Pellaea truncata |
Pellaea ternifolia |
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cliff brake, spiny cliff-brake |
trans-Pecos 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 black, thick, margins brown, thin, erose-dentate. |
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Leaves | somewhat dimorphic, sterile leaves shorter and less divided than fertile leaves, clustered on stems, 8–40 cm; croziers sparsely villous. |
monomorphic, clustered on stem, 10–50 cm; croziers sparsely to densely villous. |
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Petiole | dark brown, lustrous, flattened or slightly grooved adaxially, without prominent articulation lines. |
black or dark purple, lustrous, rounded or slightly flattened adaxially, without prominent articulation lines. |
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Blade | ovate-deltate, usually 2-pinnate proximally, 4–18 cm wide; rachis brown throughout, straight, shallowly grooved adaxially, usually glabrous. |
linear to ovate, deeply pinnate-pinnatifid proximally, 2.5–8 cm wide; rachis black or purple throughout, straight, often flattened adaxially, glabrous or villous. |
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Ultimate segments | narrowly oblong, 4–10 mm, leathery, glabrous; margins recurved on fertile segments, usually covering less than 1/2 abaxial surface, borders whitish, nearly entire; apex mucronate. |
linear-oblong, 10–40 mm, leathery, glabrous to sparsely villous abaxially on midrib; margins recurved on fertile segments, rarely covering more than 1/2 abaxial surface, borders whitish, entire; apex mucronate. |
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Pinnae | perpendicular to rachis to slightly ascending, not decurrent on rachis, usually with 9–25 ultimate segments; costae straight, 20–70 mm, much longer than fertile ultimate segments. |
perpendicular to rachis or slightly ascending, not decurrent on rachis, ternate at base of leaf; costae absent. |
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Veins | of ultimate segments obscure. |
of ultimate segments obscure. |
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Sporangia | long-stalked, containing 64 spores, intermixed with abundant farina-producing glands. |
long-stalked, containing 64 spores, not intermixed with farina-producing glands. |
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2n | = 58. |
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Pellaea truncata |
Pellaea ternifolia |
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Phenology | Sporulating late spring–fall. | |||||||||
Habitat | Cliffs and rocky slopes, on various substrates but rarely observed on limestone | |||||||||
Elevation | 600–2500 m (2000–8200 ft) | |||||||||
Distribution |
AZ; CA; CO; NM; NV; TX; UT; n Mexico
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AZ; TX; Mexico; Central America; South America; Pacific Islands in Hawaii
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Discussion | Most manuals refer to Pellaea truncata as P. longimucronata, a name shown to be invalid by A. Cronquist et al. (1972+, vol. 1). Populations located near the range of P. mucronata in the Mojave Desert are often difficult to identify because of the subtlety of the characters involved and an apparent tendency to produce sterile (and possibly fertile) hybrids. Morphologically intermediate hybrids between P. truncata and P. wrightiana are common in regions where the ranges of the two species overlap, but these are easily identified by their malformed spores. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Subspecies 3 (3 in the flora). Pellaea ternifolia is represented in the flora by three morphologically and chromosomally distinct taxa. These discrete genetic entities also show a tendency toward geographic isolation and are treated here as subspecies. Diploid populations referred to P. ternifolia subsp. ternifolia are scattered from Texas through Mexico to South America. The pubescent tetraploid (P. ternifolia subsp. villosa) follows the Sierra Madre Oriental from Puebla, Mexico, north to Texas; the glabrous tetraploid (P. ternifolia subsp. arizonica) occurs in Arizona, Texas, and northern Mexico. Isozyme and chromosome studies suggest that both tetraploids are segmental allopolyploids produced by hybridization between subsp. ternifolia and other (as yet unidentified) diploid elements within P. ternifolia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 2. | FNA vol. 2, p. 180. | ||||||||
Parent taxa | Pteridaceae > Pellaea | Pteridaceae > Pellaea | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | P. longimucronata, P. wrightiana var. longimucronata | Pteris ternifolia | ||||||||
Name authority | Goodding: Muhlenbergia 8: 94. (1912) | (Cavanilles) Link: Fil. Spec. 59. (1841) | ||||||||
Web links |