[4] It also includes the members of the former families of the pomegranate (Punica granatum, formerly in Punicaceae) and of the water caltrop (Trapa natans, formerly in Trapaceae).

[5] Traits shared by species within the Lythraceae that distinguish them from belonging to other plant families are the petals being crumpled in the bud and the many-layered outer integument of the seed.

[4] Heterostyly – the presence of two (distylous) or three (tristylous) distinct flower morphs within a species differing in the lengths of the pistil and stamens – is common within the Lythraceae.

[4][5] The oldest fossils of the family are pollen from the Late Cretaceous (Campanian) of Wyoming in western North America, around 82 to 81 million years old.

[9] Edible crops include the pomegranate (Punica granatum) and the water caltrop (Trapa bicornis or T. natans).

Ornamentals are grown from a number of genera, including Cuphea, Lagerstroemia (crape myrtles), and Lythrum (loosestrifes).

[4] Purple loosestrife (Lythrum salicaria) is an invasive exotic weed of wetlands throughout Canada and the United States.

[4][8] Molecular phylogeny work has led to the inclusion of the formerly recognized families Duabangaceae, Punicaceae, Sonneratiaceae, and Trapaceae.