Accepted name: Ornduffia reniformis
Stoloniferous aquatic herb with floating or emergent leaves, the stems to 1 m tall. Leaves with blades roundish, to about 8 cm long. Flower clusters terminal, open, to about 3 cm long. Flowers to about 4 cm wide, the sepals to about 1 cm long, the petals to about 2 cm long, yellow; spring to summer.
SA, NSW, Vic, Tas
Source: (2002). Menyanthaceae. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.