Korea Flora: Habit: Evergreen perennial herb; leaves fasciculate from thick rhizome.
Stipe: 20-40 cm long, densely scaly.
Scales: Reddish-brown, linear-lanceolate; margins entire; larger ones up to 1 cm long; some bullate; becoming narrower and shorter upwards, readily deciduous.
Blade: Oblong-ovate to triangular-ovate, 25-50 cm × 15-30 cm; bipinnate.
Pinnae: Lanceolate; long-acuminate.
Pinnules: When shallowly divided: oblong; apex rounded or truncate-rounded; margins slightly serrulate, When deeply divided: apex obtuse or acute; base auriculate on both sides; shortly stalked; margins shallowly to halfway pinnatifid
Sori: Arranged in 1-3 rows near costa or medial; indusium round-reniform with entire margins.
Habitat: Growing in evergreen forests of Jeju Island.
Note: Distinguished by its habitat in Jeju's evergreen forests and dimorphic pinnules (shallowly to deeply divided).

[Translated from Flora of Korea by T.B. Lee]