round ish holes about 8mm across and sometimes joining up in the dock leaves are a hint they were or are there
bright iridescent green beetles, basic shape is plump in 3 directions, size is variable, males are smaller than the women, most are under 8mm but there are a few giant beasty ones in most colonies that get upto to a cm longways
No, pretty sure I have never seen them. They do sound pretty though.
We get some sort of oil beetle a lot in the 'yard' in the woods and the badgers dig in the sawdust pile for grubs of some sort. There also seem to a lot of bitey things; some are gnats, but others are quite small but still bite.