Cheilanthes gracillima D. C. Eaton

Lace fern

Etymology Gracillima means most graceful.
Description Rhizome: short-creeping, scales light brown or orange, linear.
Frond: 25 cm high by 8 cm wide, deciduous, monomorphic, blade/stipe ratio: 1:1 or less.
Stipe: dark brown, rounded above, the color extending into the rachis and costae, nearly glabrous with a few linear scales, vascular bundles: 1.
Blade: 2-pinnate, oblong-lanceolate, noncircinate vernation, wooly, branched hairs dense below, sparse above.
Pinnae: 15 to 20 pair, usually equilateral; costae brown at base, becoming green, scales below inconspicuous; segments oblong or rarely oval, convex, the largest 1.5--3 mm; margins inrolled; veins free, obscure.
Sori: linear ± continuous around segment margins, submarginal, indusium: false, sporangia: black, maturity: summer to fall.
Culture Habitat: cliffs and rocky slopes, usually on igneous substrates, sometimes serpentine. Distribution: western North America, British Columbia, western Montana south to Califormia. Hardy to -25°C, USDA Zone 5.
Distinctive Characteristics Closest to C. tomentosa, but less divided and sparsely hairy on the upper blade surface.
Synonyms
Myriopteris gracillima (D. C. Eaton) J. Smith
Cheilanthes gracillima
Cheilanthes gracillima. Top:lower pinna surface; bottom: rhizome scale.  Illustration by Edgar Paulton, from How to Know the Ferns and Fern Allies, John T. Mickel, © 1979 Wm. C. Brown Co.
Cheilanthes gracillima
Cheilanthes gracillima. a) fronds, b) sterile pinna, c) fertile pinna.  Illustration by V. Fulford from Ferns and Fern Allies of Canada, William J. Cody and Donald M. Britton, 1989, © Agriculture Canada, used with permission.
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