Historically, the genus Chrysanthemum, consisted of a large number of species of flowering plants. In recent decades, however, taxonomists have been busy separating plants that were once called Chrysanthemum into several other genera. There is still some disagreement as to the validity of some of these changes, however, as it currently stands, some of the plants once called chrysanthemum are now classified in other  genera including:  Argyranthemum, Dendranthema, Leucanthemopsis, Leucanthemum, Rhodanthemum, and Tanacetum.