Clam without a foot

[rbatch]

Last week I purchased a 3"Golden Tear Drop Maxima from a very reputable lfs. It appeared very healthy and would close quickly when I passed my hand over it. I placed it on the sand bed in my 150g mixed reef and the next day, I noticed that the clams foot was laying next to it, several threads had latched onto a piece of live rock. It was just swaying in the current. The clam seems unharmed and looks beautiful. Anyone have any ideas as to what happened? Should I be concerned? There is nothing in the tank that could have affected the clam.

 

[skinz78]

This is fairly normal, over time they build up a mass of threads and every once and a while they drop them and start new. Can you post a pic of the clam just to be sure?