Pterostylis commutata

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Midland rustyhood
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Cranichideae
Genus: Pterostylis
Species:
P. commutata
Binomial name
Pterostylis commutata
Synonyms [1]

Oligochaetochilus commutatus(D.L.Jones & M.A.Clem.) D.L.Jones & M.A.Clem.

Contents

Pterostylis commutata, commonly known as the midland rustyhood is a plant in the orchid family Orchidaceae and is endemic to Tasmania. It has a rosette of leaves near its base and up to five translucent white and green flowers with a hairy, insect-like labellum. It is only found in a small area near Tunbridge and Ross .

Description

Pterostylis commutata is a terrestrial, perennial, deciduous, herb with an underground tuber and a rosette of between six and ten leaves. Each leaf is 15–30 mm (0.6–1 in) long and 4–8 mm (0.2–0.3 in) wide. Flowering plants have a rosette at the base of the flowering stem but these are usually withered by flowering time. Up to five translucent white flowers with green markings and 45–55 mm (1.8–2.2 in) long and 7–9 mm (0.3–0.4 in) wide are borne on a flowering spike 100–250 mm (4–10 in) tall. The flowers lean forward slightly and there are three or four stem leaves wrapped around the flowering stem. The dorsal sepal and petals form a hood called the "galea" over the column with the dorsal sepal having a thread-like tip 15–20 mm (0.6–0.8 in) long. The lateral sepals are the same width as the galea, dished and have densely hairy edges. They taper suddenly to narrow, thread-like tips 15–30 mm (0.6–1 in) long and parallel to each other. The labellum is green or brown, thin and insect-like, 6–7 mm (0.2–0.3 in) long and about 4 mm (0.2 in) wide. The edges of the labellum are wavy, with short, bristly hairs and there are two longer bristles near the "head" end. Flowering occurs from December to January. [2] [3] [4]

Taxonomy and naming

Pterostylis commutata was first formally described in 1993 by David Jones from a specimen collected near Ross and the description was published in Muelleria . [1] [2] The specific epithet (commutata) is derived from the Latin word commutatus, 'changed', referring to the divergence of this species following isolation from related species. [2]

Distribution and habitat

The midlands rustyhood grows in grassy woodland near Tunbridge and Ross. [2] [3] [4]

Conservation

Pterostylis commutata is listed as "critically endangered" under the (CR) under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and as "endangered" under the Tasmanian Government Threatened Species Protection Act 1995 . It is only known form an area of about 75 km2 (30 sq mi) and the largest of the five populations only contains seventeen plants. The main threats to the species' survival include agricultural activities, habitat alteration and weed invasion. [4] [5]

Related Research Articles

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<i>Pterostylis basaltica</i> Species of orchid

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<i>Pterostylis cheraphila</i> Species of orchid

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<i>Pterostylis despectans</i> Species of orchid

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<i>Pterostylis cobarensis</i> Species of orchid

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<i>Pterostylis lingua</i> Species of orchid

Pterostylis lingua, commonly known as the large-lipped rustyhood, is a plant in the orchid family Orchidaceae and is endemic to south-eastern Australia. It has a rosette of leaves and up to ten dark reddish-brown flowers with translucent "windows" and a blackish, insect-like labellum.

<i>Pterostylis planulata</i> Species of orchid

Pterostylis planulata, commonly known as the flat rustyhood, is a plant in the orchid family Orchidaceae and is endemic to Victoria. It has a rosette of leaves at its base and up to seven translucent flowers with green stripes. The flowers have a thin, dark green, insect-like labellum.

<i>Pterostylis smaragdyna</i> Species of orchid

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<i>Pterostylis squamata</i> Species of orchid

Pterostylis squamata, commonly known as the southern rustyhood or ruddyhood, is a plant in the orchid family Orchidaceae and is endemic to south-eastern Australia. Flowering plants have up to ten translucent green flowers with reddish-brown markings and a hairy, insect-like labellum. Non-flowering plants have a rosette of four to eight egg-shaped leaves. This species is very similar to Pterostylis rufa which has a narrower labellum and other minor differences.

Pterostylis arenicola, commonly known as the sandhill rustyhood is a plant in the orchid family Orchidaceae and is endemic to South Australia. It has a rosette of leaves near its base and up to ten reddish-brown and white flowers with a dark brown, insect-like labellum. Its distribution is now restricted to areas around Lake Alexandrina.

Pterostylis ciliata, commonly known as the hairy rufous greenhood, tall rusthood or hairy rustyhood is a plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. It has a relatively large rosette of leaves at its base and up to eight or more green and brown flowers which lean forward and have a small, fleshy, insect-like labellum covered with hairs.

<i>Pterostylis gibbosa</i> Species of orchid

Pterostylis gibbosa, commonly known as the Illawarra rustyhood, or Illawarra greenhood, is a plant in the orchid family Orchidaceae and is endemic to New South Wales. It has a rosette of leaves at its base and up to nine bright green flowers with translucent "windows", relatively wide lateral sepals with short-pointed tips and a dark, fleshy, insect-like labellum.

Pterostylis lepida, commonly known as the Halbury greenhood is a plant in the orchid family Orchidaceae and is endemic to South Australia. Both flowering and non-flowering plants have a rosette of leaves. Flowering plants have up to ten green flowers with brown and translucent striations and a small, insect-like labellum. It is only known from two small populations.

<i>Pterostylis leptochila</i> Species of orchid

Pterostylis leptochila, commonly known as the Ravensthorpe rufous greenhood or narrow-lipped rustyhood is a plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. Both flowering and non-flowering plants have a relatively large rosette of leaves. Flowering plants also have up to five large translucent white flowers with olive green and brown lines and markings and a narrow, insect-like labellum.

Pterostylis petrosa, commonly known as the Riverina rustyhood, is a plant in the orchid family Orchidaceae and is endemic to New South Wales. It has a rosette of leaves at its base and up to eight dark brown flowers with transparent "windows", long spreading tips on the lateral sepals and a thin, brown, insect-like labellum.

Pterostylis picta, commonly known as the painted rufous greenhood or painted rustyhood is a plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. Both flowering and non-flowering plants have a relatively large rosette of leaves. Flowering plants also have up to seven large translucent white flowers with green and brown stripes and markings and a fleshy, insect-like labellum.

Pterostylis saxicola, commonly known as the Sydney plains rustyhood, or Sydney plains greenhood, is a plant in the orchid family Orchidaceae and is endemic to New South Wales. It has a rosette of leaves at its base and up to ten reddish-brown flowers with translucent "windows", relatively wide lateral sepals with short-pointed tips and a dark brown, fleshy, insect-like labellum.

<i>Pterostylis tasmanica</i> Species of orchid

Pterostylis tasmanica, commonly known as the small bearded greenhood, is a species of orchid in the family Orchidaceae which is native to south-eastern Australia and New Zealand. It has a single green flower with translucent "windows" and a long, thin labellum bordered with golden hairs. It is similar to P. plumosa but is shorter, with smaller leaves and flowers but a more densely feathery labellum.

References

  1. 1 2 3 "Pterostylis commutata". APNI. Retrieved 23 June 2017.
  2. 1 2 3 4 Jones, David L. (1994). "New species of Orchidaceae from south-eastern Australia". Muelleria. 8 (2): 186–189. Retrieved 25 July 2019.
  3. 1 2 Jones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. pp. 325–326. ISBN   978-1877069123.
  4. 1 2 3 "Threatened species listing statement - Midland greenhood (Pterostylis commutata)" (PDF). Tasmanian Government Department of Primary Industries, Parks, Water and Environment. Retrieved 23 June 2017.
  5. "Midlands greenhood Pterostylis commutata". Australian Government Department of the Environment. Retrieved 23 June 2017.