Rotala L.

6 species in Aust. (2 endemic, 3 native, 1 naturalized); Qld, NSW, NT, WA

*Rotala rotundifolia (Buch.-Ham. ex Roxb.) Koehne

Annual or perennial herb; stems creeping, erect or floating. Leaves opposite, decussate, sessile to subsessile, orbicular, 12 mm diam., lower surface pale green to reddish. Flowers numerous, sessile in terminal spikes. Petals 4, mauve to pink. Stamens 4, inserted at base of hypanthium. Ovary 2–4 locular. Capsule 2–4 mm long with 4 valves. Seed numerous. Grows in damp or submerged areas. Introd. from S. Asia. Fl. spring