![]() Though loosely referred to as "tree ferns", most but not all members of the order possess the characteristic tree fern morphology: the rhizome is massive, woody, and rather than creeping horizontally below or on the ground, it stands erect and above ground, like a tree trunk, bearing a crown of fronds. While the Cyatheales have been shown to be monophyletic through molecular analysis, no prominent morphological characteristics are common to the entire group. It is unclear how many times the tree form has evolved and been lost in the order. However, most plants in the Cyatheales are tree ferns and have trunk-like stems up to 10 metres (33 ft) tall. Some species have scales on the stems and leaves, while others have hairs. Some species in the Cyatheales have tree-like growth forms from a vertical rhizome, others have shorter or horizontal expanding rhizomes. No clear morphological features characterize all of the Cyatheales, but DNA sequence data indicate the order is monophyletic. ![]() The order Cyatheales, which includes most tree ferns, is a taxonomic order of the fern class, Polypodiopsida. Note: These families are alternatively treated as subfamilies of the single family Cyatheaceae ![]()
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