I think gardneri is synonymous with praestans and glanduliferum....I believe that wilhelminiae is regarded as a valid, separate species. Interestingly, this plant is smaller than many of the wilhelminiae's I've seen...and they are supposed to be the small ones. I'll know when it opens, but I belive a major difference is that gardneri/praestans/glanduliferum is yellowish in background, while wil. is whitish. So far, these buds look yellowish to me. I'll post a pic when the buds open. The spikes are already way taller than when that pic was taken 2 weeks ago. Take care, Eric