Confidence: It's likely to be this, but I can't be certain.
Notes: Caterpillar 19mm long found hanging on a silk thread from blackthorn. It is a good likeness for the images in ukleps, closer to the 9mm larva offered than the 20mm one. Ive checked the other Thorn moths and it fits this one best by a long way. It is anatomically accurate though the colouration of this is slightly different ot the 9mm larva in ukleps. This one has fewer pale markings.