Cyperus

Cyperus papyrus

The genus Cyperus, established by Linnaeus in 1753, belonging to the Cyperaceae family. It is made up of some 700 accepted species, of the more than 2,500 described, distributed throughout all continents, both in tropical and temperate regions. They are annual or perennial plants, in many cases pioneers, they can come to dominate or monopolize certain environments. Species vary greatly in size, from as small as 5 cm to 5 m tall. The stems can be circular, with transversal cuts in some, triangular in others, and normally with a fairly long internode, which makes basal and apical leaves visible.^{[citation needed] The flowers are greenish and are born clustered between the apical leaves. The seed is a small grain that is disseminated by the wind for pollination. In Venezuela there are about 57 species of this genus.}

Cyperus papyrus, native to Africa, was of primary historical importance in the supply of papyrus.
Other species such as C. rotundus are important invasive herbs. Cyperus esculentus, the tiger nut, native to India, has edible tubers for which it is cultivated; some other species are also consumed, although to a lesser extent. Some of the species have a certain commercial value and others are cultivated as ornamentals. Interest is increasing in the larger, fast-growing species as biomass crops for paper and fuel production. In addition C. articulatus, C. sphacelatus, C. luzulae and C. involucratus are useful to man as medicinal or ornamental.

Description

They are herbaceous plants in tufts or rhizomatous, perennial or annual; culms triquetrous or rounded; hermaphrodite or very rarely dioecious plants (C. canus). Leaves only basal (bladeless in several species). Inflorescence bracts without lamina, grouped in the upper part of the culm, each holding a ray (peduncle), spikelets cylindrical or compressed, arising spiked or fingered at the ends of the rays or their branches, flowers in the axils of scales couplets, whose bases are frequently decurrent on the rachilla in the form of hyaline wings; perianth absent; stamens (1–) 3; styles 2- or 3-branched. Triquetro or lenticular fruit.

Taxonomy

The genus was described by Charles Linnaeus and published in Species Plantarum 1: 44. 1753. The type species is: Cyperus esculentus L.

Etymology

Cyperus: generic name that comes from the Greek name kypeiros, given to these plants.

Selected species