3160.000 Hydrostachys Thouars

Submerged fern-like, annual or rarely perennial herbs found on rocks in fast-flowing fresh water; rhizome forms a compact circle of roots firmly attached to the rocks. Leaves basal 2-3 pinnatifid, petiolate, dilated at the base, petiole and rhachis covered in warty protuberances. Inflorescence emergent, densely spicate. Flowers small, sessile, solitary in axils of spirally arranged bracts. Fruit a 2-valved capsule enclosed in a persistent bract. Seeds small, light.

Worldwide: 22 species in Africa south of the equator and Madagascar.

Zambia: 1 taxon.