This is Proctacanthella cacopiliga. It is in the Asilinae subfamily with Proctacanthus and the Efferia. Looks kind of like a rufus-colored miniature Proctacanthus with an unusual bulby tail in this male. These were at Holla Bend and they were flying up and down the grassy pathways near an open cow grazing area. I have not found them elsewhere but they are known from several counties now. Fairly widespread eastern species. The other five members of the genus are all western and Texan.

This is the female. Note how bright reddish black that terminus is. With a very white face.