Centaurea nigra, L.

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 : 293

187. C. nigra L. , Sp. Pl. 911 (1753).

Perennial. Stems (15-)3O-100 cm, erect or ascending, simple to corymbosely branched, the branches thickened below the capitula. Leaves green, to greyish-arachnoid-hairy; lower ovate to lanceolate, entire, dentate or lobed; upper entire, lanceolate. Capitula solitary or in clusters at apices of branches. Involucre 12—18 x 15-20 mm, globose; appendages black or blackish-brown, ovate-orbicular to linear-lanceolate, mostly completely covering bracts, the apex somewhat recurved, plumosely pectinate-fimbriate, the fimbriae shorter than or up to 3 times as long as the width of the appendage, 10-20 on each side, dark to pale brown. Florets purple, the outer usually not radiate. Achenes c. 3 mm, compressed; pappus 0.2-4 as long as achene. In = 22, 44. • Europe eastwards to Sweden and C. Italy, one station in C. Jugoslavia. Be Br Ga Ge Hb He Ho Hs It Ju Lu No Su [Au Cz Da].

Variation in this species has been discussed by D. J. Ockendon, S. M. Walters & T. P. Whiffen, Proc. Bot. Soc. Brit. Is. 7: 549-552 (1969).

1 Outer florets somewhat radiate; involucre c. 18 mm in diameter (c) subsp. rivularis

1 Outer florets not radiate; involucre 12-15 mm in diameter

2 Fimbriae dark brown, 15-20 on each side (a) subsp. nigra

2 Fimbriaepale-or yellowish-brown, 14-16 oneachside (b) subsp. carpetana