''Cotula'' is a genus 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 ...

in the sunflower family.Tropicos, ''Cotula'' L.
/ref> It includes plants known generally as water buttons or buttonweeds. The species within this genus can vary extensively in their

habit A habit (or wont as a humorous and formal term) is a routine of behavior that is repeated regularly and tends to occur subconsciously.

, leaf division,

involucre In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

, receptacle and

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

s. This makes it difficult to define them by comparing their

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

. The genus can only be defined by looking at the corollas of their flowers. Most are disciform (lacking ray florets). These corollas may be tubular, reduced or even absent. Another characteristic is their solitary heads growing on a peduncle.

Taxonomy

''Cotula'' is the largest genus found in the Southern Hemisphere of the tribe

Anthemideae Anthemideae is a tribe of flowering plants in the family, Asteraceae, and the subfamily Asteroideae. They are distributed worldwide with concentrations in central Asia, the Mediterranean Basin, and southern Africa.Oberprieler, C., et al. (2007) A ...

. This genus was first mentioned by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

, who described four species in his first edition (1753) of ''

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 genera. It is the first work to consistently apply binomial names and was the ...

''. In 1867 the genus was subdivided by

George Bentham George Bentham (22 September 1800 – 10 September 1884) was an English botanist, described by the weed botanist Duane Isely as "the premier systematic botanist of the nineteenth century". Born into a distinguished family, he initially studi ...

Bentham, G., 1867: "Flora Australiensis", Vol. 3. Reeve, London. into three sections. Since his account, only a few changes have been made but the number of species has remained more or less stable. The sections possess different basic

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

numbers : * section ''Cotula'' : largest section with about 40 species; mostly in

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 ...

, a few in

North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...

and

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

+ the cosmopolitan species ''C. coronopifolia'' and the widespread species ''C. turbinata;'' this section also includes the former genera ''Cenia'' and ''Otochlamys''; basic chromosome numbers x = 8 and x = 10. * section ''Strongylosperma'' (Less.) Benth.: a total of eight species, found in warmer parts of

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

and

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

(often lumped as ''C. anthemoides''),

Central Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as ...

and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

(''C. mexicana'') and

(five species, including ''C. australis''); basic chromosome number : x = 18 * section ''Leptinella'' (Cass.) Hook f. : the remaining thirty species, found in

and the

Falkland Islands The Falkland Islands (; es, Islas Malvinas, link=no ) is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and about from Cape Dubouzet ...

(the type species ''C. scariosa''),

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

, the Subantarctic Islands (together 24) and five species from

and

.; the species in this section have a distinctive characteristic not found in the other sections : inflated pistillate corollas; basic chromosome number : x = 13. See also ''

Leptinella ''Leptinella'' is a genus of alpine flowering plant in the family Asteraceae, comprising 33 species, distributed in New Guinea, Australia, New Zealand, South Africa, and South America. Many of the species are endemic to New Zealand. For over 10 ...

''. David G. Lloyd has proposed that the five species from

and

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

are distinctive enough from the other species from the section ''Leptinella'' to be brought under a new section with the proposed name ''Oligoleima'' (type species ''C. longipes''). ; Species

Uses

''Cotula'' is used in

as ground cover for bowling greens, playing fields on which the ball-game of

bowls Bowls, also known as lawn bowls or lawn bowling, is a sport in which the objective is to roll biased balls so that they stop close to a smaller ball called a "jack" or "kitty". It is played on a bowling green, which may be flat (for "flat-gre ...

is played

Footnotes

References

External links

* * {{Taxonbar, from=Q1807600 Asteraceae genera Taxonomy articles created by Polbot Taxa named by Carl Linnaeus

Taxonomy

Uses

Footnotes

References

Further reading

External links