Acianthus collinus

Flowering plant 6–15 cm tall. Leaf cordate, thin, 1.5–3.5 cm long, 1.5–3 cm wide, green above, reddish-purple beneath, entire or sometimes shallowly lobed. Flowers 2–9, translucent pink with a dark purple-red labellum; pedicel (including ovary) 5–8 mm long, subtended by small bract; dorsal sepal ovate, cucullate, 6–8 mm long, including apical point 1–2 mm long, usually slightly warty on upper surface; lateral sepals projected obliquely forwards, usually crossed, linear to linear-lanceolate, 7–11 mm long, apical point 1–2 mm long; petals spreading widely, linear-ovate to lanceolate, 3–5 mm long. Labellum on short claw, slightly decurved distally, cordate, 5–6 mm long, 3–4 mm wide, distal margins recurved to revolute, finely toothed, apex with short point; callus thick, fleshy, densely tuberculate towards the apex. Column incurved, almost terete, not winged. Flowers Jun.–Aug.