worn shells from SC I can't identify

[rhclouser]

These shells were found in North Myrtle Beach SC. They're quite worn, and all have taxodont dentition. I think they're some kind of ark shells, but they all look a little different than the ones I'm sure of. If I number them from top left to lower right,

1 2 3
4 5 6

I think 3 and 6 (and maybe 1) are blood arks, but look a little different from the others I have and am sure of.

But I'm not sure about the others. The beak/umbo are near the center of the hinge line. 1 and 4 might be ponderous arks.

I guess my real problems is with 2 and 5.

Any help from anybody would be greatly appreciated.

Thanks,
Bob

[paul monfils]

These shells were found in North Myrtle Beach SC. They're quite worn, and all have taxodont dentition. I think they're some kind of ark shells, but they all look a little different than the ones I'm sure of. If I number them from top left to lower right,

1 2 3
4 5 6

I think 3 and 6 (and maybe 1) are blood arks, but look a little different from the others I have and am sure of.

But I'm not sure about the others. The beak/umbo are near the center of the hinge line. 1 and 4 might be ponderous arks.

I guess my real problems is with 2 and 5.

Any help from anybody would be greatly appreciated.

Thanks,
Bob

[paul monfils]

Hi Bob,

Yes, these are all Arcidae. I agree on the Noetia (Eonsia) ponderosa (1 and 4) - thick, solid shell and distinctive shape. Also agree on Anadara (Lunarca) ovalis (3 and 6). The almost round shape and rather thin shell are typical. I believe (2 and 5) are Anadara transversa, based on the elongate shape and high rib count (appears to be over 30). Both transversa and ovalis are common on my local beaches here in Rhode Island, but ponderosa doesn't range this far north.

Regards, Paul