''Diuris brumalis'', commonly known as the winter donkey 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 ...

that is endemic to the

south-west The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each se ...

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. It is one of the first species of donkey orchid to flower in Western Australia each year and its flowers have been shown to attract the same insects that pollinate other species, but without offering a food reward.

Description

''Diuris brumalis'' 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 ...

, usually growing to a height of . Two or three leaves emerge at the base of the flowering stem, each leaf long and wide. Between three and fifteen yellow and brown flowers are borne on the flowering stem and each is long and wide. 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 erect, long and wide and the greenish

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 long, about wide and turn downwards. The ear-like

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 erect with a stalk long and a blade long and wide. The labellum has three lobes, the lateral ones long and wide. The middle lobe is wedge-shaped, long and wide. There is a single yellow ridge in the mid-line of the labellum. Flowering occurs from June to August.

Taxonomy and naming

''Diuris brumalis'' was first described in 1991 by David Jones from a specimen collected near Kalamunda and the description was published in ''Australian Orchid Research''. 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 ...

(''brumalis'') 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 "of the shortest day", referring to the winter flowering of this species.

Distribution and habitat

The winter donkey orchid grows in shrubland and forest between Jurien Bay and

Collie Collies form a distinctive type of herding dogs, including many related landraces and standardized breeds. The type originated in Scotland and Northern England. Collies are medium-sized, fairly lightly-built dogs, with pointed snouts. Many ...

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 reli ...

Jarrah Forest Jarrah forest is tall open forest in which the dominant overstory tree is ''Eucalyptus marginata'' (jarrah). The ecosystem occurs only in the Southwest Botanical Province of Western Australia. It is most common in the biogeographic region named in ...

and

Swan Coastal Plain The Swan Coastal Plain in Western Australia is the geographic feature which contains the Swan River as it travels west to the Indian Ocean. The coastal plain continues well beyond the boundaries of the Swan River and its tributaries, as a geol ...

biogeographical regions of Western Australia.

Ecology

The flowers of this orchid resemble those of some ''

Oxylobium ''Oxylobium'', commonly known as shaggy-pea, is a genus of flowering plants in the family Fabaceae all of which are endemic to Australia. Description Oxylobium range in size from prostrate to tall, upright shrubs, mostly with simple, hairy ste ...

'' and ''

Daviesia ''Daviesia'', commonly known as bitter-peas, is a genus of about 130 species of flowering plants in the family Fabaceae, and is endemic to Australia. Plants in the genus ''Daviesia'' are shrubs or small trees with leaves modified as phyllodes or ...

'' species and are visited by the same native bees that pollinate them, even though the orchid does not reward the insects with nectar or pollen.

Conservation

''Diuris brumalis'' is classified as "not threatened" by the Western Australian Government

Department of Parks and Wildlife The Department of Parks and Wildlife (DPaW) was the department of the Government of Western Australia responsible for managing lands described in the ''Conservation and Land Management Act 1984'' and implementing the state's conservation and e ...

References

{{Taxonbar, from=Q3032193 brumalis Endemic orchids of Australia Orchids of Western Australia Endemic flora of Western Australia Plants described in 1991