Western Milfoil, Western Watermilfoil, Western Water Milfoil, Western Water-milfoil: Myriophyllum hippuroides
Andean Watermilfoil, Andean Water-milfoil, Waterwort Milfoil, Waterwort Water Milfoil: Myriophyllum quitense (Synonym: Myriophyllum elatinoides)
American Milfoil, Common Water Milfoil, Northern Milfoil, Siberian Water Milfoil: Myriophyllum sibiricum (Synonym: Myriophyllum exalbescens, Myriophyllum spicatum var. exalbescens)
Eurasian Watermilfoil, Eurasian Water Milfoil, Eurasian Water-milfoil, Spike Water-milfoil, Spiked Water Milfoil: Myriophyllum spicatum (Synonym: Myriophyllum spicatum var. spicatum)