Pteridaceae is itself in turn sometimes further subdivided

• One of a number of families into which the family Polypodiaceae has been subdivided in some classification systems

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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. Members of the family have creeping or erect rhizomes and are mostly terrestrial ...