Pterostylis russellii, commonly known as Russell's greenhood, is a species of orchid endemic to eastern Australia. Non-flowering plants have a rosette of leaves flat on the ground but flowering plants have a single shiny white and dark green flower on a flowering stem lacking a rosette but with a few spreading stem leaves.
| Russell's greenhood | |
|---|---|
| |
| Pterostylis russellii near Nowendoc | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Monocots |
| Order: | Asparagales |
| Family: | Orchidaceae |
| Subfamily: | Orchidoideae |
| Tribe: | Cranichideae |
| Genus: | Pterostylis |
| Species: | P. russellii
|
| Binomial name | |
| Pterostylis russellii | |
| Synonyms[2] | |
Description
editPterostylis russellii is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of between three and six dark green, oblong to heart-shaped leaves, each leaf 15–40 mm (0.6–2 in) long and 10–18 mm (0.4–0.7 in) wide. Flowering plants have a single shiny dark green and white flower 15–20 mm (0.6–0.8 in) long and 7–9 mm (0.3–0.4 in) wide on a stem 200–350 mm (8–10 in) tall with three to five stem leaves. The dorsal sepal and petals are fused, forming a hood or "galea" over the column curving forward in a semi-circle. The dorsal sepal ends with a thread-like tip 3–7 mm (0.1–0.3 in) long. The lateral sepals are held closely against the galea, have erect thread-like tips 20–30 mm (0.8–1 in) long and a protruding, V-shaped sinus between their bases. The labellum is about 11–14 mm (0.4–0.6 in) long and about 3 mm (0.1 in) wide, blackish, blunt and protruding above the sinus. Flowering occurs from April to August.[3][4]
Taxonomy and naming
editPterostylis russellii was first formally described in 1952 by Trevor Hunt from a specimen collected near Brisbane and the description was published in The Orchid Journal (California).[1] The specific epithet (russellii) honours "Mr. A.J. Russell, then Captain Russell, a keen and competent student of Australian orchids" who first collected this species.[5]
Distribution and habitat
editRussell's greenhood grows in moist, shady places in forest between Grafton in New South Wales and Gympie in Queensland.[3][4]
References
edit- ^ a b "Pterostylis russellii". APNI. Retrieved 16 July 2017.
- ^ "Pterostylis russellii". World Checklist of Selected Plant Families (WCSP). Royal Botanic Gardens, Kew.
- ^ 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. pp. 289–290. ISBN 978-1877069123.
- ^ a b "Pterostylis russellii". Royal Botanic Garden Sydney. Retrieved 16 July 2017.
- ^ Hunt, Trevor E. (1952). "A new species of Pterostylis from south Queensland". The Orchid Journal: An International Review of Orchidology. 1: 42.
External links
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Media related to Pterostylis russellii at Wikimedia Commons
