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 microchlamys

Polystichum californicum

attu hollyfern

California sword-fern
Stems

erect.

erect or ascending.
Leaves

arching, 3–8 dm;

bulblets absent.

monomorphic, arching or erect, 2–8 dm;

bulblets absent.
Petiole

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

scales brown, diminishing in size distally.

1/5–1/3 length of leaf;

scales light brown, abruptly diminishing in size distally, falling off early distally.
Blade

broadly lanceolate, 1-pinnate-pinnatifid, base slightly narrowed.

lanceolate to linear-lanceolate, 1-pinnate-pinnatifid, base slightly narrowed.
Pinnae

narrowly lanceolate, not overlapping, in 1 plane, 3–13 cm;

base oblique, proximal acroscopic segments enlarged;

margins incised to costa but segments sessile and adnate to costa for at least 2 mm, segments excised and decurrent, serrulate-spiny with teeth spreading to ascending;

apex acute with subapical and apical teeth same size;

microscales filiform, dense abaxially, sparse adaxially.

oblong to lanceolate to falcate, shallowly to deeply divided, pinnae overlapping or not, in 1 plane, 2–10 cm;

base oblique, acroscopic auricle lobed;

margins not incised to costae, serrulate-spiny with teeth ascending;

apex acute-attenuate, subapical and apical teeth same size (southern form) or obtuse and cuspidate with subapical teeth smaller than apical teeth (northern form);

microscales filiform, dense abaxially, sparse adaxially.
Indusia

erose-dentate.

ciliate.
Spore(s)

color unknown.

brown.
2n

= 164.

Polystichum microchlamys

Polystichum californicum
Habitat Terrestrial On forest floor in southern part of range and in rock crevices at cliff bottoms (most commonly andesite) to north
Elevation 0–100 m (0–300 ft) 100–850 m (300–2800 ft)
Distribution
from FNA
AK; Asia in Kamtchatka and Japan
[BONAP county map]
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Polystichum microchlamys is found in the flora only on Attu, at the western tip of the Aleutian Archipelago.

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

Polystichum californicum is restricted to the Coast Ranges and the Sierra-Cascade axis. It is most abundant in the Coast Range north of San Francisco.

Polystichum californicum is an allopolyploid, the evolutionary roots of which include P. dudleyi as the 2-pinnate ancestor. Morphologic and ecological data indicate P. imbricans is ancestor to the northern forms and P. munitum is ancestor to southern forms, suggesting P. californicum is an amalgam of interfertile tetraploids with polyphyletic origins (D. H. Wagner 1979). Cytological analysis corroborates this (A. D. Callan 1972; W. H. Wagner Jr. 1973), but chloroplast DNA studies have detected only the involvement of P. imbricans in the ancestry of P. californicum (P. S. Soltis et al. 1991).

The more xeric, rock-inhabiting members of the complex (showing the parental influence of P. imbricans) occupy the northern half of the range whereas plants of more mesic habitats are found to the south. Hybrids with both P. dudleyi and P. munitum are found frequently, because these three species are often sympatric (W. H. Wagner 1973). The hybrid with P. dudleyi (a triploid) will key to that species. The hybrid with P. munitum resembles a less-incised form of P. californicum with aborted sporangia. Polystichum californicum × imbricans has been found only once, in Oregon (A. D. Callan 1972). Another hybrid that will key here, based on its overall appearance, is P. munitum × scopulinum. It lacks filiform microscales and also has malformed sporangia. Such a specimen was the basis of the report of Polystichum californicum in eastern Washington (C. L. Hitchcock et al. 1955–1969, vol. 1). The sterile diploid hybrid between P. dudleyi and P. munitum is indistinguishable from P. californicum except for aborted sporangia and chromosome number (W. H. Wagner Jr. 1973).

(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. lonchitis, P. munitum, P. scopulinum, P. setigerum
P. acrostichoides, P. aleuticum, P. andersonii, P. braunii, P. dudleyi, P. imbricans, P. kruckebergii, P. kwakiutlii, P. lemmonii, P. lonchitis, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
Synonyms Aspidium microchlamys Aspidium californicum, P. aculeatum var. californicum
Name authority (H. Christ) Matsumura: Index Pl. Jap. 1: 343. (1904) (D. C. Eaton) Diels: in Engler & Prantl, Nat. Pflanzenfam. 1(4): 191. (1899)
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 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