Pellaea brachyptera |
Pellaea wrightiana |
|
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Sierra cliff-brake, Sierran cliffbrake |
Wright's cliffbrake |
|
Stems | 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. |
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. |
Leaves | monomorphic, clustered on stem, 8–40 cm; croziers sparsely villous. |
monomorphic, clustered on stem, 6–40 cm; croziers sparsely villous. |
Petiole | dark brown, lustrous, flattened or slightly grooved adaxially, without prominent articulation lines. |
dark brown, lustrous, flattened or slightly grooved adaxially, without prominent articulation lines. |
Blade | linear-oblong, 2-pinnate proximally, 1–4 cm wide; rachis brown throughout, straight, shallowly grooved adaxially, usually glabrous. |
linear-oblong, 2-pinnate proximally, 1.5–5 cm wide; rachis brown throughout, straight, shallowly grooved adaxially, usually glabrous. |
Ultimate segments | linear, 5–20 mm, leathery, glabrous; margins on fertile segments strongly revolute, covering more than 1/2 abaxial surface, borders greenish, crenate; apex mucronate. |
narrowly oblong, 5–20 mm, leathery, glabrous; margins recurved on fertile segments, usually covering less than 1/2 abaxial surface, borders whitish, crenulate; apex mucronate. |
Pinnae | strongly ascending, not decurrent on rachis, usually with 5–11 ultimate segments; costae straight, 5–20 mm, usually shorter than ultimate segments. |
perpendicular to rachis or slightly ascending, not decurrent on rachis, usually with 3–9 ultimate segments; costae straight, 2–20 mm, usually shorter than ultimate segments. |
Veins | of ultimate segments obscure. |
of ultimate segments obscure. |
Sporangia | short-stalked, containing 64 spores, intermixed with abundant farina-producing glands. |
long-stalked, containing 64 spores, intermixed with sparse farina-producing glands. |
2n | = 116. |
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Pellaea brachyptera |
Pellaea wrightiana |
|
Phenology | Sporulating summer–fall. | Sporulating summer–fall. |
Habitat | Cliffs and rocky slopes, usually on igneous substrates, occasionally on serpentine | Cliffs and rocky slopes, on a variety of acidic to mildly basic substrates |
Elevation | 900–2700 m (3000–8900 ft) | 300–2900 m (1000–9500 ft) |
Distribution |
CA; OR; WA
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AZ; CO; NC; NM; OK; TX; UT; n Mexico
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Discussion | 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.) |
W. H. Wagner Jr. (1965) suggested that Pellaea wrightiana was a fertile allotetraploid hybrid between P. truncata (as P. longimucronata) and P. ternifolia. This hypothesis has been confirmed by isozyme analyses (M. D. Windham 1988). Pellaea wrightiana is therefore treated as a distinct species rather than a variety of P. ternifolia. This tetraploid species hybridizes with P. truncata and P. ternifolia subsp. arizonica to produce sterile triploids and tetraploids with intermediate morphology and malformed spores. Pellaea wrightiana has also hybridized with P. atropurpurea to form a rare apogamous pentaploid known only from western Oklahoma. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 2. | FNA vol. 2. |
Parent taxa | Pteridaceae > Pellaea | Pteridaceae > Pellaea |
Sibling taxa | ||
Synonyms | Platyloma brachyptera | P. ternifolia var. wrightiana |
Name authority | (T. Moore) Baker: in Hooker & Baker, Syn. Fil. ed. 2 477. (1874) | Hooker: Sp. Fil. 2: 142. (1858) |
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