Orobanche, Wallr.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 288

Sect. Trionychon Wallr. Stems simple or branched. Flowers pedicellate or sessile, with 2 bracteoles adnate to calyx. Calyx with cylindrical to campanulate tube and 4 subequal teeth, rarely with a fifth, much smaller tooth. Corolla white, cream, blue or violet, constricted below the middle near the insertion of the filaments; upper lip 2-lobed.