Pterostylis divaricata

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Northern striped greenhood
Pterostylis divaricata Gara Gorge.jpg
Pterostylis divaricata at Gara Gorge
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Cranichideae
Genus: Pterostylis
Species:
P. divaricata
Binomial name
Pterostylis divaricata
(D.L.Jones & L.M.Copel.) L.M.Copel. & D.L.Jones [1]
Synonyms [2]

Diplodium divaricatum D.L.Jones & L.M.Copel.

Pterostylis divaricata, commonly known as northern striped greenhood, [3] is a species of orchid endemic to northern New South Wales. It grows in colonies of genetically identical plants. As with similar orchids, plants in flower differ from those that are not. Those not in flower have a rosette of leaves that lie flat on the ground. Plants in flower lack a rosette at the base but have up to ten translucent white flowers with green and brown stripes. This greenhood is similar to P. striata but has larger flowers and a longer tip on the dorsal sepal.

Contents

Habit Pterostylis habit (2).jpg
Habit

Description

Pterostylis divaricata is a terrestrial, perennial, deciduous, herb with an underground tuber and when not flowering, a rosette of five to nine dark green, broad egg-shaped leaves that lie flat on the ground. Each leaf is 5–14 millimetres (0.2–0.6 in) long and 4–11 millimetres (0.2–0.4 in) wide. Plants in flower usually have only one, 25–30 millimetres (0.98–1.2 in) long, borne on a thin, smooth flowering stem 80–200 millimetres (3–8 in) high. Three to five dark green stem leaves 20–30 millimetres (0.8–1 in) long and 3–5 millimetres (0.1–0.2 in) wide are arranged on the side of the flowering spike. The flowers are translucent white with green and brown stripes. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal is 35–40 millimetres (1–2 in) long, 10–12 millimetres (0.4–0.5 in) wide and gradually tapers to a thread-like tip 5–8 millimetres (0.2–0.3 in) long. The lateral sepals are erect, held closely against the galea with thread-like tips about 20–25 millimetres (0.8–1 in) long that are held high above the galea. The petals are oblong to lance-shaped, 24–28 millimetres (0.9–1 in) long, about 5 millimetres (0.2 in) wide and curved with flanges about 2 millimetres (0.08 in) wide. The sinus between the bases of the lateral sepals bulges forward with a V-shaped notch in the centre. The labellum is white with a brown tip and curves forward slightly, just visible above the sinus. Flowering occurs from March to May. [3] [4]

Taxonomy and naming

This greenhood was first formally described in 2016 by David Jones and Lachlan Copeland and given the name Diplodium divaricatum. The description was published in the Australian Orchid Review from a specimen collected on Mount Duval. [4] [5] In the same year, the same authorities changed the name to Pterostylis divaricata "to allow for the different taxonomic views held at generic level within the subtribe". [1] The specific epithet (divaricata) is a Latin word meaning "spread apart", [6] referring to the spread tips of the lateral sepals. [4]

This species has previously been known as Pterostylis sp. aff. alata. [3]

Distribution and habitat

Pterostylis divaricata grows with grasses, ferns and shrubs in woodland and forest on the higher parts between the New England Tableland and Mummel Gulf National Park. [3] [4]

Related Research Articles

<i>Pterostylis grandiflora</i>

Pterostylis grandiflora, commonly known as the cobra greenhood or superb greenhood, is a species of orchid endemic to south-eastern Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a green and white, striped flower with deep red-brown markings especially on its "galea", and a sharply pointed dorsal sepal.

<i>Pterostylis abrupta</i>

Pterostylis abrupta, commonly known as the tablelands greenhood, is a species of orchid endemic to New South Wales. It is distinguished from similar greenhood orchids by its thick, flat, platform-like sinus and blunt labellum which is only just visible above the sinus.

<i>Pterostylis aestiva</i>

Pterostylis aestiva, commonly known as the long-tongued summer greenhood, is a species of orchid endemic to south-eastern Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike.

<i>Pterostylis tenuissima</i>

Pterostylis tenuissima, commonly known as the swamp greenhood, is a species of orchid endemic to the southern mainland of Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike. This greenhood has small translucent white flowers with dark green stripes and markings and both the dorsal sepal and lateral sepals have relatively long, thread-like tips.

<i>Pterostylis laxa</i>

Pterostylis laxa, commonly known as the antelope greenhood, is a species of orchid endemic to south-eastern Australia. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike. This greenhood has green and white flowers with darker green or brown markings and a dorsal sepal with a long thread-like tip.

<i>Pterostylis rubescens</i>

Pterostylis rubescens, commonly known as the blushing tiny greenhood, is a species of orchid endemic to south-eastern Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants lack a rosette at the base and have up to eighteen tiny green, white and brownish flowers.

Pterostylis agathicola, commonly known as the kauri greenhood, is a species of orchid endemic to the North Island of New Zealand. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering spike. It grows almost exclusively in kauri forest and has a relatively large green and transparent white flower.

<i>Pterostylis amabilis</i>

Pterostylis amabilis is a species of orchid endemic to eastern Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants lack a rosette at the base but have up to ten tiny white and red to reddish-brown flowers. It is similar to P. parviflora but has larger rosette leaves and larger, more brightly coloured flowers.

Pterostylis anatona, commonly known as the Eungella greenhood, is a species of orchid endemic to Queensland. It has a rosette of wrinkled leaves at the base of the plant and a single light green and white flower, reddish towards its tip. It grows in higher areas between Eungella and the Blackdown Tableland National Park.

Pterostylis aquilonia, commonly known as the northern cobra greenhood, is a species of orchid endemic to Queensland. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves, but the flowering plants lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a relatively large green, white and reddish-brown self-pollinating flower.

Pterostylis crassichila, commonly known as the plump northern greenhood, is a species of orchid endemic to Queensland. It has a rosette of leaves at the base of the plant and a single white flower with green lines, reddish towards its tip. It grows in higher areas of north Queensland.

<i>Pterostylis daintreana</i>

Pterostylis daintreana, commonly known as Daintree's greenhood, is a species of orchid endemic to eastern Australia. The non-flowering plants have a rosette of leaves on short stalks but flowering plants have up to ten flowers with rosettes on the side of the flowering spike. The flowers are translucent white with dark green lines and long, downcurved lateral sepals.

<i>Pterostylis elegans</i>

Pterostylis elegans, commonly known as the elegant greenhood, is a species of orchid endemic to New South Wales. Non-flowering plants have a rosette of leaves flat on the ground but flowering plants have a single translucent white and dark green flower with reddish-brown markings near the tip.

Pterostylis erythroconcha, commonly known as the red shell orchid, is a species of orchid endemic to South Australia. As with similar orchids, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves but the flowering plants have a single flower with leaves on the flowering spike. This greenhood has a white and green flower with reddish brown markings and a long, fleshy, curved labellum.

Pterostylis paludosa, commonly known as swamp greenhood, is a species of greenhood orchid endemic to New Zealand. As with similar orchids, plants in flower differ from those that are not. Those not in flower have a rosette of leaves on a short stalk but plants in flower lack a rosette and have a single flower with leaves on the flowering spike. This greenhood has a translucent white flower with pale to yellowish-green stripes.

<i>Pterostylis reflexa</i>

Pterostylis reflexa, commonly known as the dainty greenhood, is a species of orchid endemic to New South Wales. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering stem. This greenhood has a relatively large white, green and light brown flower with a long, curved dorsal sepal and a protruding labellum.

Pterostylis silvicultrix, commonly known as the Chatham Island greenhood or tutukiwi, is a species of orchid which is endemic to Chatham Island and nearby islands. Non-flowering plants have a rosette of leaves but flowering plants have leaves on the flowering stem, some of which reach above the single translucent white flower with dark green stripes. It is similar to Pterostylis banksii which occurs on both of the main islands of New Zealand but that species lacks the orange or reddish-brown tips on the flowers of this species.

Pterostylis stenosepala, commonly known as the narrow-sepalled leafy greenhood, is a plant in the orchid family Orchidaceae and is endemic to New South Wales. Flowering plants have up to six shiny, translucent green flowers with darker green stripes. The flowers have an insect-like labellum which is green with a dark green mound on its upper end. Non-flowering plants have a rosette of leaves on a stalk, but flowering plants lack the rosette, instead having between four and eight stem leaves.

Pterostylis subtilis, commonly known as the thin mountain greenhood, is a species of orchid endemic to New South Wales. It has a rosette of leaves and when flowering a single translucent white flower with dark green lines, a narrow, deeply notched sinus between the lateral sepals and a curved, protruding labellum.

<i>Pterostylis torquata</i>

Pterostylis torquata, commonly known as the collared greenhood, is a species of orchid endemic to New South Wales. As with similar greenhoods, the flowering plants differ from those which are not flowering. The non-flowering plants have a rosette of leaves flat on the ground but the flowering plants have a single flower with leaves on the flowering stem. This greenhood has a white flower with dark green and dark brown markings, although in some areas, the flowers lack the brown markings. The sinus between the lateral sepals is platform-like.

References

  1. 1 2 "Pterostylis divaricata". APNI. Retrieved 6 April 2018.
  2. "Pterostylis divaricata". World Checklist of Selected Plant Families (WCSP). Royal Botanic Gardens, Kew.
  3. 1 2 3 4 Jones, David L. "Pterostylis divaricata". Royal Botanic Garden Sydney. Retrieved 31 March 2021.
  4. 1 2 3 4 Jones, David L.; Copeland, Lachlan M. (2016). "Four new species of Orchidaceae from the New England Tablelands of New South Wales". Australian Orchid Review. 81 (6): 42–44.
  5. "Diplodium divaricatum". APNI. Retrieved 16 April 2018.
  6. Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 743.