Ophioderma Blume.

Plants terrestrial, rarely epiphytic, generally small, erect, rarely large and pendulous. Rhizome erect, rarely creeping, short, glabrous or long hairy. Fronds often solitary, occasionally 2, rarely more; sterile lamina with stipe, usually simple, lanceolate, ovate, or ribbon-shaped, rarely dichotomously divided, with entire or wavy margin; midrib indistinct; veins reticulate; sporophore arising from base, near base, or middle part of sterile lamina, with long stalk. Sporangia embedded in 2 rows along margin of linear spike; spore surface irregularly reticulate, foveolate, or subsmooth.

About 28 species: mainly in the N Hemisphere; nine species (two endemic) in China.

(Authors: Liu Quanru (刘全儒); Norio Sahashi)