Examples of Striped Lychnis caterpillars feeding on Dark Mullein.
No interactions present.
I assume its named Striped Lychnis after Verbascum lychnitis (White mullein) not Ragged-Robin.
That is Maitland Emmet's derivation. (The Scientific Names of the British Lepidoptera - their history and meaning)
Lat/Lng: 51.5, -0.9
OS grid ref: SU7785