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Woodsia

Reference: Windham (1993b).

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W. obtusa
1a. Petioles not articulated, therefore the persistent petiole bases of various lengths; leafules dentate with pointed teeth; petiole scales bicolored, with a dark central region; leaf blades (8–) 20–60 cm long
See list of 3 species in 1b
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1b. Petioles articulated, therefore the persistent petiole bases mostly of equal length, the articulation point noticeable as a slightly swollen node; leafules entire to crenate; petiole scales concolored; leaf blades 2.5–22 (–25) cm long
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  W. glabella
  2a. Plants glabrous, with sessile glands; basal leaflets flabellate; leaf blades 1–1.5 cm wide; petioles green to light brown
- See list of 2 species in 2b
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  2b. Plants with hairs, scales, and/or stalked glands; basal leaflets narrowly ovate to deltate; leaf blades 1–3 cm wide; petioles brown to dark brown
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    W. alpina
    3a. Leaflets glabrous or nearly so on the abaxial surface (though scales may be present on the rachis and costae), the larger leaflets with 2 or 3 pairs of leafules; indusium composed of few filaments
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    W. ilvensis
    3b. Leaflets with scales on the abaxial surface, the larger leaflets with 4–7 pairs of leafules; indusium composed of many filaments

Show photos of: Each photo represents one species in this genus.