Diuris oporina explained

Diuris oporina, commonly called the autumn donkey orchid or northern white donkeys tails^[1] 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.

Description

Diuris oporina is a tuberous, perennial herb with a single tapering, linear leaf NaNsigfig=1NaNsigfig=1 long, NaNsigfig=1NaNsigfig=1 wide with a purplish red base. Up to ten white flowers with mauve, lilac or purplish markings, NaNsigfig=1NaNsigfig=1 wide are borne on a flowering stem NaNsigfig=1NaNsigfig=1 tall. The dorsal sepal projects forward and is oblong to egg-shaped with the narrower end towards the base, NaNsigfig=2NaNsigfig=2 long and about 5sigfig=1NaNsigfig=1 wide. The lateral sepals are linear, green, NaNsigfig=2NaNsigfig=2 long and about 1sigfig=1NaNsigfig=1 wide. The petals are more or less erect, egg-shaped, NaNsigfig=2NaNsigfig=2 long and NaNsigfig=2NaNsigfig=2 wide on a purplish brown stalk NaNsigfig=2NaNsigfig=2 long. The labellum is NaNsigfig=2NaNsigfig=2 long, projects forwards below horizontal and has three lobes. The centre lobe is wedge-shaped to diamond shaped, NaNsigfig=2NaNsigfig=2 wide with mauve or purple markings. The side lobes are linear to oblong, about 2.5sigfig=1NaNsigfig=1 long and wide. There are two rounded ridge-like calli about 5sigfig=1NaNsigfig=1 long at the lower half of the mid-line of the base of the labellum. Flowering occurs mainly from March to May, sometimes later.^{[2] [3]}

Taxonomy and naming

Diuris oporina was first formally described in 1991 by David Jones from a specimen collected near Watsonville, Queensland on the Atherton Tableland and the description was published in Australian Orchid Research.^[4] The specific epithet (oporina) is derived from the Ancient Greek word oporinos meaning "autumnal",^[5] referring to the flowering period of this species.

Distribution and habitat

The autumn donkey orchid grows on ridges and sloped in forest and woodland on the drier parts of the Atherton and Evelyn tablelands.

Notes and References

1. Web site: Northern white donkeys tails – Diuris oporina. Queensland Government Department of Environment and Science. 27 March 2018.
2. Book: Jones. David L.. A complete guide to native orchids of Australia including the island territories. 2006. New Holland. Frenchs Forest, N.S.W.. 1877069124. 132.
3. Jones. David L.. New taxa of Australian Orchidaceae. Australian Orchid Research. 1991. 2. 59–60.
4. Web site: Duiris oporina. APNI. 27 March 2018.
5. Book: Brown. Roland Wilbur. The Composition of Scientific Words. 1956. Smithsonian Institution Press. Washington, D.C.. 575.