small green aphids on spotless watermeal (wolffia arrhiza), duckweed (lemna turionifera

aphids alga algae aquatic plant plants araceae bazaar common duckweeds duckweed floating flora fresh green background growth invasive species lake leaf leaves lemna turionifera lemnaceae natural nature nile cabbage petal pistia stratiotes pistieae pond pontederia rootless seaweed shellflower spotless watermeal surface swamp tiny top view water lettuce wolffia