Pellaea bridgesii

Hooker

Sp. Fil. 2: 238, plate 142b. 1858.

Endemic
Treatment appears in FNA Volume 2.

Stems compact, ascending, stout, 5–10 mm diam.; scales mostly weakly bicolored, linear-subulate, 0.1–0.3 mm wide, centers dark-brown, thin, margins lighter, thin, denticulate to entire. Leaves monomorphic, clustered on stem, 7–30 cm; croziers nearly glabrous. Petiole dark-brown, lustrous, rounded adaxially, without prominent articulation lines. Blade linear, 1-pinnate, 1.5–4 cm wide; rachis brown throughout, straight, rounded adaxially, glabrous. Pinnae perpendicular to slightly ascending, usually not decurrent on rachis, simple and unlobed; costae absent. Ultimate segments broadly ovate to elliptic, 7–20 mm, leathery, glabrous; margins plane, not recurved, not covering abaxial surface, borders whitish, entire; apex obtuse to rounded. Veins of ultimate segments obscure. Sporangia sessile or subsessile, containing 64 spores, intermixed with abundant farina-producing glands. 2n = 58.


Phenology: Sporulating summer–fall.
Habitat: Rocky slopes and cliffs, on granitic substrates
Elevation: 1200–3600 m

Distribution

V2 407-distribution-map.gif

Calif., Idaho, Nev., Oreg.

Discussion

The morphology of Pellaea bridgesii is so distinctive that its sectional (and even generic) placement in Pellaea has long been a source of contention. W. H. Wagner Jr. et al. (1983) documented the existence of sterile diploid hybrids (called P. × glaciogena) between P. bridgesii and P. mucronata (see reticulogram), suggesting that P. bridgesii is most closely related to members of sect. Pellaea. In addition to the more obvious characters mentioned above, P. bridgesii is distinguished from other North American species (except P. ternifolia) by its anastomosing veins.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.

... more about "Pellaea bridgesii"
obtuse +  and rounded +
Michael D. Windham +
Hooker +
cordate +, truncate +  and rounded +
glabrous +  and pubescent +
linear +  and ovate-deltate +
1.5 cm15 mm <br />0.015 m <br /> (4 cm40 mm <br />0.04 m <br />) +
Calif. +, Idaho +, Nev. +  and Oreg. +
1200–3600 m +
yellow +  and white +
obcordate;reniform +
Rocky slopes and cliffs, on granitic substrates +
monomorphic +
clustered;widely scattered +
recurved +  and reflexed +
noncircinate +  and circinate +
7 cm70 mm <br />0.07 m <br /> (30 cm300 mm <br />0.3 m <br />) +
entire +, erose +  and dentate +
not recurved +
plane +, denticulate +  and entire +
pubescent +  and glabrous +
Sporulating summer–fall. +
perpendicular +  and slightly ascending +
persistent +
linear-subulate +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (?) +  and 0.03 cm0.3 mm <br />3.0e-4 m <br /> (?) +
subsessile +  and sessile +
brown +  and tan +
cristate +  and tetrahedral-globose +
dark colored +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Pellaea bridgesii +
species +
0.7 cm7 mm <br />0.007 m <br /> (2 cm20 mm <br />0.02 m <br />) +
crescent--shaped +  and roundish +
branched +  and anastomosing +