台湾阴地蕨 tai wan yin di jue

Sceptridium formosanum (Tagawa) Holub.

Rhizomes erect, cylindrical, ca. 2 cm, annually producing 1 or 2 fronds 15-60 cm tall. Sterile lamina: stalk (4-)13-35 cm, sparsely lanuginose; lamina subternate, tripinnate, deltoid-pentagonal, 8-35 × 8-40 cm, thickly herbaceous; pinnules broadly lanceolate, apex acute; ultimate segments elliptic, irregularly roughly serrate, apex obtuse or subacute; veins pinnate, free. Sporophore arising (2-)6-15 cm below top of common stipe (or near middle of common stipe); stalk 7-20 cm; lamina deltoid, 5-18 cm, bipinnate; sporangia globose, attached on both lateral sides of axes. Spore surface with dense papillae often uniting in reticulate pattern, with minute granules. 2n = 180.

Guangdong, Guangxi, Guizhou, Jiangxi, Taiwan, Yunnan [Himalaya, Japan].

Reviewer Ralf Knapp suggests that records of Botrychium japonicum and B. daucifolium from Taiwan might have been based on misidentifications of material of B. formosanum.