''Genoplesium arrectum'', commonly known as the erect midge orchid and as ''Corunastylis arrecta'' in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, is a small terrestrial

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Orchids are cosmopolitan plants that are found in almost every habitat on Eart ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to south-eastern Australia. It has a single thin leaf fused to the flowering stem and up to twenty small, dark purple flowers. It grows in a

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is ...

and

subalpine Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...

grassland and forest in

Victoria Victoria most commonly refers to: * Queen Victoria (1819–1901), Queen of the United Kingdom and Empress of India * Victoria (state), a state of Australia * Victoria, British Columbia, Canada, a provincial capital * Victoria, Seychelles, the capi ...

and the

Australian Capital Territory The Australian Capital Territory (ACT), known as the Federal Capital Territory until 1938, is an internal States and territories of Australia, territory of Australia. Canberra, the capital city of Australia, is situated within the territory, an ...

Description

''Genoplesium arrectum'' is a terrestrial,

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

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 Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

herb Herbs are a widely distributed and widespread group of plants, excluding vegetables, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal purposes, or for fragrances. Culinary use typically distingu ...

with an underground

tuber Tubers are a type of enlarged structure that plants use as storage organs for nutrients, derived from stems or roots. Tubers help plants perennate (survive winter or dry months), provide energy and nutrients, and are a means of asexual reproduc ...

and a single thin leaf long and fused to the flowering stem with the free part long. Between three and twenty dark purple flowers are crowded along a flowering stem tall and taller than the leaf. The flowers are about long, wide and 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 The fus ...

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 Etymology The term ''sepalum'' ...

is a broad egg shape, about long and wide with hairless edges and dark coloured bands. The

lateral Lateral is a geometric term of location which may also refer to: Biology and healthcare * Lateral (anatomy), a term of location meaning "towards the side" * Lateral cricoarytenoid muscle, an intrinsic muscle of the larynx * Lateral release ( ...

sepals are linear to lance-shaped, about long, wide, stiffly erect and more or less parallel to each other. The

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s are a narrow egg shape, about long and wide with dark coloured bands and hairless edges. The labellum is elliptic to broadly egg-shaped, about long, wide, thick and fleshy with coarse hairs on its edges. There is a narrow egg-shaped

callus A callus (: calluses) 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, b ...

in the centre of the labellum and extending three-quarters of the way to its tip. Flowering occurs in December and January.

Taxonomy and naming

''Genoplesium arrectum'' was first formally described in 1991 by David Jones from a specimen collected near

Omeo Omeo ( ) is a town in Victoria, Australia on the Great Alpine Road, east of Mount Hotham, in the Shire of East Gippsland. At the 2016 census, Omeo had a population of 406. The name is derived from an Aboriginal word for 'mountains' or 'hi ...

and the description was published in ''Australian Orchid Research''. In 2002 Jones and Mark Clements changed the name to ''Corunastylis arrecta''. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

(''arrecta'') is a

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

word meaning "upright", referring to the stiffly erect lateral sepals.

Distribution and habitat

''Genoplesium arrectum'' grows in grassland and grassy forest at altitudes above in north-eastern Victoria and in the Australian Capital Territory.

References

External links

* * {{Taxonbar, from=Q15462876 arrectum Endemic orchids of Australia Orchids of the Australian Capital Territory Orchids of Victoria (state) Plants described in 1991