I just got back from a work trip to Camp Ripley in central Minnesota. I took the opportunity to visit some local wild areas there after work. There is a SNA site called The Ripley Esker. I was mainly chasing butterflies, but I found some of the flies there to be fascinating. There was a particularly large species of robber fly there that was quite common. My guess is that it belongs to the genus Promachus, a group that is generally called “bee killers.”
I found a large female depositing its eggs on the developing seed head of a wild bergamot. I took a number of photos, first with only natural light, then with a fill flash. The photos with the fill flash showed more of the fine details–the hairs and the claws on the feet of the fly.
But the natural-light only shots showed the lovely green eyes.
This is a large and magnificently beautiful fly.