Distichium Moss

Plants of Distichium capillaceum form dense, rather silky tufts and the slender, spreading, distichous leaves with shiny, whitish, oblong, sheathing bases are characteristic. This is a taller species than D. inclinatum, with plants less crowded, capsules erect-symmetrical and cylindric, and spores smaller. In more northerly or alpine regions with more severe climatic conditions, the plants are often shorter, more compact, and have shorter leaves.

Plants slender, small to medium-sized, 2–8 cm high, bright green or yellowish green, shiny, in dense tufts. Stems erect, rarely branched, radiculose below. Leaves crowded, distichous, 3–5 mm long, abruptly narrowed from an erect, oblong-lanceolate, sheathing base to a long, setaceous apex, with acumina about 1–3 times as long as the sheathing base; margins plane, smooth at the sheathing base, papillose in the subula; costa stout, almost filling the entire subula; upper leaf cells irregularly hexagonal, 5–12 µm × 4–5 µm, moderately thick-walled; lower and basal cells becoming elongate, linear-rectangular, 40–70 µm × 2.5–5.0 µm, rather thin-walled. Autoicous or dioicous. Perichaetial leaves similar to the upper stem leaves. Setae straight, reddish brown, 1.0–1.5 cm long; capsules erect, symmetric, oblong-ovoid to cylindric, 1.4–2.1 mm × 0.4–0.6 mm; opercula shortly conic-rostrate; annuli differentiated, in 1–2 rows of large, thick-walled cells; peristome teeth short-lanceolate, 0.10–0.15 mm long, divided nearly to the base, reddish brown or pale yellow, papillose above, obliquely striolate below. Spores 13–24 µm in diameter, yellowish brown, coarsely papillose.

Stems to ca. 6 cm, occasionally longer. Sexual condition paro-icous. Seta to 2 cm, straight to somewhat flexuose, smooth, red or reddish brown, occasionally yellowish brown. Capsule brown, 1-2 mm, erect, cylindric to ovoid-cylindric, straight to weakly arcuate, becoming ± wrinkled when dry; operculum to 0.5 mm; peristome teeth evenly spaced, lanceolate, divided nearly to the base into 2(-3) filaments, smooth to papillose or sometimes ± striolate. Spores densely and finely papillose, 15-25 µm.

Distribution: nearly worldwide.

Habitat: on calcareous soil or rocks, or on humic and sandy soil.

? Distichium brevifolium C. Müll., Nuovo Giorn. Bot. Ital., n.s. 3: 91. 1896. Syn. nov. Type. China: Xizang (Tibet), J. Thomson 32 (holotype B, probably destroyed). Distichium papillosum C. Müll., Nuovo Giorn. Bot. Ital., n.s. 3: 90. 1896. ? Distichium trachyphyllum C. Müll., Nuovo Giorn. Bot. Ital., n.s. 3: 90. 1896. Type. China: Xizang (Tibet), J. Thomson 33 (holotype B, probably destroyed).

Cynontodium capillaceum Hedwig, Sp. Musc. Frond., 57. 1801

Distichium capillaceum is a species of moss belonging to the family Ditrichaceae.

It has cosmopolitan distribution.