Tetraena
Tetraena fontanesii
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Zygophyllales
Family:	Zygophyllaceae
Subfamily:	Zygophylloideae
Genus:	Tetraena Maxim.[1]

Tetraena is a genus of flowering plants in the family Zygophyllaceae.^[1]

Description

Species of Tetraena are shrubby or herbaceous, the tallest being around 1.5 m (4.9 ft). The leaves are opposite, or sometimes borne on short shoots and then appearing to be alternate. They may or may not have stalks (petioles). The flower usually has five petals and five sepals, rarely four, and ten stamens. The flower is usually tube-like in appearance with white to pale orange petals. The ovary has three to five chambers (locules). The ripe fruit is variable in shape, splitting into parts before releasing the seeds.^[2]

Taxonomy

The genus Tetraena was erected by Karl Maximovich in 1889 for the species Tetraena mongolica. Until 2003, this was the only species recognized in the genus. Molecular phylogenetic studies suggested that the genus Zygophyllum was not monophyletic, since Tetraena and some other genera were nested within it. To create monophyletic genera, Björn-Axel Beier and Mats Thulin transferred about 40 species of Zygophyllum to Tetraena, creating a much expanded genus,^[2] though IPNI still treats it as a synonym of Zygophyllum.^[1]

Distribution

Tetraena is native from the Canary Islands in the west and South Africa in the south to China in the east.^[2]

References