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| 1 Sori elongate, indusia present and flaplike, attached along a long side. |
| ..2 Leaves 2-pinnate to 3-pinnate (the pinnae at least 1-pinnate); sori elongate, 2-3× as long as wide, the larger sori generally curved and extending across the veins (except Diplazium esculentum). |
....3 Veins free, simple or forked |
| ....3 Veins anastamosing |
| ..2 Leaves 1-pinnate to 1-pinnate-pinnatifid (the pinnae entire or pinnatifid); sori elongate, 2.5-6× as long as wide, even the larger sori generally straight and not extending across the veins. |
| ......4 Leaves 1-pinnate-pinnatifid, the pinnae pinnatifid |
| ......4 Leaves 1-pinnate, the pinnae entire |
| 1 Sori round, indusia present or absent, if present cuplike or lateral (but not attached along a long side). |
| ........5 Leaf blades broadly triangular in outline, ca. 1× as long as wide; rhizome ca. 1 mm in diameter; indusia absent; [native species of mountain peaks of n. NC and VA] |
| ........5 Leaf blades lanceolate, oblong, or ovate in outline, 2× or more as long as wide; rhizome more than 2 mm in diameter. |
| ..........6 Indusium attached under one side of the sorus, hoodlike or pocketlike, arching over the sorus; petioles glabrous or sparsely beset with scales, the petiole bases not persistent |
| ..........6 Indusium attached under the sorus, cuplike (divided into 3-6 lanceolate to ovate lobes which surround the sorus from below) or of minute numerous septate hairs, which extend out from under the sorus on all sides; petioles often densely beset with scales, the petiole bases persistent |
| 1 Leaves 1-pinnate to 1-pinnate-pinnatifid (the pinnae entire or pinnatifid); sori elongate, 2.5-6× as long as wide, even the larger sori generally straight and not extending across the veins. |
| ..2 Leaves 1-pinnate, the pinnae entire |
| ..2 Leaves 1-pinnate-pinnatifid, the pinnae pinnatifid |
| 1 Leaves 2-pinnate to 3-pinnate (the pinnae at least 1-pinnate); sori elongate, 2-3× as long as wide, the larger sori generally curved and extending across the veins (except Diplazium esculentum). |
| ....3 Veins anastamosing |
| ....3 Veins free, simple or forked. |
| ......4 Rhizomes short-creeping to ascending; leaves variegated, silvery gray and gray-green; [alien, rarely persisting or naturalizing] |
......4 Rhizomes erect; leaves not variegated, bright green; [native and widespread, sometimes cultivated] |