Saturday I ran across an interesting fly as I was photographing insects.
This is a shore fly, apparently in the genus Ochthera. Notice that it has enlarged front legs. It seems that they are able to use them in a manner similar to the legs of a praying mantis–they can grasp and eat prey with them. However, I saw this one doing something different.
It was doing some kind of visual display. I have seen other flies with similar displays–it is quite common in the fruit flies, for example this Euaresta bella.
E. bella waves its wings and dances around, trying to attract other E. bella.
This, too was an obvious visual display. I did try to locate additional individuals that day and the next but with no luck.
I have seen fruit flies doing displays like this and not seen any others nearby. I saw no obvious audience for this one either.