''Diuris pedunculata'', commonly known as the small snake 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. Along with the Asteraceae, they are one of the two largest families of flowering ...

which is

endemic Endemism is the state of a species being found 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 found elsew ...

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 ...

. It usually has two leaves at its base and one or two yellow and orange flowers with purple markings. It originally occurred in scattered populations between

Tenterfield Tenterfield is a regional town in New South Wales, Australia. At the , Tenterfield had a population of 4,066. Tenterfield's proximity to many regional centres and its position on the route between Sydney and Brisbane led to its development as a ...

and the

Hawkesbury River The Hawkesbury River, or Hawkesbury-Nepean River, is a river located northwest of Sydney, New South Wales, Australia. The Hawkesbury River and its associated main tributary, the Nepean River, almost encircle the metropolitan region of Sydney. ...

but because of habitat loss is now only known from the New England Tableland.

Description

''Diuris pedunculata'' is a

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 growing ...

ous,

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

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 two erect, linear to thread-like leaves long and wide. One or two pale yellow flowers with an orange labellum, wide are borne on a flowering stem tall. 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 b ...

is narrow egg-shaped, angled upwards, long and 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 cons ...

sepals are lance-shaped with the narrower end towards the base, long, about wide and angled downwards. 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 narrow elliptic, long, wide, spread apart from each other and droop downwards on a dark coloured stalk long. The labellum is long and has three lobes. The centre lobe is broadly egg-shaped, wide and the side lobes are triangular, about long and wide. There are between two irregular ridge-like calli long at the base of the mid-line of the labellum. Flowering occurs in August and September.

Taxonomy and naming

''Diuris pedunculata'' was first described in 1810 by Robert Brown and the description was published in his ''

Prodromus Florae Novae Hollandiae et Insulae Van Diemen ''Prodromus Florae Novae Hollandiae et Insulae Van Diemen'' (Prodromus of the Flora of New Holland and Van Diemen's Land) is a flora of Australia written by botanist Robert Brown and published in 1810. Often referred to as ''Prodromus Flora Novae ...

''. 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 ...

(''pedunculata'') 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 of the ...

word meaning "small, slender stalk".

Distribution and habitat

The small snake orchid was originally found in scattered populations between Tenterfield and the Hawkesbury River but is now only known mostly from areas around

Armidale Armidale is a city in the Northern Tablelands, New South Wales, Australia. Armidale had a population of 24,504 as of June 2018. Estimated resident population, 30 June 2018. It is the administrative centre for the Northern Tablelands region. It ...

Uralla Uralla is a town on the Northern Tablelands, New South Wales, Australia. The town is located at the intersection of the New England Highway and Thunderbolts Way, north of Sydney and about south west of the city of Armidale. At the , the townshi ...

Guyra Guyra is a town situated midway between Armidale and Glen Innes on the Northern Tablelands in the New England region of New South Wales, Australia. It is within Armidale Regional Council and at the 2016 census, it had a population of 1,983. M ...

and Ebor. It grows in moist, grassy places and in open forest. Similar orchids occurring in south-east New South Wales, the

Australian Capital Territory The Australian Capital Territory (commonly abbreviated as ACT), known as the Federal Capital Territory (FCT) until 1938, is a landlocked federal territory of Australia containing the national capital Canberra and some surrounding townships. ...

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...

and

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

have been reinterpreted as '' Diuris subalpina''.

Ecology

This orchid appears use sexual deception, attracting mostly males of the native bee species, '' Halictus lanuginosus'' for pollination, even though the flowers produce nectar and emit a strong scent that attract other insects.

Conservation status

''Diuris pedunculata'' is listed as "endangered" under the Australian Government ''

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cultu ...

'' and under the New South Wales '' Biodiversity Conservation Act 2016''. The main threats to the species include habitat loss and fragmentation, grazing and trampling by livestock, weed invasion and the activities of feral pigs.

References

{{Taxonbar, from=Q10267411 pedunculata Endemic orchids of Australia Orchids of New South Wales Plants described in 1810 Endemic flora of Western Australia Taxa named by Robert Brown (botanist, born 1773)