''Oxera'' is a genus of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the family

Lamiaceae The Lamiaceae ( ) or Labiatae are a family (biology), family of flowering plants commonly known as the mint, deadnettle, or sage family. Many of the plants are aromatic in all parts and include widely used culinary herbs like basil (herb), ba ...

native to

Vanuatu Vanuatu ( or ; ), officially the Republic of Vanuatu (; ), is an island country in Melanesia located in the South Pacific Ocean. The archipelago, which is of volcanic origin, is east of northern Australia, northeast of New Caledonia, east o ...

and

New Caledonia New Caledonia ( ; ) is a group of islands in the southwest Pacific Ocean, southwest of Vanuatu and east of Australia. Located from Metropolitan France, it forms a Overseas France#Sui generis collectivity, ''sui generis'' collectivity of t ...

in the western Pacific.Kew World Checklist of Selected Plant Families
/ref>

Description

Species of ''Oxera'' show a variety of growth forms, including

liana A liana is a long-Plant stem, stemmed Woody plant, woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the Canopy (biology), canopy in search of direct sunlight. T ...

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

s and

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

s. The leaves are simple, and are petiolate (on short stalks), except in '' O. sessilifolia'', with entire or occasionally sinuate (wavy) edges. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s are loose

thyrse A thyrse is a type of inflorescence in which the main axis grows indeterminately, and the subaxes (branches) have determinate growth. Gallery File:Syringa Leipzig 2011.jpg, ''Syringa ''Syringa'' is a genus of 12 currently recognized spec ...

s of flowers, growing from leaf axils (axillary) or directly from the stem (

cauliflory Cauliflory is a botanical term referring to plants that flower and fruit from their main stems or woody trunks, rather than from new growth and shoots. It is rare in temperate regions but common in tropical forests. There have been several st ...

). The flowers are large, conspicuous and bisexual; the calyx is actinomorphic (rotationally symmetrical), but the corolla is zygomorphic, sometimes strongly so. Although some species have four

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s in each flower, they are usually reduced in number with two stamens, usually the posterior pair, forming

staminode In botany, a staminode is an often rudimentary, sterile or abortive stamen, which means that it does not produce pollen.Jackson, Benjamin, Daydon; ''A Glossary of Botanic Terms with their Derivation and Accent''; Published by Gerald Duckworth & Co ...

s instead.

Distribution

Twenty of the twenty-one species are found on the island of Grande Terre (the main island of

). Three species occur on the adjacent island of Île des Pins, two on

Lifou Lifou () is a communes of France, commune of France in the Loyalty Islands Province of New Caledonia, Pacific Ocean. Geography Lifou is made up of Lifou Island, the largest and most heavily populated of the Loyalty Islands, its smaller neighbou ...

and one on Maré in the

Loyalty Islands Loyalty Islands Province (, ) is one of the three top-level administrative subdivisions of New Caledonia. It encompasses the Loyalty Islands () archipelago in the Pacific Ocean, located northeast of the New Caledonian mainland of Grande Terre. ...

, and two on

(including one

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

). ''

Oxera vanuatuensis ''Oxera'' is a genus of flowering plants in the family Lamiaceae native to Vanuatu and New Caledonia in the western Pacific. Description Species of ''Oxera'' show a variety of growth forms, including lianas, shrubs and trees. The leaves are simp ...

'' is only known from Vanuatu, where it is only known from cultivated specimens. Villagers on

Pentecost Island Pentecost is one of the 83 islands that make up the Oceania, South Pacific nation of Vanuatu. It lies due north of capital Port Vila. Pentecost is known as in French language, French and in Bislama. The island was known in its native lan ...

(and their descendants on

Maewo Maewo (, in English as and formerly ''Aurora Island'') is an island in Vanuatu in Penama province, 105 km to the east of Espiritu Santo. It is 47 km long, and 6 km wide, with an area of 269 km2. Its highest point is 795 ...

call the tree ''harongmau'', and

propagate Propagation can refer to: *Chain propagation in a chemical reaction mechanism *Crack propagation, the growth of a crack during the fracture of materials *Propaganda, non-objective information used to further an agenda *Reproduction, and other forms ...

the species by planting seeds, transplanting seedlings or taking cuttings. The plant is thought to treat illnesses caused by

black magic Black magic (Middle English: ''nigromancy''), sometimes dark magic, traditionally refers to the use of Magic (paranormal), magic or supernatural powers for evil and selfish purposes. The links and interaction between black magic and religi ...

, and profuse flowering from the trunk is thought to foretell a good harvest of yams.

Species

Twenty-one species are recognised in the genus ''Oxera'', in five informal

species group In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

s: ;''baladica'' group *'' Oxera baladica'' Vieill. *''

Oxera sessilifolia ''Oxera'' is a genus of flowering plants in the family Lamiaceae native to Vanuatu and New Caledonia in the western Pacific. Description Species of ''Oxera'' show a variety of growth forms, including lianas, shrubs and trees. The leaves are simp ...

'' Dubard *'' Oxera subverticillata'' Vieill. *''

'' de Kok –

;''robusta'' group *'' Oxera coriacea'' Dubard *'' Oxera coronata'' de Kok *'' Oxera palmatinervia'' Dubard *'' Oxera robusta'' Vieill. ;''pulchella'' group *'' Oxera balansae'' Dubard – Grande Terre, Île des Pins, Lifou Status iucn EN icon

*'' Oxera brevicalyx'' (Moldenke) de Kok *'' Oxera crassifolia'' Virot Status iucn LC icon

*'' Oxera morierei'' Vieill. *''

Oxera pulchella ''Oxera'' is a genus of flowering plants in the family Lamiaceae native to Vanuatu and New Caledonia in the western Pacific. Description Species of ''Oxera'' show a variety of growth forms, including lianas, shrubs and trees. The leaves are simp ...

'' Labill. Status iucn LC icon

;''sulfurea'' group *'' Oxera gmelinoides'' S. Moore *'' Oxera microcalyx'' Guillaumin *'' Oxera rugosa'' Guillaumin *'' Oxera sulfurea'' Dubard – Grand Terre, Île des Pins, Lifou, Maré ;''macrocalyx'' group *'' Oxera glandulosa'' Vieill. – New Caledonia, Île des Pins *''

Oxera neriifolia ''Oxera'' is a genus of flowering plants in the family Lamiaceae native to Vanuatu and New Caledonia in the western Pacific. Description Species of ''Oxera'' show a variety of growth forms, including lianas, shrubs and trees. The leaves are simp ...

'' (Montrouz.) Beauvis. *'' Oxera macrocalyx'' Dubard Status iucn VU icon

*'' Oxera oreophila'' Guillaumin

Taxonomic history

The genus ''Oxera'' was erected by French voyager and botanist Jacques Labillardière in 1824, based on a single specimen that he had collected in New Caledonia. The closest relative of ''Oxera'' is the genus ''

Faradaya ''Faradaya'' is a genus of plants in the mint family, Lamiaceae, first described in 1865 by Victorian government botanist Ferdinand von Mueller in ''Fragmenta Phytographiae Australiae''. Following a revision of the genera '' Oxera'', ''Clerodendr ...

'', and the two genera were once united as the tribe Oxereae. Collectively, they are the

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to a

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

containing ''

Clerodendrum ''Clerodendrum'' is a genus of flowering plants formerly placed in the family Verbenaceae, but now considered to belong to the Lamiaceae (mint) family. Its common names include glorybower, bagflower, pagoda flower and bleeding-heart. It is curre ...

'' and a number of segregate genera such as '' Kalaharia'', '' Huxleya'', '' Amasonia'' and '' Tetraclea''. Both genera are now treated as members of the subfamily Teucrioideae, following work published by Philip D. Cantino in 1992.

Notes

References

{{Taxonbar, from=Q2705492 Lamiaceae Lamiaceae genera Flora of New Caledonia Flora of Vanuatu Taxonomy articles created by Polbot