This is called a Chiton These are pretty cool little creatures and a little on the rare side. They are native to the northern atlantic, but manage to ride into homes on live rock. Great camoflauge animals as they can change color. They feed on coraline algae and are of no harm to your aquarium or inhabitants. They can stay out of water for days on end by using their "shells" to conserve the water within them. can be very old depending on size. 50+ years for 1 1/2"-2" Needless to say if u donot want him.. I'll give him a good home. Warning: Dont try to pry off the rock he is attached to!
Cool pics, and I would agree with Camn55ivie on the id. Any other members have any input? Here is a link from Marc Levinson's web site on creature ID's. Hold your mouse cursor over the picture. http://www.melevsreef.com/id/snails.html
