Taxonomic revision of the Vitex trifolia complex (Lamiaceae).

The complex is a well-circumscribed and monophyletic group. However, the species of the group are morphologically very similar and therefore, taxonomic boundaries within the group are uncertain. In addition, these medicinal plants have been cultivated and naturalised in many areas across the world and therefore their natural geographical distributions are not well known. A taxonomic account of the complex is presented in which nine species are recognized: , , , , , and ; a new species, Sengun, is described from frost prone regions of northern and Central China and an obscure name, Moldenke, is recognised for the Indian specimens previously recognized as . In addition, , , , , f. , f. , f. , and var. are lectotypified, and Blanco has been neotypified. Also, many names have been placed in synonomy for the first time.