Genoplesium systenum explained

Genoplesium superbum, commonly known as the Kangarooby midge orchid, is a species of small terrestrial orchid that is endemic to New South Wales. It has a single thin leaf and up to thirty two hairy, light reddish flowers which lean downwards and have a dark purple labellum.

Description

Genoplesium systenum is a terrestrial, perennial, deciduous, herb with an underground tuber and a single thin leaf NaNsigfig=1NaNsigfig=1 long with the free part NaNsigfig=1NaNsigfig=1 long. Between twelve and thirty two light reddish flowers are arranged along a flowering stem NaNsigfig=1NaNsigfig=1 long, reaching to a height of NaNsigfig=1NaNsigfig=1. The flowers lean downwards and are about 6sigfig=1NaNsigfig=1 wide. As with others in the genus, the flowers are inverted so that the labellum is above the column rather than below it. The dorsal sepal is broadly egg-shaped, about 3.5sigfig=1NaNsigfig=1 long, 2.5sigfig=1NaNsigfig=1 wide and greenish with reddish-purple bands and hairy edges. The lateral sepals are linear to lance-shaped, about 5sigfig=1NaNsigfig=1 long, 1.5sigfig=1NaNsigfig=1 wide, light reddish green and spread widely apart from each other. The petals are narrow egg-shaped, about 3sigfig=1NaNsigfig=1 long, 1sigfig=1NaNsigfig=1 wide with hairy edges and a similar colour to the dorsal sepal. The labellum is narrow egg-shaped, dark purple, about 3.5sigfig=1NaNsigfig=1 long and 1.5sigfig=1NaNsigfig=1 wide with coarse, spreading hairs up to 1sigfig=1NaNsigfig=1 long on its edges. There is a dark purple callus in the centre of the labellum and covering about three-quarters of its surface. Flowering occurs from February to April.[1] [2] [3]

Taxonomy and naming

The Kangarooby midge orchid was first formally described in 1991 by David Jones and the description was published in Australian Orchid Research.[4] In 2002, Jones and Mark Clements changed the name to Corunastylis systena but that name is not accepted by the Australian Plant Census.[5] The specific epithet (systenum) derived from the Ancient Greek word systenos meaning "tapering to a point",[6] referring to the shape of the labellum of this orchid. (Kangarooby is a locality near Forbes.)

Distribution and habitat

Genoplesium systenum grows below shrubs in forested ridges and slopes on the ranges near Cowra, including the Conimbla National Park and Weddin Mountains National Park.

Notes and References

  1. 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. 178.
  2. Jones. David L.. New taxa of Australian Orchidaceae. Australian Orchid Research. 1991. 2. 72–73.
  3. Web site: Jones. David L.. Genoplesium systenum. Royal Botanic Garden Sydney. 11 February 2018.
  4. Web site: Genoplesium systenum. APNI. 11 February 2018.
  5. Web site: Corunastylis systena. APNI. 11 February 2018.
  6. Book: Brown. Roland Wilbur. The Composition of Scientific Words. 1956. Smithsonian Institution Press. Washington, D.C.. 623.