Pellaea truncata
Pellaea gastonyi
cliff brake, spiny cliff-brake
Gastony's cliff-brake, Gastony's cliffbrake fern
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 uniformly reddish brown, linear-subulate, 0.1–0.3 mm wide, thin, margins entire to denticulate.
somewhat dimorphic, sterile leaves shorter and less divided than fertile leaves, clustered on stems, 8–40 cm;
croziers sparsely villous.
somewhat dimorphic, sterile leaves shorter than fertile leaves, clustered on stem, 8–25 cm;
croziers villous.
dark brown, lustrous, flattened or slightly grooved adaxially, without prominent articulation lines.
reddish purple to dark brown, lustrous, rounded adaxially, without prominent articulation lines.
ovate-deltate, usually 2-pinnate proximally, 4–18 cm wide;
rachis brown throughout, straight, shallowly grooved adaxially, usually glabrous.
elongate-deltate to lanceolate, 2-pinnate proximally, 3–6 cm wide;
rachis purple or brown throughout, straight, rounded adaxially, sparsely villous with long, divergent hairs.
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.
oblong-lanceolate, 7–30 mm, leathery, sparsely villous abaxially near midrib;
margins usually recurved on fertile segments, covering less than 1/2 abaxial surface, borders whitish, crenulate;
apex obtuse to slightly mucronate.
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.
ascending or perpendicular to rachis, not decurrent on rachis or obscurely so, usually with 3–7 ultimate segments;
costae straight, 2–30 mm, usually shorter than ultimate segments.
of ultimate segments obscure.
of ultimate segments obscure.
long-stalked, containing 64 spores, intermixed with abundant farina-producing glands.
long-stalked, containing 32 spores, not intermixed with farina-producing glands.
= 58.
Pellaea truncata
Pellaea gastonyi
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.)
Pellaea gastonyi is an apogamous tetraploid that has originated through repeated hybridization between P. atropurpurea and P. glabella. Isozyme studies (G. J. Gastony 1988) indicate that P. glabella subsp. missouriensis was the diploid parent of plants found in Missouri, whereas diploid P. glabella subsp. occidentalis was involved in the origin of P. gastonyi populations occurring in western North America. Pellaea gastonyi is most often confused with P. atropurpurea, from which it differs in having sparsely villous rachises, smaller ultimate segments, and spores averaging more than 62 µm in diameter.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
BC
WA
Flora NW
MO Plants
PNW Herbaria
