What is this?

[High tide]

Originally Posted by Treebeard

I am not sure where the rock is from, but I think you are correct. It looks like this one:

http://www.poppe-images.com/images/i...p?picid=905862

Thanks for your expertise!

That looks pretty close,eh!? I have one in my tank, it came on some Brazil rock. It's been there for about 3 years or so, it dwells in a cave created by encrusting and plating corals and doesn't harm a thing(that I care about anyway), it's about the size of a toonie now. You're welcome, anytime!