Onopordum acaulon subsp. acaulon

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 : 245

(a) Subsp. acaulon :

Leaves more than 3 times as long as capitula, pinnatisect, with 4-6 pairs of distant, broadly triangular lobes; lobes with 2-3 pairs of palmately arranged rigid, yellowish spines. Capitula 40-60 x 50-70 mm, globose-campanulate; involucral bracts curved or patent in distal half. 600-1300 m. Throughout the range of the species except E. Spain.