Image credit: David Gould
The Common Froghopper, Philaenus spumarius - source of the familiar 'Cuckoo-spit' on plant stems - is a spectacularly variable species, with many dramatically different colour forms.
For every 40 or so Common Froghoppers you might come across a Neophileanus lineatus or two, distinguishable by the pale line running down the outside edge of the forewing, and by the central, anterior 'plate' on the vertex which is wider than long.