Phylogeny of Ononis in Iran using nuclear ribosomal DNA and chloroplast sequence data

The genus Ononis, embraces more than 85 species worldwide. In the present study, materials of two subspecies of O. spinosa from different localities of Iran alongside some other native species of the genus were included in phylogenetic analyses. In addition, over 50 accessions were obtained from GenBank. In order to clarify the exact number of subspecies of O. spinosa in Iran, datasets were obtained from sequencing of nuclear ribosomal ITS (nr DNA ITS) and trnL-F plastid (cp DNA) regions and analysed. Three taxa belonging to O. spinosa L. complex (O. spinosa subsp. leiosperma, O. spinosa subsp. antiquorum, and O. arvensis=O. spinosa subsp. arvensis) were previously reported from Iran. Based on Maximum Parsimony and Bayesian analyses of the molecular datasets, it is shown that, unlike the previous reports, Iranian O. spinosa complex belongs to only two subspecies (i.e. leiosperma and arvensis subspp.). In addition, we also found that, O. spinosa subsp. antiquorum is not present in Iran. It was also demonstrated that, seed sculpturing does not provide valuable characters in diagnosing different subspecies of O. spinosa.