5/13/19 Oglesby, IL Roadcut- Pennsylvanian shark bits, brachiopods and more

[Archie]

Here's another Petalodont tooth in lingual view to compare that last tooth with, I've circled the basal ridge on both. I'll get a pic of a tooth called Pristodus which is very similar to your multi-cusped tooth.

[deutscheben]

Thank you @Archie! I was really going back and forth on that one. So it would appear the tooth got sort of backed into the brachiopod root-first then.  

[Archie]

Glad to be of help! Yes, I think your right, it looks like the root may have  punctured down through the brachiopod shell under pressure. Its a lovely association piece!

 

[Elasmohunter]

On 5/29/2019 at 7:31 PM, deutscheben said:

@Fossildude19 helpfully suggested in an ID thread that my last piece may be a fish premaxilla, which got me thinking about another one of my finds, the bit associated with the brachiopod shell in my 5th post above. Looking at it in a new light, I am now thinking it is actually a scale, not a tooth. I tried to take a closer pic, but my phone is limited in resolution unfortunately. Here are couple shots in different light:

 

 

This certainly looks like a Petalodont tooth to me, so it's likely a member of order Petalodontiformes, but I'm hesitant to assign it to one of the four petalodont families without being able to see more (Janassidae, Pristodontidae, Petalodontidae, or Belantseidae).

[Elasmohunter]

On 5/26/2019 at 3:46 PM, deutscheben said:

This little piece of something was on the same rock as the spine above- it's much too small for me to be able to make out any identifying features, unfortunately. 

 

 

Finally, I have mostly prepped this piece out- I stopped because small bits were coming off. I would have to consolidate it before going any further and all I have for that is cyanoacrylate. I'm honestly not really sure what it is- it does not have the enamel shine of shark teeth, with most of it looking more like a tooth root. That plus the multiple small cusps/teeth on top make me think it's actually part of a fish jaw, perhaps? I would love to hear the opinions of some folks who have more experience with Carboniferous fish. @Archie @fossilized6s @TNCollector @RCFossils @Elasmohunter

 

Concerning your multicuspid tooth, I think @Archie is correct to put it within family Pristodontidae. Because it's multicuspid, it's probably an upper tooth. I'm hesitant to classify it further, but I will mention that Pristodus, Petalorhynchus, Siksika, and Davodus have only been reported from the Mississippian, but Megactenopetalus, Calopodus, and Peripristis have been reported from the Pennsylvanian.

From what I've observed in my work in the Mississippian, bony fish teeth usually resemble cylinders and don't come articulated in the jaw.

Hope that helps!

[deutscheben]

Thanks @Elasmohunter , that last one still has me perplexed. I will do some research on the family you mentioned. 

[Elasmohunter]

1 hour ago, deutscheben said:

Thanks @Elasmohunter , that last one still has me perplexed. I will do some research on the family you mentioned. 

Good luck! Let me know if I can be of any further assistance. Once my schedule frees up, I can try to give you a more definite identification. If you have access to it, the Handbook of Paleoichthyology (Paleozoic Elasmobranchii) would prove a useful source.

[MeargleSchmeargl]

On 5/20/2019 at 2:30 PM, deutscheben said:

 

Would you have been able to take it out with a few inches of matrix around it to keep it intact, or was the rock that hard/unpredictable? 

[deutscheben]

Unfortunately no, the rock was too thick to cut and quite hard as well, and I only have manual tools. But now I will definitely keep an eye for brachiopods with similar preservation in the future.

[deutscheben]

I have been slowly going through the blocks I brought home and doing some prep when I have time. As is often the case with this site, as I look at the pieces I find fossils I didn't even notice in the field- they are just so full of ancent life!

 

First is another shark tooth that I was able to expose more of. Unfortunately it is very beat-up- it appears to be a petalodont tooth of some sort- perhaps Peripristis with only (part of) one cusp remaining? 

 

The next piece appears to be bone of some sort, presumably fish? It has a very distinctive shape with a small dark knob on the back side. I may try to prep more around it, but the flat portion is very thin, so I don't want to risk destroying it. 

 

 

 

 

[deutscheben]

The other two finds are bivalves- I really don't have any guess as to ID on these. The first is just a partial impression-I tried prepping it but none of the original shell is left. It's next to a Linoproductus brachiopod.

 

 

The second one is smaller and more well preserved- a lovely little half-shell. I would appreciate any ID suggestions from folks more familiar with Pennsylvanian bivalves.