Lamiaceae are biogeographically remarkable not only because the family has undergone a virtual worldwide radiation, but also because this radiation has involved disparate clades in different parts of the world (often on different continents) and thus may be viewed as a series of nested radiations. Lamiaceae, while nearly cosmopolitan, are especially diverse in seven regions of the world: Mediterranean and SW-Central Asia, Sub-Saharan Africa and Madagascar, China, Australia, South America, North America (including Mexico), and Indomalaysia (Hedge 1992; Harley et al. 2004).