Myriophyllum L.

Aquatic plants or growing on mud. Petals absent in female flowers Myriophyllum
At least submerged leaves whorled or opposite
At least submerged leaves in whorls of 3–8
Emerged leaves pinnately lobed, narrow-elliptic to ovate in outline, in whorls of 4–8
At least the upper emerged leaves not lobed to the midrib; the lobes not narrow-linear, 3–9 mm long. Bracteoles entire or denticulate. Mericarps rugose. Woronora Plateau and Blue Mts In water or on mud Myriophyllum verrucosum
Emerged leaves all with fine linear lobes to the midrib, narrow-elliptic in outline, up to 25 mm long; submerged leaves more finely dissected. Bracteoles linear, divided. Mericarps not produced in Aust. Coast and Cumberland Plain. Still water. Introd. from S. America. Possum Tail or Parrot’s Feather Myriophyllum aquaticum