''Prostanthera calycina'', the West Coast mintbush, limestone mintbush or red mintbush, is a species of flowering plant that 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 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. Earlier called Eyre's Peninsula, it was named after e ...

in South Australia. It is a small, more or less prostrate shrub with aromatic, elliptic to oblong leaves and red flowers.

Description

''Prostanthera calycina'' is a more or less prostrate shrub that typically grows to a height of about and has more or less cylindrical, hairy branches. The leaves are well-spaced along the branchlets, elliptic to oblong, long and wide on a densely hairy

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

long. The leaves are strongly aromatic when crushed. The flowers are arranged singly in leaf axils on a hairy

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

long. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s are long forming a tube long with two lobes long and wide. The petals are long forming a tube long with two lips. The middle lobe on the lower lip is about long and wide, the side lobes about long. The upper lip has two lobes about long and joined but with a small notch between them. Flowering occurs between September and December.

Taxonomy

''Prostanthera calycina'' was first formally described in 1870 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 ...

from an unpublished description by

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (; 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 Victoria, Australia ...

and the description was published 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 ...

''.

Distribution and habitat

West coast mintbush is only known from the Eyre Peninsula in South Australia where it usually grows on limestone outcrops in mallee vegetation.

Conservation status

West coast mintbush is classified as "vulnerable" under the Australian Government ''

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cult ...

'' and the South Australian Government ''

National Parks and Wildlife Act 1972 Protected areas of South Australia, consisting of protected areas located within South Australia and its immediate onshore waters and which are managed by South Australian Government agencies. As of 2018, South Australia contained 359 separat ...

''. The main threats to the species include grazing,

habitat fragmentation Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological proces ...

and road maintenance.

Use in horticulture

This mintbush is easily propagated from cuttings or by grafting onto '' Prostanthera nivea'' and grows best in dry climates in well drained soil.

References

{{Taxonbar, from=Q7250953 calycina Flora of South Australia Lamiales of Australia Taxa named by Ferdinand von Mueller Taxa named by George Bentham Plants described in 1870