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 braunii

attu hollyfern

Braun's holly-fern, polystic de Braun
Stems

erect.

erect.
Leaves

arching, 3–8 dm;

bulblets absent.

monomorphic, arching, 2–10 dm;

bulblets absent.
Petiole

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

scales brown, diminishing in size distally.

1/8–1/6 length of leaf, densely scaly;

scales light brown, gradually diminishing in size distally.
Blade

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

broadly lanceolate, 2-pinnate;

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

base oblique except proximal 3–4 pinnae, where auricles not developed;

apex acute, subapical and apical teeth same size;

microscales filiform to linear, lacking projections, dense abaxially, sparse adaxially.
Indusia

erose-dentate.

ciliate.
Spore(s)

color unknown.

brown.
Pinnules

± stalked, short-falcate to oblique-rhombic, acroscopic auricle well developed on proximal pinnules;

margins dentate, with slender bristle tips;

apex broadly acute.
2n

= 164.

Polystichum microchlamys

Polystichum braunii
Habitat Terrestrial Moist places in boreal forests, interior moist forests
Elevation 0–100 m (0–300 ft) 0–300 m (0–1000 ft)
Distribution
from FNA
AK; Asia in Kamtchatka and Japan
[BONAP county map]
from FNA
AK; CT; ID; MA; ME; MI; MN; NH; NY; VT; WI; BC; NB; NF; NS; ON; QC; YT; SPM; Eurasia
[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.)

Because no diploid ancestors have been found, Polystichum braunii is thought to be an ancient tetraploid. Its sterile hybrid with P. acrostichoides, P. × potteri, is discussed under P. acrostichoides. Polystichum braunii × lonchitis has been reported from southeast Alaska (S. L. Welsh 1974). This hybrid has been cytologically confirmed in Europe and named P. × meyeri Sleep & Reichstein (A. Sleep and T. Reichstein 1967). It has narrower and less divided leaves than P. braunii and poorly developed auricles. Polystichum braunii × lonchitis was described by J. Ewan (1944), but the type (from British Columbia) is P. braunii × munitum (A. Sleep and T. Reichstein 1967). This latter hybrid is the postulated progenitor of P. setigerum (D. H. Wagner 1979). North American P. braunii has been segregated as var. purshii Fernald, distinguished from European populations (var. braunii) by having broader microscales.

(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. californicum, P. dudleyi, P. imbricans, P. kruckebergii, P. kwakiutlii, P. lemmonii, P. lonchitis, P. microchlamys, P. munitum, P. scopulinum, P. setigerum
Synonyms Aspidium microchlamys Aspidium braunii, P. braunii subsp. purshii, P. braunii var. purshii
Name authority (H. Christ) Matsumura: Index Pl. Jap. 1: 343. (1904) (Spenner) Fée
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, UW Burke Herbarium

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