| Halgania | |
|---|---|
 | |
| Halgania tuberculosa | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Boraginales |
| Family: | Boraginaceae |
| Subfamily: | Ehretioideae |
| Genus: | Halgania Gaudich. |
| Species | |
See text | |
Halgania is a genus of small shrubs in the family Boraginaceae. The genus comprises about 20 species that are endemic to Australia. Halgania is named for Emmanuel Halgan, a vice-admiral in the French Navy.
Halgania species are spreading to erect shrubs or subshrubs up to 1.2 m high. Leaves are simple, alternating along the stem and membranaceous or leathery. The leaf margin is entire or toothed to serrate and often revolute. Herbaceous stems and leaves can be glabrous but also covered with glandular hairs, simple or bifurcating (resembling cleats, "dolabriform") hairs. In some species, the surface is also covered with a viscose layer of exudates.
The flowers have a calyx of five more or less connected sepals. The 5-parted corolla is blue to violet, rarely white and flat or widely cup-shaped, similar to Solanum -flowers. The five stamens have short filaments and long yellow to yellow-violet anthers. They are connected via intertwining hairs to an anther cone. [1] The pollen sacs open into a central channel, through which the style later emerges. Dusty pollen is released through a pore made by beak-like appendage of the anthers through buzz pollination. Fruits are two- or four chambered dry drupes. [2]
Halgania is a genus that only occurs in Australia, its sister group is still unknown. There are three clades in the genus. [2] The H. andromedifolia-clade (H. andromedifolia and H. rigida) occurs exclusively in Western Australia and the sepals are often conspicuously inqually sized. The anther appendage is short. Species of the H. anagalloides-clade are the only ones to have dolabriform hairs, and they occur in all states of Australia. Their anther appendage is of variable size. The H. littoralis-clade contains the type species of the genus. Its members have neither dolabriform hairs, nor inqually sized sepals, and always long anther appendages. All species of the H. littoralis-clade occur in Western Australia or Northern Territory. Also four-chambered drupes only occur in this group. [2]
Halgania species occur in all states of Australia. They grow in well-drained soils and sand in dry climates, except to the hyper-arid regions of the Nullarbor Plain. The species are also absent from temperate and tropical areas.
Myrtaceae, the myrtle family, is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pōhutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All species are woody, contain essential oils, and have flower parts in multiples of four or five. The leaves are evergreen, alternate to mostly opposite, simple, and usually entire. The flowers have a base number of five petals, though in several genera, the petals are minute or absent. The stamens are usually very conspicuous, brightly coloured, and numerous.
Darwinia, sometimes commonly known as mountain bells or simply bells, is a genus of about 70 species of evergreen shrubs in the family Myrtaceae, endemic to southeastern and southwestern Australia. The majority are native to southern Western Australia, but a few species occur in South Australia, New South Wales and Victoria. The genus was named in honour of Erasmus Darwin, grandfather of Charles Darwin by Edward Rudge in 1816. Most darwinias grow to a height of between 0.2 and 3 m, and many are prostrate shrubs. Most have small, simple leaves and the flowers are often grouped together, each flower with five red, white or greenish petals and ten stamens. In many species, the flowers are surrounded by large, colourful bracts, giving rise to their common names.
Hakea is a genus of about 150 species of plants in the Family Proteaceae, endemic to Australia. They are shrubs or small trees with leaves that are sometimes flat, otherwise circular in cross section in which case they are sometimes divided. The flowers are usually arranged in groups in leaf axils and resemble those of other genera, especially Grevillea. Hakeas have woody fruit which distinguishes them from grevilleas which have non-woody fruit which release the seeds as they mature. Hakeas are found in every state of Australia with the highest species diversity being found in the south west of Western Australia.
Heliotropium is a genus of flowering plants traditionally included in the family Boraginaceae s.l., but placed in the family Heliotropiaceae within the Boraginales order, by the Boraginales Working Group.. There are around 325 species in this almost cosmopolitan genus, which are commonly known as heliotropes. They are highly toxic to dogs and cats, as well as to humans.
Commersonia is a genus of twenty-five species of flowering plants in the family Malvaceae. Plants in this genus are shrubs or trees, occurring from Indochina to Australia and have stems, leaves and flowers covered with star-like hairs. The leaves are simple, often with irregularly-toothed edges, the flowers bisexual with five sepals, five petals and five stamens and the fruit a capsule with five valves. The genus underwent a revision in 2011 and some species were separated from Commersonia, others were added from Rulingia.
Dodonaea, commonly known as hop-bushes, is a genus of about 70 species of flowering plants in the soapberry family, Sapindaceae. The genus has a cosmopolitan distribution in tropical, subtropical and warm temperate regions of Africa, the Americas, southern Asia and Australasia, but 59 species are endemic to Australia.
Stenocarpus is a genus of about 22 species of flowering plants in the family Proteaceae. They are trees or shrubs with variably-shaped leaves, zygomorphic, bisexual flowers, the floral tube opening on the lower side before separating into four parts, followed by fruit that is usually a narrow oblong or cylindrical follicle.
Philotheca is a genus of about fifty species of flowering plants in the family Rutaceae. Plants in this genus are shrubs with simple leaves arranged alternately along the stems, flowers that usually have five sepals, five petals and ten stamens that curve inwards over the ovary. All species are endemic to Australia and there are species in every state, but not the Northern Territory.
Lechenaultia is a genus of flowering plants in the family Goodeniaceae, the species native to Australia with one species also occurring in New Guinea. Plants in the genus Lechenaultia are glabrous shrubs or herbs with needle-shaped leaves, more or less sessile flowers with five sepals and five blue, white, or yellow and red petals in two unequal lobes, the fruit an elongated capsule.
Thomasia is a genus of thirty-one species of flowering plants in the family Malvaceae. Plants in this genus are small shrubs that are endemic to the south-west of Western Australia, apart from T. petalocalyx that is native to Victoria and South Australia. The leaves are simple with leaf-like stipules at the base of the petiole, the flowers bisexual with five papery, petal-like sepals, usually five petals and five stamens opposite the petals. The fruit is a capsule covered with star-like hairs.
Billardiera, commonly known as appleberries, snot berries, or bluebell creepers, is a genus of flowering plants in the family, Pittosporaceae and is endemic to Australia. Plants in the genus Billardiera are woody scramblers, climbers or twiners with elliptic, lance-shaped or linear leaves arranged alternately along the stems, the flowers with petals that are joined to form a tube at the base with spreading lobes, and succulent or fleshy fruit.
Acrotriche is a genus of about 18 species of flowering plants in the family Ericaceae, occurring in all states of Australia except the Northern Territory. Plants in the genus Acrotriche are shrubs with hairy branchlets, leaves with more or less parallel veins and small flowers with 5 sepals and petals joined at the base to form a bell-shaped to cylindrical tube with hairs and stamens in the throat.
Calytrix is a genus of about 83 species of flowering plants, commonly known as star flowers, in the family Myrtaceae and is endemic to Australia. Plants in the genus Calytrix are small to large shrubs with small, spreading and more or less round leaves, the flowers arranged singly in leaf axils. The flowers are bisexual with 5 overlapping sepals with a long awn, and many stamens.
Eremaea is a genus of woody shrubs and small trees in the family Myrtaceae and is endemic to the south-west of Western Australia. Little study of the genus as a whole had been undertaken until Roger Hnatiuk researched Eremaea and published a paper in 1993, A revision of the genus Eremaea (Myrtaceae) in Nuytsia. The first species to be described was Eremaea pauciflora in 1837 and by 1964, the number of species known had increased to 12. Hnatiuk recognised 16 species, 5 subspecies and a number of varieties.
Conostylis is a genus of perennial herbs in the Haemodoraceae family, commonly known as cone flowers. All species are endemic to the south west of Western Australia.
Hemigenia is a genus of flowering plants in the mint family, Lamiaceae and is endemic to Australia where most species occur in Western Australia, although some are also found in New South Wales and Queensland. Plants in this genus are shrubs or bushes with simple leaves and tube-shaped flowers with the petals forming two "lips" - the upper one with two lobes and the lower one with three.
Halgania cyanea, commonly known as rough halgania, is a species of flowering plant in the family Boraginaceae. It is a small perennial shrub with dull green leaves, bright blue flowers and is endemic to Australia.
Plectorrhiza, commonly known as tangle orchids, is a genus of three species of flowering plants from the orchid family, Orchidaceae and is endemic to Australia. Orchids in the genus Plectorrhiza are epiphytic or lithophytic herbs with short stems, long, tangled roots, short leathery leaves and small flowers on a short, thin flowering stem. Two species occur in eastern Australia and one is endemic to Lord Howe Island.
Thomasia solanacea is a species of flowering plant in the family Malvaceae and is endemic to the south-west of Western Australia. It is an erect, bushy shrub with egg-shaped leaves, the bases heart-shaped, and racemes of white, cream-coloured or pink to purple flowers.
Halgania brachyrhyncha is a species of flowering plant in the family Boraginaceae. It is a small perennial shrub with blue flowers and grows in New South Wales and Queensland.
