Last year, I set out bamboo canes as habitat for solitary bees. Several Japanese Hornfaced Bees nested in the canes, which was very exciting and interesting. While setting up to take photos of the bees coming and going, I noticed this tiny fly hovering in front of the cane bee condo. It was very intentional in the way it was hovering and checking out the canes. Sure enough, when one of the bees flew out, the fly scurried into the cane. I had taken a workshop on bee parasites and kleptoparasites and suspect that this fly may be a klepto. I don't know if it shows in the photo, but the abdomen of the fly was striped dark charcoal grey and lighter grey. This spring, when I split the canes to remove and clean the hibernating bee cocoons, I did find several chambers that had some kind of non-bee larvae in them. I don't know if they were larvae from this fly, or some other invader. I'd love to know what this little fly is, specifically, if possible.

I looooooooooove your site. This is the first image I've submitted for ID. I hope y'all can help.

Best wishes,

Jess