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Sword Fern
Nephrolepis cordifolia
ใฟใใทใ
A fern native to the Ryukyu Islands and southern Kyushu, widely cultivated as an ornamental houseplant in warm regions. It produces numerous elegant, elongated arching fronds. The Japanese name refers to the spherical tubers ('tama' = ball) formed on its rhizomes.
Identification Points
- โElongated arching fronds with densely arranged pinnae
- โSpherical tubers (containing starch) on the rhizome
- โSori covered by kidney-shaped indusia
Habitat
Forest edges and rocks of the Ryukyu Islands; indoors as a houseplant
Season
Year-round (evergreen)
Morphological TraitsAI-estimated, needs verification
Evergreen/Deciduous
Evergreen
Leaf shape
Linear
Phylogenetic Positionใฟใใทใ็ง โ
Phylogenetic Position
Vascular plants > Polypodiophyta > Polypodiopsida > Polypodiales > Oleandraceae
Divergence Era
Cretaceous to Paleogene (ca. 70 million years agoโ)
Evolution Notes
Oleandraceae evolved a strategy of rapid proliferation via stolons and tubers. Introduced worldwide as an ornamental plant, it has become an invasive species disrupting native ecosystems in some regions.
View on evolution timeline โSources & References
AI-generated, needs verification