''Olearia rudis'', commonly known as azure daisy-bush, is a species of flowering plant in the family

Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...

and is

endemic Endemism is the state of a species being found only 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 foun ...

to eastern Australia. It is a usually short-lived shrub with crowded elliptic or egg-shaped leaves, and pale blue, mauve or purple and orange, daisy-like

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

Description

''Olearia rudis'' is a stiff, usually short-lived shrub or subshrub that typically grows to a height of up to about , its branchlets usually bristly-hairy. It has crowded elliptic or egg-shaped leaves with the narrower end towards the base, long and wide. Both surface of the leaves are bristly-hairy, the edges are often serrated, and the base is slightly stem-clasping. The heads or daisy-like "flowers" are arranged singly or in

corymb Corymb is a botanical term for an inflorescence with the flowers growing in such a fashion that the outermost are borne on longer pedicels than the inner, bringing all flowers up to a common level. A corymb has a flattish top with a superficial re ...

s on the ends of branches or in leaf axils on a peduncle and are in diameter. Each head has 40 to 75 pale blue, mauve or purple 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 ...

, the

ligule A ligule (from "strap", variant of ''lingula'', from ''lingua'' "tongue") is a thin outgrowth at the junction of leaf A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above g ...

long, surrounding 60 to 250 orange disc florets. Flowering occurs from July to October and the fruit is a glabrous

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...

, the pappus long.

Taxonomy

This daisy was first formally described in 1837 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 studie ...

who gave it the name ''Eurybia rudis'' in ''

Enumeratio plantarum quas in Novae Hollandiae ora austro-occidentali ad fluvium Cygnorum et in sinu Regis Georgii collegit Carolus Liber Baro de Hügel ''Enumeratio plantarum quas in Novae Hollandiæ ora austro-occidentali ad fluvium Cygnorum et in sinu Regis Georgii collegit Carolus Liber Baro de Hügel'' is a description of the plants collected at the Swan River colony and King George Sound in ...

'' from specimens collected near the Swan River. In 1867, Bentham changed the name to ''Olearia rudis'' 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 b ...

''. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

(''rudis'') means "rough" or "wild".

Distribution and habitat

''Olearia rudis'' grows in mallee and woodland in western New South Wales, north-western Victoria and the south-east of South Australia.

References

{{Taxonbar, from=Q15590415 rudis Asterales of Australia Flora of New South Wales Flora of Victoria (state) Flora of South Australia Plants described in 1837 Taxa named by George Bentham