Is Pinguicula macroceras subsp. nortensis valid?

[ICPS-bob]

Is Pinguicula macroceras subsp. nortensis a valid subspecies? Barry Rice presents field measurements:

How much do the flowers of Pinguicula vary in size from site to site? To explore this and related questions, flowers of Pinguicula macroceras from different Californian colonies were studied. It was found that different colonies, even if separated by only small distances, can have significantly different typical flower sizes. These differences are even greater than the differences that were used to define subspecies within Pinguicula macroceras. As such, there is inadequate evidence to support subspecific divisions within P. macroceras.
. . .
Therefore, I conclude that Pinguicula macroceras subsp. nortensis should no longer be recognized as a significant entity, and should be reduced to synonymy of Pinguicula macroceras.

www.carnivorousplants.org/cpn/articles/CPNv40n2p44_49.pdf