1. Microdus brasiliensis (Duby) Thér. 梨蒴小毛藓 li-shuo xiao mao xian
Bull. Herb. Boissier sér. 2, 7: 278. 1907. Weissia brasiliensis Duby, Mém. Soc. Phys. Geneve 7: 412. pl. 4. 1836. Dicranella brasiliensis (Duby) Bartr., Philippine J. Sci. 68: 34. 1939. Type. Brazil.
Microdus pomiformis (Griff.) Besch. in Pairs, Index Bryol. 805. 1897. Didymodon pomiformis Griff., Calcutta J. Nat. Hist. 2: 508. 1842.
Plants very small, up to 5(–7) mm high, yellowish green or yellowish, in loose tufts. Stems erect, simple or sparsely branched. Leaves up to 2 mm long, erect or falcate, flexuose or slightly crispate when dry, lower leaves smaller, upper ones larger, lanceolate from a narrowly ovate base, gradually narrowed to a subulate apex; margins plane or slightly incurved; costa thick, occupying 1/4–1/3 the leaf base width, brownish, excurrent; cells elongate-rectangular to narrowly rhomboidal, 4–5:1 near the base, shorter toward the apex; alar cells not differentiated. Perichaetial leaves much longer than stem leaves. Setae 5–7 mm long, straight, flexuose when dry, yellowish; capsules small, ovoid to subglobose, 0.6–0.7 mm × 0.4–0.5 mm, smooth; opercula long-rostrate, longer or as long as the urns; peristome teeth short, very irregularly cleft, perforate, finely papillose. Spores 14–18 µm in diameter, brownish, finely papillose.