Species commonly cultivated
Ondinea purpurea Hartog (Australia)
Annual. Stem a corm-like rhizome. Leaves submersed or floating, in a basal rosette arising from buried rhizome; petiole smooth, highly elongate; leaf blade deeply sagittate (when submersed) to oblong-elliptic with deep sinus (when floating), venation palmate; margin entire but deeply undulate in submersed form. Inflorescence a solitary flower borne at or above water surface on a long pedicel. Sepals 4, elongate, purple-red; petals present or absent; stamens numerous. Dispersal by small seeds.
ephemeral streams, ponds, and rivers
Ondinea is represented by a single species, although several geographical varieties exist. A rare and potentially endangered plant, it is restricted to northwestern Australia and could be threatened by over collection from the wild. Ondinea is difficult to propagate over the long term in aquaria or ponds. A perennial plant, Ondinea is often found in ephemeral pools and rivers that are dry for a significant portion of the year. The root stock survives the dry season in drying mud. Germination of seeds is apparently sensitive to water chemistry. A common incorrect spelling is 'Ondinia'.