''Olearia revoluta'' is a species of flowering plant in the family
Asteraceae
The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae w ...
and 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 the south-west of Western Australia. It is an erect, rounded shrub with linear to oblong leaves with the edges rolled under, and white daisy-like
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.
Description
''Olearia revoluta'' is an erect, rounded shrub that typically grows to a height of and has many branches. The leaves are linear to oblong, long with the edges rolled under, the lower surface woolly-hairy. The heads or daisy-like
"flowers" are arranged in leaf axils and are
sessile
Sessility, or sessile, may refer to:
* Sessility (motility), organisms which are not able to move about
* Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant
* Sessility (medicine), tumors and polyps that ...
or on a short
peduncle with an oval to top-shaped
involucre
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...
at the base. Each head has 4 to 8 white ray
florets
This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...
surrounding 6 to 10 disc florets. Flowering occurs between May and November.
Taxonomy
''Olearia revoluta'' was first described in 1867 by
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 ''
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 ...
'' from specimens collected by
Augustus Oldfield
Augustus Frederick Oldfield (1821–1887) was an English botanist and zoologist who made large collections of plant specimens in Australia.
Oldfield was born on 12 January 1821 in London, England. He made botanical collections in Tasmania, the coa ...
between the
Murchison and southern
Hutt Rivers.
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 ...
(''revoluta'') means "
revolute", referring to the edges of the leaves.
Distribution and habitat
This olearia grows in sand over
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates) ...
, on the sandplains toward
Geraldton
Geraldton (Wajarri: ''Jambinu'', Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West region of the Australian state of Western Australia, north of the state capital, Perth.
At June 2018, Geraldton had an urban population of 37,648. ...
and beyond
Esperance in the
Avon Wheatbelt
The Avon Wheatbelt is a bioregion in Western Australia. It has an area of . It is considered part of the larger Southwest Australia savanna ecoregion.
Geography
The Avon Wheatbelt bioregion is mostly a gently undulating landscape with low reli ...
,
Esperance Plains
Esperance Plains, also known as Eyre Botanical District, is a biogeographic region in southern Western Australia on the south coast between the Avon Wheatbelt and Hampton bioregions, and bordered to the north by the Mallee region. It is a pl ...
,
Geraldton Sandplains
Geraldton (Wajarri: ''Jambinu'', Wilunyu: ''Jambinbirri'') is a coastal city in the Mid West region of the Australian state of Western Australia, north of the state capital, Perth.
At June 2018, Geraldton had an urban population of 37,648. ...
and
Yalgoo bioregions of south-western Western Australia.
Ecology
The seeds are harvested by the
western rosella
The western rosella (''Platycercus icterotis''), or moyadong, is a species of parrot endemic to southwestern Australia. The head and underparts are bright red, and the back is mottled black; a yellow patch at the cheek distinguishes it from oth ...
subspecies ''Platycercus icterotis icterotis''.
References
{{Taxonbar, from=Q15589586
revoluta
Endemic flora of Western Australia
Asterales of Australia
Taxa named by George Bentham
Plants described in 1867