舌叶藓

Merceya ligulata (Spruce) Schimp., Syn. Musc. Eur. (ed 2) 2: 852. 1876. Merceya thermalis Fleisch. ex Broth., Nat. Pflanzenfam. (ed. 2) 11: 247. 1925, nom. illeg. Merceya thermalis var. compacta Fleisch. in P.-C. Chen, Hedwigia 80: 271. 1941, nom. nud.

Plants medium-sized to rather large, to 5 cm high, soft, yellowish green to dark brown, in dense tufts. Stems erect, fragile, simple or branched, radiculose at the base. Leaves moderately contorted-curved when dry, spreading when moist, 2–3(–4) mm long, ligulate to elliptic-lanceolate from a narrowed base, obtuse to rounded apiculate at the apex; margins plane or somewhat recurved below, subentire to crenulate above, sometimes bordered by several rows of thicker-walled cells; costa slender, subpercurrent, ending a few cells below the apex; upper leaf cells quadrate to irregularly hexagonal, 5–8 µm in diameter, moderately thick-walled, smooth; basal cells laxly rectangular, somewhat enlarged, thin-walled, smooth. Setae ca. 5 mm long; capsules oblong-ovoid; opercula conic-rostrate, with a short erect beak.

Type. Pyrenees: Spruce s.n.

Chinese specimens examined: ANHUI: Huang Shan (Mt.), W.-F. Zheng 128, 191 (HKAS). GUANGXI: Luo-cheng Co., R.-G. Lung 89032 (HKAS). GUIZHOU: Shan-an Co., Z.-W. Li 425 (PE). LIAONING: Dan-dong City, Feng-huang Shan (Mt.), X.-Y. Jia 880755 (HKAS). SICHUAN: Wen-chuan Co., J.-X. Luo 3611 (PE). TAIWAN: Miao-li Co., Shevock 14373 (MO); Nan-tou Co., C.-C. Chuang 6153 (MO); Tai-mo Shan (Mt.), Iwatsuki 51 (NICH). YUNNAN: Da-li Co., Handel-Mazzetti 8588 (H, MO); Gong-shan Co., Du-long-jiang, D.-C. Zhang 3274 (HKAS). ZHEJIANG: western Tian-mu Shan (Mt.), M. Zang 202 (HKAS).

Habitat: on wet rocks in shade or soil walls; Distribution: China, Japan, India, Indonesia, the Philippines, northern Africa, Europe, and North and South America.

Illustrations: C. Gao (ed.) 1996 (Pl. 77, figs. 3–6, as Merceya ligulata).