Pterostylis furcata

From Wikipedia, the free encyclopedia

Forked greenhood
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Cranichideae
Genus: Pterostylis
Species:
P. furcata
Binomial name
Pterostylis furcata

Pterostylis furcata, commonly known as the forked greenhood, is a species of orchid endemic to Tasmania. Flowering plants have a rosette of bright green leaves at the base of the flowering stem and a single green and white flower with the tip of the dorsal sepal pointing above the horizontal.

Description[edit]

Pterostylis furcata is a terrestrial, perennial, deciduous, herb with an underground tuber. Flowering plants have a rosette of bright green leaves loosely arranged around the base of the flowering stem, each leaf 30–80 mm (1–3 in) long and 10–20 mm (0.4–0.8 in) wide. A single green and white flower 35–40 mm (1–2 in) long and 16–20 mm (0.6–0.8 in) wide is borne on a spike 120–200 mm (5–8 in) high. The dorsal sepal and petals are fused, forming a hood or "galea" over the column but the dorsal sepal is longer than the petals, has a sharp point on its end and points slightly upwards. There is a wide gap between the lateral sepals and the galea, and there is a curved, deeply notched sinus between them. The labellum is 18–22 mm (0.7–0.9 in) long, about 3 mm (0.1 in) wide, dark-coloured, curved and protrudes above the sinus. Flowering occurs from November to February.[2]

Taxonomy and naming[edit]

Pterostylis furcata was first formally described in 1840 by John Lindley from a specimen collected in Tasmania and the description was published in The Genera and Species of Orchidaceous Plants.[1][3] The specific epithet (furcata) is a Latin word meaning "forked".[4]

Distribution and habitat[edit]

The forked greenhood grows in wet forest and in montane grassland in Tasmania.[2][5]

References[edit]

  1. ^ a b "Pterostylis furcata". APNI. Retrieved 16 May 2017.
  2. ^ 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. 307. ISBN 978-1877069123.
  3. ^ Lindley, John (1840). The Genera and Species of Orchidaceous Plants. London: Ridgways. p. 390. Retrieved 16 May 2017.
  4. ^ Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 345.
  5. ^ Jones, David L. (1998). "Contributions to the Orchidology of Tasmania". Australian Orchid Research. 3: 144–145.