Acianthus saxatilis is a species of flowering plant in the orchidfamily Orchidaceae and is endemic to Queensland. It is a terrestrialherb with a single, relatively large, heart-shaped leaf and usually up to 5 translucent greenish-brown to greenish-yellow flowers.
Description
Acianthus saxatilis is a glabrous, terrestrial, tuberous herb that grows in small colonies. It has an erect stem 40–90 cm (16–35 in) tall and a single heart-shaped leaf 38–70 mm (1.5–2.8 in) long and 20–90 mm (0.79–3.54 in) wide. The leaf is pale green on the upper surface and reddish-green to greenish-purple on the lower side. There are usually up to 5 light green flowers 10–13 mm (0.39–0.51 in) long and 5–7 mm (0.20–0.28 in) wide on a slender raceme 30–80 mm (1.2–3.1 in) tall with prominent heart-shaped, leaf-like floral bracts 4–12 mm (0.16–0.47 in) long at the base. The dorsalsepal is egg-shaped, 8–12 mm (0.31–0.47 in) long, 4.5–8 mm (0.18–0.31 in) wide and forms a hood over the column. The lateral sepals are 9.5–14 mm (0.37–0.55 in) long and 3.0–3.5 mm (0.12–0.14 in) wide, the petals lance-shaped and curved, 7–9 mm (0.28–0.35 in) long and about 3 mm (0.12 in) wide. The labellum is 8.5–10 mm (0.33–0.39 in) long and 4.5–5.0 mm (0.18–0.20 in) wide and light greenish-brown to greenish-yellow with light brown edges, the callus with a narrow brownish band in the centre. Flowering occurs from February to May.[2][3]
This species is distinguished from others in the genus by its relatively large leaf, large floral bracts and greenish and brown flowers[2]
