Synoum is a monotypic

Monotypic

In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...

 genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of evergreen

Evergreen

In botany, an evergreen plant is a plant that has leaves in all seasons. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.There are many different kinds of evergreen plants, both trees and shrubs...

 tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

 in the mahogany family, Meliaceae

Meliaceae

The Meliaceae, or the Mahogany family, is a flowering plant family of mostly trees and shrubs in the order Sapindales....

. It is endemic to Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 where it is found along the eastern sub-tropical to tropical coast, usually on the margins of rainforests, in Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

 and New South Wales

New South Wales

New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...

.

The genus was originally described by French naturalist Adrien-Henri de Jussieu

Adrien-Henri de Jussieu

Adrien-Henri de Jussieu was a French botanist.Born in Paris as the son of botanist Antoine Laurent de Jussieu, he received the degree of Doctor of Medicine in 1824 with a treatise of the plant family Euphorbiaceae. When his father retired in 1826, he succeeded him at the Jardin des Plantes; in...

 in 1830.

The only species described is S. glandulosum, known commonly as Scentless Rosewood. It resembles the related Toona

Toona

Toona is a genus of five species of trees in the mahogany family, Meliaceae, native from Afghanistan south to India, and east to North Korea, Papua New Guinea and eastern Australia...

, except that the leaves have 5-9 leaflets, whereas Toona has 8-20. Its fruit is a reddish three-lobed capsule that contains two or three seeds surrounded by a red aril

Aril

An aril is any specialized outgrowth from the funiculus that covers or is attached to the seed. It is sometimes applied to any appendage or thickening of the seed coat in flowering plants, such as the edible parts of the mangosteen and pomegranate fruit, the mace of the nutmeg seed, or the...

. Germination from fresh seed is reliable and relatively fast.