Red Azolla, Pacific Azolla, Red Duckweed
Floating fern, leaves red (or green in shaded areas). Leaves alternating along the stem, mostly less than 0.2cm long, flat, deeply 2-lobed, the smaller lobe submerged. The whole plant 1-3cm long and broad. Family Azollaceae in SA.
Description and photo (as Azolla filiculoides var. rubra) in G.M. Cunningham, WE Mulham, PL Milthorpe and J H Leigh (1981 and later printings) Plants of Western New South Wa les page 34