long-tongued shell orchid

Pterostylis dolichochila is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of four to ten egg-shaped leaves. Each leaf is 4–12 mm long and 3–8 mm wide. Flowering plants have a single flower 20–25 mm long and 7–9 mm wide borne on a spike 50–150 mm high with three or four stem leaves wrapped around it. The flowers are green and white with reddish-brown stripes. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal curves forward with sharp point or a thread-like tip 1–2 mm long. The lateral sepals are held closely against the galea, have an erect, thread-like tip 15–20 mm long and a broad, flat sinus between their bases. The labellum is 13–15 mm long, about 4 mm wide, brown, blunt, and curved and protrudes above the sinus. Flowering occurs from April to August.

The long-tongued shell orchid grows on calcareous sand and limestone, sometimes forming large colonies, in mallee in the south-east of South Australia and the Little Desert and Big Desert areas of Victoria.

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