Anthurium belongs to the family Araceae.
Members of the Araceae are especially abundant as shade plants in tropical rain forests. Family members native to this region include Jack-in-the-pulpit and skunk cabbage. The reproductive structure of Araceae is a spadix (a fleshy spike with very small flowers) surrounded by a bract (a modified leaf). In the tropics, some species of Araceae are used as a source of starch; however other species are poisonous due to crystals of calcium oxalate.
Sagittaria is in the family Alismataceae.
Plants of the family Alismataceae often grow in aquatic habitats. They have multiple pistils (developing into fruit) and multiple stamens in each flower. The flowers are pollinated by nectar-gathering insects and fruits are dispersed by waterfowl or by floating in the water. Few plants in this family have economic importance, though some are grown as ornamentals in water gardens.