Description:

• Aquatic, rhizomatous, perennial herbs rooted in bottom mud
• Leaves spirally arranged on rhizome, usually round or oval, cordate, floating, rarely emergent or submerged, petiolate (petioles often very long), usually ± peltate, palmately veined, entire to dentate; stipules present
• Flowers regular, bisexual, solitary, usually large, showy, often scented, mostly long-pedunculate, floating, emergent or rarely submerged
• Sepals 4 (but ± sepaloid petals can be present), ± green
• Petals 5-many, arising from successively higher levels on ovary, outermost usually equalling or shorter than sepals, innermost shorter and narrower, grading into stamens
• Stamens many, spirally arranged, outer with broad petaloid filaments; filaments arising from top of ovary, often extending as a sterile appendage beyond anther thecae; anthers obtuse, opening by longitudinal slits, introrse
• Ovary sunk in receptacle, syncarpous, many-locular; ovules many per locule, pendulous from walls or apex; stigmatic surfaces radiating from central apical boss of ovary, with marginal stylar processes
• Fruit a large berry, fleshy or spongy, ripening under water, eventually splitting
• Seeds many, small, floating due to air-containing, sack-like, pulpy aril; sinking to bottom and germinating when aril decays; endosperm scanty, perisperm copious
• x = 7 (9) (high polyploidy)

Nomenclature:

• Nymphaea L.
  • Linnaeus: 510 (1753)
  • Harvey: 14 (1860)
  • Mendonça: 175 (1960)
  • Verdcourt: 1 (1989)
  • Cook: 135 (1990)
  • Schneider & Williamson: 491 (1993)
  • Thulin: 23 (1993)

Distribution & Notes:

• Global: Species ± 40 plus several hybrids, cosmopolitan in tropical and temperate climates
• Southern Africa: Species 2, widespread