''Genoplesium insigne'', commonly known as the dark midge orchid or Wyong 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 twelve dark purple to dark reddish purple flowers. It is mostly found in heath on the Central Coast and only around fifty plants survive.

Description

''Genoplesium insigne'' is a terrestrial, perennial, deciduous,

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

with an underground tuber and a single thin, dark green leaf with a reddish base. The leaf is long, about wide with the free part long. Between five and twelve dark purple to dark reddish purple flowers are arranged along a flowering stem tall and taller than the leaf. The flowers are about wide and as with others in the genus, are inverted so that the labellum is above the

column A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...

rather than below it. The dorsal sepal is lance-shaped to egg-shaped, long, wide and concave. The lateral sepals are linear to lance-shaped, long, about wide and more or less parallel to each other. The

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s are lance-shaped to narrow egg-shaped, long and wide. The labellum is egg-shaped to elliptic, about long, wide with purple hairs up to long on the sides. There is a fleshy, dark purplish black callus in the centre of the labellum and covering less than half of it. Flowering occurs between August and November.

Taxonomy and naming

''Genoplesium insigne'' was first formally described in 2001 by David Jones who published the description in ''The Orchadian'' from a specimen collected in the Lake Macquarie State Recreation Area. In 2002, Jones and Mark Clements changed the name to ''Corunastylis insignis'' but the change is not accepted by the Australian Plant Census. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

(''insigne'') is a Latin word meaning "remarkable", "eminent" or "distinguished".

Distribution and habitat

The dark midge orchid grows in heath and heathy forest, in four small areas between Chain Valley Bay and Wyong with a further small population near Lake Macquarie.

Conservation

It is difficult to determine the precise number of plants of the ''G. insigne'' because they are difficult to locate and weather conditions affect whether or not the plants flower. There are estimated to be around fifty plants surviving. The species is classed as "Critically Endangered" under the New South Wales ''Threatened Species Conservation Act'' and the Commonwealth Government '' Environment Protection and Biodiversity Conservation Act 1999'' (EPBC) Act. The main threats to the species are weed invasion, habitat disturbance, grazing by rabbits and illegal collecting.

References

{{Taxonbar, from=Q15462738

insigne An insignia () is a sign or mark distinguishing a group, grade, rank, or function. It can be a symbol of personal power or that of an official group or governing body. On its own, an insignia is a sign of a specific or general authority and is ...

Endemic orchids of Australia Orchids of New South Wales Plants described in 2001