Publication: Gen. Fil. plate 67. 1834.
selected vouchers: WTU
Notes: FNA2: "The taxonomy of Dryopteris filix-mas is not well understood. In North America, this fern has been considered both an auto- and an allopolyploid and may be composed of at least two closely related taxa. Plants in the northeast and northwest are tetraploid. These differ morphologically and ecologically from a taxon of unknown chromosome number in the southwestern Rocky Mountains. The Rocky Mountain taxon closely resembles the Mexican D . pseudofilix-mas (Fée) Rothmaler. Dryopteris filix-mas also occurs in Europe, and it is known to be an allopolyploid of D . caucasica (A. Braun) Fraser-Jenkins & Corley × oreades Fomin."