''Genoplesium nigricans'', commonly known as mallee midge orchid, is a species of

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 ...

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 ...

. It is a terrestrial

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 a single leaf mostly surrounding the stem, and up to 50 tiny, greenish flowers with a deep maroon-coloured labellum and often have a fruity fragrance. Australian authorities use the name ''Corunastylis tepperi'', a widespread species which has been confused with '' Corunastylis nigricans'', a species with purplish brown flowers and which only occurs on

Kangaroo Island Kangaroo Island (, ) is Australia's third-largest island, after Tasmania and Melville Island, Northern Territory, Melville Island. It lies in the state of South Australia, southwest of Adelaide. Its closest point to the mainland is Snapper Poi ...

and the

Eyre Peninsula The Eyre Peninsula is a triangular peninsula in South Australia. It is bounded by the Spencer Gulf on the east, the Great Australian Bight on the west, and the Gawler Ranges to the north. Earlier called Eyre's Peninsula, it was named after e ...

Description

''Genoplesium nigricans'' 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 ...

sympodial In botany, sympodial growth is a bifurcating branching pattern where one branch develops more strongly than the other, resulting in the stronger branches forming the primary shoot and the weaker branches appearing laterally. A sympodium, als ...

. A single long leaf surrounds the stem from the base of the plant to the lowest of the flowers. The leaf is long and wide. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

is a spike with from 5 to 50 crowded, tiny, non- resupinate flowers which are bright green with a dark maroon-coloured to purplish-black labellum. Each flower is pendulous, about wide and long with

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 and

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'' ...

s that do not spread widely. 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 ...

is a broad egg-shape, about long and wide. The two

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 lance-shaped, long and about wide and dished near their base. The petals are egg-shaped, about long and less than wide. The dark-coloured labellum is egg-shaped, about the same size as the petals with a minutely wavy edge. The

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 ...

is narrow egg-shaped and extends almost to the tip of the labellum. 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 ...

, which is below the labellum has wings with a rough surface. Flowering occurs between February and May and the fruit that follows is a non-fleshy,

dehiscent Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that op ...

capsule containing hundreds of seeds.

Taxonomy and naming

In 1880, Otto Temper, a South Australian school teacher, reported to the

Royal Society of South Australia The Royal Society of South Australia (RSSA) is a learned society whose interest is in science, particularly, but not only, of South Australia. The major aim of the society is the promotion and diffusion of scientific knowledge, particularly in re ...

, the discovery he had made of an orchid "in respect of which Baron F. v. Mueller, has done me the honour of naming it ''Prasophyllum Tepperi''". Tepper's description was formalised by

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Victoria, Australia ...

in 1882 with the name published in ''

Systematic Census of Australian Plants The ''Systematic census of Australian plants, with chronologic, literary and geographic annotations'', more commonly known as the ''Systematic Census of Australian Plants'', also known by its standard botanic abbreviation ''Syst. Census Austral. ...

''. In 2002, David Jones and Mark Clements changed the name of ''Prasophyllum tepperi'' to ''Corunastylis tepperi''. The

World Checklist of Selected Plant Families The World Checklist of Selected Plant Families (usually abbreviated to WCSP) was an "international collaborative programme that provides the latest peer reviewed and published opinions on the accepted scientific names and synonyms of selected p ...

lists ''C. tepperi'' as a

synonym A synonym is a word, morpheme, or phrase that means precisely 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 a ...

of ''Genoplesium nigricans''. 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 ...

(''tepperi'') honours Otto Tepper and the epithet ''nigricans'' 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 "blackish". '' Corunastylis nigricans'', a different species, sometimes confused with ''Genoplesium nigricans'' or ''Corunastylis tepperi'', has purplish brown flowers with green markings and a shiny, dark purplish labellum and only occurs in parts of South Australia.

Distribution and habitat

The mallee midge orchid occurs in arid areas of north-western Victoria, mostly in mallee

shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally o ...

and ''

Callitris ''Callitris'' is a genus of coniferous trees in the Cupressaceae (cypress family). There are 16 recognized species in the genus, of which 13 are native to Australia and the other three (''C. neocaledonica, C. sulcata'' and ''C. p ...

woodland A woodland () is, in the broad sense, land covered with woody plants (trees and shrubs), or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunli ...

, and in the

Avon Wheatbelt The Avon Wheatbelt is a bioregion in Western Australia. It has an area of . It is considered part of the larger Southwest Australia savanna ecoregion. Geography The Avon Wheatbelt bioregion is mostly a gently undulating landscape with low rel ...

, Coolgardie, Esperance Plains, Hampton and Mallee biogeographic regions of southern Western Australia. There are also isolated populations in South Australia. It is a very drought and heat tolerant species which is dormant when the soil is hard-packed and dry, growing and flowering in the cooler, wetter autumn months.

Ecology

This species appears to be pollinated by tiny fruit flies which are attracted by the scent of the flower at the same time as other plants, such as ''

Leucopogon ''Leucopogon'' is a genus of about 150-160 species of shrubs or small trees in the family Ericaceae, in the section of that family formerly treated as the separate family Epacridaceae. They are native to Australia, New Zealand, New Caledonia, the ...

'' are flowering.

References

External links

* * {{Taxonbar, from=Q15463536 nigricans Orchids of Australia Flora of Western Australia Plants described in 1880