I was wondering how one should handle variegated versions of plants in the database. I have come across a lot of pictures of variegated Agaves listed directly under the species name. I guess in principle this is fine, as it is basically the same species, but in the trade they are definitely considered as separate plants distinct from the non-variegated versions, and there are clear cases where the variegated version of the plant does not look a lot like its non variegated version.
My suggestion would be to create a separate database entry for the variegated versions of the plants and move the pictures with the variegated plants in them to those entries.

Any thoughts?

It would break the architectural rules of our database. We have an entry for each genus, each species, and each cultivar. I don't think we should have extra entries for any other categories.

I think you can argue that variegated plants are in a way cultivars, because their availability in the trade way exceeds their occurrence in nature, they are specifically selected for propagation/cultivation just like an exceptional specimen with a different growth habit or spectacular flower color or size will be chosen for propagation and tissue culture leading to a specific cultivar.

Zuzu, If someone doesn't know the cultivar name, it should go in the parent plant entry, correct? Agaves (Agave)

I tend to agree with mcvansoest, that most variegated plants should be treated as different cultivars. Of course many of them will have names that are specific to that particular cultivar eg. Agave americana var. medio-picta 'Alba'.

Yes, Lin, unidentified cultivars should be added to the generic entry, unless the species is known, in which case they can be added to the species. If they're hybrids, they should be added to the generic entry, of course.

I should amend my previous statement to say that we have an entry for each genus, each species, and each named cultivar. We do not have entries for unnamed cultivars or for unnamed hybrids.