KimTexan Posted March 12, 2018 Share Posted March 12, 2018 I went out to the North Sulfur River (NSR) yesterday and went down a particular feeder creek. Along the creek I kept finding clam shells that looked modern, but not like any fresh water clam that I’ve ever seen before. I have never seen this category of preservation of clams in the NSR or elsewhere in Texas for that matter. The formation out there is Ozan of the Cretaceous. If they are Cretaceous they are quite remarkably well preserved. There are 2 varieties of clams as best I can tell. There is the smaller one that is smooth and then the larger that have a wavy or ruffled shell. Both have fairly heavy, thick shells that are a beautiful soft pink/baige pearly color. Here are the smaller smooth ones. One up close. Here are the ones with wavy shells. I also found 2 modern fresh water clam shells that are common in Texas . Their shells are pretty thin and light. Anyway, can anyone tell me if the first 2 kinds are even fresh water? If so I have never seen a fresh water clam like them. I think they are Cretaceous, but I have never seen such preservation in Texas. Any thoughts or comments would be appreciated. Link to comment Share on other sites More sharing options...
Rockwood Posted March 12, 2018 Share Posted March 12, 2018 Just a hunch: Cretaceous fossil. The smooth one that is. Link to comment Share on other sites More sharing options...
-AnThOnY- Posted March 12, 2018 Share Posted March 12, 2018 They all look modern to me. Link to comment Share on other sites More sharing options...
KimTexan Posted March 12, 2018 Author Share Posted March 12, 2018 18 minutes ago, -AnThOnY- said: They all look modern to me. Do you know of any Texas fresh water clams that look like that? I’ve spent my whole life living in the South hiking in creeks anywhere from Virginia, Florida, Mississippi, Tennessee, Alabama, Texas and Arkansas and I have never seen a fresh water clam like that. I’ve hike spots across North America for that matter, with the exception of New England and north of there and never seen a fresh water clam like the wavy one. The preservation looks modern, but the two modern clams aren’t chipped and they’re thin and fragile. The thick, heavy ones are all chipped, which makes me think they have been around a long time. I just saw Dan’s, @Uncle Siphuncle post about the mammoth tusk. I now tend to think that they could be Pleistocene that washed into the creek. That would make more sense than Cretaceous. Link to comment Share on other sites More sharing options...
thair Posted March 12, 2018 Share Posted March 12, 2018 Kim The wavy one is modern if that's the one you are asking about. I have found living ones like those in Lake Brownwood. One thing to note however is these can also be found in Indian campsites quite a distance form a water source. Link to comment Share on other sites More sharing options...
Uncle Siphuncle Posted March 12, 2018 Share Posted March 12, 2018 I’d wager modern. Grüße, Daniel A. Wöhr aus Südtexas "To the motivated go the spoils." Link to comment Share on other sites More sharing options...
-AnThOnY- Posted March 12, 2018 Share Posted March 12, 2018 31 minutes ago, KimTexan said: Do you know of any Texas fresh water clams that look like that? I’ve spent my whole life living in the South hiking in creeks anywhere from Virginia, Florida, Mississippi, Tennessee, Alabama, Texas and Arkansas and I have never seen a fresh water clam like that. I’ve hike spots across North America for that matter, with the exception of New England and north of there and never seen a fresh water clam like the wavy one. The preservation looks modern, but the two modern clams aren’t chipped and they’re thin and fragile. The thick, heavy ones are all chipped, which makes me think they have been around a long time. I just saw Dan’s, @Uncle Siphuncle post about the mammoth tusk. I now tend to think that they could be Pleistocene that washed into the creek. That would make more sense than Cretaceous. I've seen them in the Trinity with pronounced ribs on them like that. I will agree, however, that it is certainly possible that they could be Indian campsite related. Link to comment Share on other sites More sharing options...
Herb Posted March 12, 2018 Share Posted March 12, 2018 They look modern to me also, though you can get Cretaceous shells that are preserved like that "Absence of evidence is not evidence of absence"_ Carl Sagen No trees were killed in this posting......however, many innocent electrons were diverted from where they originally intended to go. " I think, therefore I collect fossils." _ Me "When you have eliminated the impossible, whatever remains, however improbable, must be the truth."__S. Holmes "can't we all just get along?" Jack Nicholson from Mars Attacks Link to comment Share on other sites More sharing options...
KimTexan Posted March 12, 2018 Author Share Posted March 12, 2018 Let’s not take the preservation into account. If we can identify the species then we will have the answer. The last time I had this dilemma it was Cameleolopha bellaplicata oysters in Post Oak Creek which a number of people told me they were modern. I thought they were Pleistocene, but turned out to be Turonian, upper Cretaceous in age. The preservation seemed too good for that, but you can’t argue with a defined species and established period it shows up in. Who are some good bivalve people on here? Maybe @Ludwigia, @fifbrindacier Or @DPS Ammonite have some thoughts. @abyssunder can almost always come up with a reference. Link to comment Share on other sites More sharing options...
Peat Burns Posted March 12, 2018 Share Posted March 12, 2018 They both look like Unionidae. The first one reminds me of Amblema plicata. Without looking it up, I don't know if they are found in your area of Texas, but this would be one to compare to and check range / distribution. Link to comment Share on other sites More sharing options...
abyssunder Posted March 12, 2018 Share Posted March 12, 2018 Maybe they are Unionidae bivalves. Peat beat me to it. " 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...
Peat Burns Posted March 12, 2018 Share Posted March 12, 2018 The second one might be Pyganodon grandis. Again, this is off the top of my head, and just a suggestion for you to follow up on Also, you may wish to check with Texas state law. I know that in Michigan it is illegal to take any unionid shells, even if dead ,without a permit. It is unfortunate, but there are unscrupulous people who take them live, and there is no way to tell that a dead shell that has been cleaned was not taken alive. Many of the unionid mussels are in extreme Danger. Link to comment Share on other sites More sharing options...
JohnJ Posted March 13, 2018 Share Posted March 13, 2018 Not sure of the species @KimTexan but I have seen both types, with their live creators, many times in Texas rivers and creeks. The human mind has the ability to believe anything is true. - JJ Link to comment Share on other sites More sharing options...
Fruitbat Posted March 13, 2018 Share Posted March 13, 2018 The ones with the 'wavy' shells definitely remind me of Amblema plicata (kudos to @Peat Burns) , the 'Threeridge' mussel (one of the Unionidae), which is currently extant in the North Sulphur River (though not common). I have found fairly large concentrations of these in some of the Late Pleistocene/Early Holocene sediments near the Hwy.24 bridge. The smaller, smoother ones may be Lampsilis radiata, another member of the Unionidae which is also locally common in Late Pleistocene/Holocene sediments on the NSR. Shells of this mussel are also relatively abundant in certain areas. Back in the 1980s, a friend of mine and I found a largely-complete skeleton of Bison antiquus resting on a layer of both of these mussels in the bank of the NSR close to the Hwy.24 bridge. The late Chuck Finsley of the Dallas Museum of Natural History (now the Perot Museum) submitted them to one of his experts who identified them. Apparently they were among the favorite mussels used for food by the Native Americans who used to inhabit the area. -Joe Illigitimati non carborundum Fruitbat's PDF Library Link to comment Share on other sites More sharing options...
KimTexan Posted March 13, 2018 Author Share Posted March 13, 2018 1 hour ago, Fruitbat said: The ones with the 'wavy' shells definitely remind me of Amblema plicata (kudos to @Peat Burns) , the 'Threeridge' mussel (one of the Unionidae), which is currently extant in the North Sulphur River (though not common). I have found fairly large concentrations of these in some of the Late Pleistocene/Early Holocene sediments near the Hwy.24 bridge. The smaller, smoother ones may be Lampsilis radiata, another member of the Unionidae which is also locally common in Late Pleistocene/Holocene sediments on the NSR. Shells of this mussel are also relatively abundant in certain areas. Back in the 1980, a friend of mine and I found a largely-complete skeleton of Bison antiquus resting on a layer of both of these mussels in the bank of the NSR close to the Hwy.24 bridge. The late Chuck Finsley of the Dallas Museum of Natural History (now the Perot Museum) submitted them to one of his experts who identified them. Apparently they were among the favorite mussels used for food by the Native Americans who used to inhabit the area. -Joe Thank you Joe. That info is very informative at a number of levels. I’m not a bivalve person, but I can appreciate the beauty of the shell. @Peat Burns Thanks for the info. Very interesting that they are so endangered and protected there. Link to comment Share on other sites More sharing options...
doushantuo Posted March 13, 2018 Share Posted March 13, 2018 Haas(Die Unioniden): some unionids with more unusual shapes for the group: Unionids have great filtering capacity and are heavily monitored because of their inportance in keeping rivers and lakes clean. Hence the protection. Because of their ecological preferences,they are great proxies for the water quaility of the dulcaquicole (lit."freshwater"/("non-marine")environment. I can wholeheartedly recommend this: Link to comment Share on other sites More sharing options...
KimTexan Posted March 13, 2018 Author Share Posted March 13, 2018 Regarding the ones with ridges: I’m not sure where you start counting ridges. Mine have more than 3 ridges. There is a Fiveridge one, the Coosa Fiveridge, Amblema elliottii, which use to be called Amblema plicata perplicata. Below is the most complete one I found. I’d say it is definitely not the plicata, but it most likely is of the same genus. I think I could have more than one species of them, but for all I know the differences I see could be attributed to dimorphism or juvenile vs adult specimens. I know nothing about Pelecypoda ID. (I can’t remember if the class is italicized. My taxonomy class was close to 30 yrs ago). I’m trying to learn about the ID of most all of the fossils I find (some of which may be modern). I started making the attempt last Fall, 2017. It is slow going, but I am making a sincere effort to learn. I’ve got a biology and clinical medicine background, which helps a little, but I have a long way to go. I truly appreciate your insight and invite any tutorial and educational comments, guidance and direction you may have to offer. This is the Pelecypoda fauna list I have from the “Fossil Collector’s Guidebook to the North Sulfur River” from the “Occassionsl Papers of the Dallas Paleontological Society, Vol. 4.” Maybe some of you who are familiar with the names listed may be able to associate them with the 2 clams in question, if they are fossils. If they’re not fossils then they definitely wouldn’t be in the list. However not being in the list doesn’t automatically exclude them from being fossils either. Link to comment Share on other sites More sharing options...
MeargleSchmeargl Posted March 13, 2018 Share Posted March 13, 2018 I say MAYBE modern, but it's really hard to be certain with some shells, as fossils can look almost identical to recent ones (particularly Mussels). Every single fossil you see is a miracle set in stone, and should be treated as such. Link to comment Share on other sites More sharing options...
Plax Posted March 13, 2018 Share Posted March 13, 2018 2 hours ago, KimTexan said: Maybe some of you who are familiar with the names listed may be able to associate them with the 2 clams in question, if they are fossils. If they’re not fossils then they definitely wouldn’t be in the list. However not being in the list doesn’t automatically exclude them from being fossils either. the list is cretaceous and your clams are Pleistocene or Modern right? Most modern mollusks have representatives that go back at least to the Pleistocene. Link to comment Share on other sites More sharing options...
abyssunder Posted March 14, 2018 Share Posted March 14, 2018 They are too shiny below the external degraded layer(s), in my opinion. " The slow dissolution of these shells releasing calcium carbonate into the water raised the water's pH high enough to prevent the eggshell fragments from dissolving before they could be fossilized. " - Wikipedia " 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...
Coco Posted March 14, 2018 Share Posted March 14, 2018 16 hours ago, KimTexan said: (I can’t remember if the class is italicized. My taxonomy class was close to 30 yrs ago). No, class doesn't need italicized, only genus and species need Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
fifbrindacier Posted March 14, 2018 Share Posted March 14, 2018 I agree with @abyssunder. "On ne voit bien que par le coeur, l'essentiel est invisible pour les yeux." (Antoine de Saint-Exupéry) "We only well see with the heart, the essential is invisible for the eyes." In memory of Doren Link to comment Share on other sites More sharing options...
Plax Posted March 14, 2018 Share Posted March 14, 2018 9 hours ago, abyssunder said: They are too shiny below the external degraded layer(s), in my opinion. " The slow dissolution of these shells releasing calcium carbonate into the water raised the water's pH high enough to prevent the eggshell fragments from dissolving before they could be fossilized. " - Wikipedia I don't understand what this is in reference to? Perhaps I didn't read back far enough. Link to comment Share on other sites More sharing options...
Peat Burns Posted March 14, 2018 Share Posted March 14, 2018 1 hour ago, Plax said: I don't understand what this is in reference to? Perhaps I didn't read back far enough. I had same question. I wonder if this relates to the theory that the presence of mollusks is thought to be a factor in buffering deposits with dinosaur eggs, helping to prevent them from dissolving and thus contributing to their preservation. Interesting, but wondering how it relates to the thread. Link to comment Share on other sites More sharing options...
Plax Posted March 14, 2018 Share Posted March 14, 2018 They made mother of pearl buttons out of fresh water clams (or mussels if you prefer) for a few centuries. The keratinous outer layer was buffed or ground off before the buttons were cut. To me Kim's shells look like old and perhaps Pleistocene examples with the outer layer decomposed baring the nacreous shell within. Link to comment Share on other sites More sharing options...
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