''Acacia costiniana'', commonly known as Costin's wattle, 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 ''Phyllodineae'' that is
endemic to eastern
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 shrub typically grows to a height of and has an erect or weeping or spreading habit.
[ The puberulous branchlets have stipules that are in length. 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 phyllodes appear crowded and are mostly ascending to erect with an asymmetrically ovate to elliptic shape. They are in length and wide with fine, sparse, straight hairs lying flat against the surface. The phyllodes have a slightly excentric midrib and obscure lateral nerves.[ It blooms between August and September][ producing simple or racemose inflorescences that have obloid to subglobular flower-heads that are around in length and contain 14 to 26 golden or rich lemon yellow coloured flowers. After flowering it forms thinly coriaceous seed pods that are velvety with ferruginous to silvery-ferruginous hairs. The pods have a narrowly oblong shape and are uo to in length and wide. The shiny black seeds inside have an ovate to oblong-elliptic shape and are in length with a clavate ]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 ...
.
Taxonomy
The species was first formally described by the botanist Mary Tindale
Mary Douglas Tindale (19 September 1920 – 31 March 2011) was an Australian botanist specialising in pteridology (ferns) and the genera ''Acacia'' and ''Glycine''.
Tindale was born in Randwick, New South Wales, the only child of George Harold Ti ...
in 1980 as part of the work ''Notes on Australian taxa of Acacia'' as published in the journal '' Telopea''. It was reclassified as ''Racosperma costinianum'' in 2003 by Leslie Pedley then transferred back to the genus ''Acacia'' in 2006.
Distribution
It is native to south eastern parts of New South Wales between Captains Flat through to Bombala where it is found on rocky slopes as a part of dry sclerophyll forest and heath communities.[
]
See also
* List of Acacia species
Several Cladistics, cladistic analyses have shown that the genus ''Acacia sensu lato, Acacia'' is not monophyletic. While the subg. ''Acacia'' and subg. ''Phyllodinae'' are monophyletic, subg. ''Aculeiferum'' is not. This subgenus consists of thr ...
References
{{Taxonbar, from=Q9563636
costiniana
Flora of New South Wales
Plants described in 1980