Pellaea intermedia |
Pellaea breweri |
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creeping cliff brake, intermediate cliffbrake |
Brewer's cliff-brake, Brewer's cliffbrake fern |
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Stems | creeping, horizontal, slender, 2–4 mm diam.; scales mostly bicolored, narrowly lanceolate, largest scales 0.3–0.8 mm wide, centers black, thick, margins brown, thin, irregularly dentate. |
compact, ascending, stout, 5–10 mm diam.; scales uniformly reddish brown, linear-subulate, 0.1–0.3 mm wide, thin, margins sinuous, nearly entire. |
Leaves | monomorphic, widely scattered along stem, 12–50 cm; croziers pubescent and bearing a few scales. |
monomorphic, clustered on stem, 2.5–20 cm; croziers sparsely villous. |
Petiole | straw-colored, tan, or gray, not lustrous, rounded or slightly flattened adaxially, without prominent articulation lines. |
brown, lustrous, rounded adaxially, with prominent articulation lines near base. |
Blade | ovate to elongate-deltate, usually 2-pinnate proximally, 4–20 cm wide; rachis tan throughout, straight to slightly flexuous, rounded or flattened adaxially, ± pubescent. |
linear-oblong, pinnate-pinnatifid proximally, 1–4 cm wide; rachis brown proximally, green distally, straight, rounded adaxially, glabrous to sparsely villous. |
Ultimate segments | ovate to elliptic, 5–15 mm, leathery, glabrous or usually puberulent abaxially; margins recurved on fertile segments, usually covering less than 1/2 abaxial surface, borders whitish, nearly entire; apex obtuse to slightly mucronate. |
lanceolate-deltate, 5–25 mm, herbaceous, glabrous; margins recurved on fertile segments, covering less than 1/2 abaxial surface, borders whitish, erose-denticulate; apex obtuse or rounded. |
Pinnae | perpendicular to rachis or slightly ascending, not decurrent on rachis, usually with 7–21 ultimate segments; costae straight to slightly flexuous, 20–100 mm, longer than ultimate segments. |
ascending or perpendicular to rachis, decurrent on rachis, deeply 2-lobed (mitten-shaped) near base of leaf; costae absent. |
Veins | of ultimate segments obscure. |
of ultimate segments evident. |
Sporangia | short-stalked, containing 32 spores, not intermixed with farina-producing glands. |
sessile or subsessile, containing 64 spores, not intermixed with farina-producing glands. |
n | = 2n = 87, 116, apogamous. |
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2n | = 58. |
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Pellaea intermedia |
Pellaea breweri |
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Phenology | Sporulating summer–fall. | Sporulating summer–fall. |
Habitat | Rocky slopes and ledges, on a variety of substrates, including limestone and granite | Cliffs and rocky slopes, on a variety of substrates including granite and limestone |
Elevation | 300–2400 m (1000–7900 ft) | 1600–3800 m (5200–12500 ft) |
Distribution |
AZ; NM; TX; n Mexico
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CA; CO; ID; MT; NV; OR; UT; WA; WY
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Discussion | Plants of Pellaea intermedia in the flora are apogamous triploids and tetraploids; a sexual diploid cytotype has been found near Saltillo, Mexico (A. F. Tryon 1968). Given the high degree of morphologic similarity among the three cytotypes, the North American polyploids probably were derived from the Mexican diploid through autopolyploidy. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pellaea breweri is distinguished from other North American taxa (except for some populations of P. glabella) by the presence of prominent articulation lines near the base of the petiole. The leaves are easily detached, and many herbarium specimens consist of separate leaves and stems, the latter covered with petiole bases of approximately equal length. (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 | P. intermedia var. pubescens | |
Name authority | Mettenius ex Kuhn: Linnaea 38: 84. (1869) | D. C. Eaton: Proc. Amer. Acad. Arts 6: 555. (1865) |
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