I just got back from a trip with my son on the Turks & Caicos Aggressor II. The ship's captain (Piers) had said that 3 Lion Fish had been seen at various sites. His theory was that some eggs had been inadvertently released from a research station in Florida, and had made their way down through the Carribean. On the last day of diving, I was fortunate enough to find one at a site (The Crack on the North Point of Providenciales) where none had been seen before. He/she was in 50' of water just to the right of a large pillar coral in a sandy patch.
The little guy was hiding in a crevice. And, of course, I had a 10.5 mm fisheye lens with me. Since he was backed into the crevice, I had to swing my strobe around in such a way to back-light him. So, nothing fancy with this shot. Just an "evidence" photo!