In the last couple of weeks I have disturbed a number of black "butterflies/moths when walking amongst long grass in my garden. Having done some checks on line I think I have identified it as the Chimney Sweeper moth. I have never seen these before, have no idea what the caterpillar looks like.
My garden is on the edge of approx. 100 acres of rough shrubland which it likes. It is supposed be common but I have certainly never seen one, let alone several before. They are most active in warm sunny weather so the heat wave is probably responsible for its appearance in my garden.