Late Pennsylvanian find, Coelacanth or Dipnoan bones?

[Petalodus12]

Hi all,

I’m not sure if I’ve posted this find before, but I figured I would anyway because I believe it warrants it’s own thread. I found this find a few years back at one of the localities I most consistently collect at, which is a shaly exposure of the Connelsville Sandstone in western PA. It usually preserves plants quite well, and was described by W.C. Darrah back in the 60s. It has also produced some very early examples of Walchia, an early conifer.

However, it is not well known for vertebrate fossils, as sandstones don’t seem to be the preferred type of rock where vertebrates are found in the area. If you’ve seen my other posts you’ve probably realized that most of the time vertebrate fossils are restricted to shales and limestones, often closely related to coals. And in the shales especially, concentrations of material are usually lag deposits and do not represent associated remains. Here I have something different.

 

Its a small jumble of bones, with no diagnostic features whatsoever. However I can rule out actinopterygian material because it lacks the thick shiny scales so characteristic of this group. I’m almost certain it’s not tetrapod material as (1) they are incredibly rare and (2) the ribs seem to be too thin. I’m also fairly confident that it represents a single individual as the bones are locally concentrated and I’ve never seen them before from this locality.

I’ve found bones like these before in other more characteristic deposits, although they are never articulated. I’m relatively sure that they come from some sort of sarcopterygian, possibly a dipnoan or coelacanth. I would be very happy if anyone could shed some light on the general grouping of this fossil. If not, then just appreciate it as a random jumble of bones from a not very often seen locality.

 

As always, stratigraphy:

Connelsville sandstone

Casselman Formation

Conemaugh Group

 

And age:

Late Pennsylvanian (Stephanian/Missourian ~302 MYA)

 

 

 

[Petalodus12]

[Fossildude19]

Any chance of sharper images? When blown up, these get quite fuzzy.

The bones I see do look similar to Rhabdoderma sp or Diplurus newarki coelacanth bones. 

 

[Petalodus12]

1 hour ago, Fossildude19 said:

Any chance of sharper images? When blown up, these get quite fuzzy.

The bones I see do look similar to Rhabdoderma sp or Diplurus newarki coelacanth bones. 

 

Yes I’ll post some better photos

[Petalodus12]

[Petalodus12]

1 hour ago, Fossildude19 said:

Any chance of sharper images? When blown up, these get quite fuzzy.

The bones I see do look similar to Rhabdoderma sp or Diplurus newarki coelacanth bones. 

 

Hopefully the above photo is a bit clearer. I sincerely appreciate your input, as it tells me that I am somewhat on the right track. I assume that they can only be assigned to a large group do to the lack of diagnostic material, though.

[Fossildude19]

34 minutes ago, Petalodus12 said:

Hopefully the above photo is a bit clearer. I sincerely appreciate your input, as it tells me that I am somewhat on the right track. I assume that they can only be assigned to a large group do to the lack of diagnostic material, though.

Well, it is a bit better, but the bones do lack any kind of diagnostic detail for me to make out. 

Neat, just the same.  

[Petalodus12]

10 minutes ago, Fossildude19 said:

Well, it is a bit better, but the bones do lack any kind of diagnostic detail for me to make out. 

Neat, just the same.  

Thanks, I appreciate it! I think I'm going to head back to this site soon to see if I can find more specimens like this, or to see if it was just an anomaly.

[Fossildude19]

44 minutes ago, Petalodus12 said:

Thanks, I appreciate it! I think I'm going to head back to this site soon to see if I can find more specimens like this, or to see if it was just an anomaly.

I think you may have found a really productive area. 

Fingers crossed for you going back there!    

 

[Titan]

That's really exciting, I hope you find more like it!!!

[Petalodus12]

5 hours ago, Titan said:

That's really exciting, I hope you find more like it!!!

Thanks, hopefully I do! I have a suspicion that it was an anomaly at this site, though

[jdp]

Hard to tell. I think I'd prefer a coelacanth ID to a lungfish ID, but there's nothing concrete I'd point to in order to back that up.

[Petalodus12]

6 hours ago, jdp said:

Hard to tell. I think I'd prefer a coelacanth ID to a lungfish ID, but there's nothing concrete I'd point to in order to back that up.

Thanks! I think I’m leaning towards Coelacanth, too.