Stag beetles dont fly-do they?-are they around now?
Stag beetles are big.
how big are these beetles? where do you see them ? (ground, plants, compost heap?) are there lots of them or the occasional one
Wouldn't be green shield bugs??-though the description.....
I'll have a think, not sounding familiar at the moment. When they turn up you may have to take a pic.
Look up fur beetles which are native and Asian long horned beetles which are a pest and look quite spidery.
Forget the green shield bug-forgot they were black-is this it?