Polystichum aleuticum

C. Christensen

in Hultén, Svensk Bot. Tidskr. 30: 515, fig. 1a. 1936.

EndemicConservation concern
Treatment appears in FNA Volume 2.

Stems erect. Leaves monomorphic, erect, 1–1.5 dm; bulblets absent. Petiole 1/6–1/4 length of leaf; scales tan, sparse or falling off early. Blade linear-lanceolate, 1-pinnate, gradually tapered to base. Pinnae ± deltate to ovate, slightly overlapping, in 1 plane, 4–8 mm; base truncate, acroscopic auricle well developed; margins denticulate, not spiny; apex rounded, not dentate; microscales linear, lacking projections, dense on both surfaces. Indusia entire to minutely erose-dentate. Spores brown.

Habitat: Growing in crevices of rocks
Elevation: 0–400 m


Polystichum aleuticum is known only from Atka and Adak islands, Alaska. Its nearest relatives are in southwest China. Polystichum aleuticum resembles the dwarfed plants of P. kruckebergii, but it differs, especially, in its smaller, more rounded pinna apices and more abundant scales.

Of conservation concern.

Selected References


Lower Taxa