Prasophyllum

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Leek Orchids
Plant Info
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Diureae
Subtribe: Prasophyllinae
Genus: Prasophyllum
R.Br., 1810

Species
See text

Prasophyllum is a genus in the orchid family (Orchidaceae). Species of this genus are commonly called "Leek Orchids.' .There is no designated type species. Prasophyllum australe R.Br. was designated as lectotype (Clements, M.A. (1989). "Catalogue of Australian Orchidaceae". Australian Orchid Research 1 (109). )

The botanical name is derived from the Greek words prason (leek) and phyllon (leaf), referring the leek-like leaf.

These deciduous terrestrial orchids occur in Australia, Tasmania and a few species in New Zealand, growing on poor, sandy soils in temperate heaths and grasslands.

All species have prominent subterranean, tuberous, storage organs. They are sometimes called root-stem tuberoids, because their pole incorporates stem tissues.

Prasophyllum species grow in mycorrhizal associations with the fungus Ceratobasidium.

One can recognize the genus easily by the hollow, sheathing leaf through which the inflorescence, a spike of small inverted flowers, emerges. But many of the species are not easy to determine. Many species only flower following summer fires.

The whitish flowers are tinged or streaked with pink or green. Most of these species are fragrant. They are pollinated by insects. Interspecific hybridization is very common. Flowers from the spike can characteristics of different species.

The sepals and petals are narrow and inconspicuous. This makes them not very popular amongst orchid hunters.

The lip on the upper side of the flower is broad and slightly waved at the edge, often bearing an inner plate. This lip can be rigid and sessile or on a short claw. Some species have secretory tissue associated with the base of the labellum. The column is very short.


Species

About 110 species.

The genus is divided in several sections : Bifida, Genoplesium, Integra, Podochilus, Prasophyllum.

Genoplesium and Prasophyllum belong to the same lineage in the cladistic tree. Genoplesium is cladistically close to Prasophyllum, which brings into doubt its status as a segregate genus

References

  • Jones, D.L. (1998). "A taxonomic review of Prasophyllum in Tasmania". Australian Orchid Research 3 (95). 
  • Jones, D.L. & Clements, M.A. (2005). "Miscellaneous nomenclature notes and changes in Australian, New Guinea and New Zealand Orchidaceae". The Orchadian 15 (1): 41. 

External links