A genus of ca. 4 species, if circumscribed (as here) to exclude Todea, Leptopteris, Osmundastrum, Plenasium, and Claytosmunda, following PPG I (2016) and (in part) Metzgar et al. (2008).
ID notes:An obligate wetland species, Osmunda spectabilis looks less like Claytosmunda claytoniana and Osmundastrum cinnamomeum than they look like one another, with larger and more widely spaced (diffuse) ultimate leaf segments
Ref: Arana & Ponce (2015); Kramer & Green (1990); Lellinger (1985); Metzgar et al. (2008); PPG I (2016); Tsutsumi et al. (2011); Tsutsumi et al. (2021); Whetstone & Atkinson (1993) In Flora of North America Editorial Committee (1993b); Yatabe, Nishida, and Murakami (1999); Zhang, Iwatsuki, & Kadokawa in FoC (2013). Show full citations.