sphecodes ~ blood bees
The blood bees have nothing to do with blood save for the color of their abdomens. They do have a sinister side if you're a sweat bee or a mining bee, though. As cleptoparasytes, they hunt for the nests of these bees and deliver eggs that will compete for the nest provisions. They are spirited in their work, flying for short bursts and walking frantically along the ground.