The family also contains the well-known Venus flytrap (Dionaea muscipula) and the more obscure waterwheel plant (Aldrovanda vesiculosa), both of which are the only living species of their respective genera.

Their leaves are alternate and adaxially circinate, with at least one leaf surface containing hairs with mucilage-producing glands at the tip.

Like carnivorous plants of other families, the Droseraceae are able to supplement their nutrient intake, especially that of nitrogen, by capturing and digesting small animals such as insects.

Drosera is one of the largest genera of carnivorous plants, and individual species vary extensively in their specific morphology.

Common to all members of Drosera are highly modified leaves lined with tentacle-like glandular trichomes.

[7] Dionaea muscipula, better known as the Venus flytrap, is a globally famous carnivorous plant and according to Charles Darwin, "one of the most wonderful in the world.

The Principia Botanica, published in 1787, states "Sun-dew (Drosera) derives its name from small drops of a liquor-like dew, hanging on its fringed leaves, and continuing in the hottest part of the day, exposed to the sun.

[11]  Although these genera had significant differences in leaf and flower morphologies, they were grouped together on the basis of insect traps that appeared to be homologous.

This important morphological distinction led researchers to question the validity of this taxon's placement in Droseraceae.

Other significant trait differences in Drosophyllum include pollen structure, trichome anatomy, and a woody stem with a deep taproot.

[13] Ultimately, molecular and morphological evidence support the inclusion of all three, confirming that the Droseraceae are a monophyletic group.

[15] Recent molecular and biochemical evidence[16] suggests the carnivorous taxa in the order Caryophyllales (the families Droseraceae, Drosophyllaceae, Nepenthaceae, and the species Triphyophyllum peltatum) all belong to the same clade, which does not consist only of carnivorous plants, but also of some noncarnivorous plants such as those in the family Ancistrocladaceae.

Darwin concluded that carnivory in plants was convergent, writing in 1875 that Utricularia and Nepenthes were not "at all related to the Droseraceae".

[18] [19] Due to the sister relationship of Dionaea and Aldrovanda, it is likely that the snap-trap mechanism only evolved once, but it is unknown if the common ancestor was terrestrial or aquatic.