7. Hydrogonium javanicum (Dozy & Molk.) Hilp. 爪哇石灰藓 zhao-wa shi-hui xian
Beih. Bot. Centralbl. 50(2): 632. 1933. Barbula javanica Dozy & Molk., Ann. Sci. Nat., Bot., sér. 3, 2: 300. 1844. Type. Indonesia: Java.
Hydrogonium consanguineum (Thwait. & Mitt.) Hilp., Beih. Bot. Centralbl. 50(2): 626. 1933. Tortula consanguinea Thwait. & Mitt., J. Linn. Soc., Bot. 13: 300. 1873.
Hydrogonium javanicum var. convolutifolium (Dix.) P.-C. Chen, Hedwigia 80: 244. 1941. Barbula convolutifolia Dix., Hong Kong Naturalist, Suppl. 2: 10. 1933. Type. China: Hong Kong, Herklots 249b.
Plants small, 5–10 mm high, yellowish green, in dense tufts. Stems erect, short, usually branched. Leaves appressed or imbricate when dry, erect-spreading when moist, ovate-ligulate; margins entire, plane in the lower half, serrulate, somewhat concave or cucullate in the upper half; costa stout, percurrent; upper leaf cells irregularly quadrate to hexagonal, thick-walled, mostly smooth, occasionally mammillose.