短颈藓科 duan jing xian ke
by Wang Mei-zhi, Wu Peng-cheng, Si He, and Zacharia L. K. Magombo
Plants usually small, sometimes larger, perennial, dark green, in loose clumps or in scattered tufts. Protonemata often not persistent, with thalloid structure and funnel-shaped appendages. Stems erect, short, simple or occasionally branched, with dense, papillose rhizoids at base; in cross section central strand mostly absent. Leaves often strongly crisped and enrolled, sometimes weakly curled, straight when dry, erect-spreading when moist, larger and longer distally; lower leaves narrowly lingulate to linear or linear-spathulate, rounded obtuse, acute, apiculate or mucronate at apex; margins entire; costae stout, strong, often disappearing in the acumen, leaf cells often bistratose to multistratose in the upper part of the leaves, rounded quadrate or rounded hexagonal to slightly oblate, thick-walled, mammillose or papillose on both sides, rarely smooth, lower leaf cells unistratose, rectangular, smooth, hyaline, thin-walled; upper leaves similar to perichaetial leaves, larger, erect, ovate-lanceolate to oblong-lanceolate, sometimes slenderly lanceolate, often laciniate at the apex, costa excurrent. Axillary hairs filamentous, collared. Autoicous or dioicous. Perichaetia terminal. Perichaetial leaves longer or shorter than vegetative leaves, lanceolate, awn excurrent, smooth or papillose. Setae very short, pale; capsules immersed, obliquely ovoid-conic, asymmetric, smooth, neck not differentiated; stomata present at mouth or at base of capsules, superficial or immersed; annuli differentiated, deciduous or persistent; opercula small, conic; peristome double; exostome teeth rudimentary or lacking; endostome well developed, with 16-pleated segments, white, membrane-like, densely papillose. Calyptrae cucullate, conic or campanulate, small, not covering the entire opercula, smooth. Spores small, spherical, yellowish, smooth or minutely papillose.