''Exostema'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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 Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Rubiaceae Rubiaceae () is a family (biology), family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with Petiole ( ...

. It consists of trees and shrubs,

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the

neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In biogeog ...

, with most of the species occurring in the

West Indies The West Indies is an island subregion of the Americas, surrounded by the Atlantic Ocean, North Atlantic Ocean and the Caribbean Sea, which comprises 13 independent island country, island countries and 19 dependent territory, dependencies in thr ...

Description

''Exostema'' is a genus of neotropical

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 and

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. The flowers have a slender corolla tube with recurved corolla lobes. The stamens are inserted near the base of the corolla tube and exserted well beyond its mouth. The

anther 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 are long and basifixed.

Systematics

The

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

for the genus is ''

Exostema caribaeum ''Exostema'' is a genus of flowering plants in the family Rubiaceae. It consists of trees and shrubs, endemic to the neotropics, with most of the species occurring in the West Indies. Description ''Exostema'' is a genus of neotropical trees and ...

''. It is a tree of

Central America Central America is a subregion of North America. Its political boundaries are defined as bordering Mexico to the north, Colombia to the southeast, the Caribbean to the east, and the Pacific Ocean to the southwest. Central America is usually ...

and the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

. Its

lumber Lumber is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards. Lumber is mainly used for construction framing, as well as finishing (floors, wall panels, window frames). ...

is of limited use. ''Exostema'' was first named by

Christiaan Hendrik Persoon Christiaan Hendrik Persoon (31 December 1761 – 16 November 1836) was a Cape Colony mycologist who is recognized as one of the founders of mycology, mycological Taxonomy (biology), taxonomy. Early life Persoon was born in Cape Colony at ...

as a

subgenus In biology, a subgenus ( subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the ge ...

of ''

Cinchona ''Cinchona'' (pronounced or ) is a genus of flowering plants in the family Rubiaceae containing at least 23 species of trees and shrubs. All are native to the Tropical Andes, tropical Andean forests of western South America. A few species are ...

''.Christiaan Hendrik Persoon. 1805. ''Synopsis plantarum,seu Enchiridium botanicum, complectens enumerationem systematicam specierum hucusque cognitarum /curante''. 1:196. It was first validly published as a genus by

Aimé Bonpland Aimé Jacques Alexandre Bonpland (; 22 August 1773 – 11 May 1858) was a French List of explorers, explorer and botany, botanist who traveled with Alexander von Humboldt in Latin America from 1799 to 1804. He co-authored volumes of the scie ...

in 1807.Alexander von Humboldt and Aimé Bonpland. 1807. ''Plantes équinoxiales recueillies au Mexique :dans l'île de Cuba, dans les provinces de Caracas, de Cumana et de Barcelone, aux Andes de la Nouvelle Grenade, de Quito et du Pérou, et sur les bords du rio-Negro de Orénoque et de la rivière des Amazones''. 1:131. F. Schoell: Paris, France. The generic name is derived from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

words, ''exo'', meaning "outside", and ''stema'', "stamen". As

circumscribed In geometry, a circumscribed circle for a set of points is a circle passing through each of them. Such a circle is said to ''circumscribe'' the points or a polygon formed from them; such a polygon is said to be ''inscribed'' in the circle. * Circum ...

in 2010, ''Exostema'' was probably

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

. Species have since been moved to other genera.

Species

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

accepted the following species: *'' Exostema acuminatum'' Urb. *'' Exostema bicolor'' Poepp. *''

'' (Jacq.) Schult. *'' Exostema coriaceum'' (Poir.) Schult. *'' Exostema glaberrimum'' Borhidi & M.Fernández *'' Exostema lancifolium'' Borhidi & Acuña *''

Exostema nitens ''Exostema'' is a genus of flowering plants in the family Rubiaceae. It consists of trees and shrubs, endemic to the neotropics, with most of the species occurring in the West Indies. Description ''Exostema'' is a genus of neotropical trees and ...

'' Urb. *'' Exostema purpureum'' Griseb. *''

Exostema revolutum ''Exostema'' is a genus of flowering plants in the Family (biology), family Rubiaceae. It consists of trees and shrubs, Endemism, endemic to the neotropics, with most of the species occurring in the West Indies. Description ''Exostema'' is a gen ...

'' Borhidi & M.Fernández *'' Exostema salicifolium'' Griseb. *''

Exostema spinosum ''Exostema'' is a genus of flowering plants in the family Rubiaceae. It consists of trees and shrubs, endemic to the neotropics, with most of the species occurring in the West Indies. Description ''Exostema'' is a genus of neotropical trees and ...

'' (Le Vavass.) Krug & Urb.

References

External links

''Exostema''
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World Checklist of Selected Plant Families''Exostema''
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Index Nominum Genericorum''Exostema''
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Biodiversity Heritage Library''Exostema''
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IPNI''Exostema''
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GRIN taxonomy for plants''Exostema''
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UniProt
{{Taxonbar, from=Q5420696 Rubiaceae genera Taxa named by Aimé Bonpland Taxa named by Alexander von Humboldt Taxonomy articles created by Polbot