This big bee was in our backyard resting on a leaf. One of my sons said that its eyes look like thin plums, the other said that they look like black almonds. Sounded like a bee so far. As I got closer to it though, I started to notice that it looked a bit strange. It had a bee’s colors, but the face and body looked a little different.
In this closeup, I can see that the antennae really resemble those of a fly. This is a Sacken’s Bee Hunter. It is yet another type of robber fly.
According to Field Guide to Insects and Spiders of North America by Arthur V. Evans, these flies attack honey bees and wasps. They grab them with around the thorax (the segment behind the head) so that they don’t get stung. I would imagine that the bee or wasp probably thinks this hunter is just another one of their own kind until it is too late.