Centaurea sphaerocephala subsp. sphaerocephala

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 : 283

(a) Subsp. sphaerocephala :

Stems 5-15(-5O) cm, simple or sparingly branched. Leaves arachnoid-hairy, mucronate-dentate, sessile; lower lyrate; upper entire, auriculate-semiamplexicaul at base. Involucre (15-)25-30 mm in diameter; appendages with 5—9(— 13) yellow spines. Achenes reddish-brown; pappus white, half as long as achene. Throughout the range of the species.