Scorzonera purpurea subsp. purpurea

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 : 319

(a) Subsp. purpurea :

Rootstock densely fibrous at apex. Stems 10-70 cm, often branched above. Leaves 0-1-0-3 cm wide, canaliculate, keeled, more or less erect. Involucre 15-25 mm, with 10-16 bracts. Ligules pale lilac. Achenes 10-12 mm, smooth. Dry places. Throughout most of the range of the species but absent from most of the Balkan peninsula.