Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Polystichum kruckebergii

Polystichum andersonii

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

Anderson's holly-fern, Anderson's sword fern, Vancouver holly fern
Stems

ascending.

erect.
Leaves

erect, 1–2.5 dm;

bulblets absent.

monomorphic, arching, 3–10 dm;

bulblets 1 or more, on distal 1/3 of rachis.
Petiole

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

scales light brown, gradually diminishing in size distally.

1/8–1/4 length of leaf, densely scaly;

scales light brown, diminishing in size distally.
Blade

linear, 1-pinnate-pinnatifid, base narrowed.

lanceolate, 1-pinnate-pinnatifid;

base narrowed.
Pinnae

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.

lanceolate-falcate, proximal pinnae ± triangular, not overlapping, in 1 plane, 2–10 cm;

base oblique, acroscopic auricle well developed;

margins incised to costae, segments adnate to costa for at least 2 mm, serrulate-spiny with teeth ascending;

apex acute with subapical and apical teeth same size;

microscales filiform, with contorted projections, dense abaxially, sparse adaxially.
Indusia

entire.

sparsely ciliate.
Spores

dark brown.

light brown to brown.
2n

= 164.

= 164.

Polystichum kruckebergii

Polystichum andersonii
Habitat Rocks and cliffs in subalpine to alpine habitats Lowland coastal to midmontane forests, interior moist forests
Elevation 1500–3200 m (4900–10500 ft) 100–1700 m (300–5600 ft)
Distribution
from FNA
CA; ID; MT; NV; OR; UT; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; ID; MT; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Polystichum andersonii is an allotetraploid (D. H. Wagner 1979); its diploid parents are P. munitum and P. kwakiutlii. The triploid cross, P. munitum × andersonii, has been analyzed cytologically (W. H. Wagner Jr. 1973). It is the only sterile hybrid in the genus that develops large colonies through vegetative propagation by its bulblets. Hybrids look very much like some of the more deeply incised forms of Polystichum munitum except that they have abundant filiform scales, abortive sori, and nearly triangular lowermost pinnae with ± equally incised acroscopic and basiscopic auricles.

(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. kwakiutlii, P. lemmonii, P. lonchitis, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
P. acrostichoides, P. aleuticum, P. braunii, P. californicum, P. dudleyi, P. imbricans, P. kruckebergii, P. kwakiutlii, P. lemmonii, P. lonchitis, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
Synonyms P. braunii subsp. andersonii, P. braunii var. andersonii
Name authority W. H. Wagner: Amer. Fern J. 56: 4. (1966) M. Hopkins: Amer. Fern J. 3: 116, plate 9. (1913)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

The species comparison tool is brought to you by:
Northwest Wildflowers