Description :

• Aquatic, monoecious, probably annual herbs; juveniles submerged; adults partly submerged with emergent leaves
• Leaves radical, with submerged petioles and short to long, linear to linear-lanceolate exserted blades, geniculate at base
• Inflorescence simple, verticillate, exserted, with 5-15 whorls
• Flowers inconspicuous, small, whitish, upper verticils male, lower female, surrounded at base by 3 connate bracts
• Male flowers 4-8 in each whorl, bracteolate, on short pedicels; sepals ovate; petals small or 0; stamens 3; sterile carpels 2 or 3
• Female flowers 3 in each verticil, ebracteolate, sessile or shortly pedicelled; sepals ovate, persistent; petals 0-3, minute; staminodes 3; carpels 3-6, free; ovule basal; style short; stigma 3-lobed
• Achenes 3, ovoid, rostrate, with lateral air chambers, faintly to distinctly ridged

Nomenclature:

• Wiesneria Micheli
  • Micheli: 82 (1881) as Wisneria
  • Bentham & Hooker: 1007 (1881) as Wisneria
  • Wright: 213 (1902) as Wisneria
  • Cook et al.: 111 (1974) as Wisneria
  • Cook: 30 (1990)
  • Brummitt: 696 (1992)

Distribution & Notes:

• Global : Species 3, SW India, tropical and subtropical Africa, and Madagascar
• Southern Africa : Species 1: Wiesneria schweinfurthii Hook.f., N Botswana