DMcLY Posted May 15, 2020 Share Posted May 15, 2020 Amateur here; turned over a rock in our landscape for 20+ years, to find this. Obtained at Duff’s Quarry in Huntsville Ohio. What kind of seashell is this - strange circular arc on hinge side? Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 15, 2020 Share Posted May 15, 2020 These are the interiors of the concave pedicle valves of the brachiopod Strophomena. Very nice too. 10 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Kane Posted May 15, 2020 Share Posted May 15, 2020 Nice piece! Welcome to the Forum. These look like Devonian age Strophodonta sp., but I’m rubbish on brachiopod IDs. Let me tag our brachiophile, @Tidgy's Dad ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Kane Posted May 15, 2020 Share Posted May 15, 2020 @Tidgy's Dad we must have been typing at the same time! Edit: and, yes, Strophomena, not Strophodonta. 1 ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 15, 2020 Share Posted May 15, 2020 1 minute ago, Kane said: @Tidgy's Dad we must have been typing at the same time! Indeed, lots of bleeps from my laptop. Strophomena planoconvexa, prob'ly. 2 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
DMcLY Posted May 15, 2020 Author Share Posted May 15, 2020 Wow! You guys are THE BEST! Hubs brought tons of fieldstone rocks home from this quarry to cement paths all around our house. This piece must have popped off a bigger rock - he’d have never bothered picking up such a small piece. For some reason I picked this up today, turning it over for the first time. Same quarry source where another rock we were laying cleaved in half to expose the “skeleton” of a large leaf - I cold roll the fiber of it between my fingers, it was that “fresh”. We love our rocks! Can’t thank you enough for your answers! Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 15, 2020 Share Posted May 15, 2020 27 minutes ago, DMcLY said: Wow! You guys are THE BEST! Hubs brought tons of fieldstone rocks home from this quarry to cement paths all around our house. This piece must have popped off a bigger rock - he’d have never bothered picking up such a small piece. For some reason I picked this up today, turning it over for the first time. Same quarry source where another rock we were laying cleaved in half to expose the “skeleton” of a large leaf - I cold roll the fiber of it between my fingers, it was that “fresh”. We love our rocks! Can’t thank you enough for your answers! These rocks are Upper Ordovician, roughly 445 to 450 million years old. Leaves and land plants had not yet evolved. So if you found a leaf it must have been from elsewhere or the soil layers at the top of the quarry. 3 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
DMcLY Posted May 15, 2020 Author Share Posted May 15, 2020 Leaf was definitely not in soil, but sandwiched perfectly between hard sedimentary rock. Link to comment Share on other sites More sharing options...
Kane Posted May 15, 2020 Share Posted May 15, 2020 Can we see the leaf? Sorry for misidentifying as Devonian. I’ve been making bad calls more frequently as of late. ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
DMcLY Posted May 15, 2020 Author Share Posted May 15, 2020 I’m sure I took at least a phone pic of it. Will look for it in my archives, might take a few days. Link to comment Share on other sites More sharing options...
minnbuckeye Posted May 15, 2020 Share Posted May 15, 2020 Very nice find!!! To me it is one of the prettiest brachiopods I find. What your plate of Strophomena shows is the inner surface of the shells. The circular area is where the muscle attachment occurred. They must have been strong brachiopods!!! Photo from the Wisconsin Geological and Natural History. 1 Link to comment Share on other sites More sharing options...
DMcLY Posted May 15, 2020 Author Share Posted May 15, 2020 Minnbuckeye, found this page on the https://wgnhs.wisc.edu/ website - thank you so much! Still trying to understand (you're way ahead of me in this department) how the convex ribbed structures on my rock can be of the inside "inner structures" of the shell. I so appreciate you pointing me to the wisc.edu site. And to answer Kane, who asked for a picture of the "leaf skeleton" we found when a rock cleaved in half - here 'tis: Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 15, 2020 Share Posted May 15, 2020 Those would appear to be modern root structures that have forced their way into a gap between the bedding planes of the rock. 1 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
DMcLY Posted May 15, 2020 Author Share Posted May 15, 2020 Sounds good to me - thanks for your response! Link to comment Share on other sites More sharing options...
Misha Posted May 15, 2020 Share Posted May 15, 2020 Beautiful brachiopods! Link to comment Share on other sites More sharing options...
Harry Pristis Posted May 15, 2020 Share Posted May 15, 2020 It does appear to be Strophomena sp., an Ordovician to Devonian form. Huntsville, Logan County, is well into the Silurian bedrock area of the state. There is an isolated outcrop of Devonian in the center of the county. (See the little 'island' of Devonian on the Findlay Arch in the map below -- that's in Logan County.) So, Kane could have been correct when he guessed Devonian, but Silurion is my guess. 2 http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
minnbuckeye Posted May 15, 2020 Share Posted May 15, 2020 7 hours ago, DMcLY said: Still trying to understand (you're way ahead of me in this department) how the convex ribbed structures on my rock can be of the inside "inner structures" of the shell. I know a few years ago when I knew nothing, it was pointed out to me and I was perplexed. So I am passing on my education to you. Now take it and pass it to the next newbie that posts a Strophomena!!!! Mike Link to comment Share on other sites More sharing options...
cngodles Posted May 16, 2020 Share Posted May 16, 2020 7 hours ago, DMcLY said: how the convex ribbed structures on my rock can be of the inside "inner structures" of the shell. As I understand it, even if you have a closed shell with air inside if it, over the course of over 400 million years, minerals and sediment are going to get in there. It literally will permeate through the shell and into the void. This preserves the inside in high detail as well. I collect Cephalopods, and I still haven’t found a single one with a preserved pocket of air, just solid rock. Most marine fossils are a replacement of the original shell. Most are replaced with the mineral calcite here, however being younger Carboniferous (305) there are many that still have original aragonite shell material. Some younger ones and ones in unique matrix will have crystal covered geode like chambers in the voids. All subject to forum peer review, I’ve only been at this for about 18 months. 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 May 16, 2020 Share Posted May 16, 2020 4 hours ago, Harry Pristis said: So, Kane could have been correct when he guessed Devonian, but Silurion is my guess. Nope, 'fraid not. These are Ordovician Strophomena, could be one of several species, but the later species look markedly different and are comparatively rare. This quarry is listed as being Silurian dolostone, but these are Ordovician, perhaps from somewhere else? They have been 20 years in the garden after all. Anyway, if these are Silurian, I'll eat my fes. 3 Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Kane Posted May 16, 2020 Share Posted May 16, 2020 I defer to Adam on this. He knows his brachs much more than I do, and I was only reflecting on the general state (which has some lovely Devonian deposits!). I’m more a trilobite guy. 1 ...How to Philosophize with a Hammer Link to comment Share on other sites More sharing options...
Jeffrey P Posted May 16, 2020 Share Posted May 16, 2020 Those look exactly like the Ordovician Strophomena brachiopods I collected at St. Leon (Indiana) last year. 3 Link to comment Share on other sites More sharing options...
Fossildude19 Posted May 16, 2020 Share Posted May 16, 2020 3 Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Harry Pristis Posted May 16, 2020 Share Posted May 16, 2020 18 hours ago, Fossildude19 said: This illustration is without identifying a cast, and mis-labelling casts as "internal mould." This will just add to the confusion, I fear. A mold is empty; a cast is what fills in a mold. If you press the outside of a clam shell into clay, you've produced an external mold of the clam shell in the clay. If you press clay into the inside of a clam shell, you've produced an internal cast of the clam shell. Thus, the sediments that filled the fossil snail above produced an internal CAST of the snail shell. Same with the fossil clam above: the sediments that filled the clam shell produced an internal CAST. A plaster shell around a broken limb is NOT a cast (as we're speaking of molds and casts here), it is an exterior MOLD of the limb. A jello mold is the metal pan into which the liquid gelatin is poured. The resulting loaf of jello is an internal CAST of the metal pan. 1 http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
Tidgy's Dad Posted May 16, 2020 Share Posted May 16, 2020 1 hour ago, Jeffrey P said: Those look exactly like the Ordovician Strophomena brachiopods I collected at St. Leon (Indiana) last year. Yup. From my collection from that location : Life's Good! Tortoise Friend. Link to comment Share on other sites More sharing options...
Harry Pristis Posted May 16, 2020 Share Posted May 16, 2020 1 hour ago, Tidgy's Dad said: Nope, 'fraid not. These are Ordovician Strophomena, could be one of several species, but the later species look markedly different and are comparatively rare. This quarry is listed as being Silurian dolostone, but these are Ordovician, perhaps from somewhere else? They have been 20 years in the garden after all. Anyway, if these are Silurian, I'll eat my fes. I decided to accept the OP's account of the fossils. If we accept an Ordovician age for the fossils, they could easily be from a little south of Huntsville in the Late Ordovician Cincinnatian Series, likely the Richmondian Stage. Strophomena nutans is abundant in the Ft. Ancient Member of the Waynesville Formation. http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
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