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BobWill

Jacksboro Texas Goniatite

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Heteromorph

So far, the closest genus that I can find is Prouddenites sp. from the Pennsylvanian Jasper Creek Shale in Texas. I am not sure if this genus has constrictions like your’s does. I am seeing a few references that it is also found in the Finis Shale, but I am not 100% sure yet. 

 

Here are the pictures that, to me, look similar to your’s. Pages 69-72: FOSSIL COLLECTING REPORT August 2013 Daniel A. Woehr

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BobWill
2 hours ago, Heteromorph said:

So far, the closest genus that I can find is Prouddenites sp. from the Pennsylvanian Jasper Creek Shale in Texas. I am not sure if this genus has constrictions like your’s does. I am seeing a few references that it is also found in the Finis Shale, but I am not 100% sure yet. 

 

Here are the pictures that, to me, look similar to your’s. Pages 69-72: FOSSIL COLLECTING REPORT August 2013 Daniel A. Woehr

I'm not sure now why I ruled out Proudenites but I may have been too hasty. They are found at Lake Bridgeport but not on the current list for Jacksboro. Dan's seems to have too few saddles and lobes in the suture and the only one I see in the Treatise is P. primus which has too many! Of course you have to take into account how much the sutures can change with growth but I can't find anything on the ontogeny of Pruddenites. There is also the flattened venter where mine is rounded. Taking another look in the Treatise I just noticed Epicanites loeblichi with a very similar suture but the closest occurrence is Oklahoma.

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Heteromorph
5 hours ago, BobWill said:

I'm not sure now why I ruled out Proudenites but I may have been too hasty. They are found at Lake Bridgeport but not on the current list for Jacksboro. Dan's seems to have too few saddles and lobes in the suture and the only one I see in the Treatise is P. primus which has too many! Of course you have to take into account how much the sutures can change with growth but I can't find anything on the ontogeny of Pruddenites. There is also the flattened venter where mine is rounded. Taking another look in the Treatise I just noticed Epicanites loeblichi with a very similar suture but the closest occurrence is Oklahoma.

Epicanites loeblichi seems to be a pretty good match. Perhaps your’s is the first occurrence of E. loeblichi in Texas.

 

The main differences that I am noticing is that your’s seems to show a constriction in Figs 2-3, especially Fig. 3, while E. loeblichi apparently doesn’t have any. Also, your’s has a more compressed whorl section than E. loeblichi, which may or may not be from post-mortem compression of your specimen. Maybe same genus but different species, or perhaps just variation within the species? Can you see any more constrictions on your specimen in person? 

 

D730F47D-7369-4DC7-BA28-3A65C5D1656F.gif.dd48d316a0172d4a3724f4dc2cd7f0b7.gif

From: Epicanites loeblichi

 

D4FAE0CA-C406-4F5C-9E9D-C3690EF709ED.thumb.jpeg.4e719b48d8ac2947c62345b9f6959ce8.jpeg

From: Ontophylogenetic Studies of Paleozoic Ammonoides

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BobWill

I just now got a chance to have another look since you mentioned the apparent constriction. I had never noticed it looking at the specimen but the image does suggest one. There are no other constrictions and that one does not appear on the other side. In fact it does not venture far past the umbilical margin. This view shows it at the red arrow  and the blue arrow shows a break in the shell nearby that also suggest the possibility of it being the result of the post-mortem distortion you mentioned.

 

WIN_20180803_22_03_05_Pro.jpg.50bd5f899f19a7e0b6d924598644e31e.jpg

 

 

Here is another look at the other side where you can see cracks but they don't appear to be constrictions as near as I can tell.

 

WIN_20180803_22_02_43_Pro.jpg.3a99f6aacb08dbd819b2afc42f57343f.jpg

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Heteromorph
14 hours ago, BobWill said:

I just now got a chance to have another look since you mentioned the apparent constriction. I had never noticed it looking at the specimen but the image does suggest one. There are no other constrictions and that one does not appear on the other side. In fact it does not venture far past the umbilical margin. This view shows it at the red arrow  and the blue arrow shows a break in the shell nearby that also suggest the possibility of it being the result of the post-mortem distortion you mentioned.

 

WIN_20180803_22_03_05_Pro.jpg.50bd5f899f19a7e0b6d924598644e31e.jpg

 

 

Here is another look at the other side where you can see cracks but they don't appear to be constrictions as near as I can tell.

 

WIN_20180803_22_02_43_Pro.jpg.3a99f6aacb08dbd819b2afc42f57343f.jpg

Thanks! So it isn’t a constriction, but just an artifact of post-mortem compression. And if it were a constriction there would be others, but there aren’t. 

 

This matches very nicely with the whorl profile and suture morphology of E. loeblichi. I would say that it is E. loeblichi, but I would be interested to see what a goniatite expert says. If you do send pictures to one, please let us know what they say. If it does turn out to be something new for Jacksboro or even Texas, I would love to see it in the next version of the Pictorial Guide to the Upper Pennsylvanian Fossils of Texas.

 

By the way, it is a lovely specimen! The pyritized goniatites that I have found from Jacksboro are always exquisitely detailed.

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Heteromorph

@BobWill,

 

I was presumptuous in my identification of E. loeblichi. Your specimen is Uddenites oweni, a species well reported from the Finis Shale. For some reason I didn’t look at the link you posted to the DPS’ Pictorial Guide to Upper Pennsylvanian Fossils at first, but when I did I realized what you specimen is. It has a very good figure of U. oweni on page 4 from Miller & Downs 1950, one of the same specimens shown in Fig. 5. 

 

First of all, E. leoblichi has been reassigned to the genus Praedaraelites (Korn & Titus 2011, Page 183), but the separation of Epicanites and Praedaraelites is used tentatively because, “The only difference between the two genera is the presence or absence of lobe serration, a character that may be only of specific value.” What I do know is that neither genera are reported anytime after the lower Pennsylvanian, with Epicanites being reported from the Brigantian of the middle Mississippian to the Marsdenian of the early Pennsylvanian (about 336 Ma to 315.5 Ma), and Praedaraelites being reported from the Asbian of the middle Mississippian to the Arnsbergian of the late Mississippian (about 337 Ma to 325 Ma). The Finis Shale is dated to be early middle Virgilian, about 304 to 303 Ma, which puts roughly 12.5 Ma between the last occurrence of Epicanites and your specimen, and 22 Ma between the last occurrence of Praedaraelites and your specimen. 

 

Secondly, your specimen lines up very nicely with the morphology of U. oweni. U. oweni is very evolute in juvenile ontogeny, lacks any constrictions, and in juvenile ontogeny has basically the same suture morphology as your’s. Even though the sutures in the mature ontogeny of U. oweni are very different from your specimen, according to Miller & Downs 1950, the sutures differ considerably between specimens, different ontogenies, and distortion due to crushing. Your specimen fits within U. oweni’s range of juvenile suture variation quite well. For more information, see Figs 1-5. 

 

Your specimen is a juvenile U. oweni that is young enough to not have a grooved venter yet and to have a relatively simple suture. That also explains why I at first mistook it for Prouddenites sp., since that is the ancestor of U. oweni

 

6F31D080-43CC-4D38-B5AA-569A0B39D5AB.thumb.jpeg.7d8e37db79e7d5d7f16a4a1e1dd72be0.jpeg

Fig. 1.

 

81973C31-B87E-460A-ADEF-DCB52E2E00AD.thumb.jpeg.1348f5bd1d9d4991e1d13dd9d44b1024.jpeg

Fig. 2. 

 

94A48C96-1EE4-4E7F-B65E-496C946DC14F.thumb.jpeg.95de89e59ee74a8bc8ce9c2fe30bdc5e.jpeg

Fig. 3

 

472E730B-82F5-4A36-A516-3C5BFF6CB8F1.thumb.jpeg.08204281e6b71225ac73189ec0cb7e3c.jpeg

Fig. 4. 

 

6F5BA4A3-B675-4C77-9800-16B19FEAC173.thumb.jpeg.982d101f13cab3077a3f10bf239fff2c.jpeg

Fig. 5.

 

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Heteromorph

Does anyone know whether Uddenites oweni is still a valid species? The more I look at U. oweni and U. schucherti the more I am wondering if they are synonymous. I don't see any reference to U. oweni on Fossilworks, and I also don't see much reference to it anywhere apart from Miller & Furnish 1940 and Miller & Downs 1950. The only mentions of the genus Uddenites in the hard copy version of the Color Guide to Pennsylvanian Fossils of North Texas is U. schucherti and U. harlani, which are both listed as being from the Finis Shale. Of the two, U. schucherti matches Bob's specimen very well. Also, the mature suture of U. schucherti as seen here is basically identical to the mature suture of U. oweni in my Fig. 3. 

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BobWill
On 8/15/2018 at 4:57 PM, Heteromorph said:

@BobWill,

 

I was presumptuous in my identification of E. loeblichi. Your specimen is Uddenites oweni, a species well reported from the Finis Shale. For some reason I didn’t look at the link you posted to the DPS’ Pictorial Guide to Upper Pennsylvanian Fossils at first, but when I did I realized what you specimen is. It has a very good figure of U. oweni on page 4 from Miller & Downs 1950, one of the same specimens shown in Fig. 5. 

 

First of all, E. leoblichi has been reassigned to the genus Praedaraelites (Korn & Titus 2011, Page 183), but the separation of Epicanites and Praedaraelites is used tentatively because, “The only difference between the two genera is the presence or absence of lobe serration, a character that may be only of specific value.” What I do know is that neither genera are reported anytime after the lower Pennsylvanian, with Epicanites being reported from the Brigantian of the middle Mississippian to the Marsdenian of the early Pennsylvanian (about 336 Ma to 315.5 Ma), and Praedaraelites being reported from the Asbian of the middle Mississippian to the Arnsbergian of the late Mississippian (about 337 Ma to 325 Ma). The Finis Shale is dated to be early middle Virgilian, about 304 to 303 Ma, which puts roughly 12.5 Ma between the last occurrence of Epicanites and your specimen, and 22 Ma between the last occurrence of Praedaraelites and your specimen. 

 

Secondly, your specimen lines up very nicely with the morphology of U. oweni. U. oweni is very evolute in juvenile ontogeny, lacks any constrictions, and in juvenile ontogeny has basically the same suture morphology as your’s. Even though the sutures in the mature ontogeny of U. oweni are very different from your specimen, according to Miller & Downs 1950, the sutures differ considerably between specimens, different ontogenies, and distortion due to crushing. Your specimen fits within U. oweni’s range of juvenile suture variation quite well. For more information, see Figs 1-5. 

 

Your specimen is a juvenile U. oweni that is young enough to not have a grooved venter yet and to have a relatively simple suture. That also explains why I at first mistook it for Prouddenites sp., since that is the ancestor of U. oweni

 

 

 

.

 

Thanks for locating the information on the ontogeny of Uddenites. This is what Dr. Neuman suggested too but we hadn't found that reference yet to confirm the ID and Epicanites was the next closest thing I could find. I missed seeing the age difference.

 

1 hour ago, Heteromorph said:

Does anyone know whether Uddenites oweni is still a valid species? The more I look at U. oweni and U. schucherti the more I am wondering if they are synonymous. I don't see any reference to U. oweni on Fossilworks, and I also don't see much reference to it anywhere apart from Miller & Furnish 1940 and Miller & Downs 1950. The only mentions of the genus Uddenites in the hard copy version of the Color Guide to Pennsylvanian Fossils of North Texas is U. schucherti and U. harlani, which are both listed as being from the Finis Shale. Of the two, U. schucherti matches Bob's specimen very well. Also, the mature suture of U. schucherti as seen here is basically identical to the mature suture of U. oweni in my Fig. 3. 

 Dr. Neuman has been gathering all the papers he can find on these for his Pictorial Guide... so maybe he can get a firm answer about the validity of the species. We have been offered help from Royal Mapes and others for our little study group putting together the guide so maybe it's time to tap into that resource. Once we get scale information and some text where needed we hope to make the guide available. We still have trilobites and vertebrates ect. to add but it's coming along nicely. You might like to join us tomorrow at the U.T.Arlington GeoScience building room 202 at 9AM for the next meeting. Dr. Nestell is helping out. Anyone with an interest is welcome.

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Heteromorph
1 hour ago, BobWill said:

You might like to join us tomorrow at the U.T.Arlington GeoScience building room 202 at 9AM for the next meeting. Dr. Nestell is helping out. Anyone with an interest is welcome.

Thanks! I will probably take you up on that offer. Do you plan on bringing this goniatite? I would like to see it in person. 

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BobWill
32 minutes ago, Heteromorph said:

Thanks! I will probably take you up on that offer. Do you plan on bringing this goniatite? I would like to see it in person. 

Yes, Ben Neumen wanted a closer look at it too. We always take along our newest mystery fossils.

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