"Oni-hikage-warabi" (Diplazium nipponicum) belongs to the Woodsiaceae family. It is an evergreen or summer-green fern that is native from Honshu to Shikoku and Kyushu, as well as Zhejiang in China. This fern grows in wettish mountain forests, and it can reach 70-120 cm in height. The rhizome is thick and creeping long. The fertile fronds are biternate to triternate compound, and about 1.3 m long. The blackish-brown to brownish-red, narrow lanceolate scales are borne at the base of petioles. The sponrangia bands are linear and arrnaged near the rachises.