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Dennstaedtia resources
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Dennstaedtia Bernhardi (Dennstaedtiaceae) Earlier placement: Polypodiaceae, Hypolepidaceae

Cup fern

Etymology Named for the German botanist, August Wilhelm Dennstaedt (1776-1826).
Description Rhizome: long-creeping, hairs dark reddish brown, jointed.
Frond: deciduous, monomorphic.
Stipe: straw-colored to brown, darker at base, grooved above, pubescent with soft, jointed hairs, vascular bundles: 1 arranged in a U-shape.
Blade: 2-pinnate-pinnatifid, less and more also, lanceolate, lacy, papery, yellow-green to pale green, indument of silver-gray, jointed hairs on both surfaces, gland tipped hairs below.
Pinnae: broadest at the base, segments ovate to lanceolate, margins serrate-crenate, veins free, pinnately branched.
Sori: globose to almost cylindric, marginal at vein tips, indusium: formed by fusion of inner and outer laminar flaps to form a circular cup.
Dennstaedtia. Sori here are less than 2 mm, with cup-like indusia constructed partly from the margin, partly from the lamina.  Photo by Rod Tulloss, Environmental Commission of the Borough of Roosevelt and the Fund for Roosevelt, Inc.
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