Brachyscome
Encyclopedia
Brachyscome is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of around 70 species of mostly annual
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

 and perennial herbs and a few subshrubs in the daisy family Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

. 65 of these are endemic to Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, the remainder being found in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 and New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...

. They have typical "daisy
Bellis perennis
Bellis perennis is a common European species of Daisy, often considered the archetypal species of that name. Many related plants also share the name "Daisy", so to distinguish this species from other daisies it is sometimes qualified as Common Daisy, Lawn Daisy or occasionally English daisy. It is...

" flower heads with showy ray florets in shades of white, pink, mauve, violet or blue, surrounding a usually narrow group of yellow disk florets. The leaves are often dissected to varying degrees but may be linear
Linear
In mathematics, a linear map or function f is a function which satisfies the following two properties:* Additivity : f = f + f...

 or spathulate. In growth habit they vary between plants with a rosette of basal leaves and more-or-less leafless flower scape
Scape (botany)
In botany, scapes are leafless flowering stems that rise from the ground. Scapes can have a single flower or many flowers, depending on the species....

, and those with mostly cauline leaves and often prostrate stems.

The genus is distinguished from other genera in tribe
Tribe
A tribe, viewed historically or developmentally, consists of a social group existing before the development of, or outside of, states.Many anthropologists use the term tribal society to refer to societies organized largely on the basis of kinship, especially corporate descent groups .Some theorists...

 Astereae
Astereae
Astereae is a tribe of plants in the family Asteraceae that includes annuals, biennials, perennials, subshrubs, shrubs and trees. Plants within the tribe are present nearly worldwide divided into 170 genera and more than 2,800 species...

 mainly by the structure of its tiny fruits commonly referred to as "achenes" but more accurately termed cypselas. They are more-or-less club shaped though usually incurved and flattened to varying degrees, and often with a membranous rim or "wing" around the perimeter that is sometimes crenate or ciliate
Ciliate
The ciliates are a group of protozoans characterized by the presence of hair-like organelles called cilia, which are identical in structure to flagella but typically shorter and present in much larger numbers with a different undulating pattern than flagella...

; the pappus
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...

 is very short, well under 1 mm in length in most species.

Brachyscome species are found in a wide range of habitats, though most prolific and diverse on Australia's inland plains, which is where most of the annual species are found. They have also diversified in montane and alpine habitats in south-eastern Australia and New Zealand.

One of the annual plains species, Brachyscome dichromosomatica is remarkable for its extraordinarily low chromosome count. In plants of this species n=2, though some plants have 1, 2 or 3 additional large B chromosomes.

Henri Cassini published the genus name Brachyscome in 1816, forming the name from classical Greek brachys, "short" and kome, "hair", referring to the very short pappus hairs. However the combining form of brachys in Greek compound words is brachy- and in a later publication Cassini corrected the spelling to Brachycome. There has been a long-running debate among Australian taxonomists as to whether Cassini's corrected spelling is admissible under the International Code of Botanical Nomenclature, the hardline prioritists insisting on Brachyscome while those favoring stability and adherence to conventional orthography continued until recently to use the spelling Brachycome. A proposal to conserve the genus name with the latter spelling was put forward but rejected in 1993 by the ICBN's Committee for Spermatophyta, on the grounds that conservation was unnecessary. This possibly left open the question of whether Brachyscome may be corrected to Brachycome under the orthography clauses of the ICBN. Nowadays all Australian botanical institutions have adopted the spelling Brachyscome.

Cultivation

The species most commonly known to horticulture
Horticulture
Horticulture is the industry and science of plant cultivation including the process of preparing soil for the planting of seeds, tubers, or cuttings. Horticulturists work and conduct research in the disciplines of plant propagation and cultivation, crop production, plant breeding and genetic...

 is Brachyscome iberidifolia
Brachyscome iberidifolia
Brachyscome iberidifolia, the Swan River Daisy is an annual herb found in Western Australia. Occupying a wide range, the species spreads out as fields. The Bellis daisy form and colours were familiar to Europeans when discovered and they have since become a popular garden plant...

, the Swan River Daisy, an annual often sold in seed packets. B. multifida
Brachyscome multifida
Brachyscome multifida is a perennial herb in the family Asteraceae. Common names include Cut-leaved Daisy, Rocky Daisy, and Hawkesbury Daisy. The species is endemic to Australia.-Description:...

is sold as a rock garden
Rock Garden
The Rock Garden or Rock Garden of Chandigarh is a Sculpture garden in Chandigarh, India, also known as Nek Chand's Rock Garden after its founder Nek Chand, a government official who started the garden secretly in his spare time in 1957. Today it is spread over an area of forty-acres , it is...

 or border plant, as are some hybrid cultivars such as 'Break o' Day' and 'Happy Face'.

Species

Species include:
  • Brachyscome chrysoglossa
    Brachyscome chrysoglossa
    Brachyscome chrysoglossa is a perennial herb from Australia in the family Asteraceae. The species is endemic to Australia. -Description:...

    - Yellow-tongue Daisy
  • Brachyscome ciliaris
    Brachyscome ciliaris
    Brachyscome ciliaris, commonly known as Variable Daisy, is a small bushy perennial herb with a prominent flower, which occurs throughout most of temperate Australia-Description:It grows as a bushy perennial herb up to 45 centimetre in height...

    - Variable Daisy
  • Brachyscome iberidifolia
    Brachyscome iberidifolia
    Brachyscome iberidifolia, the Swan River Daisy is an annual herb found in Western Australia. Occupying a wide range, the species spreads out as fields. The Bellis daisy form and colours were familiar to Europeans when discovered and they have since become a popular garden plant...

    - Swan River Daisy
  • Brachyscome multifida
    Brachyscome multifida
    Brachyscome multifida is a perennial herb in the family Asteraceae. Common names include Cut-leaved Daisy, Rocky Daisy, and Hawkesbury Daisy. The species is endemic to Australia.-Description:...

    - Cut-leaved Daisy, Rock Daisy, or Hawkesbury Daisy
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