Lucid_Bot Posted November 1, 2022 Share Posted November 1, 2022 Hello, found what I think are nautiloids and brachiopods. I found the rock in a stream and I can't say what limestone (maybe brush creek or pine creek), but the area is Glenshaw Formation in northern Allegheny County, Pennsylvania. It's quite difficult for me to get good pictures, let alone good pictures with scale, so I'll tell you that the first two pictures are 2 cm (same organism), the second is 5.5 cm and the largest Nautilus in the last pictures is about 6 cm. All information is appreciated, thanks! 3 Link to comment Share on other sites More sharing options...
ClearLake Posted November 1, 2022 Share Posted November 1, 2022 I am going to say that the first brachiopod is a Derbyia and the second is a Linoproductus based on wrinkling that I think I am seeing near the posterior edges. ID's on both are made a bit more difficult by the not preserved or not visible hinge line. Lets see what @cngodles or @Tidgy's Dad have to say as they both are probably more familiar with these than I am. 2 1 Link to comment Share on other sites More sharing options...
Misha Posted November 2, 2022 Share Posted November 2, 2022 I think the first is not Derbiya sp. but the brachial valve to a productid. The nautiloid is Metacoceras I think. 2 2 Link to comment Share on other sites More sharing options...
ClearLake Posted November 2, 2022 Share Posted November 2, 2022 4 minutes ago, Misha said: I think the first is not Derbiya sp. but the brachial valve to a productid That could be as I just noticed the wrinkling on that one in the lower right of the second picture after you had me take a second look. I thought the first picture looked too elevated for a productid brachial, but maybe not. Link to comment Share on other sites More sharing options...
cngodles Posted November 2, 2022 Share Posted November 2, 2022 (edited) That is Metacoceras for sure. The genus is a bit of a garbage taxon with several species named. It’s easily one of the two most common cephalopods in this formation, with only Pseudorthoceras able to challenge it. You are looking at mostly a steinkern; the black lines are the inside attachments of the camerae to the shell walls. They don’t retain that thickness throughout. They can be quite interesting individually in steinkern form. Edited November 2, 2022 by cngodles 3 Fossils of Parks Township - Research | Catalog | How-to Make High-Contrast Photos Link to comment Share on other sites More sharing options...
Thomas.Dodson Posted November 2, 2022 Share Posted November 2, 2022 5 hours ago, Misha said: I think the first is not Derbiya sp. but the brachial valve to a productid. I agree. It seems similar to some Leptaena sp. I agree with Metacoceras and Linoproductus for the others. 1 1 Link to comment Share on other sites More sharing options...
DPS Ammonite Posted November 2, 2022 Share Posted November 2, 2022 10 minutes ago, Thomas.Dodson said: It seems similar to some Leptaena sp. Probably not Leptaena since it died out in the Early Mississippian; formation claimed to be Pennsylvanian by OP. 2 2 My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
DPS Ammonite Posted November 2, 2022 Share Posted November 2, 2022 (edited) A slight side note; that is a weird pattern on the purported Linoproductus. I wonder if the brachiopod was injured and then healed, disturbing the normally radial ribs of the brachiopod. @Tidgy's Dad Edited November 2, 2022 by DPS Ammonite 1 1 My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
hemipristis Posted November 2, 2022 Share Posted November 2, 2022 I have not seen nautiloids from Pennsylvania. Very nice! 1 1 'Those who cannot remember the past are condemned to repeat it.' George Santayana Link to comment Share on other sites More sharing options...
Lucid_Bot Posted November 2, 2022 Author Share Posted November 2, 2022 Thanks to everyone who has posted. Just wondering, nearly all of the fossils I find in limestone are incomplete or poorly preserved; is this typical of the limestone around here, am I just getting lucky, am I doing something wrong? This rock is very hard and brittle and resists clean splits. Link to comment Share on other sites More sharing options...
Lucid_Bot Posted November 2, 2022 Author Share Posted November 2, 2022 6 hours ago, DPS Ammonite said: Probably not Leptaena since it died out in the Early Mississippian; formation claimed to be Pennsylvanian by OP. Yes, Mississippian rocks are far from my location. Almost certainly Pennsylvanian. Link to comment Share on other sites More sharing options...
hemipristis Posted November 2, 2022 Share Posted November 2, 2022 22 minutes ago, Lucid_Bot said: Thanks to everyone who has posted. Just wondering, nearly all of the fossils I find in limestone are incomplete or poorly preserved; is this typical of the limestone around here, am I just getting lucky, am I doing something wrong? This rock is very hard and brittle and resists clean splits. I believe location may have something to do with it. Consider the ages of the limestones in the Appalachians, and the tectonic history: they felt the effects of both Europe and Africa mashing into them, and responded in kind with the folds and faults that you see in the field. I'm not the expert in fossil hunting in the Appalachians by any stretch, but in my fossilizing jaunts in the Appalachians it seems that fossil preservation is better to the north in New York, and to the south in Tennessee than in the mid-Atlantic states. I'd be curious to hear the input from folks that collect in that region regularly 2 'Those who cannot remember the past are condemned to repeat it.' George Santayana Link to comment Share on other sites More sharing options...
cngodles Posted November 2, 2022 Share Posted November 2, 2022 7 hours ago, Lucid_Bot said: Just wondering, nearly all of the fossils I find in limestone are incomplete or poorly preserved; https://fossil.15656.com/2021/05/04/the-3-preservation-types-of-glenshaw-formation-fossil-marine-fauna/ 2 Fossils of Parks Township - Research | Catalog | How-to Make High-Contrast Photos Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 7, 2022 Share Posted November 7, 2022 Nothing to add, really. Great nautiloid. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted November 7, 2022 Share Posted November 7, 2022 (edited) On 11/2/2022 at 5:59 AM, DPS Ammonite said: A slight side note; that is a weird pattern on the purported Linoproductus. I wonder if the brachiopod was injured and then healed, disturbing the normally radial ribs of the brachiopod. @Tidgy's Dad Yes, I think that is very likely the case. Quite common on later Palaeozoic specimens especially. Edited November 7, 2022 by Tidgy's Dad 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
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