English: Hornworts; Hornwort family.
Botany: aquatics, submerged; ponds, marshes, quiet streams; tropical, temperate; worldwide; roots absent; flowers under water; seed dispersal under water; pollen grains without holes, unlike almost all other plants such as monocots and dicots; leaves whorled, serrulate; flowers unisexual, solitary, monocioecious.
DD:
Hydrogen series,
Iron series.
TaxonomyCeratophyllaceae has 1 genus, Ceratophyllum.