Rhizanthella slateri

Rhizanthella slateri

Rhizanthella slateri is a plant belonging to the orchid family ( Orchidaceae). The species is native to eastern Australia and lives entirely underground.

Features

Vegetative habit

Rhizanthella slateri is a leaf and rootless, which grow underground plant. She has photosynthesis completely abandoned and accordingly forms no more chlorophyll; Instead, she lives myco -heterotrophic.

The 5 to 10 mm thick and 100 to 150 mm long, branched rhizome of the plant is white, fleshy and covered with overlapping stipules.

Flower

The plant flowers in October / November. Then grows from the rhizome to just below the earth's surface (in some cases even up to 2 inches protruding ) is dealt with through numerous, overlapping stipules flower stems, terminal a single so-called capitulum is on the, an upright, conical flower head with a diameter of 15-20 millimeters. The capitulum is surrounded by approximately 18 white, fleshy, 6-8 mm long and 2-3 mm wide, overlapping bracts; these are triangular and einnervig.

The tubular 15-36 individual flowers are 6-8 mm long and 3 mm wide, purple in color and are arranged in flat-topped capitulum. The densely papillose sepals and petals are non- grow, but are close to each other. The sepals are 3-4 mm long and 1.8 to 2.2 mm wide, the petals 2 to 2.3 mm long and 1.5 mm wide.

The posterior sepal is linear to filiform and the Columna bent at the tip, the lateral sepals are running at their peak also thready. The seated on a 1 millimeter long stem labellum is broad heart-shaped, 2 mm long and 2 mm wide, inflected, fleshy, densely papillose at the top and deep red.

The Columna is short and broad, their wings are too narrow, papillose, reduced ear-like appendages. The anthers are broad and curved, the scar is thickened like cushions.

Distribution, habitat, botanical history, status

The species is native to the border region of New South Wales to Queensland. Less than ten locations are known; the largest site on the slopes of Alum Mountains comprises only eight individuals. The plants grow in wooded, well-drained sites at altitudes between 10 and 1000 m. Unlike Rhizanthella gardneri the species does not seem to be dependent on a specific host plant, but is found in the company of a wide variety of plants, often with Eucalyptus species.

The first specimens of the species were discovered in 1931 by Ernest Slater on the Alum Mountain at Buladelah in New South Wales and in 1932 first described by Herman Montague Rucker Rupp slateri as Crypthanthemis. In 1984 she was assigned to the genus Rhizanthella.

Made at another site near Buladelah plans to build roads that threaten the site. As the full extent of the stocks, however, is difficult to quantify because of the underground life style, an estimate of the resulting threat to the survival of the species is not currently possible.

Rhizanthella slateri is currently out on Appendix 2 of CITES.

Swell

• David L. Jones: A complete guide to native orchids of Australia: including the Iceland territories, p.373, Frenchs Forest, 2006, ISBN 1-8770-6912-4.
• Gwen Harden: Flora of New South Wales, Vol 4, 1993, p. 219, UNSW Press, Kensington, ISBN 0-8684-0188-9