''Acacia papyrocarpa'', commonly known as western myall,
[ is a ]tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
in the family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
native to arid
A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most ar ...
areas of central and western Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
.
Description
Western myall typically grows as a shrub or an upright tree to a height of but can grow as tall as . It has fissured grey coloured bark and a dense spreading to rounded crown. It has pendulous and hairy branchlets. Like most ''Acacia
''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...
'' species, it has phyllode
Phyllodes are modified petioles or leaf stems, which are leaf-like in appearance and function. In some plants, these become flattened and widened, while the leaf itself becomes reduced or vanishes altogether. Thus the phyllode comes to serve the ...
s rather than true leaves. These are greyish-green in colour, straight and flat, between in length and wide. The hairy phyllodes are acuminate with a fine curved and innocuous point that is not rigid and have many closely parallel indistinct nerves.[ It blooms between August and November][ producing rudimentary ]inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
s. The flowers are yellow, and held in spherical clusters that are about in diameter and contain 20 to 25 golden flowers. After flowering thin and flat seed pod
This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnify ...
s form that have a length of about and a width of that are flat with a narrowly oblong shape. The subnitid dark brown seeds inside the pods have a broadly elliptic to ovate shape with a length of .[
]
Taxonomy
The species was first formally described by the botanist George Bentham
George Bentham (22 September 1800 – 10 September 1884) was an English botanist, described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studi ...
in 1864 as part of the work ''Flora Australiensis
''Flora Australiensis: a description of the plants of the Australian Territory'', more commonly referred to as ''Flora Australiensis'', and also known by its standard abbreviation ''Fl. Austral.'', is a seven-volume flora of Australia published be ...
''. It was reclassified as ''Racosperma papyrocarpum'' by Leslie Pedley
Leslie Pedley (19 May 1930 – 27 November 2018)IPNILeslie Pedley/ref> was an Australian botanist who specialised in the genus ''Acacia''. He is notable for bringing into use the generic name ''Racosperma'', creating a split in the genus, which r ...
in 2003 then transferred back to genus ''Acacia'' in 2006. The only other synonyms are ''Acacia sowdeni'' and ''Acacia sowdenii''.
Distribution
It 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 ...
to arid parts of central Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
, it occurs on limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
plains in southern Australia from Paynes Find in 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 ...
eastwards into South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
. There is also an anomalous specimen at Cooper Creek
The Cooper Creek (formerly Cooper's Creek) is a river in the Australian states of Queensland and South Australia. It was the site of the death of the explorers Burke and Wills in 1861. It is sometimes known as the Barcoo River from one of its t ...
in Queensland
)
, nickname = Sunshine State
, image_map = Queensland in Australia.svg
, map_caption = Location of Queensland in Australia
, subdivision_type = Country
, subdivision_name = Australia
, established_title = Before federation
, established_ ...
. A weeping form of the species that grows at Roxby Downs, South Australia
Roxby Downs is a town and locality in the Australian state of South Australia about north of the state capital of Adelaide. The town has a highly transient population of around 4,000 people.
Roxby Downs has many leisure and community faciliti ...
bears the common name water myall.[ It is commonly situated on low limestone rises, saline or clay flats where it grows in calcareous sandy loam or clay soils.][
]
See also
* List of ''Acacia'' species
References
*
{{Taxonbar, from=Q4670981
Flora of South Australia
Acacias of Western Australia
papyrocarpa
Fabales of Australia
Taxa named by George Bentham