Pterostylis scabrida

Pterostylis scabrida, commonly known as the rough greenhood, is a species of orchid endemic to Tasmania. It has a rosette of leaves at the base of the plant and a single green and white flower on a rough stem. It is widespread and common in wet forests and is one of the few species of Pterostylis to grow in rainforest.

Rough greenhood
Pterostylis scabrida growing near the Rapid River in Tasmania
Scientific classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Cranichideae
Genus: Pterostylis
Species:
P. scabrida
Binomial name
Pterostylis scabrida

Description

Pterostylis scabrida is a terrestrial, perennial, deciduous, herb with an underground tuber and a rosette of dark green leaves loosely surrounding the base of the flowering stem. Each leaf is 30–60 mm long and 8–10 mm wide. A single green and white flower 20–25 mm long and 14–16 mm wide is borne on a rough flowering stem 80–250 mm high. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal is the same length as the petals and curves forward with a pointed tip. There is a wide gap between the galea and the lateral sepals. The lateral sepals are erect and have thread-like tips 14–16 mm long and a slightly bulging, V-shaped notch sinus between them. The labellum is 12–15 mm long, about 3 mm wide, brown and curved and protrudes above the sinus. Flowering occurs from October to February.[2][3]

Taxonomy and naming

Pterostylis scabrida was first formally described in 1840 by John Lindley and the description was published in his book, The Genera and Species of Orchidaceous Plants.[1][4] The specific epithet (scabrida) is a Latin word meaning "rough" or "rugged".[5]

Distribution and habitat

The rough greenhood is widespread and common in wet forests, including rainforest, throughout Tasmania.[2][3][6]

References
  1. "Pterostylis scabrida". APNI. Retrieved 27 May 2017.
  2. Jones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. p. 306. ISBN 978-1877069123.
  3. Jones, David L. (1998). "Contributions to the Orchidology of Tasmania". Australian Orchid Research. 3: 151–152.
  4. Lindley, John (1840). The Genera and Species of Orchidaceous Plants. London: Ridgways. p. 389. Retrieved 27 May 2017.
  5. Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 670.
  6. "Pterostylis". Trin Keys. Retrieved 27 May 2017.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.