Genus of ferns
Plenasium is a genus of ferns in the family Osmundaceae. It is recognized in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), but kept within a more broadly circumscribed genus "Osmunda" by other sources. The genus is known from Early Cretaceous to present.
Taxonomy.
As of October 2019[ [update]], the "Checklist of Ferns and Lycophytes of the World" accepted the following four species:
Phylogeny of "Plenasium"
The following fossil species are also accepted.
References.
 ;templatestyles src="Reflist/styles.css" / ;