''Acacia arcuatilis'' is a shrub belonging to the genus ''
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 ...
'' and the subgenus ''Juliflorae'' that 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 south western parts of
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
The rounded spreading shrub can grow to a height of .
[ The sericeous branchlets have red-brown or yellow-brown resin-ribs at the extremities. Like most species of ''Acacia'' 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. The evergreen shallowly to strongly incurved phyllodes occasionally curl back to a full circle. The grey-green and terete phyllodes have a length of and a diameter of and are hairy in the furrows between the nerves. There are usually eight wide and flat topped nerves per face.[ The simple ]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 usually occur in pairs in the axil
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, st ...
s and have spherical flower-heads with a diameter of and contain 10 to 22 golden coloured flowers. Following flowering thinly coriaceous 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 for that have a linear shape but are slightly raised over and constricted between each of the seeds. The straight to slightly curved pods have a length of as much as and a width of and have hairs on the faces and wide margins. The seeds inside the pods are arranged longitudinally and are glossy and mottle with an elliptic shape with a length of with a conical aril
An aril (pronounced ), also called an arillus, is a specialized outgrowth from a seed that partly or completely covers the seed. An arillode or false aril is sometimes distinguished: whereas an aril grows from the attachment point of the see ...
that is about as long as the seed.[
]
Distribution
It is native to areas of the Wheatbelt and the Great Southern regions of 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 ...
.[ The bulk of the population is found around Bindi Bindi in the north down to around Ongerup in the south and as far east as Hyden where is most often a part of open mallee scrub and less frequently open heath communities.
]
See also
* List of ''Acacia'' species
References
{{Taxonbar, from=Q15289759
arcuatilis
Acacias of Western Australia
Plants described in 1999
Taxa named by Bruce Maslin