Here's another macro photo from way back that I dug up and cleaned up on a rainy afternoon in Palau, the same day I processed the red-margin shrimp goby photo I posted a couple of days ago.
This is a juvenile pale razorfish (Iniistius aneitensis) with its mouth open. I photographed it in early 2009 while I was visiting the Lembeh Strait.
If you've ever seen one of these, you'll know how haphazard and unpredictable their swimming can be. As I recall, getting the fish to be comfortable enough to pose for a side-on portrait with its mouth open took a lot of time (and grumbling).