Abstract: In this paper, the molecular phylogeny of the sequences of nrDNA ITS and rpS16 regions of 13 species representing Lappula Moench was studied by taking Arnebia guttata and Coldenia procumbens as the outgroups and by using PAUP* 4.0. Consistent phylogenetic trees were obtained with the maximum likelihood and the maximum parsimony methods based on DNA sequence datasets. The topologies of gene trees revealed that the Lappula was monophyly, and the previous studies failed to avoid the subjectivity in the taxonomic categories and identified characters of the genus, making it unable to reflect the actual phylogenetic relationships of Lappula. Combining with morphology characteristics, this study concluded that the corollas of Lappula evolved from small form to large form, fruits from homotype to heterotype, and nutlet fringes from tuberculate or prickly one to winged one.  

Key words: Lappula, ITS sequence, rpS16 sequence, phylogeny