Pellaea mucronata |
Pellaea mucronata subsp. californica |
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bird's-foot fern, birdfoot cliffbrake |
bird's foot fern |
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Stems | compact, ascending, stout, 5–10 mm diam.; scales bicolored, linear-subulate, 0.1–0.3 mm wide, centers black, thick, margins brown, thin, erose-dentate. |
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Leaves | monomorphic, clustered on stem, 7–45 cm; croziers sparsely villous. |
blade usually 2-pinnate proximally; pinnae ascending and overlapping, especially in distal portion of leaf. |
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Petiole | dark brown, lustrous, flattened to slightly grooved adaxially, without prominent articulation lines. |
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Blade | ovate-deltate, (2–)3-pinnate proximally, 4–18 cm wide; rachis brown throughout, straight, shallowly grooved adaxially, usually glabrous. |
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Ultimate segments | narrowly oblong, 2–12 mm, leathery, glabrous; margins recurved to strongly revolute on fertile segments, usually covering more than 1/2 abaxial surface, borders greenish, usually dentate; apex mucronate. |
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Pinnae | perpendicular to rachis to strongly ascending, not decurrent on rachis, usually with 9–40 ultimate segments; costae straight, 10–70 mm, much longer than ultimate segments. |
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Veins | of ultimate segments obscure. |
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Sporangia | short-stalked, containing 64 spores, intermixed with abundant farina-producing glands. |
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Pellaea mucronata |
Pellaea mucronata subsp. californica |
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Phenology | Sporulating summer–fall. | |||||
Habitat | Cliffs and rocky slopes, usually on granitic substrates | |||||
Elevation | 1800–3000 m (5900–9800 ft) | |||||
Distribution |
CA; NV; Mexico
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CA |
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Discussion | Subspecies 2 (2 in the flora). Pellaea mucronata encompasses two morphologic extremes that tend to occupy different habitats and are treated here as subspecies. The typical 3-pinnate form (P. mucronata subsp. mucronata) is scattered throughout California and southern Nevada, usually below 1800 m elevation. The 2-pinnate form with ascending, overlapping pinnae (P. mucronata subsp. californica) is apparently confined to the Sierra Nevada and Transverse Ranges of California at elevations greater than 1800 m. The taxonomic status of these entities remains in dispute, and they are often treated as mere ecological forms. W. H. Wagner Jr. et al. (1983) indicated that natural hybrids formed between P. bridgesii and these two taxa are morphologically distinct, suggesting that the differences observed between the subspecies of P. mucronata are genetically based. In addition to P. bridgesii, subsp. mucronata apparently hybridizes with both P. truncata and P. brachyptera (see comments under those species). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 2, p. 182. | FNA vol. 2. | ||||
Parent taxa | Pteridaceae > Pellaea | Pteridaceae > Pellaea > Pellaea mucronata | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Allosorus mucronatus, P. ornithopus | P. wrightiana var. californica, P. compacta, P. mucronata var. californica | ||||
Name authority | (D. C. Eaton) D. C. Eaton: in Emory, Rep. U.S. Mex. Bound. 2(1): 233. (1859) | (Lemmon) Windham: Contr. Univ. Michigan Herb. 19: 42. (1993) | ||||
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