Present-day native distribution of actinorhizal plant hosts. (A) Distribution of plant hosts for CcI3, including Casuarina and Allocasuarina of the Casuarinaceae (C). (B) Distribution of plant hosts for ACN, including Alnus sp. in the Betulaceae (B) and Myricaceae (M) and their overlap (M+B). (C) Distribution of plant hosts for EAN including members of the Elaeagnaceae (E), Myricaceae (M), and the actinorhizal Tribe Colletieae of the Rhamnaceae in South America, Australia, and New Zealand (R). Elaeagnaceae and Myriceae (E+M) overlap in some areas. Maps were drawn with information from Silvester (1977) and from the Missouri Botanical Garden Web site (www.mobot.org).