Finally, something has shown up next to the pond. Or puddle. I’m not expecting whales or dolphins or anything amazing, but I’d expected some insects to show up. It’s a nice little pool. Surrounded by nettles.
I think this is Helophilus pendulus, a hoverfly. According to Wikipedia the scientific name means “dangling marsh-lover” – which seems a pretty accurate description.
[Later … Perhaps it’s Myatropa florea (batman hoverfly) – I can’t tell]