Fabales is a cosmopolitan angiosperm order that consists of four families: Leguminosae (Fabaceae), Polygalaceae, Surianaceae, and Quillajaceae. Despite the great interest in this group, a convincing phylogeny of the order is still not available. Therefore, the aim of this study was to explicitly test for possible long branch attraction (LBA) problems within Fabales for the first time, and determine whether low tree stemminess and unequal branch lengths could worsen this problem. Supermatrix analysis of Fabales was carried out using previously published plastid matK, trnL, rbcL, and newly sequenced nuclear sqd1 regions for 678 taxa in total, including 43 outgroup taxa from families of Fabidae. We employed additional analyses, such as simulations, network analyses, sampling different outgroup taxa (random or real), removing fast evolving sites and fast evolving taxa, and molecular clock rooting, to identify both LBA and (or) rooting problems. These analyses clearly show that the Fabales phylogeny has been influenced by the sampling of outgroup taxa, but not LBA. However, network analyses show that even though it is weak, there is a consistent phylogenetic signal among the rapidly radiated Fabales families, which can be traced by further analyses. While, molecular clock rooting analysis yielded a (Leguminosae(Polygalaceae(Surianaceae+Quillajaceae))) topology with strong support for the first time here, supermatrix analyses yielded a ((Leguminosae+Polygalaceae)(Surianaceae+Quillajaceae)) with low-moderate support.

1) Background: The genus Euphorbia L. in Egypt is represented by 40 species, one subspecies, and three varieties which are distributed in almost all phytogeographical regions in Egypt. The genus is well known for its medicinal importance; however, various and sometimes anomalous morphological characters make the identifincation of the genus a dificult case. (2) Methods: In this study, six DNA markers: matK, rbcL, ETS, trnL intron, trnL spacer, and the entire ITS region (ITS1 + 5.8S + ITS2), as well as subunits ITS1 and ITS2 were evaluated singly and in combination to investigate their usage as potential DNA barcodes. The Maximum Likelihood (ML) and BLASTn analyses were conducted for 37 individuals representing 26 species of Egyptian Euphorbia. (3) Results: The BLASTn comparison of the newly generated DNA sequences of the Egyptian Euphorbia species showed that ITS, ITS1 and ITS2 subunits displayed high levels of species discrimination. On the other hand, the ML analysis of the DNA sequences of trnL intron yielded a better resolved phylogenetic tree, compared to the other regions. However, our phylogenetic analysis based on DNA sequences of other markers: matK, rbcL, trnL, and the entire ITS region, with additional sequences from GenBank have shown that E. dracunculoides, E. hyssopifolia, E. lasiocarpa and E. granulata are probably not monophyletic. (4) Conclusion: This study along with the widest taxon coverage in Egypt, emphasizes the importance of using DNA markers for precise identification and phylogenetic placement of the genus Euphorbia in Egypt within the whole genus.

Leguminosae, Polygalaceae, Quillajaceae and Surianaceae together comprise the order Fabales.Phylogenetic relationships within Fabales remains an unsolved problem even though interfamilial relationships have been examined in a number of studies using different sampling approaches and both molecular and morphological data. In this study, we gather information from the nuclear 26S rDNA region as well as previously published data from the sqd1, matK and rbcL regions. Phylogenetic analyses were performed by maximum parsimony, maximum likelihood, and Bayesian inference.Overall, the best-supported topology for the relationships among families within the order places the pair of Leguminosae and Polygalaceae as sister to the pair of Quillajaceae and Surianaceae. However, our approximately unbiased (AU) test of the combined data results has shown that none of the seven different topologies rejected. Furthermore, three topologies were not significantly different from each other. Therefore, similar to the previous studies, this study did not find wellsupported dichotomous relationships among the four Fabales families. The Fabales topology was very sensitive to both data choice and the phylogenetic methods used, which may indicate a rapidnear-simultaneous evolution of the four Fabales families. Our results also show that while nuclear sqd1 can be helpful as a complementary region, both the nuclear sqd1 and rDNA 26S regions could be problematic when analysed individually.

Background Keel flowers are bilaterally symmetrical, pentamerous flowers with three different petal types and reproductive organs enclosed by keel petals; generally there is also connation of floral parts such as stamens and keel petals. In this study, the evolution of keel flowers within the order Fabales is explored to investigate whether the establishment of this flower type within one of the species-rich families, the Fabaceae (Leguminosae), preceded and could have influenced the evolution of keel flowers in the Polygalaceae. We conducted molecular dating, and ancestral area and ancestral state analyses for a phylogeny constructed for 678 taxa using published matK, rbcL and trnL plastid gene regions. Results We reveal the temporal and spatial origins of keel flowers and traits associated with pollinators, specifically floral symmetry, the presence or absence of a pentamerous corolla and three distinct petal types, the presence or absence of enclosed reproductive organs, androecium types, inflorescence types, inflorescence size, flower size, plant height and habit. Ancestral area reconstructions show that at the time keel flowers appeared in the Polygaleae, subfamily Papilionoideae of the Fabaceae was already distributed almost globally; at least eight clades of the Papilionoideae had keel flowers with a functional morphology broadly similar to the morphology of the first evolving Polygaleae flowers. Conclusions The multiple origins of keel flowers within angiosperms likely represent convergence due to bee specialization, and therefore pollinator pressure. In the case of the Fabales, the first evolving keel flowers of Polygaleae have a functional morphology that corresponds with keel flowers of species of the Papilionoideae already present in the environment. These findings are consistent with the keel-flowered Polygaleae exploiting pollinators of keel-flowered Papilionoideae. The current study is the first to use ancestral reconstructions of traits associated with pollination to demonstrate that the multiple evolutionary origins of the keel flower pollinator syndrome in Fabales are consistent with, though do not prove, mimicry.

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