So that's the difference!!!!! the lip size hehehehehe....I always called all this group of "true" coeruleas among purpuraqtas as roxo-violetas just because I didn't find any difference between aço's and shusterianas and every explanations I was able to find was contradictory and very very very subjective if someone know (has I know) examples outside photos... In terms of color, the only difference I find between this group of coeruleas is the hue or in other words the deepness of the blue... but that is a individual difference easy to find in any group of coeruleas on any laeliinae, even between siblings.
I find more "differences" between "Ardosias" than within "roxo-violetas" even if all ardosias on cultivation are descendants of just 2 wild plants (at least outside Brazil because inside Brazil If I recall well there is another clone involved in some plants, but I'm not sure about that), Ardosias at least they vary not only in terms of hue, but in the nature of the color....on one side of the "ardosia" spectrum they are the more real indigo violet-blue, wile in the other side of the spectrum they are the more real grey colored that correlate more with the word "Ardosia"(Slate).
It's quite amazing how colors behave inside brazilian laelias but specially inside purpurata, in fact at least they have two different mutations that produce deep rich colored coeruleas, and one of those mutations the "Ardosias",is amazing how they produce those differences considering that the same gene is the responsible for both sides of the spectrum.
In one parragraf Mauro... If someone like to have at least one color representative of coerulea possibilities inside purpurata, the grower needs at least 3 plants.
At last... thanks a lot for your beautiful "shusteriana"


P.D. I don't use werkhauseri here because is more clonal name than variety name even if outside Brazil "ardosia" is not well known as "variety" name and all ardosias are called werkhauseri... but knowing that many users here are from Brazil, them I keep Ardosia to be better understood that I am not talking about werkhauseri 1 or werkhauseri 2, but in behalf of all 3 or 4 originally wild collected Ardosias from Torres municipality and all its descendants on cultivation.