Swamp Sun Orchid

Thelymitra cyanea is a tuberous, perennial herb with a single erect, fleshy, channelled, linear leaf 150–250 mm (6–10 in) long and 5–7 mm (0.2–0.3 in) wide. Up to five bright blue flowers with darker veins, 20–30 mm (0.8–1 in) wide are borne on a flowering stem 200–400 mm (8–20 in) tall. There are usually and two bracts on the flowering stem. The sepals and petals are 12–16 mm (0.5–0.6 in) long and 8–10 mm (0.3–0.4 in) wide but the lavellum (the lowest petal) is larger than the other petals and sepals. The column is white to pale blue, 4–6 mm (0.16–0.24 in) long and about 3 mm (0.12 in) wide. The side arms of the column are yellow, with a twisted or toothed tip. The flowers are often self-pollinating and open on warm sunny days. Flowering occurs from November to March.

Thelymitra cyanea is widespread and often common in many parts of south-eastern Australia and New Zealand. It grows in damp to wet boggy places, mainly in montane and subalpine habitats. In New Zealand it is widespread on the North, South and Chatham Islands. In New South Wales it is found on the tablelands south from Ebor, in south-eastern Victoria and in Tasmania. In South Australia it is restricted to near Mount Compass.