Pellaea mucronata |
Pellaea brachyptera |
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bird's-foot fern, birdfoot cliffbrake |
Sierra cliff-brake, Sierran cliffbrake |
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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. |
compact, ascending, stout, 5–10 mm diam.; scales bicolored, linear-subulate, 0.1–0.3 mm wide, centers dark brown to black, thick, margins brown, thin, dentate. |
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Leaves | monomorphic, clustered on stem, 7–45 cm; croziers sparsely villous. |
monomorphic, clustered on stem, 8–40 cm; croziers sparsely villous. |
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Petiole | dark brown, lustrous, flattened to slightly grooved adaxially, without prominent articulation lines. |
dark brown, lustrous, flattened or 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. |
linear-oblong, 2-pinnate proximally, 1–4 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. |
linear, 5–20 mm, leathery, glabrous; margins on fertile segments strongly revolute, covering more than 1/2 abaxial surface, borders greenish, crenate; 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. |
strongly ascending, not decurrent on rachis, usually with 5–11 ultimate segments; costae straight, 5–20 mm, usually shorter than ultimate segments. |
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Veins | of ultimate segments obscure. |
of ultimate segments obscure. |
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Sporangia | short-stalked, containing 64 spores, intermixed with abundant farina-producing glands. |
short-stalked, containing 64 spores, intermixed with abundant farina-producing glands. |
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Pellaea mucronata |
Pellaea brachyptera |
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Phenology | Sporulating summer–fall. | |||||
Habitat | Cliffs and rocky slopes, usually on igneous substrates, occasionally on serpentine | |||||
Elevation | 900–2700 m (3000–8900 ft) | |||||
Distribution |
CA; NV; Mexico
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CA; OR; WA
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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.) |
The distinctive Pellaea brachyptera reportedly hybridizes with P. mucronata (A. F. Tryon 1957; D. B. Lellinger 1985); the hybrids are morphologically intermediate plants with malformed spores. (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 | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Allosorus mucronatus, P. ornithopus | Platyloma brachyptera | ||||
Name authority | (D. C. Eaton) D. C. Eaton: in Emory, Rep. U.S. Mex. Bound. 2(1): 233. (1859) | (T. Moore) Baker: in Hooker & Baker, Syn. Fil. ed. 2 477. (1874) | ||||
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