''Cotula'' is a genus 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 ...

in the

sunflower family Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger fam ...

.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. A 1903 paper in the '' American Journal of Psychology'' defined a "habit, from the standpoint of psychology, ...

, leaf division,

involucre In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also look ...

, receptacle and

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...

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 (biology), tribe of flowering plants in the subfamily Asteroideae, which is part of the family Asteraceae. They are cosmopolitan distribution, distributed worldwide, with concentrations in central Asia, the Mediterranean Ba ...

. This genus was first mentioned by

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 ...

, 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 genus, genera. It is the first work to consistently apply binomial nomenclature ...

''. 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 studie ...

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 package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

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

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, a few in

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

and

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 ...

+ 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. 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

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

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

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 ...

(''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 (; ), commonly referred to as The Falklands, 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 from Cape Dub ...

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

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 ...

, the

Subantarctic Islands The sub-Antarctic zone is a physiographic region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46° and 60° south of the Equator. The subantarctic region inc ...

(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: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

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 players try to roll their ball (called a bowl) closest to a smaller ball (known as a "jack" or sometimes a "kitty"). The bowls are shaped (biased), so that they follow a curve ...

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