Cyperus L. (Linnaeus 1753: 44)

Rasaminirina, Fitiavana & Larridon, Isabel, 2023, The genera of Cyperaceae of Madagascar, Plant Ecology and Evolution 156 (3), pp. 276-310 : 276

Cyperus L. (Linnaeus 1753: 44)

Kyllinga Rottb. ( Rottbøll 1773: 12), nom. cons.

Remirea Aubl. ( Aublet 1775: 44)

Mariscus Vahl ( Vahl 1805: 372), nom. cons.

Pycreus P.Beauv. ( Palisot de Beauvois 1807 publ. 1816: 48)

Lipocarpha R.Br. ( Brown 1818: 459)

Torulinium Desv. ex Ham. ( Hamilton 1825: 15)

Oxycaryum Nees ( Nees von Esenbeck 1842: 90)

Ascolepis Nees (Nees von Esenbeck 1855: 105)

Queenslandiella Domin ( Domin 1915: 415)

Courtoisina Soják ( Soják 1979 publ. 1980: 193)

Type species.

Cyperus esculentus L.

Description of the genus.

Small to large annuals, or tufted, rhizomatous, stoloniferous or bulbiferous perennials. Culms mostly scapose, triangular to subterete, rarely winged, compressed or septate. Leaves eligulate (more rarely ligulate), sometimes reduced to a sheath; sheaths sometimes semisucculent; blade linear or rarely oblong or pseudopetiolate. Primary bracts often large and leaf-like, not sheathing, lowermost bract rarely erect. Inflorescence of few to many spikelets, in clusters called spikes, terminal, rarely pseudolateral, anthelate to capitate, rarely spicate or reduced to a single spikelet; partial inflorescences spike-like with spicately or digitately-arranged spikelets, or densely capitate. Spikelets with few to many, 2-ranked (very rarely spirally arranged) glumes, spikelet bract and prophyll more or less glume-like, each glume subtending a floret. Glumes deciduous or persistent; rachilla internodes elongated. Floret bisexual, very rarely unisexual or even dioecious. Bristles absent, lacking a gynophore. Stamens 1-3. Style (2-)3-fid, more rarely (sub)entire; base mostly not distinct, not thickened, persistent or deciduous. Nutlets most often 3-sided, with the flat side pressed against the spikelet rachilla, often obovoid or ellipsoid, rarely dorsiventrally compressed, rarely stipitate, beaked or not, surface smooth or with various ornamentations, rarely thickened, corky.

Distribution and ecology.

Cyperus is a cosmopolitan genus who can be found everywhere. Cyperus occurs throughout Madagascar; ca 145 species are known including e.g. Cyperus pectinatus Vahl (Figs 22 , 23 ).

Figures

Figure 22. Cyperus pectinatus. A. Habit (x 2 / 3). B. Inflorescence (x 1.5). C. Spikelet (x 3). D. Glume (x 10). E. Flower (x 10). F. Nutlet (x 10). A from Peter 8794; B-D, F from Greenway & Kanuri 12298; E from Richards 24601. Drawn by Juliet Beentje, reproduced with permission from the artist, originally published in Hoenselaar et al. (2010).

Figure 23. Diversity in the genus Cyperus. A. Cyperus cf. cyperoides. B. Cyperus obtusiflorus. C. Cyperus assimilis. All photos taken in the Itremo Massif Protected Area by Fitiavana Rasaminirina.