Sluggin' Along: Efferia Robber Fly

I recently happened upon a large flying insect perched on a branch. As I had never seen such a fly before, I did some research and learned that it belongs to the family Asilidae: Robber Flies. I can't say I'm confident of my ID, but I believe it's a member of the subfamily Asilinae, genus Efferia. Within that genus are several groups. I think the Nerax group is the best fit, with Efferia aestuans being the likely species. The long ovipositor indicates it's a female. Note the black, short, stout mouthpart designed for piercing prey, injecting toxin, and sucking out the fluid. Also note the tapered, banded abdomen and the black central stripe on the dorsal thorax, with two small black patches on either side.