Myriophyllum
English: Watermilfoil
Species: 69 species.
Region: cosmopolitan; Australia with 43 recognized species.
Name: from Greek, "myrio" meaning "ten thousand", and "phyllum" meaning "leaf".
Botany: submersed, freshwater, aquatic plants; elongate stems with air canals; leaves whorled, finely pinnately divided, stiffer and smaller above the water; heterophyllous; monoecious or dioecious; flowers small, 4 or 2-parted, usually axillary, female flowers lack petals; fruit a schizocarp that splits into four to 2 nutlets at maturity.
Use: fruits and leaves can be an important food source for waterfowl.