Cepholopod? Fossil ID

[abyssunder]

There are some things:
It was supposed that the OP specimen was found in Paleozoic / Carboniferous / Pennsylvanian sediments.
Sciponoceras gracile or any other of this genus are from Cretaceous like all Baculitids.
The specimen in question has a round shape in cross section and it does taper.

 

Something don't match.

[KimTexan]

8 hours ago, abyssunder said:

There are some things:
It was supposed that the OP specimen was found in Paleozoic / Carboniferous / Pennsylvanian sediments.
Sciponoceras gracile or any other of this genus are from Cretaceous like all Baculitids.
The specimen in question has a round shape in cross section and it does taper.

 

Something don't match.

 

I never thought it was Cretaceous. Someone else suggested that and the Sciponoceras.

Others wanted to see more fossils from the site to confirm the period. I finally found some tiny fossils that I believe were Fenestella and narrowed it down to Pennsylvanian. It certainly isn’t Quaternary so it has to be Pennsylvanian, 

Do you think it could be the Pseudoorthoceras? I’ve thought it must be a type of orthoceras from the start, but I have never found one before.

[doushantuo]

sorry for the low quality scans..

Flower's Pseudorthoceras concept might be based on obsolete concepts of the taxonomic use of cameral deposits,BTW.

Posted the link to this one a while back

 

 

[DPS Ammonite]

Kim, the area that you collected this fossil looks like relatively new river deposits. Did you collect this from a rock outcrop that was not recent (probably unconsolidated) river deposits? Did you collect this as float and from the river deposits? If you did collect this from a solid outcrop, were the crinoid and bryozoan also from that solid outcrop or were they also float? Were there other fossils in the solid outcrop that you noticed but did not collect? 

[abyssunder]

14 hours ago, KimTexan said:

Do you think it could be the Pseudoorthoceras? I’ve thought it must be a type of orthoceras from the start, but I have never found one before.

If it's an orthoconic nautiloid it should have chambers and a siphuncle, which in a median longitudinal section can be visible. In a transverse section only the siphuncle is visible.
It could be also the remnant of a siphuncle, as it was suggested by Don.
The third possibility, as I suggested, might be a trace fossil, a burrow.
Without a longitudinal section everything is just a guess.

[BobWill]

Burrow is certainly a possibility but then what appears to be segmentation would need to accounted for. For whatever reason sometimes a siphuncle does not preserve, not just because it's absent like in a body chamber,  just not there. With only the shape and possible constrictions and possible septa we should consider that it may be either Euloxoceras, Mooreoceras or Dolorthoceras besides Pseudorthoceras or maybe not even nautiloid. It could be a Bactrites. I've never heard of a cephalopod from this area big enough for it to be the siphuncle but then I don't get out much

[doushantuo]

[Uncle Siphuncle]

11 hours ago, BobWill said:

Burrow is certainly a possibility but then what appears to be segmentation would need to accounted for. For whatever reason sometimes a siphuncle does not preserve, not just because it's absent like in a body chamber,  just not there. With only the shape and possible constrictions and possible septa we should consider that it may be either Euloxoceras, Mooreoceras or Dolorthoceras besides Pseudorthoceras or maybe not even nautiloid. It could be a Bactrites. I've never heard of a cephalopod from this area big enough for it to be the siphuncle but then I don't get out much

Not necessarily what’s going on here, but I have found Cretaceous burrows that were incrementally back filled, imparting semblance of segmentation.  Slightly tapered too.  I’d surmise that the same process could have occurred 150 million years esrlier as well.  Donated due to scientific interest and my lack of display space.

[BobWill]

1 hour ago, Uncle Siphuncle said:

Not necessarily what’s going on here, but I have found Cretaceous burrows that were incrementally back filled, imparting semblance of segmentation.  Slightly tapered too.  I’d surmise that the same process could have occurred 150 million years esrlier as well.  Donated due to scientific interest and my lack of display space.

That reminds me of some enigmatic burrows from Jacksboro that have what appears to be segmentation but it's too irregular for septa so not well understood. Did you keep pictures or remember if the divisions had an evenly spaced and angled pattern like Kim's?

[Uncle Siphuncle]

1 hour ago, BobWill said:

That reminds me of some enigmatic burrows from Jacksboro that have what appears to be segmentation but it's too irregular for septa so not well understood. Did you keep pictures or remember if the divisions had an evenly spaced and angled pattern like Kim's?

Pics at home.  Will post.

[Uncle Siphuncle]

12 hours ago, BobWill said:

That reminds me of some enigmatic burrows from Jacksboro that have what appears to be segmentation but it's too irregular for septa so not well understood. Did you keep pictures or remember if the divisions had an evenly spaced and angled pattern like Kim's?

Burrow

[KimTexan]

Oops! I thought the dialogue had died out on this. I’ll have to get back to this tomorrow.

@DPS Ammonite the fossils were all from the same 20-30 foot area. There were no other fossils that I saw other than what I shared. I believe it was an independent outcrop of limestone.

[KimTexan]

This is a pic of the area.

It did not appear to have river material mixed in or deposited there. It was above the river maybe 30-40 feet and a distance away from the river. The rock is brownish gray for the most part. The fossils embeddd in the rocks are cream to tan colored. 

The river itself has mostly tan sand with some orange mixed in. I found the specimen almost at the top of the hill. So I believe it was from the rocks not the river.

[JohnJ]

It's possible that photos from additional angles could continue to narrow the possibilities on your find. 

[KimTexan]

I can take more pics this evening.

 

This is it in situ.

I suppose it could have been deposited in one of those 100 year flood kind of situations or even dumped there a hundred years ago for construction. There was a bridge nearby. The rock could have been brought in to help prevent erosion of the bridge foundation when it was built a long time ago. I have no idea how long the bridge has been there, but the trees upon and around the hill look pretty old.