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The Golovinomyces cichoracearum complex is morphologically highly variable and causes powdery mildew on a wide range of Compositae, including Hieracium spp. and Lapsana communis. A comprehensive phylogenetic analysis of Golovinomyces, published in 2013, revealed that G. cichoracearum s. str. was confined to Scorzonera and Tragopogon spp. as hosts (Compositae, tribe Lactuceae, subtribe Scorzonerinae). To clarify the phylogeny and taxonomy of Golovinomyces on Hieracium spp. (Compositae, tribe Lactuceae, subtribe Hieraciinae), which is common in Asia and Europe, morphology and phylogenetic analyses of ITS + 28S rDNA sequences were conducted for 57 powdery mildew specimens of Hieracium spp. and Lapsana communis. Golovinomyces on Hieracium spp. in Asia and Europe, previously referred to as G. cichoracearum, is a previously undescribed, cryptic species, which is described here as Golovinomyces hieraciorum sp. nov. Since a sequence retrieved from a powdery mildew on Lapsana communis in Switzerland clustered in sister position to the G. hieraciorum clade, numerous German specimens identified as G. cichoracearum were included in the present examinations. All the re-examined collections of "G. cichoracearum" on L. communis were misidentified, and were shown to belong to Neoërysiphe nevoi or Podosphaera ergerontis-canadensis. [ABSTRACT FROM AUTHOR]

The phylogenetic position of Uncinula forestalis within the Erysiphales has been inferred from 5.8S, 18S, and 28S rDNA sequences. Although the appendages of the ascomata are Uncinula-like, i.e. unbranched with curved-coiled apices, U. forestalis is situated at the very base of the large Erysiphales cluster, far from the ‘Pseudoidium’ clade (Erysiphe, including Microsphaera and Uncinula) and separate from the recently introduced basal genus Parauncinula. U. forestalis differs morphologically from the species of Erysiphe sect. Uncinula in having terminal, fasciculate (as in Podosphaera tridactyla), septate ascoma appendages and a Euoidium-like anamorph (conidia catenate). In Parauncinula, the appendages are also terminal but not fasciculate, the ascospores are curved, and the anamorph is lacking. Uncinula forestalis is a basal, tree-inhabiting powdery mildew with some additional ancestral characteristics, including Uncinula-like appendages and 6–8-spored asci. The new genus Caespitotheca gen. nov. is described with C. forestalis comb. nov. (syn. Uncinula forestalis) as the type species. We calculated the timing of the divergence of U. forestalis and P. septata using a molecular clock of the Erysiphales (6.5×10−10 changes per site per year in domains D1 and D2 of 28S rDNA) and a 28S rDNA data set. The results suggest that the divergence of U. forestalis and P. septata from other Erysiphales occurred between 90 and 80 Myr ago; i.e. the divergence of the two ancestral species may have occurred in the late Cretaceous. [ABSTRACT FROM AUTHOR]

Mycosphaerella punctiformis, the type species of the genus Mycosphaerella, is epitypified by material collected on Quercus robur in The Netherlands. The teleomorph is described in planta, and the Ramularia anamorph, for which the new name R. endophylla is proposed, and the Asteromella spermatial state are characterized in vitro. Sequence data of the nuclear ribosomal DNA are presented and analyzed together with other Mycosphaerella spp. with Ramularia and several other anamorphs. Several strains originating from Quercus, Acer and Tilia showed diverging ITS sequences, indicating that the M. punctiformis complex may comprise more than a single phylogenetic species, but this could not be confirmed by the analysis of our dataset. An endophytic phase is established for the first time in the life-cycle of M. punctiformis, as the species was repeatedly isolated from surface sterilized green healthy leaves of Quercus robur in summer at the epitype locality. [ABSTRACT FROM AUTHOR]