Braithwaitea sulcata

Stems projecting horizontally from tree trunks, branches and occasionally rocks. Stipes to 6.5 (–8) cm long, without leaves near base, black. Fronds ovate-oblong, to 8 (–11) cm long, pinnately to bipinnately branched. Stipe leaves triangular- to ovate-oblong, 2.5–4.5 mm long, 1–1.8 mm wide, concave; apices acute to gradually long-acuminate; costae distinct to very faint, percurrent to shortly excurrent; margins remotely and minutely crenulated to serrulate, plane; cells linear, 45–115 μm long, 3.5–6 μm wide, smooth to weakly prorate; alar cells quadrate to rectangular, forming a small elongate group. Branch leaves erecto-patent when moist, imbricate and often irregularly longitudinally undulate when dry, ovate to ovate-oblong, 1.5–2 mm long, 0.6–0.9 mm wide, concave; apices somewhat obtuse to truncate or emarginate; costae strong, excurrent as a short, often recurved mucro; margins serrate to dentate near apex, recurved at apex; cells linear, 25–80 μm long, 4.5–5 μm wide, smooth to weakly prorate. Setae (7–) 10–15 (–18) mm long, orange to pale brownish, reddish or dark brown, smooth. Capsules erect or suberect, cylindric, straight or almost so, striate to angular or deeply sulcate, occasionally almost smooth, (3–) 3.5–5 (–5.5) mm long. Opercula conic, with a blunt apex, c. 0.9–2 mm long.