Yikes, given their (S. greggii & S. microphylla) propensity to interbreed in both the wild and in cultivation, I imagine that it would be extremely difficult (impossible?) to sort out which were decedents of the plants actually collected in Jame and which weren't. If you restricted "× jamensis" use to only the plants collected in the wild by Compton and Yucca Do in Jame ('Sierra de San Antonio', 'Pat Vlasto', etc) then that might be doable. However, what do you use as an epithet for the man-made or cultivated versions of the same cross? Using "greggii" is even more inappropriate and including no epithet at all would be incredibly confusing. Salvia greggii × microphylla (or reverse, if known) would be appropriate but I didn't think that was an option in our database.
The horticultural societies, industry, botanical gardens, etc. commonly use "× jamensis" for both wild and cultivated versions. Unfortunately, some companies call everything "greggii" even when plants are clearly hybrids or even pure S. microphylla.
I'm not sure if there is an easy solution for this particular issue.
(Edit, after seeing your edit
... Yes, I'm aware that is technically correct. I'm just not sure how they can be listed here without making an even more egregious taxonomic/nomenclature error, or creating total confusion.
)
Yes, greggii is absolutely wrong in these cases. What we do in cases of hybrid plants is list only the genus and then show the parentage in the parentage field of the entry. We also list some names in the also-sold-as field when the epithet is incorrect but is commonly used.
