''Tetragonia'' is a genus of 51 species of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the family

Aizoaceae The Aizoaceae (), or fig-marigold family, is a large family of dicotyledonous flowering plants containing 135 genera and about 1,800 species. Several genera are commonly known as 'ice plants' or 'carpet weeds'. The Aizoaceae are also referred to a ...

, native to temperate and subtropical regions mostly of the Southern Hemisphere, in

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, southern and eastern

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

, and western

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

, and eastern Asia.

Description

Plants of the genus ''Tetragonia'' are

herbs Herbs are a widely distributed and widespread group of plants, excluding vegetables, with savory or aromatic properties that are used for flavoring and garnish (food), garnishing food, for medicinal purposes, or for fragrances. Culinary use typi ...

or small

shrubs A shrub or 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 their multiple ...

Leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are alternate and

succulent In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

, with flowers typically yellow and small in size. Flowers can be axillary, solitary or fasciculate, greenish or yellowish in colour and mostly bisexual.

Fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

are initially succulent but become dry and woody with age. The genus name comes from ''"tetragonus"'', meaning ''"four-angled"'' and referring to the shape of the plants' fruits. Sphaeraphides occur in at least the leaves and stalks of at least some species.

Distribution

About forty species of ''Tetragonia'' are found in southern Africa, from Angola to South Africa. They also occur in Australia, eastern Africa (Kenya and Ethiopia), western south America (Peru and Chile), and Asia (Japan, Korea, Taiwan, southern China, Myanmar, and Vietnam).

Classification

The genus was first formally described by the

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

in 1753 in the work ''

Species Plantarum ' (Latin for "The Species of Plants") is a book by Carl Linnaeus, originally published in 1753, which lists every species of plant known at the time, classified into genus, genera. It is the first work to consistently apply binomial nomenclature ...

''. Synonyms for the genus include ''Tetragonocarpos'' Mill., ''Demidovia'' Pall., and ''Tetragonella'' Miq.

Human use and cultivation

The best known species of ''Tetragonia'' is the leafy

vegetable Vegetables are edible parts of plants that are consumed by humans or other animals as food. This original meaning is still commonly used, and is applied to plants collectively to refer to all edible plant matter, including edible flower, flo ...

food Food is any substance consumed by an organism for Nutrient, nutritional support. Food is usually of plant, animal, or Fungus, fungal origin and contains essential nutrients such as carbohydrates, fats, protein (nutrient), proteins, vitamins, ...

crop A crop is a plant that can be grown and harvested extensively for profit or subsistence. In other words, a crop is a plant or plant product that is grown for a specific purpose such as food, Fiber, fibre, or fuel. When plants of the same spe ...

, ''

Tetragonia tetragonoides ''Tetragonia tetragonioides'', commonly called New Zealand spinach, warrigal greens and other local names, is a flowering plant in the fig-marigold family (Aizoaceae). It is often cultivated as a leafy vegetable. It is a widespread species, nat ...

'' ("New Zealand spinach"). New Zealand spinach is widely cultivated as a summer leafy vegetable. Some of the other species are also eaten locally, such as ''

Tetragonia decumbens ''Tetragonia decumbens'' (dune spinach or sea spinach) is a coastal shrub, native to southern Africa. Description It grows as a trailing undershrub with thick, pale, furry stems, and thick, oval, saddle-shaped leaves 10-60 millimetres long and ...

'' ("Dune spinach") which is a local delicacy in its native

southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

Species

51 species are accepted. *''

Tetragonia acanthocarpa ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia angustifolia ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America, ...

'' *''

Tetragonia arbuscula ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia caesia ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia calycina ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia chenopodioides ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia copiapina ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *''

Tetragonia coronata ''Tetragonia coronata'' is a member of the genus ''Tetragonia'' and is endemic to Australia. The annual herb has a decumbent habit. It blooms in July producing yellow flowers. Often found among calcrete outcrops it has a scattered distribution ...

'' *'' Tetragonia cristata'' *'' Tetragonia crystallina'' *''

'' *'' Tetragonia diptera'' *'' Tetragonia distorta'' *'' Tetragonia echinata'' *'' Tetragonia erecta'' *'' Tetragonia eremaea'' *''

Tetragonia espinosae ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *'' Tetragonia fruticosa'' *'' Tetragonia galenioides'' *'' Tetragonia glauca'' *'' Tetragonia halimoides'' *'' Tetragonia haworthii'' *''

Tetragonia herbacea ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America, ...

'' *'' Tetragonia hirsuta'' *''

Tetragonia implexicoma ''Tetragonia implexicoma'', commonly known as bower spinach, is a species of plant in the Aizoaceae, or ice-plant family. A similar species is ''Tetragonia tetragonioides'', however this species has larger leaves and a shorter flowering time. Di ...

'' *'' Tetragonia lasiantha'' *'' Tetragonia macrocarpa'' *'' Tetragonia macroptera'' *''

Tetragonia maritima ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *'' Tetragonia microcarpa'' *''

Tetragonia microptera ''Tetragonia'' is a genus of 51 species of flowering plants in the family Aizoaceae, native to temperate and subtropical regions mostly of the Southern Hemisphere, in New Zealand, Australia, southern and eastern Africa, and western South America ...

'' *'' Tetragonia moorei'' *'' Tetragonia namaquensis'' *'' Tetragonia nigrescens'' *'' Tetragonia ovata'' *'' Tetragonia pedunculata'' *'' Tetragonia pillansii'' *'' Tetragonia portulacoides'' *'' Tetragonia rangeana'' *'' Tetragonia reduplicata'' *'' Tetragonia robusta'' *'' Tetragonia rosea'' *'' Tetragonia saligna'' *'' Tetragonia sarcophylla'' *'' Tetragonia schenckii'' *'' Tetragonia sphaerocarpa'' *'' Tetragonia spicata'' *''

'' *'' Tetragonia verrucosa'' *'' Tetragonia vestita'' *'' Tetragonia virgata''

Gallery

File:Tetragonia decumbens03.jpg, ''

'' File:Tetragonia echinata0.jpg, '' Tetragonia echinata'' File:Tetragonia implexicoma habit.jpg, ''

'' File:Tetragonia ovata, Aizoaceae (8464390152).jpg, '' Tetragonia ovata''

References

Bibliography

* {{Taxonbar, from=Q133932 Aizoaceae genera Taxa named by Carl Linnaeus