Vallisneria
5 species native Aust.; all states and territories
Vallisneria gigantea
Submerged, fresh water, stoloniferous, dioecious herb. Leaves basal, tufted, linear, long and ribbon-like, 1–2 cm wide; margin obscurely dentate; nerves up to 9. Male flowers minute, numerous, enclosed in an ovoid spathe, detaching and floating to the surface; petals absent; stamens 2–3. Female flowers solitary, sessile in a tubular spathe on a long peduncle which is spirally coiled unwinding to allow the flower to reach the surface for pollination; sepals 3; petals obsolete. Widespread in fresh water. Fl. summer. Eel Grass