4. Barbula dixoniana (P.-C. Chen) Redfearn & B. C. Tan 狄氏扭口藓 di-shi niu-kou xian
Trop. Bryol. 10: 66. 1995. Hydrogonium dixonianum P.-C. Chen, Hedwigia 80: 250, 49 f. 3–6. 1941. Barbula inflexa Dix., Symb. Sin., Nachtr. Bericht. 19. 1929, hom. illeg. Type. China: Sichuan (Setschwan), Xi-chang Co. (Ningyüen), Handel-Mazzetti 1617 (holotype H).
Barbula subpellucida auct. non Mitt., J. Proc. Linn. Soc., Bot., Suppl. 1: 35. 1859.
Plants small, soft, in loose tufts. Leaves appressed or contorted when dry, erect-spreading when moist, ovate-lanceolate to oblong-triangular, rounded obtuse or acute; margins entire, often recurved in lower ½ –2¤3 of the leaf length; costa stout, percurrent or ending just below apex; upper leaf cells quadrate to hexagonal, rather thin-walled, obscure, multi-papillose with C-shaped papillae; basal cells usually differentiated, irregularly short-rectangular, smooth, hyaline. Gemmae often present, filiform, in leaf axils. Dioicous. Perichaetial leaves differentiated, often sheathing at base.