The Cyperaceae are a family of
graminoid
In botany and ecology, graminoid refers to a herbaceous plant with a grass-like morphology, i.e. elongated culms with long, blade-like leaves. They are contrasted to forbs, herbaceous plants without grass-like features.
The plants most ofte ...
(grass-like),
monocotyledonous flowering plants known as sedges. The
family is large, with some 5,500 known species described in about 90
genera
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
,
the largest being the "true sedges" genus ''
Carex''
with over 2,000 species.
These species are widely distributed, with the centers of diversity for the group occurring in
tropic
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
al
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 ...
and tropical
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 souther ...
. While sedges may be found growing in almost all environments, many are associated with
wetlands
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
, or with poor soils.
Ecological communities
In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area at the same time, also known as a biocoenosis, biotic community, biological community, ecological community, ...
dominated by sedges are known as sedgelands or sedge meadows.
Some species superficially resemble the closely related
rushes and the more distantly related
grasses. Features distinguishing members of the sedge family from grasses or rushes are stems with triangular cross-sections (with occasional exceptions, a notable example being the
tule which has a round cross-section) and leaves that are spirally arranged in three ranks. In comparison, grasses have alternate leaves, forming two ranks.
Some well-known sedges include the water chestnut (''
Eleocharis dulcis
''Eleocharis dulcis'', the Chinese water chestnut or water chestnut, is a grass-like sedge native to Asia, tropical Africa, and Oceania. It is grown in many countries for its edible corms.
The water chestnut is not a nut, but an aquatic ve ...
'') and the papyrus sedge (''
Cyperus papyrus''), from which the writing material
papyrus was made. This family also includes cotton-grass (''
Eriophorum
''Eriophorum'' (cottongrass, cotton-grass or cottonsedge) is a genus of flowering plants in the family Cyperaceae, the sedge family. They are found throughout the arctic, subarctic, and temperate portions of the Northern Hemisphere in acid bog ...
''), spike-rush (''
Eleocharis
''Eleocharis'' is a virtually cosmopolitan genus of 250 or more species of flowering plants in the sedge family, Cyperaceae. The name is derived from the Greek words ἕλειος (''heleios''), meaning "marsh dweller," and χάρις (''charis'' ...
''), sawgrass (''
Cladium''), nutsedge or nutgrass (''
Cyperus rotundus'', a common lawn weed), and white star sedge (''
Rhynchospora colorata
''Rhynchospora colorata'', also known as starrush whitetop, white star sedge and white-topped sedge, is a perennial sedge with white bracts, giving it the appearance of white petals with long, green points. It is native to southeastern North Amer ...
'').
Genera
, 88 genera are accepted in
Kew's
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 ...
:
[
]
References
External links
Cyperaceae
at th
''Angiosperm Phylogeny Website''
{{Authority control
Poales families