It's Peacock Flounder, "an unusual fish that can change colors to hide itself. The faint blue circles on its white body gives this fish excellent camouflage as it hides on white sand. A master of disguise,it has been able to match the pattern of a checkerboard in some laboratory experiments"....e-reefnews

Thanks, Richard! Lovin' the zen.
Have a great night. :)
 

I didn't know exactly what type of flounder it was, thank you. And though I expected that the blue circles were for the sake of camouflage, I wonder why they're more effective than, say, simply matching the color of the sand would be. Anyone?
 

The blue rings are to simulate the illusion of rocks or variations in the sand. I would think that other fish and sea predators lack 20/20 vision so that this works.
 

Works for me. Thanks!
 

Actually, the purpose is to avoid detection by Chris Hansen.
 

The above is correct but there is also the thought that the peacock flounder shows its colors more prominently when it feels threatened.
 

Interesting. That's as close to it as I got, and the flounder didn't move, which they will if you get really close, so I hope it wasn't feeling threatened....