Could it be a Leaf Cutter bee?
I've had them coming in the green house the last few years looking for a spot to lay their eggs, they get a bit grumpy when I'm in there too and buzz me a bit, but I don't think nasty stingy things. My peppers had a similar appearance, though luckily they tend to do most of their cutting outside and then bring a bit of leaf in. They love compost filled pots!.