Osmunda

Kessler, Michael & Smith, Alan R., 2017, Prodromus of a fern flora for Bolivia. IX. Osmundaceae, Phytotaxa 327 (1), pp. 100-102 : 100-101

Osmunda L., Sp. Pl. 2: 1063. 1753.

This genus is characterized by hemidimorphic, bipinnate leaves with fertile pinnae positioned apically, or dimorphic, bipinnate leaves. Until recently, this was regarded to be a genus of about eight species consisting of three distinct subgenera ( Yatabe et al. 2005, Metzgar et al. 2008, Tsutsumi et al. 2011), but more recently the three genera have been considered to better be treated as genera, with Osmunda in the strict sense having 3 species, Plenasium C.Presl with four, and Claytosmunda

(Y.Yatabe, N.Murak. & K.Iwats.) Metzgar & Rouhan (PPG I 2016: 31), with a single species. Osmunda has a long fossil record ( Phipps et al. 1998).