''Retiniphyllum'' 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
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s in the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Rubiaceae
The Rubiaceae are a 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 interpetiolar stipules a ...
and contains 20
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
.
It is the only genus in the tribe Retiniphylleae. The representatives are shrubs or small trees that grow in white sand soils in tropical South America. They are mainly distributed in the Guayana Region (
Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
) but also occur in the Amazon Basin, the eastern Andes and central and eastern Brasil.
Description
The species exhibit a character that is not common in the family Rubiaceae, viz. the presence of two collateral and pendulous ovules per
locule. The shrubs or trees have apical buds with abundant resin. Each flower is subtended by a bracteole and the corollas are contorted. Stamens are reflexed in anthesis and have basal and apical sterile appendages. Many species also exhibit secondary pollen presentation. The 5-locular ovary contains two ovules per locule. The drupaceous fruits contain pyrenes with one seed due to the abortion of one ovule.
Taxonomy
''Retiniphyllum'' was placed in the subfamily
Rubioideae
Rubioideae Juss., 1789 is a subfamily of flowering plants in the family Rubiaceae and contains about 7600 species in 27 tribes.
Tribes
* Anthospermeae Cham. & Schltdl. ex DC.
* Argostemmateae Bremek. ex Verdc.
* Clarkelleae Deb
* Co ...
in the earliest systems of classification due to the misinterpretation of the bi-ovulated locules.
William Jackson Hooker established the tribe Retiniphylleae in 1873 and included the genera ''Retiniphyllum'' and ''
Kutchubaea
''Kutchubaea'' is a genus of plant in the family Rubiaceae
The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recogniz ...
''. The classification of the group remained difficult for a long time, which resulted in the placement of the genus ''Retiniphyllum'' in different tribes and subfamilies of Rubiaceae. Molecular studies place the genus in an isolated clade of the
Ixoroideae
Ixoroideae is a subfamily of flowering plants in the family Rubiaceae and contains about 4000 species in 27 tribes.
Tribes
* Airospermeae Kainul. & B.Bremer
* Alberteae Hook.f.
* Aleisanthieae Mouly, J.Florence & B.Bremer
* Augusteae Kainu ...
related to
paleotropical The Paleotropical Kingdom (Paleotropis) is a floristic kingdom comprising tropical areas of Africa, Asia and Oceania (excluding Australia and New Zealand), as proposed by Ronald Good and Armen Takhtajan. Part of its flora, inherited from the ancient ...
representatives.
The monophyly of the tribe Retiniphylleae has been confirmed and the tribe is placed as a clade within the subfamily Ixoroideae.
The genera ''
Botryarrhena
''Botryarrhena'' is a genus of flowering plants in the family Rubiaceae. It was described by Adolpho Ducke in 1932.Adolpho Ducke. 1932. Notizblatt des Botanischen Gartens und Museums zu Berlin-Dahlem 11: 476. It only holds two species, occurri ...
'' and ''
Scyphiphora'' were tentatively included in the tribe Retiniphylleae by Robbrecht (1988).
However, molecular data suggest that neither are related to ''Retiniphyllum''.
''
Botryarrhena
''Botryarrhena'' is a genus of flowering plants in the family Rubiaceae. It was described by Adolpho Ducke in 1932.Adolpho Ducke. 1932. Notizblatt des Botanischen Gartens und Museums zu Berlin-Dahlem 11: 476. It only holds two species, occurri ...
'' is resolved within the ''
Alibertia'' group, sister to ''
Stachyarrhena
''Stachyarrhena'' is a genus of flowering plants belonging to the family Rubiaceae
The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or ...
'' in a clade with the genera ''
Alibertia'', ''
Borojoa'' and ''
Kutchubaea
''Kutchubaea'' is a genus of plant in the family Rubiaceae
The Rubiaceae are a family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recogniz ...
''. The monotypic genus ''
Scyphiphora'' is sister to a clade that includes the tribe
Ixoreae
''Ixora'' is a genus of flowering plants in the family Rubiaceae. It is the only genus in the tribe Ixoreae. It consists of tropical evergreen trees and shrubs and holds around 544 species. Though native to the tropical and subtropical areas ...
and
Vanguerieae
Vanguerieae is a tribe of flowering plants in the family Rubiaceae and contains about 655 species in 30 genera. It is one of the most species-rich groups within the family and it is distributed across the Paleotropics.
Description
Several diff ...
.
Species
* ''
Retiniphyllum cataractae''
Ducke
* ''
Retiniphyllum chloranthum''
Ducke
* ''
Retiniphyllum concolor''
( Spruce ex 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 ...
) Johannes Müller Argoviensis, Müll.Arg.
* ''Retiniphyllum discolor''
( Spruce ex 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 ...
) Johannes Müller Argoviensis, Müll.Arg.
* ''Retiniphyllum fuchsioides''
Kurt Krause, K.Krause
* ''Retiniphyllum glabrum''
Julian Alfred Steyermark, Steyerm.
* ''Retiniphyllum guianense''
Julian Alfred Steyermark, Steyerm.
* ''Retiniphyllum kuhlmannii''
Paul Carpenter Standley, Standl.
* ''Retiniphyllum laxiflorum''
(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 ...
) Nicholas Edward Brown, N.E.Br.
* ''Retiniphyllum longiflorum''
Julian Alfred Steyermark, Steyerm.
* ''Retiniphyllum maguirei''
Paul Carpenter Standley, Standl.
* ''Retiniphyllum parvifolium''
Julian Alfred Steyermark, Steyerm.
* ''Retiniphyllum pauciflorum''
Carl Sigismund Kunth, Kunth ex Kurt Krause, K.Krause
* ''Retiniphyllum pilosum''
( Spruce ex 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 ...
) Johannes Müller Argoviensis, Müll.Arg.
* ''Retiniphyllum scabrum''
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 ...
* ''Retiniphyllum schomburgkii''
(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 ...
) Johannes Müller Argoviensis, Müll.Arg.
* ''Retiniphyllum secundiflorum''
Friedrich Wilhelm Heinrich Alexander von Humboldt, Humb. & Aimé Jacques Alexandre Bonpland, Bonpl.
* ''Retiniphyllum speciosum''
( Spruce ex 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 ...
) Johannes Müller Argoviensis, Müll.Arg.
* ''Retiniphyllum tepuiense''
Julian Alfred Steyermark, Steyerm.
* ''Retiniphyllum truncatum''
Johannes Müller Argoviensis, Müll.Arg.
References
External links
''Retiniphyllum'' in the World Checklist of Rubiaceae
{{Taxonbar, from=Q628706
Rubiaceae genera
Retiniphylleae
Taxa named by Aimé Bonpland
Taxa named by Alexander von Humboldt