Description:

• Perennial aquatic herbs, rooting in mud or free-floating
• Roots many, long and feathery in floating plants
• Leaves dimorphous; the emergent ones with often swollen, long petioles, and obovate, orbicular, spathulate or lanceolate blades; submerged leaves alternate, linear, with petioles sheathing stems, shortly stipulate
• Flowers in well-developed spikes or these reduced to 1 or 2 flowers
• Perianth funnel-shaped, with a somewhat curved tube and 6 subequal spreading lobes, blue or mauve
• Stamens 3 + 3, upper included, lower exserted; anthers dorsifixed, oblong, opening by longitudinal slits
• Ovary 3-locular; ovules many; style filiform; stigma slightly dilated, entire or very shortly lobed
• Capsule spindle-shaped, covered with marcescent perianth
• Seeds many, small, ovoid, finely ribbed
• x = 8 (aneuploids, polyploidy)

Nomenclature:

• Eichhornia Kunth
  • Kunth: 3 (1842)
  • Podlech: 1 (1969)
  • Obermeyer: 63 (1985)
  • Cook: 193 (1990)

Distribution & Notes:

• Global: Species 7, tropical America and Africa
• Southern Africa: Species 1: Eichhornia natans (P.Beauv.) Solms, N Namibia and Botswana
  • *E. crassipes (Mart.) Solms (Water hyacinth), originally from South America, has become one of the world's worst pests of waterways; in South Africa it is a declared weed and prohibited as an ornamental plant