Spirodela
Herb floating at water surface, solitary or thalli connected to form groups of 2–5 (or more) plants. Roots (1–)2–18 per thallus. Thallus symmetric or asymmetric, broadly ovate to elliptic, oblong-elliptic to obovate or slightly reniform, flat to biconvex, green, ventral (lower) surface often with red or purple tinge; veins 3–16; dorsal scale present on young thalli, but not persistent in older plants; ventral scale often pigmented, covering the bases of the secondary roots or united with the root sheaths of the primary roots. Budding pouch with near-marginal slit on the ventral surface in the basal half of the thallus. Inflorescence of 1 female and 2 male flowers together in a membranous bract; anther bilocular.
4 species, in temperate and tropical regions; 2 species in Victoria.
Conn, B.J. (1994). Lemnaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 168–173. Inkata Press, Melbourne.
Spinning
