Erigeron uniflorus, L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 119

14. E. uniflorus L. , Sp. Pl. 864 (1753).

Perennial not more than

15 cm. Basal leaves 2-5 x 0-4-0-9 cm, spathulate, narrowly petiolate, rounded at the apex, ciliate, sparsely pubescent when young. Flowering stems ascending to erect; cauline leaves 2-5(-8). Capitula solitary. Involucral bracts moderately to densely pubescent, lilac distally, sometimes slightly recurved. Florets dimorphic; ligules white or pale lilac. 2« =18. Snowpatches, stony slopes and alpine pastures. Arctic and subarctic Europe and W. Fennoscandia', mountains of C. & S. Europe southwards to the Pyrenees, C. Appennini and S. Carpathians', S.W. Bulgaria. Au Bu Co Cz Fe Ga Ge He Hs Is It Ju No Po Rm Rs (N) SbSu.

Very variable. The plants from Bulgaria (Pirin Planina) have been described as E. vichrenensis Pawl. , Acta Bot. Croat. 28: 287 (1969). They have densely pubescent and purplish involucral bracts and purple ligules. The most distinct regional taxon is E. uniflorus subsp. eriocephalus (J. Vahl) Cronq. , Brittonia 6: 236 (1947). It has densely hairy involucral bracts, with hairs up to 2 mm, the outer bracts being distinctly recurved, and has 2« =18. It occurs here and there with subsp. uniflorus in the mountains of N. Fennoscandia and Iceland and largely replaces it in the Arctic. It is, however, difficult to distinguish it from certain plants from S. and C. Europe.

E. aragonensis Vierh. , Beih. Bot. Centr. 19(2): 518 (1906), from the Pyrenees, which similarly has densely hairy involucral bracts but also narrow basal leaves (up to 0-3 cm wide) and ligules (4-)5-8 mm, is possibly worthy of specific rank. It has 2л=18. Long ligules are also characteristic of plants from Corse.

E. candidus Widder , Ber. Deutsch. Bot. Ges. 50: 77 (1932), described from S.E. Austria (Koralpe), is of uncertain status. It resembles both 12 and 14, which are absent from this area, and is distinguished from both mainly by having larger, wider leaves, more densely pubescent flowering stems, solitary capitula and always white ligules.