Figure 1

Strict consensus of 1780 most parsimonious trees inferred from the dataset consisting of three concatenated, complete ITS alignments. The topology was rooted with Ustilentyloma brefeldii and U. fluitans. Symbols on branches indicate the magnitude of parsimony bootstrap values from analyses of the dataset after exclusion of alignment-ambiguous sites (upper left) and of the three different, complete alignments made with MAFFT (upper right), PCMA (lower left), and POA (lower right). The right side of the picture reports morphological features of the specimens included in our data set. The symbols and abbreviations used are as follows. Form of spore ornamentation: filled-in circle, smooth spores; hollow square, verrucose spores; filled-in square, reticulate spores. Height of spore ornamentation: filled-in circle, smooth spores; hollow square, flat ornamentation; filled-in square, high ornamentation. Disjunctors, columella: hollow square, absent; filled-in square, present. Forming galls with an apical lunular bed of spore masses: hollow square, absent; filled-in square, present. Sorus location: Leav, leaves; St, Stems; Inf, inflorescence axis; Ped, pedicels; Flow, swollen (and often deformed) whole flowers; Ovar, ovaries only; Seed, seeds only; Fil, filaments only; Anth, anthers only. Host family: Poac, Poaceae; Junc, Juncaceae; Poly, Polygonaceae; Lent, Lentibulariaceae; Lami, Lamiaceae; Dips, Dipsacaceae; Aste, Asteraceae; Cary, Caryophyllaceae; M., Microbotryum; M. tragopo.-pratensis, Microbotryum tragopogonis-pratensis; M. v.-irregulare, Microbotryum violaceo-irregulare; M. v.-verrucosum, Microbotryum violaceo-verrucosum; S., Sphacelotheca.