''Prostanthera spinosa'', commonly known as spiny mintbush, is a shrub 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 els ...

to south-eastern Australia. It has mauve to white flowers, spiny stems and aromatic foliage.

Description

''Prostanthera spinosa'' is a small, rigid, upright shrub with a scrambling habit mostly semi-prostrate, usually high. The aromatic branches may be sparsely or moderately densely hairy with either upward spreading, straight or curled hairs long, or smooth with a few hairs at the nodes and consistent

decussate Decussation is used in biological contexts to describe a crossing (due to the shape of the Roman numeral for ten, an uppercase 'X' (), ). In Latin anatomical terms, the form is used, e.g. . Similarly, the anatomical term chiasma is named aft ...

spines long. The small leaves are thickly hairy or with occasional hairs, mostly on the petiole. The leaf is narrowly egg-shaped to broadly elliptic or

trullate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regula ...

long, wide and the petiole long. The leaves are darker on the upper surface, paler on the underside, smooth or with firm, spreading hairs below on the midrib and profusely covered with glands. The leaf margins entire or slightly rolled under, underside veins obscure, ending in a rounded apex on a petiole long. Its flowers occur singly in the leaf axils, they are pale mauve to lilac to white with orange-brown streaks or spots on the lower inside petal that is long. The

bracteoles 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 ...

remain to flower maturity are long and wide. Flowering occurs from July to December.

Taxonomy and naming

The species was formally described in 1855 by Victorian Government Botanist

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (german: Müller; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Vic ...

, based on plant material collected from "rocky declivities in springs near the

Grampians The Grampian Mountains (''Am Monadh'' in Gaelic) is one of the three major mountain ranges in Scotland, that together occupy about half of Scotland. The other two ranges are the Northwest Highlands and the Southern Uplands. The Grampian r ...

". The description was published in ''

Hooker's Journal of Botany and Kew Garden Miscellany ''Hooker's Journal of Botany and Kew Garden Miscellany'' was a scientific journal In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. ...

''. 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 ...

(''spinosa'') is derived 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 ...

''spinosus'' meaning "thorny".

Distribution and habitat

Spiny mintbush occurs in the

in rocky locations on shallow, sandy soils. In

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 ...

it is found growing near watercourses mostly in loamy-sand over limestone or sandstone.

References

{{Taxonbar, from=Q15355306 spinosa Flora of South Australia Flora of Victoria (state) Lamiales of Australia Plants described in 1855 Taxa named by Ferdinand von Mueller