Onocleaceae
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Sensitive Fern family
Onocleaceae
コウヤワラビ科
A small fern family including Onoclea, Matteuccia (ostrich fern / kogomi), and Pentarhizidium. Notable for pronounced frond dimorphism: fertile fronds bear bead-like, tightly rolled pinnae. Distributed in temperate regions of the Northern Hemisphere.
Key Characteristics
- ●Pronounced dimorphism between sterile and fertile fronds
- ●Fertile fronds with bead-like, tightly rolled pinnae
- ●Sterile fronds large, pinnately compound
- ●Grows in moist forest floors and near water
Phylogenetic Position
Vascular plants > Ferns > Polypodiales > Onocleaceae
Divergence Era
Cretaceous (approx. 100 million years ago onward)
Representative Genera
コウヤワラビ属（Onoclea）クサソテツ属（Matteuccia）
Related Evolution Events
- ・Distinctive evolution of frond dimorphism for spore dispersal