珠藓科   zhu xian ke

by Zang Mu and Si He

 

 

Plants small to rather large, in loose or dense tufts or compact. Stems erect, simple or irregularly branched, densely foliate, often radiculose or tomentose below; central strand present or absent. Leaves appressed, imbricate to widely spreading or squarrose, ovate-lanceolate to lanceolate or linear, usually not decurrent at base, often sheathing at base, rarely plicate; margins not bordered, serrate in the upper margins, often dentate at back; costae single, strong, ending below the apex or excurrent, in cross section with only dorsal stereid bands; leaf cells rounded-quadrate, rectangular or rarely narrowly rectangular, usually thick-walled, not porose, papillose or mammillose at or near 1 or both ends, sometimes centrally papillose, rarely smooth; basal cells enlarged, hyaline, usually smooth, alar cells rarely differentiated. Autoicous or dioicous. Sporophytes terminal, occasionally lateral due to annual innovations of new branches. Perichaetial leaves large, similar to vegetative leaves. Setae solitary, rarely 2–5-clustered, elongate; capsules erect or inclined, rarely pendulous, usually spherical, furrowed or not furrowed; sometimes neck developed; mouth oblique; stomata superficial, numerous; opercula small, shortly apiculate, rarely rostrate; annuli usually undeveloped; peristome double, rarely single or reduced; exostome teeth lanceolate, yellowish brown or reddish brown, smooth or papillose, usually not bordered, trabeculate on inner surface; endostome segments shorter, keeled, perforate; basal membrane ca. 1/4–1/2 the height of the teeth; cilia 1–3, not nodulose, reduced or rudimentary. Calyptrae small, cucullate, smooth. Spores large, spherical, ellipsoidal or kidney-shaped, papillose.

1. Stems in cross section triangular; leaf cells smooth........................................................................ 6. Plagiopus

1. Stems in cross section rounded; leaf cells papillose............................................................................................ 2

2. Stems without subfloral branches; outer cortical cells of stem cross section small, thick-walled.............. 3

2. Stems with whorled subfloral branches; outer cortical cells of stem cross section large, lax, thin-walled 4

3. Leaves closely appressed, not sheathing at base; capsules not furrowed when dry.......................... 1. Anacolia

3. Leaves not appressed, more or less ascendant, sheathing at base; capsules furrowed when dry........ 2. Bartramia

4. Capsules elongate-ovoid, with a long, prominent apophysis............................................ 4. Fleischerobryum

4. Capsules more or less spherical, with a short apophysis.................................................................................. 5

5. Leaves patent-spreading or squarrose, distinctly longitudinally plicate at base; leaf cells linear.......... 3. Breutelia

5. Leaves appressed or ascending, not spreading, not plicate at base; leaf cells rectangular............ 5. Philonotis