''Prostanthera discolor'' is a species of flowering plant in the family

Lamiaceae The Lamiaceae ( ) or Labiatae are a family of flowering plants commonly known as the mint, deadnettle or sage family. Many of the plants are aromatic in all parts and include widely used culinary herbs like basil, mint, rosemary, sage, savo ...

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 els ...

to a small area of New South Wales. It is an open, erect, strongly aromatic shrub with lance-shaped to oblong leaves, and deep mauve to purple flowers with darker spots inside.

Description

''Prostanthera discolor'' is an open, erect, aromatic, often compact shrub that typically grows to a height of and has hairy,

glandular In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

branches. The leaves are dull, dark green, paler on the lower side, mostly

glabrous Glabrousness (from the Latin '' glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part o ...

, lance-shaped to more or less oblong, long and wide on a petiole long. The flowers are arranged singly in the upper leaf axils with

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 ...

about long at the base. 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 The term ''sepalum'' was coined ...

s are long and form a tube wide with two lobes, the upper lobe long. The petals are deep mauve to purple with darker markings inside the petal tube, and long. Flowering occurs from September to October.

Taxonomy and naming

''Prostanthera discolor'' was first formally described in 1896 by

Richard Thomas Baker Richard Thomas Baker (1 December 1854 – 14 July 1941) was an Australian economic botanist, museum curator and educator. Early life Baker was born in Woolwich, England, son of Richard Thomas Baker, a blacksmith, and his wife Sarah, née Colkett ...

in ''

Proceedings of the Linnean Society of New South Wales The Linnean Society of New South Wales promotes ''the Cultivation and Study of the Science of Natural History in all its Branches'' and was founded in Sydney, New South Wales (Australia) in 1874 and incorporated in 1884. History The Society succ ...

''.

Distribution and habitat

This mint bush grows in forest in gullies, often in rocky sites in the

Sandy Hollow Sandy Hollow is a small rural town in New South Wales, Australia in Muswellbrook Shire. The town is located on the Golden Highway in the far west of the Upper Hunter Region, about 260 km north of Sydney. It is located around halfway bet ...

– Merriwa district.

Conservation status

This mintbush is listed 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 New South Wales Government '' Biodiversity Conservation Act 2016''. In the year 2000, the entire population of the species was estimated to be 110 individuals. The main threats to the species include

eutrophication Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytopla ...

of nearby streams, grazing by goats and the species' small population size.

References

{{Taxonbar, from=Q15355274 discolor Flora of New South Wales Lamiales of Australia Plants described in 1896 Taxa named by Richard Thomas Baker