东亚小石藓

Hymenostomum exsertum (Broth.) Broth., Nat. Pflanzenfam. I(3): 386. 1902.

Plants small, 4–10 mm high, bright green to brownish green, in dense tufts. Stems erect, often irregularly branched. Leaves often crowded at stem tips, contorted-curved when dry, erecto-spreading when moist, narrowly lanceolate, sheathing at base, upper lamina often channeled, acuminate at apex; margins strongly incurved above the leaf base, crenulate by projecting papillae or serrulate near apex; costa rather stout, shortly excurrent, ending in sharply mucronate tips; upper leaf cells rounded-hexagonal, evenly thick-walled, papillose, with bifid or branched papillae; basal cells sharply differentiated, short-rectangular, sometimes forming a V-shaped leaf base, mostly thin-walled, smooth. Autoicous. Setae straight, 1–2 mm long, yellowish brown; capsules erect, oblong-elliptic, exserted.

Type. Japan: Kiushiu, Nagasaki, Wichura 1396.

Specimens examined: ANHUI: Qing-yang Co., Z.-L. Liu 30125 (HKAS, SHM); Tian-zhu Shan (Mt.), Z.-L. Liu 30223 (HKAS, SHM); Wu-hu City, Courtori 1112 (H), K.-H. Cai 2333 (HSNU). FUJIAN: Wuyi Shan (Mt.), P.-C. Chen 95 (PE), X.-J. Li 160 (HKAS); Zhang-zhou City, M. Zang 49 (HKAS). GUANGDONG: Ding-hu Shan (Mt.), H. Wu B267 (PE). GUANGXI: Tian-lin Co., C. Gao 2396 (HKAS, IFSBH). HAINAN: Ba-wang-ling (Mt.), C. Gao 3013 (HKAS, IFSBH). HEBEI: Wei Co., Y.-C. Zhao 87 (PE). HEILONGJIANG: Jing-bo-hu (Lake), C. Gao 9051 (HKAS, IFSBH). HUNAN: Sang-zhi Co., D.-L. Li 18326 (HKAS, SHM). JIANGSU: Nan-jing City, M. Zang 18827 (HKAS). JIANGXI: Jing-gang Shan (Mt.), D.-K. Li 17326 (HKAS, SHM); Lu Shan (Mt.), D.-K. Li 16966 (HKAS, SHM). JILIN: Chang-bai Shan (Mt.), C. Gao 15831 (HKAS). LIAONING: Kuan-dian Co., X.-L. Chen 1258 (HKAS, IFSBH). SHAANXI: Hu Co., M. Wang 346 (HKAS; Lin-tong Co., C. Gao 16039 (HKAS, IFSBH). SHANGHAI: Jin Shan (Mt.), D.-K. Li 959 (HKAS, SHM). SHANXI: Ning-wu Co., C. Gao 18540 (HKAS, IFSBH). SICHUAN: Mu-li Co., M.-Z. Wang 23767 (PE); Nan-chong City, J.-X. Luo 238 (PE); Nan-ping Co., S.-Y. Zheng 26 (HKAS); Wo-long Nature Reserve, J.-X. Luo 3525 (PE). TAIWAN: Tai-pei Co., Koponen 17968 (H, HKAS). XIZANG: Cha-yu Co., M.-Z. Wang 12563b (PE); Li-zhi Co., Lu-lang (Lunang), S.-K. Chen 391 (HKAS). Mi-lin Co., M. Zang 7460 (HKAS); Mo-tuo Co., Y.-G. Su 2174, 3644 (HKAS). YUNNAN: Gong-shan Co., M.-Z. Wang 11275b (PE); Kun-ming City, Koponen 37553 (H, HKAS); Li-jiang Co., X.-J. Li 81531 (HKAS); Teng-chong Co., X.-J. LI 80318 (HKAS). ZHEJIANG: Sui-chang Co., R.-L. Hong 288 (HSNU); Wen-zhou City, D.-K. Li 7374 (HKAS, SHM).

Habitat: on boulders, tree trunks, or rotten wood; also on rocks and soil near streams; Distribution: China, Japan, and India.

Illustrations: Pl. 135, figs. 5–7.