Retiniphylleae
Encyclopedia
Retiniphylleae is a tribe
of flowering plant
s in the Rubiaceae
family
. It only holds the genus Retiniphyllum that contains 20 species
. The representatives of the tribe are shrubs or small trees that grow in white sand soils in tropical South America. They are mainly distributed in the Guayana Region (Venezuela
) but also occur in the Amazon Basin, the eastern Andes and central and eastern Brasil.
established the tribe Retiniphylleae in 1873 and included the genera Retiniphyllum and Kutchubaea. 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 related to paleotropical 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
and Scyphiphora were tentatively included in the tribe Retiniphylleae by Robbrecht (1988). However, molecular data suggest that neither are related to Retiniphyllum. Botryarrhena
is resolved within the Alibertia
group, sister to Stachyarrhena in a clade with the genera Alibertia
, Borojoa
and Kutchubaea. The monotypic genus Scyphiphora is sister to a clade that includes the tribe Ixoreae and Vanguerieae
.
Tribe (biology)
In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s in the Rubiaceae
Rubiaceae
The Rubiaceae is a family of flowering plants, variously called the coffee family, madder family, or bedstraw family. The group contains many commonly known plants, including the economically important coffee , quinine , and gambier , and the horticulturally valuable madder , west indian jasmine ,...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
. It only holds the genus Retiniphyllum that contains 20 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
. The representatives of the tribe 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
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
) but also occur in the Amazon Basin, the eastern Andes and central and eastern Brasil.
Description
The species in the tribe exhibit a character that is not common in the Rubiaceae family, 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 in the earliest systems of classification due to the misinterpretation of the bi-ovulated locules. William Jackson HookerWilliam Jackson Hooker
Sir William Jackson Hooker, FRS was an English systematic botanist and organiser. He held the post of Regius Professor of Botany at Glasgow University, and was the first Director of the Royal Botanic Gardens, Kew. He enjoyed the friendship and support of Sir Joseph Banks for his exploring,...
established the tribe Retiniphylleae in 1873 and included the genera Retiniphyllum and Kutchubaea. 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 related to paleotropical 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
Botryarrhena is a genus of flowering plants in the Rubiaceae family. It was descripted by Adolpho Ducke in 1932. It only holds two species that occur in Brazil, Colombia, Peru and Venezuela.-Species:* Botryarrhena pendula Ducke...
and Scyphiphora were tentatively included in the tribe Retiniphylleae by Robbrecht (1988). However, molecular data suggest that neither are related to Retiniphyllum. Botryarrhena
Botryarrhena
Botryarrhena is a genus of flowering plants in the Rubiaceae family. It was descripted by Adolpho Ducke in 1932. It only holds two species that occur in Brazil, Colombia, Peru and Venezuela.-Species:* Botryarrhena pendula Ducke...
is resolved within the Alibertia
Alibertia (plant genus)
Alibertia is a genus of flowering plants in the Rubiaceae family. It is found in tropical America.-Species:* Alibertia bertierifolia K.Schum.* Alibertia curviflora K.Schum.* Alibertia duckei Standl.* Alibertia edulis A.Rich...
group, sister to Stachyarrhena in a clade with the genera Alibertia
Alibertia (plant genus)
Alibertia is a genus of flowering plants in the Rubiaceae family. It is found in tropical America.-Species:* Alibertia bertierifolia K.Schum.* Alibertia curviflora K.Schum.* Alibertia duckei Standl.* Alibertia edulis A.Rich...
, Borojoa
Borojoa
Borojoa is a genus of flowering plants in the Rubiaceae family. It was described by José Cuatrecasas in 1949 and the name is derived from the Emberá word Borojó meaning: boro = head, ne-jo = fruit - head-shaped fruit, or round, globulous fruit. The genus is found in Central and South Tropical...
and Kutchubaea. The monotypic genus Scyphiphora is sister to a clade that includes the tribe Ixoreae and Vanguerieae
Vanguerieae
Vanguerieae is a tribe of flowering plants in the Rubiaceae family and contains about 600 species in 25 genera. The tribe is a common and important constituent of many different kinds of habitats...
.
Species
Retiniphylleae is monogeneric and currently only contains the genus Retiniphyllum. It has 20 species and the type species is Retiniphyllum secundiflorum.- Retiniphyllum cataractaeRetiniphyllum cataractaeRetiniphyllum cataractae is a species of flowering plant in the Rubiaceae family. It is endemic to the Amazonas. It was described for the first time by Adolpho Ducke in 1938....
Ducke - Retiniphyllum chloranthumRetiniphyllum chloranthumRetiniphyllum chloranthum is a species of flowering plant in the Rubiaceae family. It occurs from Colombia to Guyana and northern Brazil. It was described by Adolpho Ducke in 1943....
Ducke - Retiniphyllum concolorRetiniphyllum concolorRetiniphyllum concolor is a species of flowering plant in the Rubiaceae family. It occurs from Colombia to Guyana and northern Brazil....
(Spruce ex Benth.) Müll.Arg. - Retiniphyllum discolor (Spruce ex Benth.) Müll.Arg.
- Retiniphyllum fuchsioides K.Krause
- Retiniphyllum glabrum Steyerm.
- Retiniphyllum guianense Steyerm.
- Retiniphyllum kuhlmannii Standl.
- Retiniphyllum laxiflorum (Benth.) N.E.Br.
- Retiniphyllum longiflorum Steyerm.
- Retiniphyllum maguirei Standl.
- Retiniphyllum parvifolium Steyerm.
- Retiniphyllum pauciflorum Kunth ex K.Krause
- Retiniphyllum pilosum (Spruce ex Benth.) Müll.Arg.
- Retiniphyllum scabrum Benth.
- Retiniphyllum schomburgkii (Benth.) Müll.Arg.
- Retiniphyllum secundiflorum Humb. & Bonpl.
- Retiniphyllum speciosum (Spruce ex Benth.) Müll.Arg.
- Retiniphyllum tepuiense Steyerm.
- Retiniphyllum truncatum Müll.Arg.