collection and you have no one to answer for. Call it a unicorn tooth if you want! Anyways, I have found a species from around the same time period in Europe that was recently described as Squalicorax bernardezi. I think it compares pretty well with my teeth from the late Cenomanian-middle Turonian here in TX. I've started labeling my specimens with that name. Just be warned that it might not be precisely correct as you are dabbling into the forefront of shark tooth taxonomy here.

 

Common in some deposits are Squalicorax baharijensis which have some distinct differences from the teeth you are showing (big mesial hump).

 

Unfortunately, I can't make much out of the smooth-edged teeth as there is little to go on for identification.

[Shaun-DFW Fossils]

1 hour ago, Mikrogeophagus said:

I think you mentioned before that this is close-ish to the Woodbine/Eagle Ford boundary. There are all sorts of weird hard layers that can pop up in the Woodbine, but keep in mind this could instead be from the basal Eagle Ford in something called the Tarrant Formation. I've hunted the Tarrant a little and it shares some visual resemblance. Also, the shark fauna leans more Eagle Ford in my opinion. Any time I'm finding sharks in the Woodbine, Cretodus semiplicatus (big scary tooth with enamel wrinkling and cusplets) is a major fraction of the finds while Squalicorax (serrated triangles you have lots of), commonly known as crow sharks, are often present, but not this dominant. I am leaning towards your site being Tarrant Fm, but of course I could easily be wrong. 

 

Anyways, all those serrated teeth you have are from the genus Squalicorax. Their precise species has been a topic for debate. Squalicorax falcatus is what you will see most often, but this is more of a bucket term that in reality does not represent the true diversity present in the record. There are other names you might see such as Squalicorax volgensis and Squalicorax curvatus that have also had taxonomic problems and are becoming less favored these days. Many people opt to just call these Squalicorax sp. which is a broad term that does not run the risk of being incorrect. It would be most wise for you to stick with Squalicorax sp. and be done, but some people, like me, feel a little empty when labeling finds in this manner.

 

Luckily it is your collection and you have no one to answer for. Call it a unicorn tooth if you want! Anyways, I have found a species from around the same time period in Europe that was recently described as Squalicorax bernardezi. I think it compares pretty well with my teeth from the late Cenomanian-middle Turonian here in TX. I've started labeling my specimens with that name. Just be warned that it might not be precisely correct as you are dabbling into the forefront of shark tooth taxonomy here.

 

Common in some deposits are Squalicorax baharijensis which have some distinct differences from the teeth you are showing (big mesial hump).

 

Unfortunately, I can't make much out of the smooth-edged teeth as there is little to go on for identification.

Thanks for the thoughtful and thorough response, that helps in giving me some direction! I am well aware of the Tarrant formation since my first love is actually ammonites, especially conlinoceras tarrantense, so that’s what I was looking for. But the Mancos app (sometimes wrong) shows this creek to be a little more on the woodbine side, and I found no ammonites, only oysters. I also found the typical iron rich deposits and large, round rocks associated with the woodbine. But I know it’s not a perfect conformity so it very well could be a little peek inside the Eagle Ford at this one spot. Thanks again!