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Pteridaceae
Pteridaceae is a family of ferns in the order Polypodiales, including some 1150 known species in ca 45 genera (depending on taxonomic opinions), divided over five subfamilies. The family includes four groups of genera that are sometimes recognized as separate families: the adiantoid, cheilanthoid, pteridoid, and hemionitidoid ferns. Relationships among these groups remain unclear, and although some recent genetic analyses of the Pteridales suggest that neither the family Pteridaceae nor the major groups within it are all monophyletic, as yet these analyses are insufficiently comprehensive and robust to provide good support for a revision of the order at the family level. Description Members of Pteridaceae have creeping or erect rhizomes. The leaves are almost always compound and have linear sori that are typically on the margins of the leaves and lack a true indusium, typically being protected by a false indusium formed from the reflexed margin of the leaf. Taxonomy Tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adiantaceae
Vittarioideae is a subfamily of the fern family Pteridaceae, in the order Polypodiales. The subfamily includes the previous families Adiantaceae (adiantoids or maidenhair ferns) and Vittariaceae (vittarioids or shoestring ferns). Description The subfamily includes two distinct groups of ferns: the adiantoids, consisting of the single genus ''Adiantum'', and the vittarioids, several genera, including ''Vittaria'', which typically have highly reduced leaves, usually entire, and an epiphytic habit. The ferns historically considered as ''Adiantum'' include both petrophilic and terrestrial plants. The vittarioid ferns are primarily epiphyte, epiphytic in tropical regions and all have simple leaves with sorus, sori that follow the veins and lack true indusium, indusia; the sori are most often marginal with a false indusium formed from the reflexed leaf margin. The family also includes a species, ''Vittaria appalachiana'', that is highly unusual in that the sporophyte stage of the life c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
