Oxygonum
Oxygonum | |
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Illustration of from Hooker's Icones Plantarum, volume 14 | |
Scientific classification ![]() | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Caryophyllales |
Family: | Polygonaceae |
Subfamily: | Polygonoideae |
Genus: | Oxygonum Burch. ex Campd.[1] |
Species | |
See text. |
Oxygonum is a genus of plants in the family Polygonaceae with about 30 species. It is native to eastern parts of Africa and to the Arabian Peninsula.[1]
Description[]
Species of Oxygonum are annual or perennial herbaceous plants, more rarely shrubs or shrubby. Their leaves are variable between and within species. The inflorescences are long narrow racemes with bundles (fascicles) of flowers, usually one to five, but sometimes up to 15. The flowers are polygamous (i.e. there are male, female and bisexual flowers on the same plant). There are usually five tepals, arranged spirally, fused at the base to form a tube, longer in female flowers than in male ones. The eight stamens are joined at the base, with patches of nectar-bearing tissue at the base of the inner whorl. The fruit is in the form of an achene, usually three-angled, often with rows of spinelike structures.[2]
Taxonomy[]
The genus Oxygonum was first published in 1819 by , who attributed the name to William John Burchell.[1][3] Oxygonum is placed in the tribe Oxygoneae of the subfamily Polygonoideae; it is the only genus in the tribe. A 2015 molecular phylogenetic study suggested that it was the sister of all the remaining tribes.[2]
Polygonoideae |
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Species[]
As of March 2019, Plants of the World Online accepted the following species:[1]
- Welw.
- Burch.
- Germish.
- S.Ortiz & Paiva
- (Meisn.) Martelli
- R.A.Graham
- (Dammer) J.B.Gillett
- R.A.Graham
- Kuntze
- Meisn.
- R.A.Graham
- Dammer ex Milne-Redh.
- R.A.Graham
- S.Ortiz
- Peter
- Mildbr.
- R.A.Graham
- De Wild.
- R.A.Graham
- R.A.Graham
- R.A.Graham
- Dammer ex Peter
- Robyns & E.Petit
- Robyns
- Milne-Redh.
- Osborne & Vollesen
- De Wild.
- Germish.
- R.A.Graham
- Dammer
- Mildbr.
- (Hochst. & Steud. ex Meisn.) Dammer
- Dammer
- R.A.Graham
- Milne-Redh.
- S.Ortiz
- Staner
References[]
- ^ Jump up to: a b c d "Oxygonum Burch.", Plants of the World Online, Royal Botanic Gardens, Kew, retrieved 2019-03-08
- ^ Jump up to: a b Schuster, Tanja M.; Reveal, James L.; Bayly, Michael J. & Kron, Kathleen A. (2015), "An updated molecular phylogeny of Polygonoideae (Polygonaceae): Relationships of Oxygonum, Pteroxygonum, and Rumex, and a new circumscription of Koenigia", Taxon, 64 (6): 1188–1208, doi:10.12705/646.5
- ^ Campderá, Francisco (1819), "Genarum Polygonaearum Clavis Dichotomica", Monographie des Rumex, Paris: Treuttel & Würtz, retrieved 2019-03-08
- Polygonaceae genera
- Polygonoideae