Carduus helenioides Linnaeus, Species Plantarum 2: 825. 1753.

"Habitat in Anglia, Sibiria." RCN: 5969.

Lectotype (Airy Shaw in Repert. Spec. Nov. Regni Veg. 43: 306. 1938): Herb. Linn. No. 966.36 (LINN) .

Current name: Cirsium x helenioides (L.) Hill ( Asteraceae).

Note: Although Cirsium x helenioides (L.) Hill and C. heterophyllum (L.) Hill had been treated as synonymous by many authors, study of the type of C. × helenioides (966.36 LINN) by Talavera & Valdés (in Lagascalia 5: 155-157. 1976) has shown it to be a hybrid between C. heterophyllum and C. rivulare (Jacq.) All. As C. x helenioides and C. heterophyllum are therefore not synonymous, C. × helenioides becomes the correct name for the original taxon.