genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
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 Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Zygophyllaceae
Zygophyllaceae is a family of flowering plants that contains the bean-caper and caltrop. The family includes around 285 species in 22 genera.
Plants in the family Zygophyllaceae may be trees, shrubs, or herbs. They are often found in dry habit ...
.
Description
Species of ''Tetraena'' are
shrub
A shrub (often also called a 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 or
herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of t ...
, the tallest being around . 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
petal
Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...
s and five
sepal
A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...
s, rarely four, and ten
stamen
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10
Morphology and terminology
A stamen typically consists of a stalk called the filame ...
s. The flower is usually tube-like in appearance with white to pale orange petals. The
ovary
The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. ...
has three to five chambers (
locule
A locule (plural locules) or loculus (plural loculi) (meaning "little place" in Latin) is a small cavity or compartment within an organ or part of an organism (animal, plant, or fungus).
In angiosperms (flowering plants), the term ''locule'' usu ...
s). The ripe fruit is variable in shape, splitting into parts before releasing the seeds.
Taxonomy
The genus ''Tetraena'' was erected by
Karl Maximovich
Carl Johann Maximovich (also Karl Ivanovich Maximovich, Russian: Карл Иванович Максимович; 23 November 1827 in Tula, Russia – 16 February 1891 in Saint Petersburg) was a Russian botanist. Maximovich spent most of his life ...
in 1889 for the species '' Tetraena mongolica''. Until 2003, this was the only species recognized in the genus.
Molecular phylogenetic
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...
studies suggested that the genus ''
Zygophyllum
''Zygophyllum'' is the type genus of the flowering plant family Zygophyllaceae. The generic name is derived from the Greek words ζυγόν (''zygon''), meaning "double", and φυλλον (''phyllon''), meaning "leaf". It refers to the leaves, ...
'' was not
monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...
, 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, though
IPNI
The International Plant Names Index (IPNI) describes itself as "a database of the names and associated basic bibliographical details of seed plants, ferns and lycophytes." Coverage of plant names is best at the rank of species and genus. It inclu ...
still treats it as a synonym of
Zygophyllum
''Zygophyllum'' is the type genus of the flowering plant family Zygophyllaceae. The generic name is derived from the Greek words ζυγόν (''zygon''), meaning "double", and φυλλον (''phyllon''), meaning "leaf". It refers to the leaves, ...
.
Species
,
Plants of the World Online
Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...
Tetraena cornuta
''Tetraena'' is a genus of flowering plants in the family Zygophyllaceae.
Description
Species of ''Tetraena'' are shrubby or herbaceous, the tallest being around . The leaves are opposite, or sometimes borne on short shoots and then appearing to ...
'' (Coss.) Beier & Thulin
*''
Tetraena cylindrifolia
''Tetraena'' is a genus of flowering plants in the family Zygophyllaceae.
Description
Species of ''Tetraena'' are shrubby or herbaceous, the tallest being around . The leaves are opposite, or sometimes borne on short shoots and then appearing to ...
Tetraena fontanesii
''Tetraena fontanesii'', synonym ''Zygophyllum fontanesii'', is a species of plant of the family Zygophyllaceae. It is found in Macaronesia and northwest Africa.
Description
This halophile and xerophile
A xerophile () is an extremophilic organi ...
Tetraena madecassa
''Tetraena'' is a genus of flowering plants in the family Zygophyllaceae.
Description
Species of ''Tetraena'' are shrubby or herbaceous, the tallest being around . The leaves are opposite, or sometimes borne on short shoots and then appearing to ...
Tetraena retrofracta
''Tetraena'' is a genus of flowering plants in the family Zygophyllaceae.
Description
Species of ''Tetraena'' are shrubby or herbaceous, the tallest being around . The leaves are opposite, or sometimes borne on short shoots and then appearing to ...
Canary Islands
The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...
in the west and
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...