Magnoliophyta
Ovules (and seeds) enclosed within carpels (fruits); the carpels bearing stigmas upon which the pollen lodges. Pollen produced in the anthers of stamens. Carpels and stamens usually surrounded by a perianth; the whole constituting a flower which may be uni- or bi-sexual (= angiosperms) Magnoliophyta
Flowers usually 3-merous. Leaf venation usually parallel. Embryo with 1 cotyledon Plants usually herbaceous rarely woody and then ± unbranched) Liliopsida
Ovary inferior
Partially or wholly submerged herbs, sometimes marine Hydrocharitaceae
Leaves prominently sharply toothed so as to appear almost pinnatifid, 12–15 mm long, c. 5 mm wide, dilated at the base into a short sheath without auricles. Carpels mostly with 3 stigmas. Dioecious annual. Coast. Lagoons, in fresh to slightly brackish water. Fl. spring–autumn Najas marinalatior
Leaves inconspicuously toothed, with auriculate sheaths, up to 5 cm long, 1–3 mm wide. Carpels with 2 or 3 stigmas