Oglesby 10/08/22

[Tales From the Shale]

This Saturday I went over to Oglesby again joined this time by fellow user @Joseph Fossil. We hunted for about six hours straight, the trip being the most productive I've had here. I showed him and his friend what to look for when searching for Chondricthyan teeth. Joe collected 2 Cladodont teeth, and we both walked out with two partial Petalodus specimens. 

 

Here's a very complete Echinaria.

Neospirifir dunbari, they'll look nice when prepped and put back together.

An Antiquatonia portlockianus

Linoproductus cora

A pair of Parajuresania nebrascensis

Composita argentia: A few of these I found had their brachidiums intact.

Chonetina flemingi: Found this by mistake while washing material at home.

Petalodus ohioensis: Long have I searched for this fish, and here it is.

Wilkingia terminalis: easily my favorite find from this location. It's like an ancient razor clam analogue.

Always a pleasure to hunt with fellow forum members. Having the company can make the long drives not feel as so. He and I have made arrangements to hunt more of his homestate in the future.

Edit:

Images added for clarity on the *tooth* pictured below. Found in some rubble, within the shale layer of the locality.

 

Some form of texture is visible from the top of the piece.

Top down:

From the side:

Upside down + a brachiopod for comparison:

It appears to be flat, with some depth in its shape taking the form of ridges on the face. There are what appear to be some form of serrations on the *top* end of the structure as pointed out above.

Edited October 11, 2022 by Tales From the Shale

[Tidgy's Dad]

Some very nice finds.

[connorp]

How was the poison ivy? The site was covered when I last visited a couple months ago.

[Praefectus]

Nice finds! 

[Joseph Fossil]

@Tales From the Shale That Petalodus specimen is nothing less than impressive!!!

[Tales From the Shale]

1 hour ago, connorp said:

How was the poison ivy? The site was covered when I last visited a couple months ago.

I brought a machete with me throughout the summer to manage the noxious plants in hopes of allowing others easier access. It's about 50 percent open now, but give it another month and it should be wide open.

[deutscheben]

Thanks for the post, that’s a nice variety of brachiopods. 
 

The Petalodus you posted doesn’t quite look right for a shark tooth. It’s hard judging from a picture so I could be wrong but the texture and shape seem off. 
 

I’d love to see more pictures, and the other teeth y’all found, though!

[Tales From the Shale]

25 minutes ago, deutscheben said:

Thanks for the post, that’s a nice variety of brachiopods. 
 

The Petalodus you posted doesn’t quite look right for a shark tooth. It’s hard judging from a picture so I could be wrong but the texture and shape seem off. 
 

I’d love to see more pictures, and the other teeth y’all found, though!

As in it isn't a shark tooth or a tooth in general? If not what could it be? I saw what appeared to be serrations on the top edge of the structure. I was thinking that it was a larger fragment of the crown, with no root.

[connorp]

1 minute ago, Tales From the Shale said:

As in it isn't a shark tooth or a tooth in general? If not what could it be? I saw what appeared to be serrations on the top edge of the structure. I was thinking that it was a larger fragment of the crown, with no root.

Can you post pictures from other angles? And was this found in the limestone or the grey shale?

[ClearLake]

I really enjoy the brachiopods that you and others have posted from there. It’s on my list of places to visit during one of our trips through the area. Although I’ll have to overcome my wife’s memory of our unpleasant chiggar encounter at our last Illinois roadcut outing - haha!!  Thanks for posting your finds. 

[Tidgy's Dad]

Could it be a fragment of brachiopod shell showing part of the hinge line and interarea? 

[Tales From the Shale]

1 hour ago, connorp said:

Can you post pictures from other angles? And was this found in the limestone or the grey shale?

 

49 minutes ago, Tidgy's Dad said:

Could it be a fragment of brachiopod shell showing part of the hinge line and interarea? 

It was found in gray shale matrix, however I found it in a rubble pile. It has texture across the face, as well as the top of the structure. The top almost appears to have some form of serrations. Its got some minor fracturing, in the structure with pyrite and crinoid pieces distributed throughout the matrix.

[deutscheben]

My best guess would be internal brachiopod fragment, yeah. I don’t have any similar ones for reference on hand unfortunately. 
 

I do have a couple of partial Petalodus for comparison though. Recognizing them is something that takes some time and experience to develop because it really is about textures and structure and the way different fauna tend to fossilize. 
 

 

Chondrichthyan teeth when fossilized here are preserved with the different layers of the tooth- the external enamel and then the internal structure.

 

 

 

 

That means when they are damaged you should see the contrast between the layers. Petalodus in particular has an extremely thin outer enamel layer that tends to crack. 

 

 

 

The piece you shared looks to have a consistent texture throughout, and though partially crushed still seems robust. This is more typical of the preservation for brachiopods or echinoderm material. 
 

The color is also more typical of invertebrate material, again as a result of the way they fossilize- the types of minerals they are made of.

 

Finally, the texture is another indicator- teeth tend to be very smooth on the crown and in many cases even shiny or slick(as a result of the enamel). The fossil you have posted has a slightly bumpy and wrinkled texture.

 

I hope you find this helpful- maybe we can hit the site up together some time and I can show you in person. 

[Tales From the Shale]

4 hours ago, deutscheben said:

My best guess would be internal brachiopod fragment, yeah. I don’t have any similar ones for reference on hand unfortunately. 
 

I do have a couple of partial Petalodus for comparison though. Recognizing them is something that takes some time and experience to develop because it really is about textures and structure and the way different fauna tend to fossilize. 
 

 

Chondrichthyan teeth when fossilized here are preserved with the different layers of the tooth- the external enamel and then the internal structure.

 

 

 

 

That means when they are damaged you should see the contrast between the layers. Petalodus in particular has an extremely thin outer enamel layer that tends to crack. 

 

 

 

The piece you shared looks to have a consistent texture throughout, and though partially crushed still seems robust. This is more typical of the preservation for brachiopods or echinoderm material. 
 

The color is also more typical of invertebrate material, again as a result of the way they fossilize- the types of minerals they are made of.

 

Finally, the texture is another indicator- teeth tend to be very smooth on the crown and in many cases even shiny or slick(as a result of the enamel). The fossil you have posted has a slightly bumpy and wrinkled texture.

 

I hope you find this helpful- maybe we can hit the site up together some time and I can show you in person. 

Yeah looking at it now, the coloration is exact to that of the crinoid stems that accompany it in the matrix. Just the blade like fracture on top looked like a cutting surface, which is what threw me off. If you'd like to go out there to hunt, I would love to join up as I'm always willing to learn. I just acquired new more sophisticated tools I want to try out.