TheInvertebrateGuy Posted July 3, 2022 Share Posted July 3, 2022 I recently found a fossil in my backyard and I’m not sure what it could be. I live in a place where the bedrock dates back to the Devonian. Hopefully this will be the only fossil id that I’ll ever do. Front Back Left Right Top Bottom If you notice in the front, top, and right images, there is a brachiopod mold, which means the fossil was either from the shoreline or from underwater. I also think that, at this point, the fossil comes from the lower Devonian. Link to comment Share on other sites More sharing options...
abyssunder Posted July 3, 2022 Share Posted July 3, 2022 Welcome to the Forum! I think you have a coral there. 2 " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 3, 2022 Share Posted July 3, 2022 2 hours ago, TheInvertebrateGuy said: Hopefully this will be the only fossil id that I’ll ever do. Aww, never say never! You appear to have a fossilised coral belonging to the extinct order(*1) Rugosa. Known as the rugose corals, sometimes referred to as horn corals, they existed for ages, from the Palaeozoic ~480mya (480 millions of years ago/old) to the Late Cretaceous(**2) ~70mya. (*1): It is still heavily debated over whether Rugosa is an order or subclass, a paper by Brownlaw and Jell, 2008 stated that it should be a subclass (I can't seem to find more recent opinions, but I know there are lots) (**2): Order Stauriida is the only sub-taxa to contain members dating back to this recently - Cystiphyllida has members from the Early Jurassic (~190mya), but the vast majority went extinct at the end of the Permian, ~265mya. If you supply more precise geologic information about where it was collected, someone may be able to provide a further ID! ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
TheInvertebrateGuy Posted July 3, 2022 Author Share Posted July 3, 2022 1 minute ago, IsaacTheFossilMan said: Aww, never say never! You appear to have a fossilised coral belonging to the extinct order(*1) Rugosa. Known as the rugose corals, sometimes referred to as horn corals, they existed for ages, from the Palaeozoic ~480mya (480 millions of years ago/old) to the Late Cretaceous(**2) ~70mya. (*1): It is still heavily debated over whether Rugosa is an order or subclass, a paper by Brownlaw and Jell, 2008 stated that it should be a subclass (I can't seem to find more recent opinions, but I know there are lots) (**2): Order Stauriida is the only sub-taxa to contain members dating back to this recently - Cystiphyllida has members from the Early Jurassic (~190mya), but the vast majority went extinct at the end of the Permian, ~265mya. If you supply more precise geologic information about where it was collected, someone may be able to provide a further ID! Thanks for the info! I will supply a bit of more geological info for the fossil. If I could get links to some of the papers I would love that. Also, don’t worry, I fossil id a lot. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 3, 2022 Share Posted July 3, 2022 19 minutes ago, TheInvertebrateGuy said: Thanks for the info! I will supply a bit of more geological info for the fossil. If I could get links to some of the papers I would love that. Also, don’t worry, I fossil id a lot. It seems most modern papers cite Rugosa as a subclass. New Rugosa taxa from the Middle Devonian Subpolar Urals (researchgate.net) [PDF] Early Carboniferous Chinese and Australian „Siphonodendron” (Anthozoa, Rugosa): ecological and geographical influence on taxonomy | Semantic Scholar Most (can't guarantee all) papers mentioning Rugosa can be found here: Rugosa (fossiilid.info) ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
TheInvertebrateGuy Posted July 3, 2022 Author Share Posted July 3, 2022 Here’s the area around in which I found the fossil on a geological map. The rock is definitely limestone, it’s also nearly halfway metamorphosed into marble on the bottom, though I’m not that sure if that is entirely right. The fossil being limestone is the reason as to why I also believe its from the lower Devonian. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 3, 2022 Share Posted July 3, 2022 2 minutes ago, TheInvertebrateGuy said: Here’s the area around in which I found the fossil on a geological map. The rock is definitely limestone, it’s also nearly halfway metamorphosed into marble on the bottom, though I’m not that sure if that is entirely right. The fossil being limestone is the reason as to why I also believe its from the lower Devonian. Could it not be Silurian, by this metric? Do you have the exact place you found it, such that we may get a stratigraphic unit? ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
TheInvertebrateGuy Posted July 4, 2022 Author Share Posted July 4, 2022 2 hours ago, IsaacTheFossilMan said: Could it not be Silurian, by this metric? Do you have the exact place you found it, such that we may get a stratigraphic unit? Good question. Sorry for the wait, your question on if I could get a stratigraphic unit had me wondering, so I had gone to the same area where I found the previous fossil and found more fossils that I cannot identify too well either. The only ones I was able to identify, though, were parts of crinoid stems, which shows that the fossils were preserved in the ocean, more specifically, the Rheic ocean, where the area I found the fossils was. The Rheic ocean was separating Gondwana and Laurussia (not Laurasia) which were 2 supercontinents that existed during the Devonian (though eventually they would collide together to form the supercontinent Pangaea 120 million years after the Devonian). By finding such fossils, I have determined that glacial erosion by the current ice age has eroded bedrock down by roughly 400 million years (also explains why land in Indiana is flat). I have also pinpointed the exact location of the area where I found the fossils on a geological map and it indeed is Devonian (the red dot near the top-left corner is where I found the fossils. Another note to take is that the ozone layer had formed during the Devonian. This brings more possibilities as to what the fossil I found was. Was it terrestrial, or was it aquatic?(I believe it was aquatic). If you want images of the new fossils that I found I will happily post them in this topic or in another topic. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 4, 2022 Share Posted July 4, 2022 It's definitely aquatic; you have a rugose coral on your hands! Given the position, it could either be the Muscatatuck Group or the Antrim Shale. Given the type of rock, it's most likely the Muscatatuck Group, which is Major:{limestone,dolostone}. This would make your fossil(s) 419.2-358.9mya. Zaphrentis phrygia is a possible ID, being known from nearby. ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
TheInvertebrateGuy Posted July 4, 2022 Author Share Posted July 4, 2022 Great information! I believe that the fossil comes from the Muscatatuck Group because of the limestone deposits scattered throughout the area it covers. I also believe that Zaphrentis phrygia is a great identification due to its similar morphology. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 4, 2022 Share Posted July 4, 2022 13 minutes ago, TheInvertebrateGuy said: Great information! I believe that the fossil comes from the Muscatatuck Group because of the limestone deposits scattered throughout the area it covers. I also believe that Zaphrentis phrygia is a great identification due to its similar morphology. What you have is a Steinkern (Deutsch: sht-eye-n-k-air-n) - an internal mould or cast of the original fossil, which would have been filled with matrix and dissolved away! ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
TheInvertebrateGuy Posted July 4, 2022 Author Share Posted July 4, 2022 28 minutes ago, IsaacTheFossilMan said: What you have is a Steinkern (Deutsch: sht-eye-n-k-air-n) - an internal mould or cast of the original fossil, which would have been filled with matrix and dissolved away! Interesting find! Seems to be a Steinkern of the same Rugose coral identification, Zaphrentis phryiga, whose body would’ve been broken prior to mineralization of the internal cast. Link to comment Share on other sites More sharing options...
IsaacTheFossilMan Posted July 4, 2022 Share Posted July 4, 2022 (edited) 1 hour ago, TheInvertebrateGuy said: Interesting find! Seems to be a Steinkern of the same Rugose coral identification, Zaphrentis phryiga, whose body would’ve been broken prior to mineralization of the internal cast. Indeed, although the internal cast isn't mineralised, per say, as it isn't biological material, but silt. Edited July 4, 2022 by IsaacTheFossilMan ~ Isaac; www.isaactfm.com "Don't move! He can't see us if we don't move!" - Alan Grant Come to the spring that is The Fossil Forum, where the stream of warmth and knowledge never runs dry. Link to comment Share on other sites More sharing options...
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