Using cultivar names for former species (eg. undulata) or even for hybrids of recognized species can be problematic unless there is essentially no variation. A cultivar name should represent one plant, that is to say one genotype, one phenotype, at least until its variegated sports (or whatever) arrive on the scene. Once a cultivar name starts being applied to a range of forms then its meaning is lost, or at best diluted.
That said, I realize the database is full of 'Cultivars' that do not conform to this rigid thinking, and may themselves vary quite a bit (for example the generic 'Variegata' which applies to however many individual variegated forms). I do try to weigh the advantages of specificity (an imperfect name may be better than no name). But in this case I really have no idea how extensive or variable the former species undulata may be, and whether it may include plants visually different from the wavy leafed plant that originally went out through the ISI (which the database has as 'Mucronata').
As a side note, using Latin names for cultivars is also problematic if not impermissible, in a strict botanical sense. It breaks down the firewall we keep linguistically between single plant forms (Aeonium 'Zwartkop' or 'Sunburst' for example) and whatever range of forms may constitute a species (or former species), whose name is typically Latin. I'm not advocating any particular change to the database, just noting the imperfections in cultivar naming.
