Phylogenetic Relationships and Evolution in Erodium (Geraniaceae) based on trnL-trnF Sequences

Phylogenetic reconstructions in the Mediterranean genus Erodium are for the first time performed using two matrices: one with 96 trnL-trnF sequences from Erodium (90 accessions plus four outgroups) and the other with 72 trnL-trnF sequences plus 23 morphological characters (66 species of a total of 74), using Maximum Parsimony (MP) and Bayesian Inference (BI). An association between reproductive properties (high selfing rates, flower asymmetry, insect-attraction structures), life form, and breeding system distributed in different lineages suggests multiple shifts from allogamy to autogamy in the course of evolution, whereas dioecy has occurred only once. The phylogenetic analyses revealed a remarkable capability for dispersal in Erodium because closely related species occur in different continents. Major lineages containing sublineages of species also from several continents lead us to interpret ancient dispersal activity. Establishment of Mediterranean-like climates in most continents may have been crucial in the evolution of Erodium, as manifested by occurrence of species of the Mediterranean floristic region in the four major lineages. The body of knowledge accumulated from molecular phylogenetics and morphology lead us to conclude that the Mediterranean region harbors the major center of diversity of Erodium, where active radiation in dry, disturbed environments, is still operating.