A MOLECULAR PHYLOGENY OF CELTIDACEAE AND ULMACEAE (URTICALES) BASED ON RBCL NUCLEOTIDE-SEQUENCES

On the basis of 1,290 bp sequences of the chloroplast gene rbcL, a mol ecular phylogeny of seven of nine genera of the Celtidaceae and four o f six genera of the Ulmaceae was produced. These data were analyzed to gether with some other urticalean genera using three methods (i.e., ma ximum parsimony, maximum likelihood, and neighbor joining methods). Ma ximum likelihood topology among 18 trees obtained indicated that the U rticales are monophyletic with its common clade splitting basally into two: one leading to a line comprising Ampelocera (traditionally place d in Celtidaceae) and Ulmaceae, and the other leading to a line compri sing the remaining genera of Celtidaceae, Moraceae, and other Urticale s. Ulmaceae, to which Ampelocera is a sister group, are monophyletic, as supported by many lines of morphological evidence. In contrast to U lmaceae, the monophyly of Celtidaceae (excluding Ampelocera) was not s upported, and resolution of relationships of Celtidaceae with other Ur ticales, as well as of those within the family, is left for future stu dy.