Laphria robber fly and prey

Among the most anticipated arrivals in the summer fly department would be these bumblebee mimics belonging to the dipteran genus Laphria. I've been waiting for these loud and ferocious insects to make their presences known for about a week now—their typical appearance dates are in my phenological calendar—so I was primed and ready when one noisily descended to a Hydrangea blossom filled with long-horned beetles and then quickly departed with a hapless prey item. The laphrid predator—they're hard to identify to species from a photograph alone, and I have no real desire to collect them to make a positive ID (a generic approximation is close enough)—soon landed on a Hydrangea leaf. With the beetle now injected with digestive enzymes and quieted by neurotoxins, the so-called Robber Fly began eating, well, drinking, the remains of its calm and resigned prey.