Sisymbrium septulatum DC. (syn.: S. erucastroides (Stapf) Bornm., S. grandiflorum Post) (W and C-As., NE-Afr.) – An exceptional and ephemeral alien. Recorded only once on a grain dump in Andrimont in 1954 (as Sisymbrium altissimum), along with numerous other grain aliens from Asia Minor.
Sisymbrium septulatum much resembles S. altissimum but is larger in all its floral parts. It might have been overlooked near grain mills, especially in the past.
Selected literature:
Van Ooststroom S.J. & Reichgelt Th.J. (1958) Floristische notities 35-58. Acta Bot. Neerl. 7: 33-52.
Taxonomic name: