Thanks Mark for your photos and measures, I would say it is N. minor subsp. asturiensis, with particularly long and slender tepals and corona, with a ratio corona/tube= 2.85, somewhat longer than is normally found in N. asturiensis (ratio 0.88-283), and much shorter than it is found in N. cyclamineus (ratio 5.2-18.8), following Flora Iberica. Regarding the filaments, they are shorter than the style both in N. cyclamineus and N. asturiensis.
I would classify it as Narcissus minor subsp. asturiensis in www.biodiversidade.eu. This thread of comments will help to keep the idea that is is not the commonest form, and that some doubt of introgression (i.e. from N. cyclamineus) could still be cast. :-)