Waterhousea is a genus of 4 species of small 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 myrtle family Myrtaceae

Myrtaceae

The Myrtaceae or Myrtle family are a family of dicotyledon plants, placed within the order Myrtales. Myrtle, clove, guava, feijoa, allspice, and eucalyptus belong here. All species are woody, with essential oils, and flower parts in multiples of four or five...

. They are 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...

, along the eastern coast in 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...

 and 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...

. The genus is a relatively new creation, being split off from Syzygium

Syzygium

Syzygium is a genus of flowering plants that belongs to the myrtle family, Myrtaceae. The genus comprises about 1100 species, and has a native range that extends from Africa and Madagascar through southern Asia east through the Pacific...

The most common species, Waterhousea floribunda

Waterhousea floribunda

Waterhousea floribunda is a rainforest tree of eastern Australia. It grows along streams from the Williams River near Dungog to Mackay in central eastern Queensland. Known as the Weeping Lilli Pilli, this tree is widely planted as an ornamental. Planted trees from 1827 may be seen at the Royal...

is a widely grown street tree and is known as the weeping lilly pilly.

Waterhousea species are used as food plants by the larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e of some Lepidoptera

Lepidoptera

Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 species including Aenetus eximia

Aenetus

Aenetus is a genus of moths of the family Hepialidae. There are 24 described species found in Indonesia, New Guinea, New Caledonia, Australia and New Zealand. Most species have green or blue forewings and reddish hindwings but some are predominantly brown or white...

.

Cultivars

Waterhousea floribunda 'Sweeper' is a cultivar with a weeping habit and lush green new growth and a ripple in the leaves. It grows to a height of 10m x 5-8m wide and produces clusters of white flowers in summer. It will grow in full sun to part shade and has and will tolerate light frosts in cool climates.