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PSchleis

Can you identify this oyster?

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PSchleis

 I found several of these on Myrtle Beach. I think they’re my favorite oyster fossil. But I’ve checked a bunch of online databases and can’t figure out the name of it.  It’s gold in color.  I should’ve put a measuring tape next to it. They range from 4 to 5 inches long .

 

Thanks!

paula480D66C8-4913-4AA1-94D1-BAA944C11D0B.thumb.jpeg.c4af8aa43bdf269955bcd253518283f4.jpeg7B8E73DB-E9AC-42B0-BD29-0FA9C6D4D211.thumb.jpeg.6af91aaa3f5762f69297c32a6963ce43.jpeg

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Al Dente

These will be difficult to identify, the outer layers are gone.

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Tidgy's Dad

The bottom one of the three in the first photo looks a bit like Exogyra costata, so maybe they all are.

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PSchleis
31 minutes ago, Tidgy's Dad said:

The bottom one of the three in the first photo looks a bit like Exogyra costata, so maybe they all are.

I uploaded some Exogyra costata (linking here) also found on Myrtle Beach and I don’t think these resemble those. These have a dome shape  and the layers dont swirl and connect to a common point.  I’m not an expert so I may not be describing that expertly, but hopefully you get the idea! 

 

 

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Herb

looks like the smaller lower shell of either Exogyra sp. or Pycnodont sp

Pyncodont 1.JPG

Pyncodont 2.JPG

Exogyra costa.JPG

Exogyra costa1.JPG

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abyssunder

The first two, on the left side in the first picture, look like oyster upper valves. Can we have pictures of them showing their opposite side?

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PSchleis
1 hour ago, abyssunder said:

The first two, on the left side in the first picture, look like oyster upper valves. Can we have pictures of them showing their opposite side?

Here's a photo of the underside, and another photo of the top with me holding it - an angle that might better show the large dome.

P1120047.thumb.JPG.60da1fc641bd4a5db66d2365929751c6.JPGP1120051.thumb.JPG.c1dbeb342623195f153fd3ae0fcbbdb4.JPGP1120045.thumb.JPG.3318da34512161ff9fc9437ff31a9803.JPG

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PSchleis
5 hours ago, erose said:

If these are coming up from the Cretaceous deposits there is a possibility that these are worn specimens of Pycnodonte mutabilis. Along with Exogyra it was my experience that those were the larger oysters in the east coast fauna.  Look to see if the muscle scars match either Exogyra or Pycnodonte.

I found a web photo of the pycnodonte that is probably the closest thing I've found to what I have, so I suppose it could be that. The domed tops of the ones I have are fairly smooth, and the online photo is close to the gold color I have. Thanks for weighing in!

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DPS Ammonite
20 minutes ago, PSchleis said:

Here's a photo of the underside, and another photo of the top with me holding it - an angle that might better show the large dome.

P1120047.thumb.JPG.60da1fc641bd4a5db66d2365929751c6.JPGP1120051.thumb.JPG.c1dbeb342623195f153fd3ae0fcbbdb4.JPGP1120045.thumb.JPG.3318da34512161ff9fc9437ff31a9803.JPG

I agree with @Tidgy's Dad, they are likely Exogyra costa. They are very thick and the less worn areas have a corrugated pattern similar to that of Exogyra costa. 

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erose

Despite being worn down to the nubbin I would also offer my SWAG for Exogyra sp., but no more than genus unless E.costata is the only species known from the local.

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Plax

only E. costata here.

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PSchleis
3 hours ago, Plax said:

only E. costata here.

I've never tried collecting fossilized oysters before, so I have zero experience with this. Thanks so much, everyone, for your patience, but I need more help understanding this. Here is a photo that shows two shells on top that have been identified here on a different ID request thread as E. costata, and the two on the bottom are the subject of this current thread and are now being identified as E. costata. To my eyes, they have no similar features whatsoever. The top two are flat, show layers of growth, are dull gray. The bottom two are domes and three times as thick, very gold, and shiny. So what am I missing here. Are these different parts of the shell or something? Thanks!

 

IMG_6674.JPG.1c19b326613e9227206e27c8e7abe1a9.JPG

 

 

 

 

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erose
44 minutes ago, PSchleis said:

I've never tried collecting fossilized oysters before, so I have zero experience with this. Thanks so much, everyone, for your patience, but I need more help understanding this. Here is a photo that shows two shells on top that have been identified here on a different ID request thread as E. costata, and the two on the bottom are the subject of this current thread and are now being identified as E. costata. To my eyes, they have no similar features whatsoever. The top two are flat, show layers of growth, are dull gray. The bottom two are domes and three times as thick, very gold, and shiny. So what am I missing here. Are these different parts of the shell or something? Thanks!

 

 

 

 

 

 

You are looking at an oyster whose two valves(shells) were not symetrical. In bivalves the two sides are described as left and right, but for oysters like Exogyra most of us say top and bottom.  The ones with the distinct spiral ridges are the top valves and are simple flat caps to what was the much more massive bottom/lower valve. The two in this post that we have identified as Exogyra are extremely worn specimens of the lower valve.  But they are, in all honesty, pretty (s)crappy specimens.

 

Look at as many pictures of Exogyra as you can and you will start to see what we mean. AND keep looking at this local and eventually you will probably snag some less scrappy, if not perfect, specimens.  

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Tidgy's Dad

Yes, you get good quality specimens and then those that are eroded, poorly preserved or internal molds. 

Still, I'm glad i seem to have nailed it right from the start. :)

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abyssunder

The upper two are opercular valves, the lower ones are eroded/weathered lower valves of Exogyra, don't know which one of the species. I'm leaning toward E. ponderosa, but I could be very wrong, being not familiar with them of your region.

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PSchleis
4 hours ago, erose said:

You are looking at an oyster whose two valves(shells) were not symetrical. In bivalves the two sides are described as left and right, but for oysters like Exogyra most of us say top and bottom.  The ones with the distinct spiral ridges are the top valves and are simple flat caps to what was the much more massive bottom/lower valve. The two in this post that we have identified as Exogyra are extremely worn specimens of the lower valve.  But they are, in all honesty, pretty (s)crappy specimens.

 

Look at as many pictures of Exogyra as you can and you will start to see what we mean. AND keep looking at this local and eventually you will probably snag some less scrappy, if not perfect, specimens.  

Thank you! I understand now. I didn't realize these are practically fragments of the real deal. 

But I love them just the same. Guess it takes a newbie to appreciate the beauty in a scrappy specimen, haha.

Thanks erose and everyone. These lessons are invaluable to me :)

 

Paula

 

 

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PSchleis
On ‎1‎/‎30‎/‎2019 at 2:07 PM, Herb said:

looks like the smaller lower shell of either Exogyra sp. or Pycnodont sp

Pyncodont 1.JPG

Pyncodont 2.JPG

Exogyra costa.JPG

Exogyra costa1.JPG

Thanks for these photos, Herb. I'm starting to see!

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Plax

The flat shells are the uppers and the deep dish valves were in the mud. The oyster opened the flat valve to filter feed. The costae (ribs) are worn off your lowers but only Exogyra costata is found at Myrtle Beach. Wish I could remember the name of the restaurant where complete well preserved specimens can be collected. It's on the ICW there.

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PSchleis
11 hours ago, Plax said:

The flat shells are the uppers and the deep dish valves were in the mud. The oyster opened the flat valve to filter feed. The costae (ribs) are worn off your lowers but only Exogyra costata is found at Myrtle Beach. Wish I could remember the name of the restaurant where complete well preserved specimens can be collected. It's on the ICW there.

 Thanks Plax.  That’s extremely helpful and interesting!

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