Prasophyllum alpinum

Prasophyllum alpinum, commonly known as the alpine leek orchid, is a species of orchid endemic to Tasmania. It was formerly described as occurring in mainland Australia but has smaller flowers than the species occurring there. It has a single, tube-shaped leaf and up to fourteen green to greenish-brown flowers and grows in subalpine areas.

Alpine leek orchid
Scientific classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Diurideae
Subtribe: Prasophyllinae
Genus: Prasophyllum
Species:
P. alpinum
Binomial name
Prasophyllum alpinum

Description

Prasophyllum alpinum is a terrestrial, perennial, deciduous, herb with an underground tuber and a single tube-shaped leaf, 80–200 mm (3–8 in) long and 2–5 mm (0.08–0.2 in) wide. The leaf has a white base and its free part is 80–120 mm (3–5 in) long. Between five and fourteen flowers are arranged along a flowering spike 30–100 mm (1–4 in) long. The flowers are green to greenish-brown, 5–8 mm (0.2–0.3 in) long and sometimes some of them do not open. As with others in the genus, the flowers are inverted so that the labellum is above the column rather than below it. The dorsal sepal is egg-shaped, 4–5 mm (0.16–0.20 in) long and about 2 mm (0.08 in) wide. The lateral sepals are joined along their sides and the petals are linear to egg-shaped, about 4 mm (0.2 in) long and 1 mm (0.04 in) wide. The labellum is egg-shaped to broad lance-shaped, 3–4 mm (0.1–0.2 in) long, about 2 mm (0.08 in) long and white or greenish. Flowering occurs from December to January.[2]

Taxonomy and naming

Prasophyllum alpinum was first formally described in 1810 by Robert Brown and the description was published in Prodromus Florae Novae Hollandiae et Insulae Van Diemen.[1][3] The specific epithet (alpinum) is a Latin word meaning "of high mountains".[4]

Prasophyllum colensoi from New Zealand and P. tadgellianum and P. sphacelatum from mainland Australia were formerly included with P. alpinum.[2]

Distribution and habitat

The alpine leek orchid is common in grassland and herbfields in moist areas above 650 m (2,000 ft) south of Cradle Mountain.[2]

References
  1. "Prasophyllum alpinum". APNI. Retrieved 25 October 2017.
  2. Jones, David L. (1996). "Resolution of the Prasophyllum alpinum R.Br. (Orchidaceae) complex in mainland south-eastern Australia, Tasmania and New Zealand" (PDF). Muelleria. 9: 51–62. Retrieved 25 October 2017.
  3. Brown, Robert (1810). Prodromus Florae Novae Hollandiae et Insulae Van Diemen. London. p. 318. Retrieved 25 October 2017.
  4. Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 536.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.