''Genoplesium nudum'', commonly known as the tiny midge orchid in

Australia Australia, officially the Commonwealth of Australia, is a sovereign ''Sovereign'' is a title which can be applied to the highest leader in various categories. The word is borrowed from Old French , which is ultimately derived from the L ...

or the red midge orchid in New Zealand, is a small terrestrial orchid native to south-eastern Australia and New Zealand. It has a single thin leaf fused to the flowering stem and up to forty small, reddish-purple or green and red flowers. Australian and New Zealand authorities use the name ''Corunastylis nuda'' but ''Genoplesium nudum'' and ''Prasophyllum transversum'' are used by the World Checklist of Selected Plant Families.

Description

''Genoplesium nudum'' is a terrestrial, perennial,

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, a ...

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 Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growin ...

and a single thin leaf long and fused to the flowering stem with the free part long. Between five and forty reddish-purple or green and red flowers are crowded along a flowering stem tall. The flowers lean forwards and are about long, wide and often do not open fully. The flowers 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 Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal co ...

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined ...

is egg-shaped, about long and about wide. The

lateral Lateral is a geometric term of location which may refer to: Healthcare *Lateral (anatomy), an anatomical direction * Lateral cricoarytenoid muscle * Lateral release (surgery), a surgical procedure on the side of a kneecap Phonetics *Lateral co ...

sepals are lance-shaped, about long, wide, fused at the base then free from each other and curved downwards. The

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

s are egg-shaped, long and wide with a pointed tip. The labellum is egg-shaped, thick and fleshy, long, wide with fine teeth along its edges. There is a channelled, egg-shaped

callus A callus is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on the feet and hands, but they may o ...

in the centre of the labellum and extending almost to its tip. Flowering occurs between December and March in Australia and until August in New Zealand.

Taxonomy and naming

The tiny midge orchid was first formally described in 1853 by

Joseph Dalton Hooker Sir Joseph Dalton Hooker (30 June 1817 – 10 December 1911) was a British botanist and explorer in the 19th century. He was a founder of geographical botany and Charles Darwin's closest friend. For twenty years he served as director of ...

who gave it the name ''Prasophyllum nudum'' and published the description in '' Flora Novae-Zelandiae''. In 1989, David Jones and Mark Clements changed the name to ''Genoplesium nudum'' and in 2002 changed the name again to ''Corunastylis nuda''. 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 ...

(''nuda'') is a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

word meaning "bare" or "naked". ''Prasophyllum transversum'' was formally described by Robert D. FitzGerald in 1888 but Jones and Clements regarded this as a

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are al ...

of ''Genoplesium nudum'', now known as ''C. nuda'' in the countries where it occurs.

Distribution and habitat

''Genoplesium nudum'' usually grows in moist, grassy forest. It is found

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

south from the

New England New England is a region comprising six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and by the Canadian province ...

region, in eastern Victoria, in

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

and in the

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''no ...

South South is one of the cardinal directions or compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Proto-Germanic ''*sunþa ...

and

Chatham Islands The Chatham Islands ( ) ( Moriori: ''Rēkohu'', 'Misty Sun'; mi, Wharekauri) are an archipelago in the Pacific Ocean about east of New Zealand's South Island. They are administered as part of New Zealand. The archipelago consists of about t ...

of New Zealand.

Ecology

Most species of ''Genoplesium'' and ''Corunastylis'' are pollinated by small vinegar flies but ''C. nuda'' is

self-pollinating Self-pollination is a form of pollination in which pollen from the same plant arrives at the stigma of a flower (in flowering plants) or at the ovule (in gymnosperms). There are two types of self-pollination: in autogamy, pollen is transferred t ...

and reproduces solely by seed. It does not seem to require fire before flowering but often appears in disturbed sites.

Conservation

The tiny midge orchid is widespread and common throughout its range, except in Tasmania, where it is listed as "Rare" under the Tasmanian ''

Threatened Species Protection Act 1995 The ''Threatened Species Protection Act 1995'' (TSP Act), is an act of the Parliament of Tasmania that provides the statute relating to conservation of flora and fauna. Its long title is An Act to provide for the protection and management of t ...

''. It is threatened in that state by land clearing, forestry activities and inappropriate fire regimes.

References

External links

* * {{Taxonbar, from=Q15464014 nudum Flora of Australia Flora of New Zealand Plants described in 1853