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Tietea
''Tietea'' was a genus of Marattiales, marattialean tree ferns from the Late Carboniferous to the Permian. The genus has been placed in a number of families, including Psaroniaceae. The first described species was ''Tietea singularis'', which grew up to in height. It is estimated to represent close to 90% of some fossil assemblages in Brazil. ''Tietea derbyi'' was described in 1992, but its validity has been questioned as it could be a laterally flattened specimen of ''T. singularis''. Description ''Tietea singularis'' stems usually are less than in diameter, bearing four orthostichies of leaves in a decussate arrangement. The stem is surrounded by a continuous ring of sclerenchyma that separates it from the root mantle. ''T. singularis'' stem transverse sections have the same basic structure as ''Psaronius'', but are composed of central vascular bundles having smaller, O- and C-shaped forms, or wavy segments having a short, rounded or fat configuration. Leaf traces are poly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Fern
Tree ferns are arborescent (tree-like) ferns that grow with a trunk (botany), trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae (scaly tree ferns), Dicksoniaceae, Metaxyaceae, and Cibotiaceae. It is estimated that Cyatheales originated in the early Jurassic, and is the third group of ferns known to have given rise to tree-like forms. The others are the extinct ''Tempskya'' of uncertain position, and Osmundales where the extinct Guaireaceae and some members of Osmundaceae also grew into trees. In addition there were the Psaroniaceae including ''Tietea'' in the Marattiaceae, Marattiales, which is the sister group to all the leptosporangiate ferns. Other ferns which are also tree ferns, are ''Leptopteris'' and ''Todea'' in the family Osmundaceae, which can achieve short trunks under a metre tall. Osmunda regalis is sometimes considered a tree fern. Fern species with s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
