Florida Bee Killer (Mallophora bomboides)
I've been stalking this elusive fly for several months but still have not been able to get close to one. Mallophora are formidable hunters, patrolling their territory in low-flying and surprisingly fast patterns like noisy, fuzzy, mini-helicopters. They mimic bumblebees and capture bees, wasps and other flying insects for food. There is even a documented case of one species capturing and eating a hummingbird. They are in the robber fly family (Asilidae). I got within 5 feet of this one then leaned, stretched out my arms and held my breath for the shot, just before it buzzed away.