Silparaja at 13:52, 13 September 2009

2009-09-13T13:52:24Z

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			{{Inc\|
			Diuris (Greek, double-tailed, alluding to the sepals). Orchidaceae. Twenty or more glabrous terrestrial orchids of Austral., rarely seen in collections in cool or warm glasshouses. The lvs. are at or near the base of the bracted st. (which is usually 1-2 ft. high), few, narrow: fls. 1 to several in a terminal raceme, conspicuous from the elongated tail-like lateral green sepals; remainder of perianth yellow, purple or white, sometimes purple-blotched or -spotted; dorsal sepal remaining close to and over the column; lip 3-parted. The species are attractive or even handsome. D. longifolia, R. Br., has fls. several, yellow and purple, moderately large; dorsal sepal broadly ovate, the lateral long and narrow; lip as long as dorsal sepal, lobed from the base: lvs. linear, one of them often very long. D. maculata, Smith, is rather slender, usually under 1 ft. tall, with long-pedicelled yellow much-spotted fls.; dorsal sepal erect and rigid, embracing the column at the base but open at the top; lip shorter than dorsal sepal, lobed from base: Ivs. narrow. B.M. 3156. D. punctata, Smith. St. 1-2 ft. or more: lvs. usually 2, and 3-6 in. long: fls. 2 or 3, blue or purplish, often dotted but not blotched; dorsal sepal typically broadly ovate-oblong; lip about as long as dorsal sepal, divided to base. L. H. B.
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	{{Taxobox		{{Taxobox
	\| color = lightgreen		\| color = lightgreen

217.113.20.108 at 11:56, 5 July 2007

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{{Taxobox
| color = lightgreen
| name = Donkey Orchids
| image = Diuris 03 gnangarra.jpg
| image_width = 250px
| image_caption = ''Diuris carinata''
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Monocotyledon|Liliopsida]]
| ordo = [[Asparagales]]
| familia = [[Orchidaceae]]
| subfamilia = [[Orchidoideae]]
| tribus = Diurideae
| subtribus = Diuridinae
| genus = '''''Diuris'''''
| genus_authority = [[James Edward Smith|Sm.]], 1798
| subdivision_ranks = Species
| subdivision =
See text.
}}

The genus '''Diuris''' belongs to the orchid family ([[Orchidaceae]]), with more than fifty described species. The genus is presently being revised, with many newly described species.

The scientific name is derived from the Greek words ''dis'' (double) and ''oura'' (tail), referring to the two lateral drooping sepals, giving a tailed appearance. The common name '''Donkey Orchid''' is logically derived from the appearance of the two lateral petals, protruding from the top of the flower like the two ears of a donkey. These features give ''Diuris'' its easily recognizable appearance.

''Diuris'' consists of perennial species native to open [[Habitat (ecology)|habitat]]s in [[Australia]] and [[Tasmania]], with the exception of one species endemic to [[Timor]].

Many species are common in Australia. They grow in large clusters, due to the vegetative growth of their tubers. The genus is one of the best known of Australian terrestrial orchids with the purple Diuris (''D. punctata'') being always popular when exhibited.

The basal, grass-like [[Leaf|leaves]] are medium-sized to large. They grow alternately or whorled. Their margins are entire. The central [[Plant stem|stem]] can grow up to 1 m high.

During summer, these terrestrial orchids shrivel and wither above the ground. Their underground tubers then become dormant.

The [[hermaphroditic]] [[flower]]s grow solitary or in several-flowered loose racemes. They can be most diverse, from small (1 cmà to large (6 cm), fragrant or not. Their 3-merous form is usually very irregular. The flowers may be blotched or lacking spots. Their colors vary from a lemon yellow, or yellow and brown, yellow and purple, yellow and orange, to pink and white, or purple. The two lateral [[petal]]s are rounded or elongated. The dorsal petal forms a hood over the [[column (botany)|column]]. The [[labellum|lip]] is three-lobed. The two lateral lobes form wings.

The flowering period is between July and November.

Pollination is by native, small [[bee]]s, lured to flowers mimicking flowers of the pea family ([[Fabaceae]]), but syrphiid flies and beetles may pollinate as well. The [[fruit]] is a non-fleshy, dehiscent [[capsule (fruit)|capsule]], containing between 30 and 500 minute [[seed]]s. These seeds mature in a matter of weeks.

Diuris can be grown in a free draining mixture and are relatively easily grown from seed using in-vitro techniques.

The orchids of Diuris are susceptible to the [[Diuris virus Y]], a positive stranded ss[[RNA virus]] from the family [[Potyviridae]]

[[Image:Diuris.PlateI.jpg|thumb|right|250px|Several Diuris species : nrs. 4 (Diuris carinata) and 12 (Diuris longifolia)]]
== Species ==
[[Image:Diuris drummondii 280403.jpg|thumb|right|250px|''Diuris drummondii'']]
[[Image:Donkey orchid gnangarra 01.jpg|thumb|right|250px|''Diuris longifolia'']]
* ''[[Diuris abbreviata]]'' F.Muell. ex Benth 1873
* ''[[Diuris aequalis]]'' F.Muell. ex Fitzg., 1876
* ''[[Diuris alba]]'' R.Br.1810
* ''[[Diuris amplissima]]'' D.L.Jones 1991
* ''[[Diuris arenaria]]'' D.L.Jones, 1999
* ''[[Diuris aurea]]'' Sm. 1804
* ''[[Diuris behrii]]'' Schltdl. 1847
* ''[[Diuris bracteata]]'' Fitzg. 1891
* ''[[Diuris brevifolia]]'' R.S.Rogers 1922
* ''[[Diuris brevissima]]'' Fitzg. ex Nicholls 1942
* ''[[Diuris brumalis]]'' D.L.Jones 1991
* ''[[Diuris byronensis]]'' D.L.Jones 2003
* ''[[Diuris callitrophila]]'' D.L.Jones 2003
* ''[[Diuris carinata]]'' Lindl. 1840 : Bee Orchid
* ''[[Diuris chrysantha]]'' D.L.Jones & M.A.Clem. 1987
* ''[[Diuris chryseopsis]]'' D.L.Jones 1998 : Snake Orchid
* ''[[Diuris concinna]]'' D.L.Jones 1991
* ''[[Diuris conspicillata]]'' D.L.Jones 1991
* ''[[Diuris corymbosa]]'' Lindl. 1840
* ''[[Diuris cuneata]]'' Fitzg. 1891
* ''[[Diuris curvifolia]]'' Lindl. 1840
* ''[[Diuris disposita]]'' D.L.Jones 1991
* ''[[Diuris drummondii]]'' Lindl. 1840 : Tall Donkey Orchid
* ''[[Diuris emarginata]]'' R.Br. 1810 : Tall Donkey Orchid
** ''Diuris emarginata'' var. ''emarginata''
** ''Diuris emarginata'' var. ''pauciflora'' (R.Br.) [[Alex George|A.S.George]] 1971
* ''[[Diuris exitela]]'' D.L.Jones 1991
* ''[[Diuris filifolia]]'' Lindl. 1840 : Cat's Face Orchid
* ''[[Diuris flavescens]]'' D.L.Jones 1991
* ''[[Diuris fragrantissima]]'' D.L.Jones & M.A.Clem. 1989
* ''[[Diuris fryana]]'' Ridl. in H.O.Forbes 1885
* ''[[Diuris heberlei]]'' D.L.Jones 1991
* ''[[Diuris laevis]]'' Fitzg. 1882 : Nannygoat Orchid
* ''[[Diuris lanceolata]]'' Lindl. 1840
* ''[[Diuris laxiflora]]'' Lindl. 1840 : Bee Orchid
* ''[[Diuris longifolia]]'' R.Br. 1810 : Common Donkey Orchid
* ''[[Diuris luteola]]'' D.L.Jones & B.Gray 1991
* ''[[Diuris maculata]]'' Sm. 1805
* ''[[Diuris magnifica]]'' D.L.Jones 1991
* ''[[Diuris micrantha]]'' D.L.Jones 1991
* ''[[Diuris ochroma]]'' D.L.Jones 1994
* ''[[Diuris oporina]]'' D.L.Jones 1991
* ''[[Diuris orientis]]'' D.L.Jones 1998
* ''[[Diuris palustris]]'' Lindl. 1840
* ''[[Diuris pardina]]'' Lindl. 1840
* ''[[Diuris parvipetala]]'' (Dockrill) D.L.Jones & M.A.Clem. 1987
* ''[[Diuris pauciflora]]'' R.Br. 1810 synonym of ''Diuris emarginata'' var. ''pauciflora'' (R.Br.) [[Alex George|A.S.George]] 1971
* ''[[Diuris pedunculata]]'' R.Br., 1810
* ''[[Diuris picta]]'' [[James Drummond|J.Drumm.]] 1853
* ''[[Diuris platichila]]'' Fitzg. 1891
* ''[[Diuris porrifolia]]'' Lindl. 1840 synonym of ''Diuris corymbosa]]'' Lindl. 1840
* ''[[Diuris praecox]]'' D.L.Jones 1991
* ''[[Diuris pulchella]]'' D.L.Jones 1991
* ''[[Diuris punctata]]'' Sm. 1804 : Purple Diuris
** ''Diuris punctata'' var. ''punctata''
** ''Diuris punctata'' var. ''sulphurea'' Rupp 1944
* ''[[Diuris purdiei]]'' Diels 1903 : Purdie's Donkey Orchid
* ''[[Diuris recurva]]'' D.L.Jones 1991
* ''[[Diuris secundiflora]]'' Fitzg. 1877
* ''[[Diuris semilunulata]]'' Messmer in H.M.R.Rupp 1944
* ''[[Diuris setacea]]'' R.Br. 1910 : Bristly Donkey Orchid
* ''[[Diuris striata]]'' Rupp 1944
* ''[[Diuris sulphurea]]'' R.Br. 1810
* ''[[Diuris tricolor]]'' Fitzg. 1885
* ''[[Diuris venosa]]'' Rupp 1926

Furthermore there are several species discovered but not named yet.

== Natural hybrids ==

* ''Diuris × fastidiosa'' R.S.Rogers 1927 (''D. lanceolata'' × ''D. palustris'')
* ''Diuris × nebulosa'' D.L.Jones 1991 (''D. aurea'' × ''D. punctata'')
* ''Diuris × palachila'' R.S.Rogers 1907 (''D. behrii'' × ''D. pardina'')
* ''Diuris × polymorpha'' Messmer in H.M.R.Rupp, 1944 (''D. lanceolata'' × ''D. platichila'')

== Reference ==
*{{cite journal | author = Jones, David L. | title = Some thoughts on the taxonomy of the genus Diuris | journal = Australasian Native Orchid Society | year = 1970}}

== External links ==
* [http://members.iinet.net.au/%7Eemntee/Diuris61.htm Description]
* [http://members.iinet.net.au/%7Eemntee/D%20magnifica%20Yel%20(TW).jpg Image]

[[Category:Orchids of Australia]]
[[Category:Orchid genera]]

Diuris - Revision history

Silparaja at 13:52, 13 September 2009

217.113.20.108 at 11:56, 5 July 2007