At least I think that is what these remarkable looking little fish are. They may also be very very juvenile spotted drum but I'm going with high hats.
Its amazing what you can find in the shelter of small boulders if you look closely enough. I've not seen any members of this family schooling before so this was a treat. No scale object but each fish is around an inch and up close they were basically transparent.
These guys are constantly moving so I couldn't pick out an individual for more detail, hopefully at least one of the school is in focus somewhere there though.