Pterostylis scabra, commonly known as the green-veined shell orchid, is a species of orchid endemic to the south-west of Western Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a white flower with green and pale brownish-fawn stripes and a long, curved protruding labellum. It is found in inland areas between Kalbarri and Esperance.
Pterostylis scabra is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of leaves lying flat on the ground, each leaf 10–40 mm (0.4–2 in) long and 2–3 mm (0.08–0.1 in) wide. Flowering plants have a single flower 30–40 mm (1–2 in) long and 10–12 mm (0.4–0.5 in) wide borne on a flowering stem 60–180 mm (2–7 in) high. The flowers are white with green and pale brownish-fawn stripes. The dorsal sepal and petals are fused, forming a hood or "galea" over the column, the dorsal sepal curving forward with a short pointed tip. The lateral sepals are erect with a small gap between them and the galea and have thread-like ends 30–35 mm (1.2–1.4 in) long. The labellum is long, narrow and down-curved, protruding prominently above the sinus between the lateral sepals. Flowering occurs from May to August.[3][4][5]
Pterostylis scabra was first formally described in 1840 by John Lindley and the description was published in the A Sketch of the Vegetation of the Swan River Colony.[1][6] The specific epithet (scabra) is a Latin word meaning "rough", "scurfy" or "scabby",[7] referring to the rough surface of the labellum.[3]
The green-veined shell orchid is found in inland areas between Kalbarri and Esperance in the Avon Wheatbelt, Esperance Plains, Geraldton Sandplains, Jarrah Forest and Mallee biogeographic regions.[3][4][8]
Pterostylis scabra is classified as "not threatened" by the Western Australian Government Department of Parks and Wildlife.[8] It usually grows in moist, shaded areas, often near temporary streams but also grows in woodland and on granite outcrops.[3][4]
Pterostylis scabra, commonly known as the green-veined shell orchid, is a species of orchid endemic to the south-west of Western Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a white flower with green and pale brownish-fawn stripes and a long, curved protruding labellum. It is found in inland areas between Kalbarri and Esperance.
