short-creeping; fronds tufted; stipes 20-40 cm. long, thinly scaly in lower part, 4-5 mm. across near base; scales pale brown, membranous, broadly lanceolate, entire; blades thinly herbaceous, broadly lanceolate to narrowly ovate, 35-50 cm. long, 17-22 cm. wide, slightly narrowed at baseļ¼bipinnati- parted, vivid green, paler beneath; pinnae about 10 pairs, subopposite or subalternate, lanceolate, 2-3.5 cm. wide, long- acuminate, sessile, short-hairy on costas above and on underside while young or glabrous, the rachis prominendy winged; pinnules rather many, oblong to oblong-ovate, 1-1.5 cm. long, 5-7 mm. wide, obtuse, lobed to coarsely toothed; sori 4-12, nearly median; indusia 1-2 mm. long, slightly arcuate, often athyrioid, minutely ciliolate.
Honshu (centr. distr.), Kyushu (n. distr.); rare. Korea, Manchuria, and e. Siberia.
var. kiyozumianum (Kurata) Tagawa. Stipes shorter, 9-16 cm. long; scales more abundant on stipes and rachis. Honshu (Mount Kiyozumi in Awa Prov.).