Oh dear!! Here's the old bag of worms, and they are still wriggling eh?
I have only seen this species in Puebla, south of the city, and around Tehuacan, a good distance from where Amante found this form. My view, based on the degree of variability I saw in this area, both at the same location,and at different locations, is that this is such a variable species that to divide it into subspecies has no real validity. I'd expect that it would continue to be variable in other parts of its geographic extent.
Reppenhagen uses elegans as a species name to include dealbata and san-angelensis; Hunt used haageana ssp. elegans to include collina, but now (New Cactus Lexicon) scraps all previous subspecies in favour of a single highly distributed and variable species under haageana.
So, I don't really think you are going to get a satisfactory outcome on this.

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Chris43, moderator