Asperula 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 : 14

(a) Subsp. purpurea :

Stems (15-)2O-5O(-6O) cm, with curved hairs. Leaves 10-20 x 0-4-1 mm, in whorls of (6—)7—10(—11), narrowly linear to filiform, gradually acuminate; margin distinctly revolute. Inflorescence-branches patent and curved; bracts lanceolate, long-acuminate. Corolla usually purple, sometimes yellowish; lobes distinctly apiculate, almost always glabrous. 2zz = 22. Throughout the range of the species except S. W. part of Balkan peninsula.