Hi Greg,
Ok, I am not sure if you have seen that there are actually
three categories. I pretty much swiped the categories from the bromeliad society cultivar registration site, though I am myself a little confused by the difference between a sport cultivar and species cultivar. The Hybrid Cultivar is the one I used to do the Agave 'Royal Spine" application. It asks the "If Hybrid" and If not Hybrid" question to document the fact that the parent's of the new hybrid could be hybrids themselves. I think this might be part of what is confusing you. Let me know.....
For example, I have some hybrid seedlings here of Agave celsii 'Nova' which is potatorum x celsii, crossed with colorata. I also have Agave 'Blue Glow' crossed with colorata,
Let me know if that clears it up or I am not addressing your issue.
Allen