Stilt-legged flies (Rainieria antennaepes) are ichneumonid wasp mimics who walk with their front legs extended, appearing like wasp antennae. I have to admit that this fly did an excellent job of initially fooling me.
The adults feed on detritus and dung. The natural history of this species is poorly understood.
There has been an abundance of these flies around the peony bushes and along the green house siding.