Genoplesium validum explained

Genoplesium validum, commonly known as the Blackdown midge orchid, is a species of small terrestrial orchid that is endemic to the Blackdown Tableland National Park in Queensland. It has a single thin leaf fused to the flowering stem and up to thirty five greenish-brown flowers with reddish stripes and a hairy labellum. This species is treated as Corunastylis valida in Queensland.

Description

Genoplesium validum is a terrestrial, perennial, deciduous, herb with an underground tuber and a single thin leaf with a reddish base and NaNsigfig=1NaNsigfig=1 long, fused to the flowering stem with the free part NaNsigfig=2NaNsigfig=2 long. Between fifteen and thirty five flowers are arranged along a flowering stem NaNsigfig=2NaNsigfig=2 long, reaching to a height NaNsigfig=1NaNsigfig=1. The flowers lean downwards, are greenish-brown, about 6sigfig=1NaNsigfig=1 long and 4sigfig=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 elliptic to narrow egg-shaped, about 4.5sigfig=1NaNsigfig=1 long, 2sigfig=1NaNsigfig=1 wide and greenish with narrow, dark purplish bands. The lateral sepals are linear to lance-shaped, about 5sigfig=1NaNsigfig=1 long, 1sigfig=1NaNsigfig=1 wide and spread widely apart from each other. The petals are linear to egg-shaped, about 3.5sigfig=1NaNsigfig=1 long and 1sigfig=1NaNsigfig=1 wide with dark purplish bands. The labellum is elliptic to broadly oblong, about 3sigfig=1NaNsigfig=1 long, 1.5sigfig=1NaNsigfig=1 wide and dark purplish-black with its edges densely covered with short, coarse purplish hairs. There is a dark purplish-black callus in the centre of the labellum and extending almost to its tip. Flowering occurs from December to April.[1] [2]

Taxonomy and naming

Genoplesium validum was first formally described in 1991 by David Jones and the description was published in Australian Orchid Research.[3] In 2002, David Jones and Mark Clements changed the name to Corunastylis valida, a name that is accepted in Queensland but not by the Australian Plant Census.[4] The specific epithet (validum) is a Latin word meaning "strong" or "powerful",[5] referring to the robust habit of this orchid.

Distribution and habitat

The Blackdown midge orchid grows in sandy soil in rocky places on the Blackdown Tableland.

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. 182.
  2. Jones. David L.. New taxa of Australian Orchidaceae. Australian Orchid Research. 1991. 2. 74–75.
  3. Web site: Genoplesium validum. APNI. 13 February 2018.
  4. Web site: Corunastylis valida. APNI. 13 February 2018.
  5. Book: Brown. Roland Wilbur. The Composition of Scientific Words. 1956. Smithsonian Institution Press. Washington, D.C.. 767.