''Prostanthera rhombea'', commonly known as sparkling mint-bush, is a 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, savory ...

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 disjunct areas of south-eastern Australia. It is an openly-branched shrub with strongly aromatic branches, circular to heart-shaped leaves and mauve or bluish flowers.

Description

''Prostanthera rhombea'' is an openly-branched shrub that typically grows to a height of and has strongly aromatic branches that are covered with

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 ...

hairs. The leaves are more or less round to broadly heart-shaped with the edges rolled downwards, long and wide on a petiole long, the leaves with both glandular hairs and

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 ...

glands. The flowers are arranged singly in leaf axils near the ends of branchlets 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 ...

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 b ...

s are long, forming a tube long with two lobes, the upper lobe about long. The petals are long and mauve or bluish, often with white tips.

Taxonomy

''Prostanthera rhombea'' was first formally described in 1810 by Robert Brown in his treatise ''

Prodromus Florae Novae Hollandiae et Insulae Van Diemen ''Prodromus Florae Novae Hollandiae et Insulae Van Diemen'' (Prodromus of the Flora of New Holland and Van Diemen's Land) is a flora of Australia written by botanist Robert Brown and published in 1810. Often referred to as ''Prodromus Flora Novae ...

''.

Distribution and habitat

Sparkling mint-bush grows in rainforest and forest, often in gullies or near streams, mainly from

Port Macquarie Port Macquarie is a coastal town in the local government area of Port Macquarie-Hastings. It is located on the Mid North Coast of New South Wales, Australia, about north of Sydney, and south of Brisbane. The town is located on the Tasman Sea co ...

to the

Nepean River Nepean River (Darug: Yandhai), is a major perennial river, located in the south-west and west of Sydney, New South Wales, Australia. The Nepean River and its associated mouth, the Hawkesbury River, almost encircles the metropolitan region of ...

in New South Wales and in low heath and woodland in rocky places in three isolated areas in Victoria - near Licola, Mount Timbertop near

Mansfield Mansfield is a market town and the administrative centre of Mansfield District in Nottinghamshire, England. It is the largest town in the wider Mansfield Urban Area (followed by Sutton-in-Ashfield). It gained the Royal Charter of a market tow ...

and

Mount Buffalo Mount Buffalo is a mountain plateau of the Australian Alps and is within the Mount Buffalo National Park in Victoria, Australia. It is located approximately northeast of Melbourne. It is noted for its dramatic scenery. The summit of the highes ...

in Victoria.

References

{{Taxonbar, from=Q15355478 rhombea Flora of New South Wales Flora of Victoria (state) Lamiales of Australia Plants described in 1810 Taxa named by Robert Brown (botanist, born 1773)