White Faced Capuchin Monkey, Drake Bay, Costa Rica
At least it appears that this white-faced capuchin monkey is having a bit of a rough day. He/she was actually in the process of being groomed by a friend and was, in all likelihood, quite pleased with the afternoon. These two were part of a much larger troop of monkeys that were winding down the day in an enormous oceanfront tree in Drake Bay, Costa Rica.
Nikon D800 with Nikkor 200-400mm lens (at 400mm) ISO 1600, f/4 at 1/250th of a second