Cyptodon muelleri

On rocks, and roots and tree and shrub bases subject to inundation. Stems 4–8 cm long, erect or pendulous, pinnately branched, black, with brown rhizoids restricted to base. Leaves erect-spreading when moist, erect and appressed when dry, ovate to nearly elliptic, 0.9–2 mm long, 0.5–1.2 mm wide, sometimes slightly plicate, concave when dry; apices obtuse or broadly acute; costae subpercurrent; margins entire or sometimes irregularly serrulate toward apices, plane or reflexed near base, without a border; laminal cells mostly rhomboid, more quadrate near margin, (5–) 10–25 μm long, 7–13 μm wide, smooth; basal cells nearly linear, c. 50–80 μm long, 7–10 μm wide, smooth; alar cells indistinct. Perichaetial leaves oblong to elliptic, 1.6–2.3 mm long, 0.5–0.8 mm wide, with long-excurrent costae. Setae to c. 0.25 mm long. Capsules erect, broadly cylindric, straight, 1–1.5 mm long, yellow-brown. Opercula rostrate from flat base, 0.2–0.4 mm long.