Rhizanthella omissa
| Rhizanthella omissa | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Rhizanthella omissa | ||||||||||||
| DLJones & MAClem. |
Rhizanthella omissa is a plant type from the family of orchids (Orchidaceae). It was first described in 2006 on the basis of two herbarium specimens collected in 1958. The species is native to southeast Australia and lives completely underground.
features
Vegetative habit
Rhizanthella omissa is a leafless and rootless plant that grows underground. It has completely given up photosynthesis and accordingly no longer forms chlorophyll , instead it lives myco-heterotrophic .
The 10 to 15 millimeter thick and 100 to 150 millimeter long rhizome of the plants is white and fleshy and covered with isolated stipules .
blossom
The plant blooms in October / November. Then a flower stem grows from the rhizome to just below the surface of the earth , with a single so-called capitulum at the end , an upright, conical flower head with a diameter of 20 to 25 millimeters, that of up to 25 white, fleshy, 10 to 16 millimeters long and 5 to 7 millimeters wide, overlapping bracts is bordered. The bracts are triangular and single-nerved.
The between fifteen and thirty short, tubular single flowers are 8 to 10 millimeters long and 5 millimeters wide, reddish in color and arranged in the flattened capitulum. The weakly papillary sepals and petals are not grown, but are close to each other. The sepals are 6.5 to 10 millimeters long and 2.5 to 3 millimeters wide, the petals 3.6 to 4 millimeters long and 1.5 millimeters wide. The labellum , sitting on a 1 millimeter long stalk, is narrowly elliptical, 3 millimeters long and 2 millimeters wide, inflected, fleshy, densely papillary and deep red.
Distribution, habitat, botanical history
The species has only been found once, in 1958, during construction work in Lamington National Park in Queensland . The plants grew in old, extensive Casuarinaceae forests in bushy undergrowth on basaltic clay at an altitude of 1200 m. The two specimens collected there have since been in the Queensland Herbarium and served as the basis for the first description in March 2006.
swell
- David L. Jones: A complete guide to native orchids of Australia: including the island territories. , p.373, Frenchs Forest, 2006, ISBN 1-8770-6912-4