7. Fissidens ceylonensis Dozy & Molk. 锡兰凤尾藓 xi-lan feng-wei xian
Ann. Sci. Nat., Bot., sér. 3, 2: 304. 1844. Type. Sri Lanka (Ceylon): König s.n.
Fissidens intromarginatulus Bartr., Rev. Bryol. Lichénol. 23: 242. 1954.
Plants small, yellowish green, gregarious, with fertile and sterile stems mixed in the same patch.
Leafy stems simple or branched, 2.3–5.0 mm long, 1.4–1.5 mm wide; axillary hyaline nodules not or only weakly differentiated; central strand not differentiated.
Leaves in 7–20 pairs, the lowest leaves small, loosely arranged, the remainder much larger, more or less densely arranged, almost of constant size; middle to upper leaves oblong-lanceolate, 0.2–0.8 mm × 0.2–0.3 mm, acute to broadly acute at apex; base of dorsal laminae of fertile leaves usually wedge-shaped, rounded to wedge-shaped in sterile ones; vaginant laminae
3¤5–
2¤3 the leaf length, equal to slightly unequal; costa light yellow, percurrent to slightly excurrent, with protruding rhombic cells; margins nearly entire; cells of apical and dorsal laminae quadrate to rounded-hexagonal, 7–8 µm long, obscure, pluripapillose, thin-walled; cells of vaginant laminae similar to, but larger than, those of apical and dorsal laminae, smooth and with thick walls toward the base near costa; limbidia usually found only on lower half of vaginant laminae of upper and perichaetial leaves, composed of 2–6 rows of cells, 1 cell thick, becoming shorter and the outermost layer changing into a row of quadrate to rectangular, papillose cells; limbidia of sterile stem leaves often weak or lacking.
Autoicous.
Male inflorescences terminal on main stems, rarely on short lateral branches.
Archegonia 250–260 µm long.
Perichaetial leaves differentiated, lanceolate; vaginant laminae with upper parts open to costa and with stronger limbidia.
Setae 2.0–2.5 mm long, smooth, geniculate at base; capsules symmetrical, erect; urns cylindrical, 0.4–0.5 mm long; exothecial cells quadrate, thin-walled with distinctly thickened corners; peristome teeth ca. 0.2 mm long, 32 µm wide at the base; opercula rostrate, ca. 0.4 mm long.
Calyptrae mitrate, ca. 0.3 mm long.
Spores 11–12 µm in diameter.