Xylomelum is a 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 six species in the plant family Proteaceae

Proteaceae

Proteaceae is a family of flowering plants distributed in the Southern Hemisphere. The family comprises about 80 genera with about 1600 species. Together with the Platanaceae and Nelumbonaceae they make up the order Proteales. Well known genera include Protea, Banksia, Embothrium, Grevillea,...

. They are native 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...

, growing in the form of tall shrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

s and 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...

s. The genus includes at least two species with the common name woody pear, Xylomelum pyriforme

Xylomelum pyriforme

Xylomelum pyriforme, commonly known as the woody pear, is a tree species in the family Proteaceae. It is endemic to Australia. First documented at Botany Bay by Joseph Banks and Daniel Solander in 1770, it was first described as Banksia pyriformis by German botanist Joseph Gaertner in 1788 in De...

in the eastern states of Australia

Eastern states of Australia

In Australia, the term eastern states refers to the states adjoining the east coast of Australia. These are the mainland states of New South Wales, Queensland and Victoria. The Australian Capital Territory and Jervis Bay Territory, while not states, are also included. The term usually includes the...

, and Xylomelum occidentale

Xylomelum occidentale

Xylomelum occidentale, commonly known as the western woody pear, is a tree species in the family Proteaceae. It is endemic to Western Australia. It was first described by Robert Brown in 1830. The species name is derived from the Latin adjective occidentalis "western"....

in Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

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Fruits

The fruits of Xylomelum are in the form of woody pears. When dried, these pears split down a central division, resulting in two halves. These "pears" are thought to have evolved primarily as a defense against seed predation. However, these woody fruits also provide protection of the seeds from fire. It is therefore likely that this characteristic was reselected in evolution as fire became increasingly important.

Classification

Recent molecular studies have Xylomelum paired as a sister clade

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 with Lambertia

Lambertia

Lambertia is a genus of flowering plants, belonging to the family Proteacea. It is endemic to Australia.The genus was named in 1798 by Sir James Edward Smith in honour of English botanist Aylmer Bourke Lambert....

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