Pterostylis erythroconcha, commonly known as the red shell orchid, is a species of orchid endemic to South 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 have a single flower with leaves on the flowering spike. This greenhood has a white and green flower with reddish brown markings and a long, fleshy, curved labellum.
| Red shell orchid | |
|---|---|
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Order: | Asparagales |
| Family: | Orchidaceae |
| Subfamily: | Orchidoideae |
| Tribe: | Cranichideae |
| Genus: | Pterostylis |
| Species: | P. erythroconcha
|
| Binomial name | |
| Pterostylis erythroconcha | |
| Synonyms[1] | |
|
Diplodium erythroconchum (M.A.Clem. & D.L.Jones) D.L.Jones & M.A.Clem. | |
Description
editPterostylis erythroconcha is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of between three and ten egg-shaped leaves. Each leaf is 60–150 mm (2–6 in) long and 3–8 mm (0.1–0.3 in) wide. Flowering plants have a single flower 25–30 mm (1–1 in) long and 9–11 mm (0.4–0.4 in) wide borne on a flowering stem 60–150 mm (2–6 in) high. The flowers are translucent white with reddish-brown stripes and markings. 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 (0.04–0.08 in) long. The lateral sepals are held closely against the galea, have an erect, thread-like tip 25–30 mm (0.98–1.2 in) long and a broad, flat sinus with a small notch between their bases. The labellum is 16–20 mm (0.6–0.8 in) long, about 4 mm (0.2 in) wide, thick, fleshy and reddish-brown protruding prominently above the sinus. Flowering occurs from April to August.[2][3]
Taxonomy and naming
editPterostylis erythroconcha was first formally described in 1985 by Mark Clements and David Jones from a specimen collected near Corny Point. The description was published in the fourth edition of Flora of South Australia.[1] The specific epithet (erythroconcha) is derived from the Ancient Greek words erythros meaning "red"[4]: 308 and konche meaning "snail".[4]: 530
Distribution and habitat
editThe red shell orchid grows on calcareous sand and limestone, sometimes forming large colonies, usually near the coast, in mallee. It is found in the south-east of South Australia.[2][3]
References
edit- ^ a b c "Pterostylis erythroconcha". APNI. Retrieved 27 June 2017.
- ^ a b Jones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. p. 291. ISBN 978-1877069123.
- ^ a b "Pterostylis erythroconcha". State Herbarium of South Australia: eflora SA. Retrieved 27 June 2017.
- ^ a b Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press.