This very active wasp was hunting its hosts in my back yard. It was hyperkinetic, but I did get a few shots as it paused with a paralyzed spider. An expert on BugGuide identified it as
Phanagenia bombycina. Length perhaps 12-15 mm.Creepy note. Looking at other comments on this species on BugGuide, I just noticed that the wasp has amputated most of the spider's legs after paralyzing it. Appears to be standard practice for this wasp. (I may have caught it here about to amputate that last leg, actually.)