19. Fissidens geminiflorus Dozy & Molk. 二形凤尾藓 er-xing feng-wei xian
Pl. Jungh. 316. 1854. Type. Indonesia: Java.
Fissidens geminiflorus var. nagasakinus (Besch.) Iwats., J. Hattori Bot. Lab. 32: 272. 1969. Fissidens nagasakinus Besch., J. Bot. (Morat) 12: 292. 1898.
Fissidens irroratus Card., Beih. Bot. Centralbl. 19(2): 99. f. 5. 1905. Type. China: Taiwan, Kushaku, 6 VI 1903, U. Faurie 124 (isotype H-BR).
Plants medium-sized to rather large, green to dark green. Leafy stems prostrate, simple or branched, 8–42 mm long, 2.7–3.1 mm wide; axillary hyaline nodules often slightly differentiated; central strand not differentiated. Leaves in 16–52 pairs, usually loosely arranged, crisped when dry; lower leaves often decayed or fragile; middle and upper leaves lanceolate to narrowly lanceolate, 1.8–2.5 mm × 0.3–0.4 mm, acute at apex; base of dorsal laminae wedge-shaped, rarely rounded, clearly decurrent; vaginant laminae 1/2 –3/5 the leaf length, equal or slightly unequal; costa stout, percurrent, a row of cells at both sides of costa often enlarged, irregularly quadrate to rectangular, smooth, more or less pellucid; margins serrulate; cells of apical and dorsal laminae quadrate to rounded-hexagonal, 7–13 µm long, moderately thick-walled, mammillose, obscure; cells of vaginant laminae similar to those of apical and dorsal laminae, but larger, less mammillose and with thicker walls; in cross section laminal cells one cell thick, except near costa. Dioicous. Female inflorescences bud-like, axillary. Perichaetial leaves well differentiated. Archegonia 284–355 µm long. Male inflorescences and sporophytes unknown.