1. Rhynchostegiella japonica Dixon & Thér. 日本细喙藓 ri ben xi hui xian
Rev. Bryol., n.s., 4: 167. 1932. Type: Japan. Honshu, Pref. Kyoto, Takahashi s.n.
Plants slender, dark green, in loose mats. Stems prostrate, to 2–4 cm long, irregularly or subpinnately branched, loosely foliate, with complanate branches. Stem and branch leaves similar, erect-spreading, ovate-lanceolate to narrowly ovate-lanceolate or elliptical-lanceolate, 1.3–2.2 mm × 0.5–0.7 mm, concave, somewhat asymmetric, shortly acuminate at apex, not plicate; margins serrulate above, entire below; costae mostly reaching just above 1/2 the leaf length, slender, not projecting at tips; median leaf cells linear-rhomboidal, 80–96 µm × 7–8 µm, smooth; alar cells lax, short, inflated, shortly rectangular. Setae smooth; other sporophytic features not seen.