Frullania aterrima

Epiphytic, reddish-brown. Stems frequently pinnately branched. Mid stem and branch lateral leaf lobes oblong-ovate, 0.26–0.45 mm long, 0.2–0.35 mm wide, rounded to obtuse at apex, not angled away from substrate when moist, imbricate or contiguous; cells elliptic near base becoming quadrate toward margins, 6–20 µm long and 6–13 µm wide at margins, 10–20 µm long and 6–14 µm wide near centre, 17–30 µm long and 9–25 µm wide at base, evenly thick-walled, with trigones and occasional intermediate thickenings near basal centre. Lobule clavate, 0.15–0.18 mm tall, 0.06–0.1 mm wide, diverging at 30–50˚ from stem, rounded at apex; cells irregular, 10–25 µm long, 4–12 µm wide, with intermediate thickening and indistinct trigones throughout. Stylus filiform, c. 5 cells long and 2 cells wide. Underleaves widely obovate to orbicular in outline, bilobed 1/2–4/7 of length, with 1–3 teeth on each side, 0.13–0.18 mm long, 0.13–0.19 mm wide, flat; sinus acute; cells oblong to quadrate, 9–23 µm long, 7–13 µm wide, thick-walled throughout, with indistinct trigones mostly towards midline and base, without intermediate thickenings. Perianth pyriform, c. 1 mm long and 0.5 mm wide, 3-keeled, obtuse at apex with beak, smooth.