Athyrium

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Athyrium (family Aspleniaceae) A genus of ferns with large, soft rhizome scales, and 1–3 pinnate, soft, hairless fronds; sori are borne on receptacles on a side branch of a vein; indusia are hooked, or crescent-shaped, and toothed, or (rarely) absent. There are about 180 species. They are cosmopolitan, but most occur in temperate eastern Asia.