<i>Didymellaceae</i> species associated with <i>Convolvulaceae</i> plants, with description of three new species

<i>Didymellaceae</i> is one of the largest families in the <i>Pleosporales</i>, encompassing main genera of <i>Phoma</i>-like fungi including <i>Ascochyta, Didymella</i>, and <i>Stagonosporopsis</i> and representing underestimated biodiversity. Plants in the <i>Convolvulaceae</i> often grow as weeds in many climates and host a wide range of fungi in the <i>Didymellaceae</i>. This study identified 22 <i>Didymellaceae</i> strains isolated from plants in the <i>Convolvulaceae</i> according to the consolidated species concept (CSC) using phylogenetic, micromorphological, and cultural features. Multilocus phylogenetic analysis inferred from nucleotide sequences of the internal transcribed spacer (ITS), large subunit (28S) of ribosomal DNA, partial DNA-directed RNA polymerase II subunit (<i>rpb2</i>), and β-tubulin (<i>tub2</i>) genes revealed well-supported monophyletic clades corresponding to 16 <i>Didymellaceae</i> species. Reported here for the first time from the <i>Convolvulaceae</i> hosts are <i>Didymella americana, D. bellidis, D. glomerata, D. pomorum, D. segeticola, D. sinensis, D. tanaceti, Nothophoma brennandiae, N. gossypiicola, Phomatodes nebulosa, Stagonosporopsis caricae, S. heliopsidis</i>, and <i>S. inoxydabilis</i>. Additionally, three new species were described: <i>Didymella pseudomacrophylla</i>, sp. nov. <i>Epicoccum convolvulicola</i>, sp. nov. and <i>Epicoccum pseudoplurivorum</i>, sp. nov. Seven species are reported for the first time from Russia: <i>D. bellidis, D. segeticola, D. sinensis, D. tanaceti, N. brennandiae, P. nebulosa</i>, and <i>S. caricae</i>, and one species, <i>S. heliopsidis</i>, for the first time from Kazakhstan.