Phylogenetic analysis have been conducted on representatives of
Poaceae groups temptatively placed within subtribes Cynosurinae,
Dactylinae, Loliinae, Parapholiinae, Phalaridinae, Poinae, and
Sesleriinae. Sequences from the nuclear ITS region and from the
chloroplast trnL-F region have been analyzed either separately or
combinedly to obtain a reconstruction of the evolutionary
relationships between these predominantly Western Mediterranean
lineages. The structures shown on the resulting topologies
differentiate several suprageneric groups that could be reaccomodated
within Poeae s. lat. Some of the best supported clades represent the
links of: 1) Festuca s.s. + Vulpia + Wangenheimia + Ctenopsis+
Psilurus; 2) Schedonorus + Lolium; 3) Dactylis + Lamarckia+ Parapholis
+ Monerma + Catapodium + Sphenopus + Cynosurus. Leucopoa, and
Drymanthele + Scariosa + Subbulbosae could be resolved either
separated or basal to Schedonorus + Lolium. Sesleria and Poa are
respectively sister lineages to the other studied taxa. Conflicts
between the nuclear and the chloroplast trees are likely due to past
intergroup hybridization events. Evaluation of changes of structural
characters on the molecular trees confirms their phylogenetic value at
some hierarchical levels.
Key words: combined phylogenies, ITS, Poeae, reclassification of groups, trnL-F