Sonchus maritimus subsp. maritimus

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 : 327

(a) Subsp. maritimus :

Involucre c. 15 mm; outer bracts ovate-lanceolate, the inner lanceolate. Achenes oblong. Damp, saline soils. Throughout the range of the species.