Synonym: Plenasium banksiifolium.
Clades:
Osmundaceae.
Region: Pacific coast of Asia, Kamchatka Peninsula, Ryukyu Islands, Japan, southeast China, Taiwan, Philippines, Borneo, Sulawesi, Java.
Use: ornamental.
BotanyFern; up to 150 cm tall.
Leaves: 3 types of pinnae: fertile, sterile, and semi-fertile; fertile pinnae are very different from that of the sterile pinnae, curled.
Sporangia can also grow on the vegetative pinnae immediately above and below the fertile pinnae; young opening sterile pinnae are red, the fertile pinnae are mustard yellow at first, later green and finally reddish brown; fertile pinnae can reach more than ten pairs.
TaxonomyPlenasium is recognized in the Pteridophyte
Phylogeny Group classification of 2016. Some sources place all Plenasium species in a more broadly defined Osmunda.