Pennsylvanian Poterioceras Protoconch Please?

[BobWill]

I am looking for information about the protoconch (or even the near-apex shell) of the nautiloid Poterioceras sp. from the Pennsylvanian Period. I find a lot of broken pieces at the Jacksboro site in Texas but they are always missing the early parts. The only mention I've found so far is from the author of a paper who had never seen any either.

Edited June 13, 2015 by BobWill

[Bullsnake]

Hi, Bob.

A search on JSTOR yielded some results.

[BobWill]

Thanks Steve. I've been meaning to register, now's the time. What search criteria did you use?

[BobWill]

Oh, it's restricted to affiliates of institutions.

[Bullsnake]

Oh, it's restricted to affiliates of institutions.

Not necessarily.

You can register and type in key words (I used the taxonomic names in your post on the home page), and add 3 items to your bookshelf for reading. I do think you are right that there is limited access on some, but you can access some good info.

It's kind of like any site, you click around to see what you can find/access.

You can get deeper into them at a cost, I think, but I haven't pulled the trigger on that yet.

Give it a try , and sorry if it's not quite what you're looking for.

P.S. I'd like to see some of your specimens.

Edited June 14, 2015 by Bullsnake

[BobWill]

Thanks, I'll get some pictures in daylight tomorrow but I found a small, very evolute, planispiral nautiloid I have been unable to ID. I finally realized the characters I'd seen somewhere before were the oddly angular shape at the ventral margins and the sinuous growth lines of Poterioceras. It got me wondering if the slightly curving, but generally orthoconic shell could have grown exponentially less-curved from a coiled beginning. If someone already found a very different protoconch I can just go back to finding an ID for the new fossil.

[DPS Ammonite]

Bob,

Check your local university library for access to JSTOR and other helpful databases. Also, check out your local library's website.You may be able remotely access, online, JSTOR if you have a library card.

[BobWill]

Thanks John. I'll try soon.

[abyssunder]

Bob,

All I found about Poterioceras is as follows:

Descriptions of Some New Species of Devonian Fossils - Clinton R. Stauffer http://www.jstor.org/stable/pdf/30078196.pdf

Lower Mississippian Cephalopods of Michigan,Part I.Orthoconic Nautiloids - A.K.Miller,H.F.Garner http://deepblue.lib.umich.edu/bitstream/handle/2027.42/48270/ID109.pdf?sequence=2&isAllowed=y

Poterioceras, I 183
fusiforme, I 183
northviezuense, I 163,I 184
robustum, I162, I 163, I 183-84,III 117
SP., I 162, I 184-85, III 117

Maybe could help.

P.S.-All the three volumes of the second document are in my library.The summary is at the end of Volume III.

Edited June 14, 2015 by abyssunder

[piranha]

The attached figures of Poterioceras are from these Journal of Paleontology papers.

Please send me a PM with your email address and I'll be happy to send them for you.

 

Miller, A.K., & Youngquist, W. (1947)

The discovery and significance of a cephalopod fauna in the Mississippian Caballero Formation of New Mexico.

Journal of Paleontology, 21(2):113-117

 

Miller, A.K., & Youngquist, W. (1948)

The cephalopod fauna of the Mississippian Barnett Formation of central Texas.

Journal of Paleontology, 22(6):649-671

 

Youngquist, W. (1949)

The cephalopod fauna of the White Pine shale of Nevada.

Journal of Paleontology, 23(3):276-305

 

Gutschick, R.C., & Treckman, J.F. (1957)

Lower Mississippian cephalopods from the Rockford Limestone of northern Indiana.

Journal of Paleontology, 31(6):1148-1153

 

 

 

 

[piranha]

After looking at northtexasfossils.com I discovered a fragment of Poterioceras curtum from the Finis Shale.

Here are some additional figures of Poterioceras sp. aff. P. curtum from the Pennsylvanian of eastern Ohio.

 

 

Sturgeon, M.T. (1946)

Allegheny Fossil Invertebrates from Eastern Ohio: Nautiloidea.

Journal of Paleontology, 20(1):8-37

 

 

 

[BobWill]

Thanks abyssunder and piranha. I saw Lance's great example and a few from other DPS members but none have the protoconch and the same with what I see in these papers. It may be tomorrow now before I get some pictures but this looks very promising for a possible mystery solved if I'm right about this.

[BobWill]

Here are most of the Poterioceras pieces I have from Jacksboro.

Here is the fossil with some very similar features. Angular bend along ventral margin with slight depression on ventral side of each corner and the distinctive growth lines. Sorry about the photo. I'll get some help with it and post better.

edit: correction, the slight depressions at the "corners" are on the lateral side of the margin not the ventral side becoming very prominent on the larger body chamber in the first picture.

Edited June 16, 2015 by BobWill

[cngodles]

Time to resurrect this one, because I have some specimens and some additional questions.

 

I've been calling these Ctenobactrites isogramma, but now I'm considering Poterioceras.

 

Age is Kasimovian, Late Pennsylvanian. Conemaugh Group, Glenshaw Formation, Pine Creek limestone.

 

I wrote about Ctenobactrites isogramma here, but now I'm having doubts. I'm hoping that perhaps you've learned more in the 7 years since the previous post.

 

Specimens

 

Specimen still in the stone. Normal sized rock hammer for scale.

 

CG-0369 - Isolated Pieces. There are at least two difference specimens here.

 

 

CG-0436 - This is an intact specimen still attached to the steinkern. It gets very wide at the bottom, it looks like an animal hoof.

Scale bar = 1 cm.

 

 

[cngodles]

I’m more than convinced that I have Poterioceras after reading through some of the literature. 

[Tidgy's Dad]

Interesting thread. 

I love it when these old ones are resurrected. 

And Adam always adores alliteration. 

[erose]

There is a way to get a lot of JSTOR content for free.  Or at least you can read stuff online. See this link: https://about.jstor.org/get-jstor/

 

I have found this very helpful when I am not 100% sure a particular paper is going to help me.  On occasion I find a really valuable one for identification and then I go the extra steps to hunt down a hard copy.

 

But at least this allows you to read up to 100 papers a month for free.

[BobWill]

On 5/31/2022 at 9:15 PM, cngodles said:

I'm hoping that perhaps you've learned more in the 7 years since the previous post.

 

 

 

 

 

 

 

Ah, has it been 7 years? I'm feeling like a real slacker now. I sort of let this one slide so I have nothing new to offer. Those sure do look similar though.

 

Thanks for the tip @erose. I need to get back on that horse and try again...

[cngodles]

Adding a new specimen, I finally photographed it. I'm not sure there is even a unique protoconch with these. They appear to come down to a blunt point.

 

Poterioceras curtum

CG-0700

Scale bar = 1 cm.

Pine Creek limestone; Glenshaw Formation

Armstrong County, PA

 

Wikipedia has these ending in the Mississippian, but I'm finding this in the Late Pennsylvanian. I have not found any reports in younger rocks to date; this may be where they disappear from the fossil record.

 

Edited January 1 by cngodles

[BobWill]

On 1/1/2024 at 12:36 PM, cngodles said:

Adding a new specimen, I finally photographed it. I'm not sure there is even a unique protoconch with these. They appear to come down to a blunt point.

 

 

The sutures are certainly closely spaced at what would be the initial camera on yours but in the  intervening 8 1/2 years I got a copy of the "Treatise K (3)" which shows them to taper down to a small diameter and, to answer my original question, they are indeed slightly curved at the protoconch, so should be considered cyrtocone. However, that does rule out the specimen from this post with a much longer curve that I thought might be one so I need to find it and have another look. Thanks for posting this.

[cngodles]

I’ll post a passage I wrote up late last year. The Treatise is where they got the detail wrong, because they combined it and Brachycycloceras.

 

Poterioceras curtum (Meek & Worthen, 1860)

This breviconic cephalopod species first rose as Cyrtoceras curtum (Meek, 1860). Later, authors declared it to be the adult stage of Brachycycloceras (Furnish et al., 1962), as published in the Treatise of Invertebrate Paleontology (1964, Part K Mollusca 3, Furnish and Glenister). Researchers at the time considered today’s Brachycycloceras to be the deciduous portion of a larger conch, a cephalopod formerly and currently known as Poterioceras. Much later, new evidence and research redivided the names (Windle, 1973), prompting Niko and Mapes (2009, 2010) to redescribe species of Brachycycloceras.

 

########
 

Also, the whole Treatise is free online now: https://journals.ku.edu/InvertebratePaleo/article/view/5259/4737

Edited January 8 by cngodles

[BobWill]

13 hours ago, cngodles said:

I’ll post a passage I wrote up late last year. The Treatise is where they got the detail wrong, because they combined it and Brachycycloceras.

 

 

Thanks but now I'm even more confused. A pencil note in my 1964 paper copy has Brachycloceras reassigned to Poterioeras (Sturgeon et al. 1997) but still separated in the text. I can certainly mark through that and make a new note though, or just start using the online version

 

Frankly, I never saw much similarity between the two but the Brachycycloceras species I find here seem to expand less rapidly than the Poterioceras, at least for the portions of the conchs I have found. However you parse the "breviconic" feature it could still apply to both and we should  also consider both to be cyrtoconic.

[cngodles]

The idea was that Brachycycloceras was the deciduous part of Poterioeras—that the small part fell off the big part as the creature matured.

 Windle did the study in 1973, showing that this was not the case. He did a comparative analysis of the posterior of Poterioeras and the anterior of Brachycycloceras and concluded the two could have never been connected.

 

Niko and Mapes work in 2009 and 2010 was to give Brachycloceras a full description based on the fact that it's last description assumed the two were part of the same.

 

I brought a huge conch into a museum, and the people there referred me to the Treatise passage and a huge conch specimen they had in the collections labeled Brachycycloceras. It wasn't until I asked Mapes about it that it was cleared up. His information also helped to get the huge conch in their collections named correctly.

 

It doesn't help that high-volume search result pages like this one still show a Poterioeras. It was one of the pieces of information that steered me wrong in the past.
--> https://pennsylvanianatlas.org/species/brachycycloceras-bransoni/