Polystichum setigerum (Presl) C. Presl

Polystichum setigerum is disjunct on Attu Island at the western tip of the Aleutian Archipelago. It is presumed to be of hybrid origin, the result of a cross between P . munitum and P . braunii (D. H. Wagner 1979). This hybrid has been produced experimentally (A. Sleep and T. Reichstein 1967) and is reported from British Columbia (see discussion under P . braunii ).

Stems erect. Leaves arching, 4--10 dm; bulblets absent. Petiole 1/8--1/5 length of leaf, densely scaly; scales light brown, gradually diminishing in size distally. Blade lanceolate, deeply 1-pinnate-pinnatifid to 2-pinnate, base narrowed. Pinnae lanceolate, not overlapping, in 1 plane, 4--8 cm, base oblique, margins incised to costa on middle pinnae, serrulate-spiny with teeth spreading-ascending, apex acute-apiculate with subapical and apical teeth same size; microscales filiform, sparse abaxially, confined to costa adaxially. Indusia erose-ciliate. Spores brown. 2 n = 246.

B.C.; Alaska.

Forest floor in lowland coastal forests; 0--250m.

Nephrodium setigerum C. Presl, Reliq. Haenk. 1: 37. 1825; P. braunii (Spenner) Fée subsp. alaskense (Maxon) Calder & R. L. Taylor; P. braunii var. alaskense (Maxon) Hultén

Polystichum setigerum là một loài thực vật có mạch trong họ Dryopteridaceae. Loài này được (C. Presl) C. Presl miêu tả khoa học đầu tiên năm 1836.