Unidentified Clam From Liverpool N.S, Canada

[bekkievandenberg]

I found a ton of clam shells at Summerville Beach in Liverpool Nova Scotia .
Can someone please help me to identify them ,
I don't think they are "Soft Shelled Clams" because .. they don't have a brittle shell .
This one in the picture is about an inch and a half long .
Thanks !
(Sorry, it's a huge picture)

<img src="http://i224.photobucket.com/albums/dd78/xxx_bekkie/100_3407.jpg" alt="http://i224.photobucket.com/albums/dd78/xxx_bekkie/100_3407.jpg" style="border:0" />  <span class="petit">--Last edited by bekkievandenberg on 2010-08-05 18:32:01 --</span>

[paul monfils]

This appears to be a wave-polished (in life it isn't this glossy) Mesodesma arctata, sometimes called "Arctic wedge clam".  In life it also has a thin brownish periostracum covering the shell. I have found these in quantity on the beach at a couple of locations in New Hampshire and Maine.  <span class="petit">--Last edited by Paul Monfils on 2010-08-05 19:50:27 --</span>

[bekkievandenberg]

Thank you so much !
It's been driving me crazy .
Most of these shells I have found have been extremely shiny .
And they've had holes in them .
Small, perfect circles, usually on the place where they'd be connected to the other side .
Do you know what those holes would be from ?

[paul monfils]

Many of the ones I found also had such holes.  They are caused by moon snails of the family Naticidae, which feed largely on bivalve molluscs, and use their radula to rasp a hole in the shell of the prey.  Most likely predator in this case would be Polinices (Lunatia) heros.

[bekkievandenberg]

ahhh, that would definately explain it then !
i've found atlantic surf clams with such holes and where i found most of them, that area has millions of moon snails .
thats really neat, i'm glad i know that now
moon snails are my favourite, every time i go beachcombing, i hope i find one !