ABSTRACT:

There are two major centers of distribution, the Americas, with 35 endemic genera and Asia with 34 endemic genera. Despite this almost equal distribution of genera between the two areas, there are great differences in species richness. For example, about 1350 described species or 55% of the total for the family are restricted to tropical America. My recently acquired experience with distri bution of Araceae in the Old World tropics leads me to believe that real percentages will be even greater for the American tropics. A recently completed four month long field trip to Australia, southeast Asia and Africa allowed me to compare the aroids in these areas with those in the areas visited during the last 17 years in tropical America.