A water nymph of Roman mythology.

Aquatic perennial herbs. Leaves submerged, whorled in groups of 3-8, spathe with a cleft. Flowers floating or held above the surface, conspicuous, the sexes on separate plants, perianth in 2 whorls, each of 3 segments, the outer sepal-like, the inner large and petal-like. Male flowers 2-4 per spathe, soon detached and free-floating, stamens 9. Female flower solitary. Fruit a capsule with 1-5 seeds.

Aquarium plants. The genus sometimes included in Elodea.

2 species from subtropical S America. 1 species naturalised in Australia.

Cuttings.

Leaves 4-5 together in a whorl; flowers held above the water and with inner segments larger than the outer ones cf. Elodea.

St John (1961).

Source: Spencer, R. (2005). Hydrocharitaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 5. Flowering plants. Monocotyledons. The identification of garden and cultivated plants. University of New South Wales Press.