25. Fissidens hyalinus Hook. & Wils. in Hook. 透明凤尾藓 tou-ming feng-wei xian
J. Bot. (Hooker) 3: 89, f. 2. 1840. Type. U.S.A.: Ohio, T. G. Lea s.n. (isotype NY).
Plants very small, delicate, pale green, loosely gregarious.
Leafy stems simple, 1.2–3.2 mm long, 0.8–3.0 mm wide; axillary hyaline nodules not differentiated; central strand lacking.
Leaves in 2–5 pairs, densely arranged, upper leaves much larger than lower leaves, oblong-lanceolate to oblong-ovate, 0.6–1.4 mm × 0.2–0.6 mm, acute at the apex; base of dorsal laminae rounded, vaginal laminae nearly
1¤2 the leaf length; costa absent; margins plane, entire, bordered throughout by 1–2 rows of elongate cells; cells of apical laminae quadrate to irregularly hexagonal, 35–87 µm long, smooth, thin-walled; cells of vaginant laminae similar to those of apical laminae.
Sporophytes unknown.