13. Didymodon perobtusus Broth. 细叶对齿藓 xi-ye dui-chi xian
Rev. Bryol., n. sér. 2: 1. 1928. Barbula perobtusa (Broth.) P.-C. Chen, Hedwigia 80: 194. 1941. Type. Mongolia: Kossogol, Novyn Chore, A. Elenkin s.n.
Didymodon rigidulus Hedw. var. perobtusus (Broth.) Redfearn & B. C. Tan, Trop. Bryol. 10: 66. 1995. Barbula rigidula (Hedw.) Mitt. var. perobtusa Broth., Symb. Sin. 4: 41. 1929. Type. China: Yunnan, between Nujiang and Lancangjiang, Handel-Mazzetti 8441 (holotype H).
Plants small, slender, ca. 5 mm high, yellowish green to somewhat dark green, in dense tufts. Stems erect, usually branched. Leaves imbricate, appressed when dry, erect-spreading when moist, broadly ovate at the base, abruptly narrowed to a short and blunt apex; margins entire, revolute; costa stout, subpercurrent; upper leaf cells quadrate, somewhat thick-walled, sparsely unipapillose or smooth; basal cells short-rectangular, smooth, hyaline.