Carduus nutans subsp. nutans

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 : 223

(a) Subsp. nutans :

Leaves 6- to 8-lobed, with strongly raised veins beneath. Capitula 20-40(-50) mm in diameter; involucral bracts 1-5—3(—4) mm wide, with the mid-vein raised in the distal I; outer and middle bracts suberect to deflexed. Throughout the range of the species.