玉山黑藓

Plants slender, brown to dark brown, up to 2 cm high, in dense tufts. Stems erect or ascending, single or forked. Leaves 0.6–0.7 mm × 0.30–0.35 mm, imbricate, erect-spreading when dry, distinctly concave, narrowly lanceolate from an ovate base, acuminate; margins entire, incurved throughout on both sides; upper and median laminal cells quadrate to short-rectangular, 6–8(–10) µm × 5–6 µm, irregularly thick-walled, distinctly papillose; basal cells near margins with papillae similar to the median cells; central basal cells elongate, 20–30 µm × 3–5 µm, irregularly thick-walled, more or less pitted. Dioicous. Perichaetial leaves oblong-lingulate, acute, about 2 mm long. Capsules ovate-oblong, upper half of capsules dark-brown, split into 4 or 5 valves when mature, lower half yellowish, never splitting. Spores yellowish brown, 17–22 µm in diameter, finely papillose. (Only male plants were seen. Sporophyte characters were adopted from Noguchi 1936.)

Type. China: Taiwan, Tainan, Tataka, Niitatkasita, Noguchi 6515.

Chinese specimen examined: TAIWAN: Tainan, Ozaki 119 (NICH).

Habitat: on rocks in mountain areas; Distribution: known only from Taiwan.

Andreaea morrisonensis can be distinguished by the following characters: 1) only the upper half of capsules splitting into 4 or 5 valves when mature; 2) the leaves loosely imbricate when dry, lanceolate from an ovate base with acuminate apex; 3) the margins incurved throughout on both sides; and 4) laminal cells papillose. This species is similar to Andreaea wangiana in having the dehiscence of capsules only in the upper half, but it differs by the characters 2–4 listed above. The present species is related to A. mutabilis in having similar leaf shape and cells, but it is different from the latter by capsule dehiscence. Andreaea mutabilis has the capsules split from the tip to near the base.

Illustrations: Pl. 11, figs. 1–9.