I suspect we have in such families as Alzateaceae, Rhynchocalycaceae, Penaeaceae and Oliniaceae an additional series of rather specialized forms relating to their habit, but as a group, all are less advanced than Lythraceae. For example, the ericoid aspect of the South African family Penaeaceae is representative of this type of specialization. Lagerstroemia and Lythrum are well-known in the horticultural trade, with Cuphea rapidly joining them. The latter has also been a subject of interest because of its potential value as an oil seed. Some of the arborescent species are harvested for their lumber.
Some species are sources of dyes.
The tristylous flowers of L. salicaria was made famous by Darwin in a series of studies on pollination. This species is now a major weed in many marshlands in temperate regions of the world, including eastern North America. Nearly 130 genera and more than 3900 species. Tropical and subtropical regions of the world, especially in Australia, a few in warm Temperate regions. Beilschm., has also been promoted but seems equally unworthy of formal recognition.