Carex L. (Linnaeus 1753: 972)

Carex L. (Linnaeus 1753: 972)

Schoenoxiphium Nees ( Nees von Esenbeck 1832: 531)

Type species.

Carex hirta L.

Description of the genus.

Generally perennials, rarely annuals, caespitose or rhizomatous, sometimes forming a compact tussock. Culms central or lateral, mostly scapose, rarely with nodes, simple, smooth or scabrid. Leaves generally present, glabrous or rarely hairy, sheath often surrounding culm, ligule or sometimes contraligule present at the junction of the sheath and the blade. Primary bracts leaf-like or not, sheathing or not. Partial inflorescences spike-like, unisexual or bisexual, with few to many spirally arranged bracts (or glumes), either subtending a female spikelet or a male floret. Inflorescence terminal, rarely pseudolateral, paniculate, often partly or completely contracted, rarely corymbose or anthelate with few to numerous spikes, less frequently reduced to a single spike, cladoprophylls sometimes swollen at the base, utriculiform and subtending a female floret; inflorescence mostly bisexual, rarely unisexual or florets dioecious. Spikes male, female, or bisexual, and then mostly male florets apically, rarely basally, or intermingled; female spikelet reduced to the rachilla and a utriculiform, flower-bearing prophyll, completely enclosing the rachilla. Glumes 0 or 1. Floret unisexual; staminate flowers without scales; pistillate flowers with 1 scale with fused margins (perigynium) enclosing flower, open only at apex. Bristles absent. Stamens 1-3, filaments distinct, anthers linear. Style 2-3-fid, exserted, base not distinct, rarely thickened, persistent. Nutlets often obovoid, trigonous, or dorsiventrally compressed, sometimes remarkably malformed.

Distribution and ecology.

Carex is a cosmopolitan genus ( POWO 2022). It grows in humid forest, wet grassland, in freshwater wetlands, on sand or rocks, usually at higher elevation. Carex (Fig. 12B View Figure 12 ) occurs throughout Madagascar; 30 species are known.