Japan Flora: Rhizomes stout, erect, 2-4 cm. across; fronds tufted; stipes 4-6 cm. long, 2-2.5 mm. wide, erect, lustrous, dark brown and densely scaly especially at base, chestnut-brown above, the scales membranous, lanceolate to ovate, 1-1.3 cm. long, erose-ciliolate; blades linear-oblanccolate, 15-30 cm. long, 1.5-5 cm. wide, acuminate, gradually narrowed at base, simply pinnate; pinnae 30-50 pairs, firmly coriaceous, spreading, often spine-toothed, firmly spine-tipped, glabrous on upper side, with linear-lanceolate to linear, hyaline, entire scales beneath, ses­sile, auriculate-truncate on anterior side, cuneate on posterior side at base, the lower pinnae deltoid, 5-10 mm. long, the median oblong-ovate to broadly lanceolate, 12-27 mm. long, 5-8 mm. wide; sori in 2 series on the pinnae, between the costule and margin; indusia concealed among the sporangia. (Description based upon European specimens.) Alpine slopes.

Honshu (Mount Kitadake in Kai Prov.); very rare. Sakhalin, n. Kuriles, Kamchatka, Himalayas to Europe, and N. America.