Triunia | |
---|---|
Triunia youngiana | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Proteales |
Family: | Proteaceae |
Subfamily: | Grevilleoideae |
Tribe: | Roupaleae |
Genus: | Triunia L.A.S.Johnson & B.G.Briggs (1975) [1] |
Type species | |
Triunia youngiana |
Triunia is a genus of medium to tall shrubs or small trees found as understorey plants in rainforests of eastern Australia. Members of the plant family Proteaceae, they are notable for their poisonous fleshy fruits or drupes. Only one species, T. youngiana, is commonly seen in cultivation.
Lawrie Johnson and Barbara G. Briggs described the genus Triunia in their 1975 monograph "On the Proteaceae: the evolution and classification of a southern family". [2] The group of species in this genus was previously recognised as a subgenus, Macadamiopsis, of Helicia by Hermann Sleumer in 1955. [3] T. youngiana was made the type species. This plant had originally been described in 1864 as Helicia youngiana before being transferred to the genus Macadamia .
They initially placed the genus in its own subtribe, Triuniinae, within the tribe Helicieae. [4] More recently, the genus has been placed in the tribe Roupaleae, [5] Its closest relative is Eucarpha , [6] from New Caledonia.
The members of the genus grow as shrubs to small trees, with simple green obovate to elliptical leaves and new growth covered in reddish hairs. The flowers are fragrant and arranged in terminal racemes. Flowers are followed by small round red fruit, which are highly toxic. [4] The seeds are round. [5]
The four species grow naturally only in eastern Australia between Dorrigo in mid-northern New South Wales and the Wet Tropics rainforests region of north-eastern Queensland. They grow in uplands and mountains rainforests, [3] where they form part of the understorey. [4] Two species grow naturally in south-eastern Queensland and one of them grows further southwards through to north-eastern New South Wales. [3] Two other species are only known to grow about 1,500 km (930 mi) to the north in the uplands and mountains rainforests of the Wet Tropics region of north-eastern Queensland. [3]
In cultivation, all four species grow into garden shrubs with attractive foliage, flowers and fruit, and can tolerate heavy shade to full sun. They require fair to good soil drainage and can be propagated by seed or cutting. [4]
Xylomelum is a genus of six species of flowering plants, often commonly known as woody pears, in the family Proteaceae and are endemic to Australia. Plants in this genus are tall shrubs or small trees with leaves arranged in opposite pairs, relatively small flowers arranged in spike-like groups, and the fruit a woody, more or less pear-shaped follicle.
Floydia is a monotypic genus of plants in the macadamia family Proteaceae which is endemic to Australia. The sole described species is Floydia praealta, commonly known as the ball nut. It is a somewhat rare tree found only growing in the rainforests of southeastern Queensland and northeastern New South Wales. The tree has a superficial resemblance to the closely related Macadamia and could be confused with them. The fruit of F. praealta is poisonous.
Athertonia is a monotypic genus of plants in the family Proteaceae. The sole described species is Athertonia diversifolia, commonly known as Atherton oak, athertonia, creamy silky oak or white oak. It is endemic to a small part of the Wet Tropics of Queensland, Australia. A relative of the macadamia, it has potential in horticulture and the bushfood industry.
Buckinghamia is a genus of only two known species of trees, belonging to the plant family Proteaceae. They are endemic to the rainforests of the wet tropics region of north eastern Queensland, Australia. The ivory curl flower, B. celsissima, is the well known, popular and widely cultivated species in gardens and parks, in eastern and southern mainland Australia, and additionally as street trees north from about Brisbane. The second species, B. ferruginiflora, was only recently described in 1988.
Helicia is a genus of 110 species of trees and shrubs, constituting part of the plant family Proteaceae. They grow naturally in rainforests throughout tropical South and Southeast Asia, including India, Sri Lanka, Indochina, Peninsular Malaysia to New Guinea and as far south as New South Wales.
Gymnostoma is a genus of about eighteen species of trees and shrubs, constituting one of the four genera of the plant family Casuarinaceae. The species grow naturally in the tropics, including at high elevations having temperate climates, in forests in the region of the western Pacific Ocean and Malesia. In New Caledonia, published botanical science describes eight species found growing naturally, which botanists have not found anywhere else (endemics). Other species are native to Borneo, Sumatra, Maluku, and New Guinea, and one endemic species each in Fiji and the Wet Tropics of Queensland, Australia.
Xylomelum cunninghamianum is a species of flowering plant in the family Proteaceae and is endemic to eastern Australia. It is a shrub or small tree with narrow elliptic to lance-shaped leaves with toothed edges when young, groups of flowers covered with brownish hairs and oval fruit densely covered with velvety rust-coloured to grey hair.
Hollandaea is a small genus of plants in the family Proteaceae containing four species of Australian rainforest trees. All four species are endemic to restricted areas of the Wet Tropics of northeast Queensland.
Placospermum is a genus of a single species of large trees, constituting part of the plant family Proteaceae. The species Placospermum coriaceum is endemic to the rainforests of the wet tropics region of northeastern Queensland, Australia. Common names include rose silky oak and plate-seeded oak.
Sphalmium is a monotypic genus of flowering plants in the protea family. The only species, Sphalmium racemosum, is a large forest tree. Common names include satin silky oak, mystery oak, Mt Lewis oak, poorman's fishtail oak and buff silky oak.
Lasjia is a genus of six species of trees of the family Proteaceae. Three species grow naturally in northeastern Queensland, Australia and two species in Sulawesi, Indonesia. Descriptively they are the tropical or northern macadamia trees group. Lasjia species characteristically branched compound inflorescences differentiate them from the Macadamia species, of Australia, which have characteristically unbranched compound inflorescences and only grow naturally about 1,000 km (620 mi) further to the south, in southern and central eastern Queensland and in northeastern New South Wales.
Helicia ferruginea, commonly named hairy honeysuckle or rusty oak, is a species of rainforest trees, of eastern Australia, from the flowering plant family Proteaceae.
Helicia lewisensis is a species of rainforest trees, of northeastern Queensland, Australia, from the flowering plant family Proteaceae. It is endemic to the northern upland rainforests of the Wet Tropics region, from about 900 to 1,330 m altitude.
Helicia grayi, also named Gray's silky oak, is a species of rainforest trees, of northeastern Queensland, Australia, from the flowering plant family Proteaceae.
Helicia lamingtoniana, also named Lamington's silky oak, is a species of rainforest trees, of northeastern Queensland, Australia, from the flowering plant family Proteaceae.
Helicia recurva is a species of rainforest trees, of northeastern Queensland, Australia, from the flowering plant family Proteaceae.
Helicia blakei, also named Blake's silky oak, is a species of rainforest tree, of northeastern Queensland, Australia, from the flowering plant family Proteaceae.
Helicia nortoniana, also named Norton's silky oak, is a species of rainforest trees, of northeastern Queensland, Australia, from the flowering plant family Proteaceae.
Donald Bruce Foreman was an Australian botanist who worked on the Monimiaceae and Proteaceae of Australia. He also helped with the editing of selected Flora of Victoria and Flora of Australia Volumes.
Buckinghamia ferruginiflora, also known as Noah's oak or spotted oak, is a species of rainforest tree in the protea family, one of two in the genus that is endemic to the Wet Tropics of Queensland, north-eastern Australia. Although the tree's differences from its congener had been known since the 1970s, it was only formally described by Donald Foreman and Bernard Hyland in 1988 in the journal Muelleria.