About Calochilus robertsonii Benth.
Calochilus robertsonii Benth. is a terrestrial, perennial, deciduous herb that grows from an underground tuber. It produces a single fleshy, dark green, linear to lance-shaped leaf, which measures 150–400 mm (6–20 in) long and 8–12 mm (0.3–0.5 in) wide. Unlike some other species in the Calochilus genus, the leaf is fully developed when the plant flowers. Between one and nine green to brown flowers that have reddish or purplish stripes are carried on a flowering stem 150–450 mm (6–20 in) tall. The dorsal sepal is 12–15 mm (0.5–0.6 in) long and 8–11 mm (0.3–0.4 in) wide, while the lateral sepals are a similar length but narrower than the dorsal sepal. The petals are 7–9 mm (0.3–0.4 in) long and 5–6 mm (0.20–0.24 in) wide. The labellum is flat, 20–35 mm (0.8–1 in) long and 6–8 mm (0.24–0.31 in) wide, with short, purplish calli located near its base. The middle section of the labellum has coarse, mauve, purple or bronze-coloured hairs that grow up to 5 mm (0.2 in) long, and the tip of the labellum has a glandular "tail" that is 5–10 mm (0.2–0.4 in) long and around 1 mm (0.04 in) wide. The column has two purple false "eyes" connected by a distinct raised ridge. Flowering of this species occurs from August to early December. This species is commonly called the purplish beard orchid. It is widespread and common in eastern Australia, where it grows in a variety of habitats ranging from heath to forest and scrubland, from the coast up to mountain regions. In Australia, it occurs in Queensland south from Gympie, in coastal districts and inland as far as Condobolin in New South Wales, throughout most of Victoria, and also in South Australia, the Australian Capital Territory, and Tasmania. In New Zealand, C. robertsonii only occurs naturally on the North Island; only a single specimen was ever collected from the northern tip of the South Island, in 1965.
