Diuris disposita

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Macleay River doubletail
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Diurideae
Genus: Diuris
Species:
D. disposita
Binomial name
Diuris disposita

Diuris disposita, commonly called the Macleay River doubletail [2] or Willawarrin doubletail, [3] is a species of orchid which is endemic to a small area in New South Wales. It has one or two linear leaves at its base and up to seven yellow flowers with brown markings. Only about fifty plants survive in grassy forest near Kempsey.

Contents

Description

Diuris disposita is a tuberous, perennial herb with usually only one linear leaf 150–300 mm (6–10 in) long and 4–5 mm (0.2–0.2 in) wide. Between two and seven yellow flowers with brown markings, 20 mm (0.8 in) wide are borne on a flowering stem 200–350 mm (8–10 in) tall. The dorsal sepal projects forward and is egg-shaped, 7–11 mm (0.3–0.4 in) long and 4–7 mm (0.2–0.3 in) wide. The lateral sepals are linear to sword-shaped, green and brownish, 10–24 mm (0.4–0.9 in) long, about 2 mm (0.08 in) wide, turned downwards and parallel to, or crossed over each other. The petals are more or less erect, spread apart from each other with an elliptic to egg-shaped blade 6–9 mm (0.2–0.4 in) long and 4.5–6.5 mm (0.2–0.3 in) wide on a green stalk 4–7 mm (0.2–0.3 in) long. The labellum is 7–9 mm (0.3–0.4 in) long and has three lobes. The centre lobe is egg-shaped, 4–7 mm (0.2–0.3 in) wide and the side lobes are linear to oblong, 2–3 mm (0.08–0.1 in) long and about 1 mm (0.04 in) wide. There are two ridge-like calli about 4.5 mm (0.18 in) long near the base of the mid-line of the base of the labellum. Flowering occurs in September and October. [2] [3] [4] [5]

Taxonomy and naming

Diuris disposita was first formally described in 1991 by David Jones from a specimen collected near north-west of Kempsey and the description was published in Australian Orchid Research. [6] The specific epithet (disposita) is a Latin word meaning "distributed" or "arranged", [7] referring to the widely spaced flowers on the flowering stem. [4]

Distribution and habitat

The Macleay River doubletail grows in grassy open forest near the Macleay River north-west of Kempsey. [2] [4]

Conservation

Diuris disposita is classified as "endangered" under the New South Wales Biodiversity Conservation Act 2016 . The main threats to the species are illegal collecting, habitat destruction and inappropriate fire regimes. [3] Fewer than fifty plants are known, none in a conservation reserve. [8]

Related Research Articles

<i>Diuris pardina</i> Species of orchid

Diuris pardina, commonly known as the leopard orchid or leopard doubletail is a species of orchid which is endemic to south-eastern Australia. It has two or three grass-like leaves and up to ten yellow flowers with reddish-brown marks and blotches.

Diuris maculata, commonly known as the spotted doubletail is a species of orchid which is endemic to New South Wales. It has up to two or three folded leaves and a flowering stem with up to eight yellow flowers with brown to blackish markings. It is similar to D. pardina which has darker flowers with larger brown markings.

<i>Diuris aequalis</i> Species of orchid

Diuris aequalis, commonly called the buttercup doubletail, is a species of orchid which is endemic to New South Wales. It has two rolled leaves and spikes of two to five golden-yellow to orange flowers and is classified as "vulnerable".

<i>Diuris venosa</i> Species of orchid

Diuris venosa, commonly known as the veined doubletail is a species of orchid which is endemic to New South Wales. It has a few thin, erect leaves and up to four white to lilac-coloured flowers with deep red to purple blotches and lines.

<i>Diuris abbreviata</i> Species of orchid

Diuris abbreviata, commonly known as the lemon doubletail, is a species of orchid that is endemic to eastern Australia. It has two or three leaves and a flowering stem with up to nine yellow flowers with darker markings.

<i>Diuris eborensis</i> Species of orchid

Diuris eborensis is a species of orchid which is endemic to eastern Australia. It has up to six grass-like leaves and a flowering stem with up to four pale yellowish flowers with dark reddish purple streaks.

<i>Diuris praecox</i> Species of orchid

Diuris praecox, commonly known as the early doubletail, Newcastle doubletail or rough doubletail is a species of orchid which is endemic to New South Wales. It has two or three grass-like leaves and up to ten light yellow flowers with a few dark brown marks. It is threatened by urbanisation.

<i>Diuris arenaria</i> Species of orchid

Diuris arenaria, commonly known as the Tomaree donkey orchid or sand doubletail is a species of orchid which is endemic to a very small area of New South Wales. It has two grass-like leaves and up to nine mauve or light purple and white flowers. It has a very limited distribution near Newcastle.

Diuris bracteata is a species of orchid which is endemic to New South Wales. It has two folded leaves and up to eight yellow flowers with blackish marks. After its collection in a Sydney suburb in 1888, no further collections were made and the species was presumed extinct until 2004 when it was rediscovered near Gosford.

Diuris callitrophila, commonly known as the Oaklands doubletail or Oaklands diuris, is a species of orchid which is endemic to a small part of southern New South Wales. It has two or three leaves and up to nine whitish and mauve flowers with darker markings and unusually long lateral sepals.

Diuris curta is a species of orchid that is endemic to eastern Australia. It has one or two leaves and up to five bright yellow flowers with two small dark spots on the dorsal sepal. It grows on coastal headlands between about Byfield in Queensland and Hat Head in New South Wales.

Diuris exitela, commonly called the Mount Moffat doubletail, is a species of orchid which is endemic to central western Queensland. It has two linear leaves at its base, up to twelve bright yellow flowers with dark brown markings and grows on sandstone cliffs and ridges.

Diuris flavescens, commonly called the pale yellow doubletail or Wingham doubletail, is a species of orchid which is endemic to a small area in New South Wales. It has two linear leaves at its base and up to five pale yellow flowers with dark brown markings. Fewer than 200 plants survive in grassy forest near Wingham.

Diuris fragrantissima, commonly called the fragrant doubletail or Sunshine diuris, is a species of orchid which is endemic to a small area to the west of Melbourne. It has two linear leaves at its base and up to twelve white flowers with mauve or pale purple markings with unusually long lateral sepals. Only about thirty plants survive in grassland near Sunshine.

Diuris luteola, commonly called the northern doubletail, is a species of orchid which is endemic to Queensland. It has a single linear leaf at its base and up to six pale yellow flowers with a few brown markings. It grows in shallow, stony soil on tablelands in eastern parts of the state.

Diuris oporina, commonly called the autumn donkey orchid or northern white donkeys tails is a species of orchid that is endemic to Queensland. It has a single tapering, linear leaf at its base and up to ten white flowers with mauve to purple markings. It grows in the drier parts of the tablelands in Far North Queensland.

<i>Diuris palustris</i> Species of orchid

Diuris palustris, commonly known as the swamp doubletail or swamp diuris is a species of orchid which is endemic to south-eastern Australia. It has a tuft of between eight and ten twisted leaves and up to four yellow flowers with brown spots and blotches marks and blotches.

Diuris platichila, commonly known as the Blue Mountains doubletail, is a species of orchid that is endemic to a few isolated places in the Blue Mountains in New South Wales. It has two leaves and up to eight yellow flowers with dark markings on the dorsal sepal and labellum. It has relatively long, thin lateral sepals and the central lobe of the labellum is wedge-shaped. It forms hybrids with other species of Diuris.

Diuris secundiflora, commonly known as the one-sided donkey orchid, is a poorly-known species of orchid that is endemic to New South Wales. It has a single grass-like leaf and up to eight yellow flowers that are sometimes spotted and are all arranged on one side of the flowering stem.

Diuris striata is a poorly-known species of orchid that is endemic to New South Wales. It has a two grass-like leaves and about four mauve flowers with dark purple streaks on the labellum.

References

  1. "Diuris disposita". World Checklist of Selected Plant Families (WCSP). Royal Botanic Gardens, Kew.
  2. 1 2 3 Jones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. p. 129. ISBN   1877069124.
  3. 1 2 3 "Willawarrin Doubletail - profile". New South Wales Government Office of Environment and Heritage. Retrieved 18 March 2018.
  4. 1 2 3 Jones, David L. (1991). "New taxa of Australian Orchidaceae". Australian Orchid Research. 2: 55.
  5. "Diuris disposita". Royal Botanic Garden Sydney. Retrieved 18 March 2018.
  6. "Duiris disposita". APNI. Retrieved 18 March 2018.
  7. Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 612.
  8. "Diuris disposita (a terrestrial orchid) - endangered species listing". New South Wales Government Office of Environment and Heritage. Retrieved 18 March 2018.