''Acacia cretacea'', also known as chalky 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 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 ...

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 ...

Description

The shrub or small tree usually has a single stem and can grow to a height of and has a spindly habit with an open crown. It has smooth grey or reddish-brown bark found on the on lower trunk. The grey to medium green coloured

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 have a narrowly elliptic to narrowly oblanceolate shape with a length of up to around and a width of . It blooms intermittently between July and January producing

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 containing 5 to 14 spherical coloured flower-heads. The flower-heads have a diameter of and contain 35 to 45 densely packed lemon yellow to golden yellow coloured flowers. The straight to slightly curved pale brown coloured

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 that form after flowering have a length of up to and a width of and contain black, oblong to ovoid shaped seeds with a length of around and a width of .

Taxonomy

The species was first formally described by the botanists

Bruce Maslin Bruce Roger Maslin (born 3 May 1946) is an Australian botanist, known for his work on ''Acacia'' taxonomy. Born in Bridgetown, Western Australia, he obtained an honours degree in botany from the University of Western Australia in 1967, then to ...

and D. J. E. Whibley in 1987 as part of the work ''The taxonomy of some South Australian Acacia section Phyllodineae species (Leguminosae: Mimosoideae)'' as published in the journal ''

Nuytsia ''Nuytsia floribunda'' is a hemiparasitic tree found in Western Australia. The species is known locally as moodjar and, more recently, the Christmas tree or Western Australian Christmas tree. The display of intensely bright flowers during the ...

''. It was reclassified as ''Racosperma cretaceum'' 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 the genus ''Acacia'' in 2005. 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 ...

is taken from the

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 ''cretaceus'' which means ''chalk white'' in reference to the chalky coloured branchlets, flowers and seed pods. It belongs to the ''

Acacia microbotrya ''Acacia microbotrya'', commonly known as manna wattle or gum wattle, is a shrub or tree belonging to the genus ''Acacia'' and the subgenus ''Phyllodineae'' that is native to Western Australia. The Noongar peoples know the tree as Badjong, Galya ...

'' group of wattles found on the Eye peninsula. It is also closely related to ''

Acacia toondulya ''Acacia toondulya'' is a tree belonging to the genus ''Acacia'' and the subgenus ''Phyllodineae'' native to southern Australia. Description The tree typically grows to a height of and has an erect and wispy habit. The glabrous branchlets are c ...

'' and similar in appearance to '' Acacia gillii''.

Distribution

It is found on the southern and eastern sides of the

Eyre Peninsula The Eyre Peninsula is a triangular peninsula in South Australia. It is bounded by the Spencer Gulf on the east, the Great Australian Bight on the west, and the Gawler Ranges to the north. Originally called Eyre’s Peninsula, it was named aft ...

in South Australia on sandplains and gently undulating hills to the north of Cowell where it grows in red sandy soils as a part of mallee and low shrubland communities. The wattle is commonly associated with ''

Eucalyptus incrassata ''Eucalyptus incrassata'', commonly known as the lerp mallee, yellow mallee, ridge fruited mallee or rib fruited mallee, is a species of mallee that is endemic to southern Australia. It has smooth bark, sometimes with rough, ribbony bark near ...

'', ''

Melaleuca uncinata ''Melaleuca uncinata'', commonly known as broombush, broom honeymyrtle or brushwood, is a plant in the paperbark family native to southern Australia. It is harvested from the wild, and grown in plantations, for broombush fencing. The Noongar nam ...

'' and ''

Triodia irritans ''Triodia irritans'' is a species of plant that forms low and dense mounds of tough grassy vegetation. It is found on sandplains in arid regions of southern and central Australia. The species was first described by Robert Brown in 1810. A comm ...

''. It is restricted to an area approximately and has an estimated population a few hundred to 5,000 individual plants. The shrub also situated on roadsides and in adjacent farming land.

References

{{Taxonbar, from=Q15289843 cretacea Flora of South Australia Taxa named by Bruce Maslin Plants described in 1987

Description

Taxonomy

Distribution

See also

References