myelaphus's Identifications

This large robber fly -- about 1" long -- posed for me in the black-eyed Susan patch at the Lakeside Commons Educational Gardens. It flew up and briefly tussled with another fly of the same type, and then went back to exploring the flowerbed once its rival had gone. These are common in this area, and I frequently see them resting on flowers. I suspect the hunting is good when bait is available.