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