Halgania

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Lamiids
Ordo: Boraginales

Familia: Boraginaceae
Subfamilia: Ehretioideae
Genus: Halgania
Species: H. andromedifolia – H. argyrophylla – H. bebrana – H. brachyrhyncha – H. corymbosa – H. cyanea – H. erecta – H. glabra – H. gustafsenii – H. integerrima – H. lavandulacea – H. littoralis – H. preissiana – H. rigida – H. sericiflora – H. solanacea – H. tomentosa – H. viscosa
Source(s) of checklist:

Govaerts, R. et al. 2020. Halgania in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2020 Oct 12. Reference page.

Name

Halgania Gaudich., 1829
References
Primary references

Gaudichaud-Beaupré, C. 1826–1830. Voyage autour du Monde, Entrepis par Ordre du Roi, Exécuté sur les Corvettes de S.M. l'Uranie et la Physicienne, pendant les années 1817, 1818, 1819 et 1820. Botanique. Imprimerie Royale. 522 pp. BHL Reference page. : 448

Links

Govaerts, R. et al. 2020. Halgania in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2020 Oct 12. Reference page.
International Plant Names Index. 2020. Halgania. Published online. Accessed: Oct 12 2020.
Tropicos.org 2020. Halgania. Missouri Botanical Garden. Published on the internet. Accessed: 2020 Oct 12.
Catalogue of Life: 2021 Annual Checklist

Vernacular names

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 andromedifolia

Halgania erecta

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.[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]
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 species are also absent from temperate and tropical areas.
Selected species

Halgania anagalloides Endl.
Halgania andromedifolia Behr & F.Muell. – Lavender halgania, smooth halgania
Halgania argyrophylla Diels
Halgania bebrana Oldfield & F.Muell.
Halgania brachrhyncha Peter G.Wilson
Halgania corymbosa Lindl.
Halgania cyanea Lindl. – Rough halgania
Halgania erecta Ewart & B.Rees
Halgania glabra J.M.Black
Halgania gustafsenii F.Muell.
Halgania integerrima Endl.
Halgania lavandulacea Endl. – Blue bush
Halgania littoralis Gaudich.
Halgania preissiana Lehm.
Halgania rigida S.Moore
Halgania sericiflora Benth.
Halgania solanacea F.Muell.

References

Holstein, N.; Gottschling, M. (2017). "Flowers of Halgania (Ehretiaceae, Boraginales) are set up for being buzzed and the role of intertwining anther trichomes". Flora. 240: 7–15. doi:10.1016/j.flora.2017.12.005.

Holstein, N.; Gottschling, M. (2018). "Waking sleeping beauties: a molecular phylogeny and nomenclator of Halgania (Ehretiaceae, Boraginales)". Australian Systematic Botany. 31 (2): 107–119. doi:10.1071/SB17017.

Wikimedia Commons has media related to Halgania.
Wikispecies has information related to Halgania.

New South Wales Flora online: Halgania
FloraBase: the Western Australian Flora: Halgania
What's Its Name?
Association of Societies for Growing Australian Plants (ASGAP): Halganea cyanea