Centaurea seridis subsp. seridis

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. seridis :

Lower leaves oblong-ovate in outline, sinuately lobed; upper oblong-lanceolate, pinnately lobed, the segments spinulose-mucronate. Involucre 20-25 mm in diameter, subglobose; appendages with stout apical spines, the central spine longer than the others. Dry, open habitats. S. Spain.