''Halgania'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of small shrubs in the family

Boraginaceae Boraginaceae, the borage or forget-me-not family, includes about 2,000 species of shrubs, trees and herbs in 146, to 156 genera with a worldwide distribution. The APG IV system from 2016 classifies the Boraginaceae as single family of the or ...

. The genus comprises about 20 species that are endemic to Australia. ''Halgania'' is named for

Emmanuel Halgan Emmanuel Halgan (Donges, 31 December 1771 - Paris, 20 April 1852) was a French Navy officer and admiral. Biography Born to the family of a bailiff, Halgan joined the French Royal Navy aged 16. He then served as a lieutenant and first officer ...

, a vice-admiral in the French Navy.

Features

''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 ''Solanum'' is a large and diverse genus of flowering plants, which include three food crops of high economic importance: the potato, the tomato and the eggplant (aubergine, brinjal). It is the largest genus in the nightshade family Solanaceae ...

''-flowers. The five stamens have short filaments and long yellow to yellow-violet anthers. They are connected via intertwining hairs to an anther cone. 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 Buzz pollination or sonication is a technique used by some bees, such as solitary bees to release pollen which is more or less firmly held by the anthers. The anthers of buzz-pollinated plant species are typically tubular, with an opening at only ...

. Fruits are two- or four chambered dry drupes. File:Halgania_andromedifolia_-_Flickr_-_Kevin_Thiele.jpg, ''Halgania andromedifolia'' File:Halgania_erecta_flowers.jpg, ''Halgania erecta'' File:Halgania solanacea - Flickr - Kevin Thiele.jpg, ''Halgania solanacea''

Systematics

''Halgania'' is a genus that only occurs in Australia, its sister group is still unknown. There are three clades in the genus. The ''H. andromedifolia''-clade (''H. andromedifolia'' and ''H. rigida'') occurs exclusively in

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

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 The Northern Territory (commonly abbreviated as NT; formally the Northern Territory of Australia) is an Australian territory in the central and central northern regions of Australia. The Northern Territory shares its borders with Western Aust ...

. Also four-chambered drupes only occur in this group.

Distribution

''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 Nullarbor Plain ( ; Latin: feminine of , 'no', and , 'tree') is part of the area of flat, almost treeless, arid or semi-arid country of southern Australia, located on the Great Australian Bight coast with the Great Victoria Desert to its ...

. The species are also absent from temperate and tropical areas.

Selected species

*'' Halgania anagalloides'' Endl. *'' Halgania andromedifolia''

Behr Behr is a given name and surname that derives from the German ''Bär'' (''bear''). Older forms of the name, ''Bela'' and ''Belo'' (related to the old High German ''Belo''), occur in the Memorbuch. The diminutive forms ''Baeril'' ''(Berel)'' and ' ...

F.Muell. Baron Sir Ferdinand Jacob Heinrich von Mueller, (german: Müller; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Vic ...

– Lavender halgania, smooth halgania *'' Halgania argyrophylla''

Diels Diels is the last name of several people: * Rudolf Diels (1900–1957), German politician * Otto Diels (1876–1954), German scientist noted for his work on the Diels–Alder reaction * Ludwig Diels (1874–1945), German botanist * Hermann Diels ...

*'' Halgania bebrana'' Oldfield &

*'' Halgania brachrhyncha'' Peter G.Wilson *'' Halgania corymbosa''

Lindl. John Lindley FRS (5 February 1799 – 1 November 1865) was an English botanist, gardener and orchidologist. Early years Born in Catton, near Norwich, England, John Lindley was one of four children of George and Mary Lindley. George Lindley ...

*'' Halgania cyanea''

– Rough halgania *'' Halgania erecta'' Ewart & B.Rees *'' Halgania glabra'' J.M.Black *'' Halgania gustafsenii''

*'' Halgania integerrima'' Endl. *'' Halgania lavandulacea'' Endl. – Blue bush *'' Halgania littoralis'' Gaudich. *'' Halgania preissiana''

Lehm. Johann Georg Christian Lehmann (25 February 1792 – 12 February 1860) was a German botanist. Born at Haselau, near Uetersen, Duchy of Holstein, Holstein, Lehmann studied medicine in Copenhagen and Göttingen, obtained a doctorate in medicine ...

*'' Halgania rigida''

S.Moore Spencer Le Marchant Moore (1 November 1850 – 14 March 1931) was an English botanist. Biography Moore was born in Hampstead. He worked at the Royal Botanic Gardens, Kew, from about 1870 to 1879, wrote a number of botanical papers, and then work ...

*'' Halgania sericiflora''

Benth. George Bentham (22 September 1800 – 10 September 1884) was an English botanist, described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studie ...

*'' Halgania solanacea''

References

New South Wales Flora online: ''Halgania''FloraBase: the Western Australian Flora: ''Halgania''
Ehretioideae Boraginaceae genera {{Australia-asterid-stub