Polystichum dudleyi

Maxon

J. Wash. Acad. Sci. 8: 620. 1918.

Common names: Dudley's sword fern
Endemic
Synonyms: Polystichum aculeatum var. dudleyi (Maxon) Jepson
Treatment appears in FNA Volume 2.

Stems erect. Leaves monomorphic, arching, 2–10 dm; bulblets absent. Petiole 1/5–1/3 length of leaf, densely scaly; scales light-brown, gradually diminishing in size distally. Blade broadly lanceolate, 2-pinnate, base not narrowed. Pinnae narrowly lanceolate, not overlapping, in 1 plane, 3–13 cm; base oblique, apex acute with subapical and apical teeth same size; microscales filiform, lacking projections, sparse abaxially, but longer than in other Polystichum species, forming loosely tangled network over blade and sori (such network only in this species), sparse adaxially. Pinnules ± stalked, linear-falcate to oblique-rhombic, acroscopic auricle well developed on proximal pinnules; margins spinulose-dentate; apex acute. Indusia ciliate. Spores brown. 2n = 82.


Habitat: Moist forests
Elevation: 0–100 m

Discussion

Polystichum dudleyi is confined to coastal central California. Hybrids with P. californicum are relatively frequent where these species occur together. These hybrids would key here but, unlike P. dudleyi, they are less divided and have aborted sporangia. The sterile diploid hybrid with P. munitum is also frequent in areas of sympatry. It is indistinguishable from P. californicum except for malformed sporangia and chromosome number (W. H. Wagner Jr. 1973).

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property."/5lengthofleaf" is not declared as a valid unit of measurement for this property.

... more about "Polystichum dudleyi"
David H. Wagner +
not narrowed +
simple to commonly +
network +  and tangled +
lanceolate +
reduced +
leathery;leathery +
roundish +
Dudley's sword fern +
0–100 m +
inflated +
often +  and glabrous +
Moist forests +
caducous +  and persistent +
monomorphic +
evergreen +
not articulate +
spinulose-toothed +
3 cm30 mm <br />0.03 m <br /> (13 cm130 mm <br />0.13 m <br />) +
linear-falcate +  and oblique-rhombic +
sessile +  and short-petiolulate +
J. Wash. Acad. Sci. +
round +, cuplike +, hoodlike +, reniform +, falcate +  and linear +
2 +  and 3 +
light-brown +
persistent +
scaly +  and glabrous +
linear;lanceolate +
diminishing +
network +  and tangled +
discrete +
reniform +  and oblong +
dictyostelic +, unbranched +  and branched +
Polystichum aculeatum var. dudleyi +
Polystichum dudleyi +
Polystichum +
species +
anastomosing +
epiphytic +  and hemiepiphytic +