That's not really a stinger, it's just his proboscis, used for sipping nectar. This is a Bee Fly, taxonomic family Bombyliidae, and they live on pollen and nectar. You'll often see them hovering in place over a flower.

I caught this guy in flight with a Canon 1DX, high speed burst mode, Canon 100mm 2.8L IS macro lens, 1/1250th, f/5.0, ISO 2000.