The genus Artocarpus (Moraceae) comprises approximately 60 tree species native to the tropical lowland forests of Southeast Asia. Several species are utilized for their timber or their large, edible syncarpous fruits, including the circumtropically cultivated breadfruit, A. altilis, and jackfruit, A. heterophyllus. The genus is divided into two subgenera based on leaf arrangement, stipule and leaf anatomical characters, and whether the perianths of the syncarpous fruits are partially (subgenus Artocarpus) or entirely (subgenus Pseudojaca) connate. The closely allied genus Prainea shares all the leaf anatomical and stipule characters with subgenus Pseudojaca, but the perianths of its multiple fruit are entirely distinct. This has led different researchers to either treat Prainea as its own genus or as a third subgenus within Artocarpus. Both nuclear and plastid DNA sequence data were analyzed to create a phylogenetic hypothesis for Artocarpus, Prainea and outgroup taxa. The phylogeny was then used to test the monophyly of Artocarpus and the sections within the genus. The findings have implications for the placement of Prainea and the identification of breadfruit's closest wild relatives.

Key words: Artocarpus, breadfruit, molecular phylogeny, Moraceae, Prainea, Southeast Asia