Oh! Thanks for taking a closer look, Joshua! I had interpreted the droplet glinting as speckles, which is an unusual trait for a martagon.
Being from the land where Claude Shride originated (about 70 miles southeast of me), I've seen many. Even in my own garden, they can vary with the number of spots, from sparsely spotted to no spots, and even the light midrib color can appear or not appear from year to year. I certainly don't know what they might display in the UK. I have grown several other cultivars/and of questionable identity that look similar. It's a look that comes up fairly commonly in breeding. All this said, I don't really have an opinion either way, if it is Claude Shride or not. Probably the best way to know, barring info from the Harlow Carr garden itself, would be to compare the growth form of the entire plant, rather than rely so much on the flower.
