It’s quite the transformation, from this green larva that looks a bit like a cross between a slug and a caterpillar …

to this black-and-white flying creature.

This is the hoverfly Scaeva pyrastri and, amazingly, it’s a migrant from mainland Europe. A bit like the Red admiral butterfly, Scaeva pyrastri has good years and bad years, sometimes visiting lowland Britain in large numbers, sometimes hardly at all. And, when it comes here, it does often breed locally (and here, I must add a caveat – the larva in my first image may actually be the other Scaeva species, S. selentica, though that species hasn’t actually been recorded in my area).