Pterostylis nana, commonly known as the dwarf snail orchid, is a species of orchidendemic to Australia. It has a rosette of leaves at it base and a single narrow, bright green and white flower with a small labellum. There is uncertainty about its classification - some sources include South Australia and Western Australia in its range.
Description
Pterostylis nana is a terrestrial, perennial, deciduous, herb with an underground tuber and a rosette of egg-shaped to heart-shaped leaves, each leaf 5–20 mm long and 3–10 mm wide. A single bright green and white flower, 10–15 mm long and 4–5 mm wide is borne on a stalk 50–150 mm high. The dorsal sepal is erect, more or less flat on top and fused to the petals forming a hood or "galea" over the column. The lateral sepals are erect, in close contact with the galea and taper to a thread-like tip about 20 mm long. The sinus between the lateral sepals is more or less flat and has a dark green central area. The labellum is 3–5 mm long, about 2 mm wide, straight, blunt and hidden inside the flower. Flowering occurs from July to October.[2][3][4]
The dwarf snail orchid grows in a range of habitats from coastal heath to forest, mostly in sheltered sites. It occurs in New South Wales south from Taree and is widespread in Victoria and Tasmania[2][3][4][6]
^ abJones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. pp. 298–299. ISBN978-1877069123.
^ abJones, David L. "Pterostylis nana". Royal Botanic Garden Sydney: plantnet. Retrieved 28 April 2017.
^ abcJeanes, Jeff. "Pterostylis nana". Royal Botanic Garden, Melbourne: vicflora. Retrieved 22 May 2017.
^"Pterostylis nana". State Herbarium of South Australia. Retrieved 22 May 2017.
^Jones, David L. (1998). "Contributions to Tasmanian Orchidology". Australian Orchid Research. 3: 146–147.