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holly fern, mountain fern, northern holly fern, polystic faux-lonchitis

holly fern, Kruckeberg's holly fern, Kruckeberg's sword fern, Kruckeberg's sword fern fern

Stems

erect to occasionally ascending.

ascending.

Leaves

erect, not arching except at tip, 1–6 dm;

bulblets absent.

erect, 1–2.5 dm;

bulblets absent.

Petiole

1/10–1/6 of blade, densely scaly;

scales light brown, gradually diminishing in size distally.

1/10–1/5 length of leaf, sparsely scaly;

scales light brown, gradually diminishing in size distally.

Blade

linear, often widest above middle, 1-pinnate, base narrowed.

linear, 1-pinnate-pinnatifid, base narrowed.

Pinnae

oblong to lanceolate to falcate, proximal pinnae ± deltate, rarely overlapping, in 1 plane, 0.5–3 cm, base truncate to oblique, acroscopic auricle well developed;

margins serrulate-spiny with teeth spreading;

apex acute, subapical tooth hardly smaller than apical tooth;

microscales dense, on abaxial surface only.

rhombic-ovate to short-falcate, proximal pinnae ± triangular;

pinnae overlapping, twisted somewhat out of plane of blade, 0.5–1.5 cm;

base oblique, acroscopic auricle well developed;

margins shallowly incised to merely dentate or serrulate, teeth spreading and spiny at tip;

apex acute with subapical and apical teeth same size;

microscales lanceolate with few projections, confined to costa, on abaxial surface only.

Indusia

entire or minutely dentate-erose.

entire.

Spores

dark brown.

dark brown.

2n

= 82.

= 164.

Polystichum lonchitis

Polystichum kruckebergii

Habitat In rock crevices or at base of boulders, mostly in boreal and subalpine coniferous forests or alpine regions Rocks and cliffs in subalpine to alpine habitats
Elevation 0–3200 m (0–10500 ft) 1500–3200 m (4900–10500 ft)
Distribution
from FNA
AK; AZ; CA; CO; ID; MI; MN; MT; NV; OR; UT; WA; WI; WY; AB; BC; NF; NS; ON; QC; YT; Greenland
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; MT; NV; OR; UT; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

The hybrid between Polystichum lonchitis and P. acrostichoides (= P. × hagenahii Cody) is discussed under P. acrostichoides. The hybrid with P. braunii (= P. × meyeri Sleep & Reichstein) is discussed under P. braunii. In the Georgian Bay area of Ontario, P. lonchitis hybridizes with Dryopteris goldieana to produce the peculiar × Dryostichum singulare W. H. Wagner (W. H. Wagner Jr., F. S. Wagner et al. 1992).

The spiny spores of P. lonchitis are distinctive and distinguish this from dwarfed forms of other 1-pinnate species.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Polystichum kruckebergii is widely but sporadically distributed in small numbers in both the Sierra-Cascade and Rocky Mountain systems. Populations sometimes consist of only two or three dwarfed plants that are difficult to distinguish from P. scopulinum, with which they may occur. The spreading teeth of equal size at the pinna apex will usually distinguish this species. Polystichum kruckebergii is a tetraploid presumed to be of hybrid origin, with P. lonchitis and P. lemmonii as its diploid progenitors (W. H. Wagner Jr. 1973), although this hypothesis has not been confirmed. The hybrid with P. munitum has been found in Washington (P. S. Soltis et al. 1987) with both parents, and it is distinguished by intermediate morphology and abortive sporangia.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 2. FNA vol. 2.
Parent taxa Dryopteridaceae > Polystichum Dryopteridaceae > Polystichum
Sibling taxa
P. acrostichoides, P. aleuticum, P. andersonii, P. braunii, P. californicum, P. dudleyi, P. imbricans, P. kruckebergii, P. kwakiutlii, P. lemmonii, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
P. acrostichoides, P. aleuticum, P. andersonii, P. braunii, P. californicum, P. dudleyi, P. imbricans, P. kwakiutlii, P. lemmonii, P. lonchitis, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
Synonyms Polypodium lonchitis
Name authority (Linnaeus) Roth: Tent. Fl. Germ. 3(1): 71. (1799) W. H. Wagner: Amer. Fern J. 56: 4. (1966)
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