Big shell! Old Shell! Help! Found in Montana

[paul monfils]

Hi Seth,

Yes, this is a "big shell", compared to most other species of shells.  But actually for this species, this specimen is a small one!  This is in fact the largest species of mollusk shell in the world.  The scientific name is "Tridacna gigas", and the common English name is "Giant Clam".  It has been known to reach 4 feet in length, and a weight of more than 500 pounds.  If you scroll down on these two pages, you can see a large one with a person next to it, to provide scale.

http://www.lithiccastinglab.com/gallery-...spage1.htm

http://www.advancedaquarist.com/2010/11/inverts
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