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Pteridaceae
See list of 4 genera in this family-
1a. Petiole apparently forking into two main divisions; sori borne on the surface of a false indusium, this best viewed through dissection; ultimate segments without a distinct midrib
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1b. Petiole not appearing to fork into two divisions; sori borne on the surface of the leaf blade near margin and covered by a false indusium; ultimate segments with a midrib
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2a. Leaf blade tissue pubescent with septate hairs; ultimate segments of reproductive leaves 3–5 mm long
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2b. Leaf blade tissue not pubescent (though the petioles and rachises may be pubescent); ultimate segments of reproductive leaves 5–75 mm long
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3a. Leaf blades thin, herbaceous to membranaceous, withering by late summer; rhizome scales colorless; leaves dimorphic—the reproductive ones with more elongate and relatively narrower segments compared with the vegetative ones; veins not reaching margins of ultimate segments
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3b. Leaf blades thick, coriaceous, persistent; rhizome scales red-brown; leaves monomorphic to hemidimorphic (e.g., the reproductive leaves somewhat longer and more divided than the vegetative leaves in P. atropurpurea); veins reaching margins of ultimate segments
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Each photo represents one genus in this family.