Pterostylis revoluta

Pterostylis revoluta is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of between three and seven greyish to bluish, egg-shaped leaves. Each leaf in the rosette is 10–30 mm long and 4–12 mm wide. Flowering plants have a single flower 20–25 mm long, 9–12 mm wide and which lean forwards slightly. The flower is borne on a flowering stem 100–150 mm high with between three and five leaves wrapped around the stem. The flowers are pale green and white with a brown tinge. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal curves forward and downward with a thread-like tip 4–8 mm long. The lateral sepals are held closely against the galea, have an erect, curved thread-like tip 20–25 mm long and a narrow V-shaped sinus between their bases. The labellum is 14–17 mm long, about 3 mm wide, curved, pointed and extends for about half its length above the sinus. Flowering occurs from February to June.[2][3]

Pterostylis revoluta was first formally described in 1810 by Robert Brown and the description was published in the Prodromus Florae Novae Hollandiae et Insulae Van Diemen.[1][4] The specific epithet (revoluta) is a Latin word meaning "turned over" or "rolled back".[5]

The autumn greenhood grows on sheltered slopes in forest and in coastal scrub in coastal and near-coastal area from south-east Queensland to Nowra in New South Wales and as far inland as Cessnock.[2][3]