Easiest would be to stick with species. And then - any unregistered hybrid is certainly a no go.
So here I looked at the Phragmipedium species page:
http://garden.org/plants/searc...
Now why do some have written Phrags, some have an extra Phragmipedium with species in brackets, Phragmipediun besseae is listed as Peruvian Lady Slipper (not really true).
My question is, why is this not streamlined at the simplest level?
This is only one genus I looked at so far. Sorry, not trying to be difficult.
edited to add - Elaine, you just ran into the same thing I commented on. One really would need to start streamlining and figure out if one really wishes to also add common names, which I would strongly discourage. It is plenty work just to get the latin names correctly, with synonyms. Get the Genus, species or hybrid, perhaps down to specific clonal names, and that's it.