Chris,
according to Zonneveld, this is simply N. romieuxi ssp albidus. As the species may well represent an ancient allotetraploid hybrid of N. bulbocodium x N. cantabricus, the variations often noted as varieties and subspecies would be expected. To my eyes, the few plants I've seen of romieuxii are all very similar and do not merit seperation, but, then, I am more a lumper than splitter.