Middle eocene Sawfish rostrum? Found in Dammam formation, midra shale member, Qatar.

[deltav2]

Picture on the left is the cross section of the broader side 

The entire thing is 1.7 cm in length

Age: Middle eocene
Geological formation: Dammam, midra shale member 

 

Edited February 2 by deltav2

[Fossildude19]

Looks more like a stingray barb, to me. 

[sixgill pete]

Yes, stingray barb section as @Fossildude19 suggested.

 

This is a middle Eocene sawfish rostral tooth (Pristis)

 

  

 

 

 

 

[deltav2]

23 minutes ago, Fossildude19 said:

Looks more like a stingray barb, to me. 

That's what I thought too but the texture, colour, and shape is different from the ones I usually find, and this one does not have any barbs
Here's one I found a while back

Or could it be a different species of ray? 

 

13 minutes ago, sixgill pete said:

Yes, stingray barb section as @Fossildude19 suggested.

 

This is a middle Eocene sawfish rostral tooth (Pristis)

 

  

 

 

 

 

Yes, but I meant the rostrum part not the rostral denticle itself 

[Fossildude19]

The tiny size would argue against it being a rostrum.

 

I think the spines are either poorly developed, or worn down.

[Fossildude19]

Interesting alternative found HERE.

Sea Urchin Spines.

 

[deltav2]

14 minutes ago, Fossildude19 said:

The tiny size would argue against it being a rostrum.

 

I think the spines are either poorly developed, or worn down.

I agree, it's probably not a rostrum(any chance it could be a juvenile one?), but it seems very unlikely that it is a stingray barb, the cross section is completely different

12 minutes ago, Fossildude19 said:

Interesting alternative found HERE.

Sea Urchin Spines.

 

Sea urchin spines are symmetric but mine has a ridge running along one side of it, and it is also UV reactive like my other fish remains I find, while the sea urchin spines arent

 

 

 

 

Edited February 2 by deltav2

[Fossildude19]

Well, it looks like fish bone, to me. 

So, either a stingray barb, or some sort of fish spine. 

Stingray barb makes the most sense to me, but, obviously you disagree.

[sixgill pete]

No doubt ot is stingray barb to me. A small broken piece of one that is. And worn down as Tim suggested.

[deltav2]

8 minutes ago, sixgill pete said:

No doubt ot is stingray barb to me. A small broken piece of one that is. And worn down as Tim suggested.

I think it's unlikely because of how even the wear is on all the barbs, and they(the barbs) seem to be much more spaced out than on a regular stingray barb. And since stingrays only use it for self defense rather than something like feeding, it would have taken a really long time for it to accumulate this level of wear, without it being shed. If it is a stingray spine, then it has to be some rarer species because I am not able to find a good reference to compare it with online

Edited February 2 by deltav2

[sixgill pete]

4 minutes ago, deltav2 said:

I think it's unlikely because of how even the wear is on all the barbs, and they(the barbs) seem to be much more spaced out than on a regular stingray barb. And since stingrays only use it for self defense rather than something like feeding, it would have taken a really long time for it to accumulate this level of wear, without it being shed. If it is a stingray spine, then it has to be some rarer species because I am not able to find a good reference to compare it with online

 

The first thing I will say is I have been wrong before and I will be wrong again. I will look at some of my references as soon as I have a chance.

 

[Tidgy's Dad]

+1 for worn, partial stingray barb.

[Northern Sharks]

My initial reaction was also ray barb, but catfish also can have serrated barbs in their pectoral fins. Just a thought.

[Mikrogeophagus]

I have some partial Arius catfish spines from the TX Eocene and I can say they look pretty different from this. The barbs on them tend to be more prominent in size/hook shape on one side while the opposing barbs are more so bumps. The striations along the flat surfaces of the catfish spines tend to branch/anastomose and are more defined. Not saying this for sure isn't catfish, but just want to state it is unlike the ones I have seen.

 

My vote is stingray as well

 

Edit: I would also like to bring up the symmetry of the spines. Someone should fact check this, but I am under the impression stingray barbs would roughly have a bilateral symmetry. The barbs on either side of the spine should look about the same as their counterpart (perhaps because the spine lays flat on the living animal?). In the case of catifish spines, there is a clear top and bottom. The barbs on either side are asymmetric and located on either the concave or convex side of the spine as the structure, in life, would be set with one edge facing the front of the animal and the other facing the back. 

Edited February 3 by Mikrogeophagus

[deltav2]

Adding on some more images to help ID it, and also comparing it with images of stingray barbs to highlight the differences between them

Bottom ones are stingray barbs

The surface of a stingray barb(image on the right) is much more glossier, and also has many ridges running along it compared to my other piece, which is mostly flat (but curved, as shown in the cross section)

I think it is too unlikely for a stingray barb to get worn down like this, but if anyone has any examples please share

Last image showing it from the side, the tips of the bumps are more lustrous than the rest of the piece 

 

 

 

 

Edited February 4 by deltav2