Rhizanthella gardneri
Western Underground Orchid Rhizanthella gardneri
Conservation status
Endangered (EPBC Act)
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Monocots
Order:	Asparagales
Family:	Orchidaceae
Subfamily:	Epidendroideae
Tribe:	Diurideae
Subtribe:	Rhizanthellinae
Genus:	Rhizanthella
Species:	R. gardneri
Binomial name
Rhizanthella gardneri R. S. Rogers (1928)

Rhizanthella gardneri, also known as Western Underground Orchid, was discovered in the spring of 1928 in the wheatbelt of Western Australia.

Jack Trott had bent to investigate an odd crack that had appeared in his garden's soil, and had noticed a sweet smell that arose from the ground. Scraping away the soil, he soon uncovered a tiny white flower, about half an inch across, growing underground. What he had found was an entirely new type of orchid.

The white leafless plant is made up of a tube which produces a flowerhead. Unlike any other orchid in Australia, the Western Australian underground orchid remains completely underground for its whole life. Not being able to obtain the sun's energy, it instead feeds on the broom honey myrtle, a shrub. It is linked to it by a fungus named Thanatephorus gardneri.

This particular orchid is a myco-heterotroph as it relies completely on the Melaleuca uncinata and a mycorrhiza fungus for its nutrients and carbon dioxide. Having received this from the fungus the plant is then able to convert the water, nutrients and carbon dioxide into the energy needed for growth and maintenance.

The plant blooms in May and June and measures 2.5–3 cm. The flower head contains 8 to 90 small dark maroon flowers.

Rhizanthella gardneri reproduces vegetatively by which it can produce three daughter plants, as well as sexually. In the latter case the pollinated flower will then take six months to mature - pollination is thought to be effected by some animal species attracted by the fragrance. The seed is thought to be dispersed by Marsupialia, who eat the fruit, but substantial findings are hard to come by as only 19 mature specimens of the orchid are known to currently exist in the wild and only 300 specimens have been collected to date.

[edit] See also

• Rhizanthella slateri

[edit] References

• Reader's Digest Ltd. (1989). Facts and Fallacies - Stories of the Strange and Unusual. Reader's Digest Ltd. Page 39. ISBN 0864380879.
• Hoffman, N., Brown, A. (1998). Orchids of South-west Australia. University of Western Australia Press, Nedlands.Rev. 2nd ed. with suppl. ISBN 1876268182
• Jones, David L. (2006). A complete guide to native orchids of Australia: including the island territories. Frenchs Forest. ISBN 1-8770-6912-4.

[edit] External links

Wikimedia Commons has media related to: Rhizanthella gardneri

• Orchid Society of Western Australia